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    <us-gaap:BusinessDescriptionAndAccountingPoliciesTextBlock contextRef="From2021-01-01to2021-09-30">&lt;p id="xdx_801_eus-gaap--BusinessDescriptionAndAccountingPoliciesTextBlock_zSlQeFO0Fml9" style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Note
1. &lt;span id="xdx_828_zUuL0SvYFOl2"&gt;Business Description&lt;/span&gt;&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Celsion
Corporation (&#x201c;Celsion&#x201d; and the &#x201c;Company&#x201d;) is a fully integrated, clinical stage biotechnology company focused
on advancing a portfolio of innovative treatments including DNA-based immunotherapies, next generation vaccines and directed chemotherapies
through clinical trials and eventual commercialization. The Company&#x2019;s product pipeline includes GEN-1, a DNA-based immunotherapy
for the localized treatment of ovarian cancer and ThermoDox&lt;sup&gt;&#xae;&lt;/sup&gt;, a proprietary heat-activated liposomal encapsulation of
doxorubicin, currently under investigator-sponsored development for several cancer indications. Celsion has two feasibility stage platform
technologies for the development of novel nucleic acid-based immunotherapies and next generation vaccines and other anti-cancer DNA or
RNA therapies. Both are novel synthetic, non-viral vectors with demonstrated capability in nucleic acid cellular transfection.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

</us-gaap:BusinessDescriptionAndAccountingPoliciesTextBlock>
    <us-gaap:BasisOfAccounting contextRef="From2021-01-01to2021-09-30">&lt;p id="xdx_806_eus-gaap--BasisOfAccounting_zuAhrodZ9SMb" style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Note
2. &lt;span id="xdx_82A_zWw4VYjk3BR2"&gt;Basis of Presentation&lt;/span&gt;&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;The
accompanying unaudited condensed consolidated financial statements, which include the accounts of the Company and its wholly owned subsidiaries,
CLSN Laboratories, Inc. and Celsion, GmbH, have been prepared in accordance with generally accepted accounting principles in the United
States (GAAP) for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X. All significant
intercompany balances and transactions have been eliminated in consolidation. Certain information and disclosures normally included in
financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to such rules and regulations.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;In
the opinion of management, all adjustments, consisting only of normal recurring accruals considered necessary for a fair presentation,
have been included in the accompanying unaudited condensed consolidated financial statements. Operating results for the three-month and
nine-month periods ended September 30, 2021 and 2020 are not necessarily indicative of the results that may be expected for any other
interim period(s) or for any full year. For further information, refer to the consolidated financial statements and notes thereto included
in the Company&#x2019;s Annual Report on Form 10-K for the fiscal year ended December 31, 2020 filed with the Securities and Exchange
Commission (SEC) on March 19, 2021.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;The
preparation of financial statements in conformity with GAAP requires management to make judgments, estimates, and assumptions that affect
the amount reported in the Company&#x2019;s financial statements and accompanying notes. Actual results could differ materially from those
estimates. Events and conditions arising subsequent to the most recent balance sheet date have been evaluated for their possible impact
on the financial statements and accompanying notes. The Company continues to monitor the impact of the COVID-19 pandemic on its financial
condition and results of operations, along with the valuation of its long-term assets, intangible assets, and goodwill. The effect of
this matter could potentially have an impact on the valuation of such assets in the future. The COVID-19 pandemic is discussed in more
detail in Note 3 to the financial statements.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

</us-gaap:BasisOfAccounting>
    <us-gaap:SubstantialDoubtAboutGoingConcernTextBlock contextRef="From2021-01-01to2021-09-30">&lt;p id="xdx_807_eus-gaap--SubstantialDoubtAboutGoingConcernTextBlock_zadzfL2zK6d2" style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Note
3. &lt;span id="xdx_82F_zQZ3bust5XCl"&gt;Financial Condition and Business Plan&lt;/span&gt;&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Since
inception, the Company has incurred substantial operating losses, principally from expenses associated with the Company&#x2019;s research
and development programs, clinical trials conducted in connection with the Company&#x2019;s product candidates, and applications and submissions
to the U.S. Food and Drug Administration. The Company has not generated significant revenue and has incurred significant net losses in
each year since our inception. As of September 30, 2021, the Company has incurred approximately $&lt;span id="xdx_90F_eus-gaap--RetainedEarningsAccumulatedDeficit_iNI_pn6n6_di_c20210930_zBuD81k7UoK5" title="Cumulative net losses"&gt;329&lt;/span&gt; million of cumulative net losses
and had approximately $&lt;span id="xdx_90B_ecustom--CashAndCashEquivalentsRestrictedCashShorttermInvestmentsAndReceivableOnSaleOfNetOperatingLosses_iI_pn5n6_c20210930_zTr9L0yPhISh" title="Cash and cash equivalents, restricted cash, short-term investments, interest receivable"&gt;60.6&lt;/span&gt; million in cash and cash equivalents, restricted cash, short-term investments and interest receivable. We
have substantial future capital requirements to continue our research and development activities and advance our product candidates through
various development stages. The Company believes these expenditures are essential for the commercialization of its technologies.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;The
Company expects its operating losses to continue for the foreseeable future as it continues its product development efforts, and when
it undertakes marketing and sales activities. The Company&#x2019;s ability to achieve profitability is dependent upon its ability to obtain
governmental approvals, manufacture, and market and sell its product candidates. There can be no assurance that the Company will be able
to commercialize its technology successfully or that profitability will ever be achieved. The operating results of the Company have fluctuated
significantly in the past.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;



&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"/&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;In
January 2020, the WHO declared an outbreak of coronavirus, COVID-19, to be a &#x201c;Public Health Emergency of International Concern,&#x201d;
and the U.S. Department of Health and Human Services declared a public health emergency to aid the U.S. healthcare community in responding
to COVID-19. This virus has spread to over 100 countries, including the U.S. Governments and businesses around the world have taken unprecedented
actions to mitigate the spread of COVID-19, including, but not limited to, shelter-in-place orders, quarantines, significant restrictions
on travel, as well as restrictions that prohibit many employees from going to work. Uncertainty with respect to the economic impacts
of the pandemic has introduced significant volatility in the financial markets. The Company did not observe significant impacts on its
business or results of operations during 2020 and into 2021 due to COVID-19. While the extent to which COVID-19 impacts the Company&#x2019;s
future results will depend on future developments, the pandemic and associated economic impacts could result in a material impact to
the Company&#x2019;s future financial condition, results of operations and cash flows. The Company&#x2019;s ability to raise additional
capital may be adversely impacted by potential worsening global economic conditions and the recent disruptions to, and volatility in,
financial markets in the U.S. and worldwide resulting from the ongoing COVID-19 pandemic. The disruptions caused by COVID-19 may also
disrupt the clinical trials process and enrolment of patients. This may delay commercialization efforts. The Company continues to monitor
its operating activities in light of these events. The specific impact, if any, is not readily determinable as of the date of these financial
statements.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;The
actual amount of funds the Company will need to operate is subject to many factors, some of which are beyond the Company&#x2019;s control.
These factors include the following:&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

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    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;the
    progress of research activities;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
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    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: top"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#x25cf;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;the
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    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: top"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#x25cf;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;the
    progress of preclinical and clinical development activities;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: top"&gt;
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    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: top"&gt;
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    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;the
    progress of the development efforts of parties with whom the Company has entered into research and development agreements;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
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    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: top"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#x25cf;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;the
    costs associated with additional clinical trials of product candidates;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: top"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: top"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#x25cf;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;the
    ability to maintain current research and development licensing arrangements and to establish new research and development and licensing
    arrangements;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: top"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: top"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#x25cf;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;the
    ability to achieve milestones under licensing arrangements;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: top"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: top"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#x25cf;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;the
    costs involved in prosecuting and enforcing patent claims and other intellectual property rights; and&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: top"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: top"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#x25cf;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;the
    costs and timing of regulatory approvals.&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;
&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;On
July 13, 2020, the Company announced that it has received a recommendation from the independent Data Management Committee (&#x201c;DMC&#x201d;)
to consider stopping the global Phase III OPTIMA Study of ThermoDox&lt;sup&gt;&#xae; &lt;/sup&gt;in combination with RFA for the treatment of HCC,
or primary liver cancer. The recommendation was made following the second pre-planned interim safety and efficacy analysis by the DMC
on July 9, 2020. The DMC&#x2019;s analysis found that the pre-specified boundary for stopping the trial for futility of 0.900 was crossed
with an actual value of 0.903. The Company followed the advice of the DMC and considered its options to either stop the study or continue
to follow patients after a thorough review of the data, and an evaluation of the probability of success. On February 11, 2021, the Company
issued a letter to shareholders stating that the Company was notifying all clinical sites to discontinue following patients in the OPTIMA
Study.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;During
2020, 2019 and 2018, the Company submitted applications to sell a portion of the Company&#x2019;s State of New Jersey net operating losses
as part of the Technology Business Tax Certificate Program sponsored by The New Jersey Economic Development Authority. Under the program,
emerging biotechnology companies with unused NOLs and unused research and development credits are allowed to sell these benefits to other
New Jersey-based companies. In 2018 and 2019, the Company sold cumulative NOL&#x2019;s from 2011 to 2018 NOLs totaling $&lt;span id="xdx_907_ecustom--NetProceedsFromSaleOfNetOperatingLosses_c20180101__20181231__srt--StatementGeographicalAxis__custom--NJMember_pn6n6" title="[custom:NetProceedsFromSaleOfNetOperatingLosses]"&gt;13&lt;/span&gt; million receiving
net proceeds of $&lt;span id="xdx_900_ecustom--NetProceedsFromSaleOfNetOperatingLosses_pn5n6_c20190101__20191231__srt--StatementGeographicalAxis__custom--NJMember_znRCqEcDElFc" title="Net proceeds from sale of net operating losses"&gt;12.2&lt;/span&gt; million. In June 2020 and as updated in September 2020, the Company filed an application with the New Jersey Economic
Development Authority to sell substantially all of its remaining State of New Jersey net operating losses totaling $&lt;span id="xdx_902_ecustom--NetProceedsFromSaleOfNetOperatingLosses_pn5n6_c20200901__20200930__srt--StatementGeographicalAxis__custom--NJMember_zniJFKhXeqMf" title="Net proceeds from sale of net operating losses"&gt;2.0&lt;/span&gt; million available
under the program. On February 12, 2021, the New Jersey Economic Development Authority approved the full amount of the Company&#x2019;s
application. In February of 2021, the Company entered into an agreement to sell the net operating losses from the 2020 application and
the Company received net proceeds of approximately $&lt;span id="xdx_909_ecustom--ReceivableOnSaleOfNetOperatingLosses_iI_pn4n6_c20210930_zIekzNLZo776" title="Receivable on sale of net operating losses"&gt;1.85&lt;/span&gt; million on May 10, 2021. During 2021, the New Jersey State Legislature increased
the maximum lifetime benefit per company from $&lt;span id="xdx_90C_ecustom--NetProceedsFromSaleOfNetOperatingLosses_pn6n6_c20210101__20210929__srt--StatementGeographicalAxis__custom--NJMember_z2bQlSZT3lKd" title="Net proceeds from sale of net operating losses"&gt;15&lt;/span&gt; million to $&lt;span id="xdx_903_ecustom--NetProceedsFromSaleOfNetOperatingLosses_pn6n6_c20210101__20210930__srt--StatementGeographicalAxis__custom--NJMember_zunqH9HXQPFi" title="Net proceeds from sale of net operating losses"&gt;20&lt;/span&gt; million, which will allow the Company to participate in this program
in future years. On June 16, 2021, the Company filed another application to sell approximately $&lt;span id="xdx_904_ecustom--NetProceedsFromSaleOfNetOperatingLosses_c20210615__20210616__srt--StatementGeographicalAxis__custom--NJMember_pn5n6" title="[custom:NetProceedsFromSaleOfNetOperatingLosses]"&gt;1.6&lt;/span&gt; million of net operating losses during
2021 and expects to receive up to approximately $&lt;span id="xdx_903_ecustom--NetProceedsFromSaleOfNetOperatingLosses_pn5n6_c20210615__20210616__srt--StatementGeographicalAxis__custom--NJMember__srt--RangeAxis__srt--MaximumMember_z8G42ULUvio2" title="Net proceeds from sale of net operating losses"&gt;1.4&lt;/span&gt; million under the current year program.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"/&gt;



&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"/&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;In
June 2018, the Company entered into a Credit Agreement with Horizon Technology Finance Corporation (&#x201c;Horizon&#x201d;) that provided
$&lt;span id="xdx_905_eus-gaap--ProceedsFromContributedCapital_pn6n6_c20180601__20180630__us-gaap--TypeOfArrangementAxis__custom--HorizonCreditAgreementMember__dei--LegalEntityAxis__custom--HorizonTechnologyFinanceCorporationMember_zfUsFELziOtk" title="Proceeds from Contributed Capital"&gt;10&lt;/span&gt; million in capital (the &#x201c;Horizon Credit Agreement&#x201d;). The obligations under the Horizon Credit Agreement are secured by
a first-priority security interest in substantially all assets of Celsion other than intellectual property assets. &lt;span id="xdx_90B_eus-gaap--DebtInstrumentDescription_c20210101__20210930__us-gaap--TypeOfArrangementAxis__custom--SVBLoanFacilityMember" title="Debt Instrument, Description"&gt;Payments under the
loan agreement are interest only (calculated based on one-month LIBOR plus &lt;span id="xdx_90C_eus-gaap--DebtInstrumentInterestRateStatedPercentage_iI_pid_dp_uPure_c20180930__us-gaap--TypeOfArrangementAxis__custom--HorizonCreditAgreementMember__dei--LegalEntityAxis__custom--HorizonTechnologyFinanceCorporationMember__us-gaap--VariableRateAxis__us-gaap--LondonInterbankOfferedRateLIBORMember_zkMjoeMJh1e4" title="Debt Instrument, Interest Rate, Stated Percentage"&gt;7.625&lt;/span&gt;%) for the first 24 months through July 2020, followed
by a 21-month amortization period of principal and interest starting on August 1, 2020 and ending through the scheduled maturity date&lt;/span&gt;
on April 1, 2023. On August 28, 2020, in connection with an Amendment to the Horizon Credit Agreement, Celsion repaid $&lt;span id="xdx_901_eus-gaap--RepaymentsOfNotesPayable_c20200827__20200828__us-gaap--TypeOfArrangementAxis__custom--AmendmentToHorizonCreditAgreementMember__dei--LegalEntityAxis__custom--HorizonTechnologyFinanceCorporationMember_pn6n6" title="Repayments of Notes Payable"&gt;5&lt;/span&gt; million of the
$&lt;span id="xdx_90B_eus-gaap--DebtInstrumentFaceAmount_c20200828__us-gaap--TypeOfArrangementAxis__custom--HorizonCreditAgreementMember__dei--LegalEntityAxis__custom--HorizonTechnologyFinanceCorporationMember_pn6n6" title="Debt Instrument, Face Amount"&gt;10&lt;/span&gt; million loan and $&lt;span id="xdx_90F_ecustom--PaymentOfDebtEndTermCharges_c20200827__20200828__us-gaap--TypeOfArrangementAxis__custom--AmendmentToHorizonCreditAgreementMember__dei--LegalEntityAxis__custom--HorizonTechnologyFinanceCorporationMember_pn5n6" title="Debt instrument related end term charges"&gt;0.2&lt;/span&gt; million in related end of term charges, and the remaining $&lt;span id="xdx_90D_eus-gaap--DebtInstrumentFaceAmount_c20200828__us-gaap--TypeOfArrangementAxis__custom--AmendmentToHorizonCreditAgreementMember__dei--LegalEntityAxis__custom--HorizonTechnologyFinanceCorporationMember_pn6n6" title="Debt Instrument, Face Amount"&gt;5&lt;/span&gt; million in obligations were restructured. As more
fully discussed in Note 11 to these condensed consolidated financial statements, in June 2021, the Company entered into a $&lt;span id="xdx_908_eus-gaap--LineOfCreditFacilityMaximumBorrowingCapacity_c20210930__us-gaap--RelatedPartyTransactionsByRelatedPartyAxis__custom--SiliconValleyBankMember__us-gaap--TypeOfArrangementAxis__custom--SVBLoanFacilityMember_pn6n6" title="Line of Credit Facility, Maximum Borrowing Capacity"&gt;10&lt;/span&gt; million
loan facility with Silicon Valley Bank. The Company immediately used $&lt;span id="xdx_90F_ecustom--RepaymentOfOutstandingIndebtednessAmount_iI_pn6n6_c20210930__dei--LegalEntityAxis__custom--HorizonTechnologyFinanceCorporationMember__us-gaap--TypeOfArrangementAxis__custom--SVBLoanFacilityMember_z81hERw4qHFd" title="Repayment of outstanding in-debtedness amount"&gt;6&lt;/span&gt; million from this facility to retire all outstanding indebtedness
with Horizon Technology Finance Corporation. The remaining $&lt;span id="xdx_90A_eus-gaap--LineOfCreditFacilityRemainingBorrowingCapacity_c20210930__us-gaap--RelatedPartyTransactionsByRelatedPartyAxis__custom--SiliconValleyBankMember__us-gaap--TypeOfArrangementAxis__custom--SVBLoanFacilityMember_pn6n6" title="Line of Credit Facility, Remaining Borrowing Capacity"&gt;4&lt;/span&gt; million will be available to be drawn down up to 12 months after closing
and will be used for working capital and to fund the advancement of the Company&#x2019;s product pipelines. The funding is in the form
of money market secured indebtedness bearing interest at a calculated WSJ Prime-based variable rate of &lt;span id="xdx_90F_eus-gaap--DebtInstrumentInterestRateStatedPercentage_iI_pid_dp_uPure_c20210930__us-gaap--RelatedPartyTransactionsByRelatedPartyAxis__custom--SiliconValleyBankMember__us-gaap--VariableRateAxis__us-gaap--PrimeRateMember__us-gaap--TypeOfArrangementAxis__custom--SVBLoanFacilityMember_zKLfpvBdYnzd" title="Debt Instrument, Interest Rate, Stated Percentage"&gt;3.25&lt;/span&gt;%. Payments under the loan
agreement are interest only for the first 24 months after loan closing, followed by a 24-month amortization period of principal and interest
through the scheduled maturity date.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;As
more fully discussed in Note 12, during 2021 through the date of the filing of this Quarterly Report on Form 10-Q, the Company has raised
approximately $&lt;span id="xdx_901_eus-gaap--ProceedsFromContributedCapital_c20210317__20210319__us-gaap--TypeOfArrangementAxis__custom--CapitalOnDemandTMSalesAgreementMember__dei--LegalEntityAxis__custom--JonesTradingInstitutionalServicesLLCMember_pn5n6" title="Proceeds from Contributed Capital"&gt;6.9&lt;/span&gt; million in gross proceeds from the use of its JonesTrading Capital on Demand&lt;sup&gt;TM&lt;/sup&gt; financing facility, $&lt;span id="xdx_90C_eus-gaap--DebtInstrumentFaceAmount_c20210131__us-gaap--TypeOfArrangementAxis__custom--CapitalOnDemandTMSalesAgreementMember__dei--LegalEntityAxis__custom--JonesTradingInstitutionalServicesLLCMember_pn6n6" title="Debt Instrument, Face Amount"&gt;35&lt;/span&gt;
million from a registered direct financing completed in January 2021, $&lt;span id="xdx_900_eus-gaap--DebtInstrumentFaceAmount_c20210405__us-gaap--TypeOfArrangementAxis__custom--CapitalOnDemandTMSalesAgreementMember__dei--LegalEntityAxis__custom--JonesTradingInstitutionalServicesLLCMember_pn6n6" title="Debt Instrument, Face Amount"&gt;15&lt;/span&gt; million from a registered direct financing completed on April
5, 2021, and $&lt;span id="xdx_905_eus-gaap--ProceedsFromWarrantExercises_c20210101__20210131__us-gaap--TypeOfArrangementAxis__custom--CapitalOnDemandTMSalesAgreementMember__dei--LegalEntityAxis__custom--JonesTradingInstitutionalServicesLLCMember_pn5n6" title="Proceeds from Warrant Exercises"&gt;1.5&lt;/span&gt; million from warrant exercises. With $&lt;span id="xdx_905_ecustom--CashAndCashEquivalentsRestrictedCashShorttermInvestmentsAndReceivableOnSaleOfNetOperatingLosses_iI_pn5n6_c20210930__dei--LegalEntityAxis__custom--JonesTradingInstitutionalServicesLLCMember__us-gaap--TypeOfArrangementAxis__custom--CapitalOnDemandTMSalesAgreementMember_z2SicyjMR9e5" title="Cash and cash equivalents, restricted cash, short-term investments, interest receivable"&gt;60.6&lt;/span&gt; million in cash and cash equivalents, restricted cash, short-term investments
and interest receivable, the Company believes it has sufficient capital resources to fund its operations through the end of 2024.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;The
Company has based its estimates on assumptions that may prove to be wrong. The Company may need to obtain additional funds sooner or
in greater amounts than it currently anticipates. Potential sources of financing include strategic relationships, public or private sales
of the Company&#x2019;s shares or debt, the sale of the Company&#x2019;s State of New Jersey net operating losses and other sources. If
the Company raises funds by selling additional shares of common stock or other securities convertible into common stock, the ownership
interest of existing stockholders may be diluted.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

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    <us-gaap:RetainedEarningsAccumulatedDeficit contextRef="AsOf2021-09-30" decimals="-6" unitRef="USD">-329000000</us-gaap:RetainedEarningsAccumulatedDeficit>
    <CLSN:CashAndCashEquivalentsRestrictedCashShorttermInvestmentsAndReceivableOnSaleOfNetOperatingLosses contextRef="AsOf2021-09-30" decimals="-5" unitRef="USD">60600000</CLSN:CashAndCashEquivalentsRestrictedCashShorttermInvestmentsAndReceivableOnSaleOfNetOperatingLosses>
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    <CLSN:NetProceedsFromSaleOfNetOperatingLosses
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    <us-gaap:DebtInstrumentDescription contextRef="From2021-01-012021-09-30_custom_SVBLoanFacilityMember">Payments under the
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    <us-gaap:DebtInstrumentInterestRateStatedPercentage
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    <CLSN:PaymentOfDebtEndTermCharges
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      unitRef="USD">200000</CLSN:PaymentOfDebtEndTermCharges>
    <us-gaap:DebtInstrumentFaceAmount
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    <us-gaap:LineOfCreditFacilityMaximumBorrowingCapacity
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    <CLSN:RepaymentOfOutstandingIndebtednessAmount
      contextRef="AsOf2021-09-30_custom_HorizonTechnologyFinanceCorporationMember_custom_SVBLoanFacilityMember"
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    <us-gaap:LineOfCreditFacilityRemainingBorrowingCapacity
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      contextRef="AsOf2021-09-30_custom_SiliconValleyBankMember_us-gaap_PrimeRateMember_custom_SVBLoanFacilityMember"
      decimals="INF"
      unitRef="Pure">0.0325</us-gaap:DebtInstrumentInterestRateStatedPercentage>
    <us-gaap:ProceedsFromContributedCapital
      contextRef="From2021-03-172021-03-19_custom_CapitalOnDemandTMSalesAgreementMember_custom_JonesTradingInstitutionalServicesLLCMember"
      decimals="-5"
      unitRef="USD">6900000</us-gaap:ProceedsFromContributedCapital>
    <us-gaap:DebtInstrumentFaceAmount
      contextRef="AsOf2021-01-31_custom_CapitalOnDemandTMSalesAgreementMember_custom_JonesTradingInstitutionalServicesLLCMember"
      decimals="-6"
      unitRef="USD">35000000</us-gaap:DebtInstrumentFaceAmount>
    <us-gaap:DebtInstrumentFaceAmount
      contextRef="AsOf2021-04-05_custom_CapitalOnDemandTMSalesAgreementMember_custom_JonesTradingInstitutionalServicesLLCMember"
      decimals="-6"
      unitRef="USD">15000000</us-gaap:DebtInstrumentFaceAmount>
    <us-gaap:ProceedsFromWarrantExercises
      contextRef="From2021-01-012021-01-31_custom_CapitalOnDemandTMSalesAgreementMember_custom_JonesTradingInstitutionalServicesLLCMember"
      decimals="-5"
      unitRef="USD">1500000</us-gaap:ProceedsFromWarrantExercises>
    <CLSN:CashAndCashEquivalentsRestrictedCashShorttermInvestmentsAndReceivableOnSaleOfNetOperatingLosses
      contextRef="AsOf2021-09-30_custom_JonesTradingInstitutionalServicesLLCMember_custom_CapitalOnDemandTMSalesAgreementMember"
      decimals="-5"
      unitRef="USD">60600000</CLSN:CashAndCashEquivalentsRestrictedCashShorttermInvestmentsAndReceivableOnSaleOfNetOperatingLosses>
    <us-gaap:NewAccountingPronouncementsAndChangesInAccountingPrinciplesTextBlock contextRef="From2021-01-01to2021-09-30">&lt;p id="xdx_803_eus-gaap--NewAccountingPronouncementsAndChangesInAccountingPrinciplesTextBlock_zRdTbb9GOu0h" style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Note
4. &lt;span id="xdx_82B_z2MozqO6ROFd"&gt;New Accounting Pronouncements&lt;/span&gt;&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;From
time to time, new accounting pronouncements are issued by the Financial Accounting Standards Board (FASB) and are adopted by us as of
the specified effective date. Unless otherwise discussed, we believe that the impact of recently issued accounting pronouncements will
not have a material impact on the Company&#x2019;s condensed consolidated financial position, results of operations, and cash flows, or
do not apply to our operations.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;In
June 2016, the FASB issued ASU No. 2016-13, &lt;i&gt;&#x201c;Financial Instruments &#x2013; Credit Losses (Topic 326): Measurement of Credit
Losses on Financial Instruments&#x201d;&lt;/i&gt;, which modifies the measurement of expected credit losses on certain financial instruments.
The Company adopted ASU 2016-13 in the first quarter of 2021 utilizing the modified retrospective transition method. Based on the composition
of the Company&#x2019;s investment portfolio and current market conditions, the adoption of ASU 2016-13 did not have a material impact
on its consolidated financial statements.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;In
December 2019, the FASB issued ASU No. 2019-12, &lt;i&gt;Income Taxes (Topic 740)&lt;/i&gt;. The standard simplifies the accounting for incomes taxes
by removing certain exceptions to the general principles in Topic 740 related to the approach for intra-period tax allocation and the
recognition of deferred tax liabilities for outside basis differences. The standard also clarifies the accounting for transactions that
result in a step-up in the tax basis of goodwill. The standard also improves consistent application of and simplifies GAAP for other
areas of Topic 740 by clarifying and amending existing guidance. The amendment is effective for fiscal years, and interim periods within
those fiscal years, beginning after December 15, 2020. The Company adopted this standard during the first quarter of 2021. The adoption
of ASU 2019-12 did not have a material impact on its consolidated financial statements.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;In
connection with the upcoming elimination of the London Inter-bank Offered Rate, (&#x201c;LIBOR&#x201d;) and other reference interest rates,
the FASB issued ASU 2020-04, &lt;i&gt;Reference Rate Reform (Topic 848) Facilitation of the Effects of Reference Reform on Financial Reporting&lt;/i&gt;.
ASU 2020-04, which is available for contract modifications and hedging relationship modifications entered into or evaluated before December
31, 2022, provides certain practical expedients related to simplifying the accounting for contract modifications resulting from the change
in terms from LIBOR to a new required interest rate benchmark. The Company is currently evaluating the effects of adopting this accounting
standards update.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"/&gt;



&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"/&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;In
May 2021, the FASB issued ASU No. 2021-04 &#x201c;&lt;i&gt;Earnings Per Share (Topic 260), Debt-Modifications and Extinguishments (Subtopic
470-50), Compensation-Stock Compensation (Topic 718), and Derivatives and Hedging-Contracts in Entity&#x2019;s Own Equity (Subtopic 815-40):
Issuer&#x2019;s Accounting for Certain Modifications or Exchanges of Freestanding Equity-Classified Written Call Options (a consensus
of the FASB Emerging Issues Task Force)&#x201d;. &lt;/i&gt;This ASU is intended to clarify and reduce diversity in an issuer&#x2019;s accounting
for modifications or exchanges of freestanding equity-classified written call options (for example, warrants) that remain equity classified
after modification or exchange. The guidance clarifies whether an issuer should account for a modification or an exchange of a freestanding
equity-classified written call option that remains equity classified after modification or exchange as (1) an adjustment to equity and,
if so, the related earnings per share effects, if any, or (2) an expense and, if so, the manner and pattern of recognition. The amendments
in this ASU affect all entities that issue freestanding written call options that are classified in equity. The amendments do not apply
to modifications or exchanges of financial instruments that are within the scope of another Topic and do not affect a holder&#x2019;s
accounting for freestanding call options. The amendments in this ASU are effective for all entities for fiscal years beginning after
December 15, 2021, including interim periods within those fiscal years. An entity should apply the amendments prospectively to modifications
or exchanges occurring on or after the effective date of the amendments. Early adoption is permitted for all entities, including adoption
in an interim period. The Company is currently evaluating the impact of adopting ASU 2021-04 on its consolidated financial statements.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

</us-gaap:NewAccountingPronouncementsAndChangesInAccountingPrinciplesTextBlock>
    <us-gaap:RestrictedAssetsDisclosureTextBlock contextRef="From2021-01-01to2021-09-30">&lt;p id="xdx_804_eus-gaap--RestrictedAssetsDisclosureTextBlock_zuOk9WXXkaUc" style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Note
5. &lt;span id="xdx_822_zXldshkScDT3"&gt;Restricted Cash&lt;/span&gt;&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;As
a condition of the $&lt;span id="xdx_90E_eus-gaap--LineOfCreditFacilityMaximumBorrowingCapacity_iI_pn6n6_c20210930__us-gaap--RelatedPartyTransactionsByRelatedPartyAxis__custom--SiliconValleyBankMember__us-gaap--TypeOfArrangementAxis__custom--SVBLoanFacilityMember_zqgY3uLQt7fd"&gt;10
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million loan facility with Silicon Valley Bank
(&#x201c;SVB&#x201d;) entered into on June 18, 2021 as further discussed in Note 11, &lt;span id="xdx_90C_eus-gaap--LineOfCreditFacilityDescription_c20210601__20210618__us-gaap--TypeOfArrangementAxis__custom--SVBLoanFacilityMember"&gt;the
Company is required at all times to maintain on deposit with SVB as cash collateral in a segregated money market bank account in the
name of the Company, unrestricted and unencumbered cash (other than a lien in favor of SVB) in an amount of at least 100% of the
aggregate outstanding amount of the SVB loan facility. SVB may restrict withdrawals or transfers by or on behalf of the Company that
would violate this requirement.&lt;/span&gt;&lt;/span&gt; &lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;The required reserve
totaled $&lt;span id="xdx_90C_eus-gaap--RestrictedInvestments_c20210930__us-gaap--RelatedPartyTransactionsByRelatedPartyAxis__custom--SiliconValleyBankMember__us-gaap--TypeOfArrangementAxis__custom--SVBLoanFacilityMember_pn5n6"&gt;6.0
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million as of September 30, 2021. This amount
is presented in part as restricted cash in other non-current assets on the accompanying condensed consolidated balance sheets.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p id="xdx_89C_eus-gaap--ScheduleOfRestrictedCashAndCashEquivalentsTextBlock_zJcnGDjMtAB4" style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;The
following table reconciles cash and cash equivalents and restricted cash per the balance sheet to the condensed statements of cash flows:&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;span id="xdx_8B6_zZdAaWtmbBM8" style="display: none"&gt;Schedule of Cash and Cash Equivalents and Restricted Cash&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; border-collapse: collapse; width: 100%"&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td&gt;&#160;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" id="xdx_49A_20210930_z9QVJM1etSre" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;September 30, 2021&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&#160;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" id="xdx_490_20200930_ztUIdPC1fzeh" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;September 30, 2020&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_40E_eus-gaap--CashAndCashEquivalentsAtCarryingValue_iI_pp0p0_maCCERCzBMn_zu3AnaAnsAS6" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="width: 60%; text-align: left"&gt;Cash and cash equivalents&lt;/td&gt;&lt;td style="width: 2%"&gt;&#160;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;$&lt;/td&gt;&lt;td style="width: 16%; text-align: right"&gt;25,648,849&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="width: 2%"&gt;&#160;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;$&lt;/td&gt;&lt;td style="width: 16%; text-align: right"&gt;18,339,728&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_40E_eus-gaap--RestrictedInvestments_iI_pp0p0_maCCERCzBMn_zPQaOGGA20j3" style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left; padding-bottom: 1.5pt"&gt;Money market investments, restricted&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="border-bottom: Black 1.5pt solid; text-align: right"&gt;6,000,000&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0862"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="border-bottom: Black 1.5pt solid; text-align: right"&gt;-&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_406_eus-gaap--CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_iTI_pp0p0_mtCCERCzBMn_zFbGBRoGvdf2" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="padding-left: 10pt; padding-bottom: 2.5pt"&gt;Total&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;$&lt;/td&gt;&lt;td style="border-bottom: Black 2.5pt double; text-align: right"&gt;31,648,849&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;$&lt;/td&gt;&lt;td style="border-bottom: Black 2.5pt double; text-align: right"&gt;18,339,728&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;

&lt;p id="xdx_8A6_zkPbT9NLNy4a" style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

</us-gaap:RestrictedAssetsDisclosureTextBlock>
    <us-gaap:LineOfCreditFacilityMaximumBorrowingCapacity
      contextRef="AsOf2021-09-30_custom_SiliconValleyBankMember_custom_SVBLoanFacilityMember"
      decimals="-6"
      unitRef="USD">10000000</us-gaap:LineOfCreditFacilityMaximumBorrowingCapacity>
    <us-gaap:LineOfCreditFacilityDescription contextRef="From2021-06-012021-06-18_custom_SVBLoanFacilityMember">the
Company is required at all times to maintain on deposit with SVB as cash collateral in a segregated money market bank account in the
name of the Company, unrestricted and unencumbered cash (other than a lien in favor of SVB) in an amount of at least 100% of the
aggregate outstanding amount of the SVB loan facility. SVB may restrict withdrawals or transfers by or on behalf of the Company that
would violate this requirement.</us-gaap:LineOfCreditFacilityDescription>
    <us-gaap:RestrictedInvestments
      contextRef="AsOf2021-09-30_custom_SiliconValleyBankMember_custom_SVBLoanFacilityMember"
      decimals="-5"
      unitRef="USD">6000000.0</us-gaap:RestrictedInvestments>
    <us-gaap:ScheduleOfRestrictedCashAndCashEquivalentsTextBlock contextRef="From2021-01-01to2021-09-30">&lt;p id="xdx_89C_eus-gaap--ScheduleOfRestrictedCashAndCashEquivalentsTextBlock_zJcnGDjMtAB4" style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;The
following table reconciles cash and cash equivalents and restricted cash per the balance sheet to the condensed statements of cash flows:&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;span id="xdx_8B6_zZdAaWtmbBM8" style="display: none"&gt;Schedule of Cash and Cash Equivalents and Restricted Cash&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; border-collapse: collapse; width: 100%"&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td&gt;&#160;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" id="xdx_49A_20210930_z9QVJM1etSre" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;September 30, 2021&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&#160;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" id="xdx_490_20200930_ztUIdPC1fzeh" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;September 30, 2020&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_40E_eus-gaap--CashAndCashEquivalentsAtCarryingValue_iI_pp0p0_maCCERCzBMn_zu3AnaAnsAS6" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="width: 60%; text-align: left"&gt;Cash and cash equivalents&lt;/td&gt;&lt;td style="width: 2%"&gt;&#160;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;$&lt;/td&gt;&lt;td style="width: 16%; text-align: right"&gt;25,648,849&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="width: 2%"&gt;&#160;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;$&lt;/td&gt;&lt;td style="width: 16%; text-align: right"&gt;18,339,728&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_40E_eus-gaap--RestrictedInvestments_iI_pp0p0_maCCERCzBMn_zPQaOGGA20j3" style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left; padding-bottom: 1.5pt"&gt;Money market investments, restricted&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="border-bottom: Black 1.5pt solid; text-align: right"&gt;6,000,000&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0862"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="border-bottom: Black 1.5pt solid; text-align: right"&gt;-&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_406_eus-gaap--CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_iTI_pp0p0_mtCCERCzBMn_zFbGBRoGvdf2" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="padding-left: 10pt; padding-bottom: 2.5pt"&gt;Total&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;$&lt;/td&gt;&lt;td style="border-bottom: Black 2.5pt double; text-align: right"&gt;31,648,849&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;$&lt;/td&gt;&lt;td style="border-bottom: Black 2.5pt double; text-align: right"&gt;18,339,728&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;

</us-gaap:ScheduleOfRestrictedCashAndCashEquivalentsTextBlock>
    <us-gaap:CashAndCashEquivalentsAtCarryingValue contextRef="AsOf2021-09-30" decimals="0" unitRef="USD">25648849</us-gaap:CashAndCashEquivalentsAtCarryingValue>
    <us-gaap:CashAndCashEquivalentsAtCarryingValue contextRef="AsOf2020-09-30" decimals="0" unitRef="USD">18339728</us-gaap:CashAndCashEquivalentsAtCarryingValue>
    <us-gaap:RestrictedInvestments contextRef="AsOf2021-09-30" decimals="0" unitRef="USD">6000000</us-gaap:RestrictedInvestments>
    <us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents contextRef="AsOf2021-09-30" decimals="0" unitRef="USD">31648849</us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents>
    <us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents contextRef="AsOf2020-09-30" decimals="0" unitRef="USD">18339728</us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents>
    <us-gaap:EarningsPerShareTextBlock contextRef="From2021-01-01to2021-09-30">&lt;p id="xdx_80D_eus-gaap--EarningsPerShareTextBlock_znsNWcuTpBu3" style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Note
6. &lt;span id="xdx_821_zuMSgV83CQIj"&gt;Net Loss per Common Share&lt;/span&gt;&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Basic
loss per share is calculated based upon the net loss available to common shareholders divided by the weighted average number of common
shares outstanding during the period. Diluted loss per share is calculated after adjusting the denominator of the basic earnings per
share computation for the effects of all dilutive potential common shares outstanding during the period. The dilutive effects of preferred
stock, options and warrants and their equivalents are computed using the treasury stock method.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;The
total number of shares of common stock issuable upon exercise of warrants, stock option grants and equity awards were &lt;span id="xdx_907_ecustom--NumberOfSharesOfCommonStockIssuableUponExerciseOfWarrantsAndEquityAwards_c20210101__20210930_zz3caWBjp2Ib" title="Shares of common stock issuable upon exercise of warrants and equity awards"&gt;9,250,354&lt;/span&gt; and &lt;span id="xdx_905_ecustom--NumberOfSharesOfCommonStockIssuableUponExerciseOfWarrantsAndEquityAwards_c20200101__20200930_zGyt5FRxIQv8" title="Shares of common stock issuable upon exercise of warrants and equity awards"&gt;8,507,041&lt;/span&gt;
shares for the three-month and nine-month periods ended September 30, 2021 and 2020, respectively. Warrants with an exercise price of
$&lt;span id="xdx_902_eus-gaap--ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1_c20210930_pdd" title="Class of Warrant or Right, Exercise Price of Warrants or Rights"&gt;0.01&lt;/span&gt; exercisable for &lt;span id="xdx_904_ecustom--NumberOfSharesOfCommonStockIssuedInCalculationBasicLossPerShare_c20200101__20200930_zNi9MGAvvKV5" title="Number of shares of common stock issued in calculation basic loss per share"&gt;200,000&lt;/span&gt; shares of common stock were considered issued in calculating basic loss per share during the first nine-months
of 2020. These warrants were exercised in October 2020. For the three-month and nine-month periods ended September 30, 2021 and 2020,
diluted loss per common share was the same as basic loss per common share as the other warrants and equity awards that were convertible
into shares of the Company&#x2019;s common stock were excluded from the calculation of diluted loss per common share as their effect would
have been anti-dilutive. The Company did not pay any dividends during the first nine months of 2021 or 2020.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

</us-gaap:EarningsPerShareTextBlock>
    <CLSN:NumberOfSharesOfCommonStockIssuableUponExerciseOfWarrantsAndEquityAwards
      contextRef="From2021-01-01to2021-09-30"
      decimals="INF"
      unitRef="Shares">9250354</CLSN:NumberOfSharesOfCommonStockIssuableUponExerciseOfWarrantsAndEquityAwards>
    <CLSN:NumberOfSharesOfCommonStockIssuableUponExerciseOfWarrantsAndEquityAwards
      contextRef="From2020-01-012020-09-30"
      decimals="INF"
      unitRef="Shares">8507041</CLSN:NumberOfSharesOfCommonStockIssuableUponExerciseOfWarrantsAndEquityAwards>
    <us-gaap:ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1
      contextRef="AsOf2021-09-30"
      decimals="INF"
      unitRef="USDPShares">0.01</us-gaap:ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1>
    <CLSN:NumberOfSharesOfCommonStockIssuedInCalculationBasicLossPerShare
      contextRef="From2020-01-012020-09-30"
      decimals="INF"
      unitRef="Shares">200000</CLSN:NumberOfSharesOfCommonStockIssuedInCalculationBasicLossPerShare>
    <us-gaap:InvestmentsInDebtAndMarketableEquitySecuritiesAndCertainTradingAssetsDisclosureTextBlock contextRef="From2021-01-01to2021-09-30">&lt;p id="xdx_806_eus-gaap--InvestmentsInDebtAndMarketableEquitySecuritiesAndCertainTradingAssetsDisclosureTextBlock_z7pouDRu6Pz6" style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Note
7. &lt;span id="xdx_821_ztPGJYVM0Phj"&gt;Investment in Debt Securities-Available for Sale&lt;/span&gt;&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Investments
in debt securities available for sale with a fair value of $&lt;span id="xdx_902_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_c20210930_pp0p0" title="Debt Securities, Available-for-sale, Current"&gt;28,864,364&lt;/span&gt; as of September 30, 2021, consisted of government backed debt
securities and commercial paper. These investments are valued at estimated fair value, with unrealized gains and losses reported as a
separate component of stockholders&#x2019; equity in accumulated other comprehensive loss. The Company only had investments in cash and
cash equivalents on December 31, 2020.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Investments
in debt securities available for sale are evaluated periodically to determine whether a decline in their value is other than temporary.
The term &#x201c;other than temporary&#x201d; is not intended to indicate a permanent decline in value. Rather, it means that the prospects
for near term recovery of value are not necessarily favorable, or that there is a lack of evidence to support fair values equal to, or
greater than, the carrying value of the security. Management reviews criteria such as the magnitude and duration of the decline, as well
as the reasons for the decline, to predict whether the loss in value is other than temporary. Once a decline in value is determined to
be other than temporary, the value of the security is reduced and a corresponding charge to earnings is recognized.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"/&gt;



&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p id="xdx_89F_eus-gaap--DebtSecuritiesAvailableForSaleTableTextBlock_zzq0nSfTaJmb" style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;A
summary of the cost, fair value and maturities of the Company&#x2019;s short-term investments is as follows:&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;span id="xdx_8B0_zV1ZrZRQn4v9" style="display: none"&gt;Schedule of Cost, Fair Value and Maturities of Short Term Investments&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"/&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; border-collapse: collapse; width: 100%"&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: bottom"&gt;
    &lt;td style="font: bold 10pt Times New Roman, Times, Serif; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="6" style="border-bottom: Black 1.5pt solid; font: bold 10pt Times New Roman, Times, Serif; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;September
    30, 2021&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="6" style="border-bottom: Black 1.5pt solid; font: bold 10pt Times New Roman, Times, Serif; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;December
    31, 2020&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: bottom"&gt;
    &lt;td style="font: bold 10pt Times New Roman, Times, Serif; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font: bold 10pt Times New Roman, Times, Serif; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Cost&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font: bold 10pt Times New Roman, Times, Serif; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Fair
    Value&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font: bold 10pt Times New Roman, Times, Serif; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Cost&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font: bold 10pt Times New Roman, Times, Serif; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Fair
    Value&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="font: bold 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Short-term
    investments&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: right"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: right"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: right"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: right"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: bottom; background-color: White"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; width: 44%; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Commercial
    paper&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; width: 2%"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; width: 1%; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98A_eus-gaap--ShortTermInvestments_iI_pp0p0_c20210930__us-gaap--FinancialInstrumentAxis__us-gaap--CommercialPaperMember_zad35p3zWY73" style="font: 10pt Times New Roman, Times, Serif; width: 10%; text-align: right" title="Short-term investments - Cost"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;7,784,165&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; width: 1%; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; width: 2%"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; width: 1%; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_982_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_iI_pp0p0_c20210930__us-gaap--FinancialInstrumentAxis__us-gaap--CommercialPaperMember_zf2grA15hsHi" style="font: 10pt Times New Roman, Times, Serif; width: 10%; text-align: right" title="Short-term investments - Fair Value"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;7,784,894&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; width: 1%; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; width: 2%"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; width: 1%; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98D_eus-gaap--ShortTermInvestments_iI_pp0p0_c20201231__us-gaap--FinancialInstrumentAxis__us-gaap--CommercialPaperMember_zuYnRYmYR4nf" style="font: 10pt Times New Roman, Times, Serif; width: 10%; text-align: right" title="Short-term investments - Cost"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0887"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; width: 1%; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; width: 2%"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; width: 1%; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98C_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_iI_pp0p0_c20201231__us-gaap--FinancialInstrumentAxis__us-gaap--CommercialPaperMember_zKMkHWCM26A6" style="font: 10pt Times New Roman, Times, Serif; width: 10%; text-align: right" title="Short-term investments - Fair Value"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0889"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; width: 1%; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: left; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Government
    backed debt securities&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98F_eus-gaap--ShortTermInvestments_iI_pp0p0_c20210930__us-gaap--FinancialInstrumentAxis__custom--GovernmentBackedDebtSecuritiesMember_zPorrtjPk0u2" style="border-bottom: Black 1.5pt solid; font: 10pt Times New Roman, Times, Serif; text-align: right" title="Short-term investments - Cost"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;21,078,059&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98D_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_iI_pp0p0_c20210930__us-gaap--FinancialInstrumentAxis__custom--GovernmentBackedDebtSecuritiesMember_zHDhMtVpFyW1" style="border-bottom: Black 1.5pt solid; font: 10pt Times New Roman, Times, Serif; text-align: right" title="Short-term investments - Fair Value"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;21,079,470&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98C_eus-gaap--ShortTermInvestments_iI_pp0p0_c20201231__us-gaap--FinancialInstrumentAxis__custom--GovernmentBackedDebtSecuritiesMember_z54kt7d802E9" style="border-bottom: Black 1.5pt solid; font: 10pt Times New Roman, Times, Serif; text-align: right" title="Short-term investments - Cost"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0895"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_983_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_iI_pp0p0_c20201231__us-gaap--FinancialInstrumentAxis__custom--GovernmentBackedDebtSecuritiesMember_z43dcqp5k29h" style="border-bottom: Black 1.5pt solid; font: 10pt Times New Roman, Times, Serif; text-align: right" title="Short-term investments - Fair Value"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0897"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: bottom; background-color: White"&gt;
    &lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 2.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Total&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 2.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98D_eus-gaap--ShortTermInvestments_iI_pp0p0_c20210930_zCItIYAKCDS6" style="border-bottom: Black 2.5pt double; font: 10pt Times New Roman, Times, Serif; text-align: right" title="Short-term investments - Cost"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;28,862,224&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 2.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_985_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_iI_pp0p0_c20210930_zPjVplVgCeV2" style="border-bottom: Black 2.5pt double; font: 10pt Times New Roman, Times, Serif; text-align: right" title="Short-term investments - Fair Value"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;28,864,364&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 2.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_981_eus-gaap--ShortTermInvestments_iI_pp0p0_c20201231_zwdScDeyVgIc" style="border-bottom: Black 2.5pt double; font: 10pt Times New Roman, Times, Serif; text-align: right" title="Short-term investments - Cost"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0903"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 2.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98F_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_iI_pp0p0_c20201231_z5PkYsoXcaB1" style="border-bottom: Black 2.5pt double; font: 10pt Times New Roman, Times, Serif; text-align: right" title="Short-term investments - Fair Value"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0905"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; border-collapse: collapse; width: 100%"&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: bottom"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="6" style="border-bottom: Black 1.5pt solid; font: bold 10pt Times New Roman, Times, Serif; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;September
    30, 2021&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="6" style="border-bottom: Black 1.5pt solid; font: bold 10pt Times New Roman, Times, Serif; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;December
    31, 2020&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: bottom"&gt;
    &lt;td style="font: bold 10pt Times New Roman, Times, Serif; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font: bold 10pt Times New Roman, Times, Serif; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Cost&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font: bold 10pt Times New Roman, Times, Serif; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Fair
    Value&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font: bold 10pt Times New Roman, Times, Serif; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Cost&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font: bold 10pt Times New Roman, Times, Serif; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Fair
    Value&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="font: bold 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Short-term
    investment maturities&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: bold 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; text-align: right"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: bold 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; text-align: right"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: bold 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; text-align: right"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: bold 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; text-align: right"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: bottom; background-color: White"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; width: 44%"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Within
    3 months&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; width: 2%"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; width: 1%; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_983_ecustom--DebtSecuritiesAvailableforsaleMaturityAllocatedAndSingleMaturityDateRollingWithinThreeMonthsAmortizedCost_iI_pp0p0_c20210930_zS3J46fRddI5" style="font: 10pt Times New Roman, Times, Serif; width: 10%; text-align: right" title="Short-term investment maturities - Within 3 months, cost"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;11,998,304&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; width: 1%; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; width: 2%"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; width: 1%; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_987_ecustom--DebtSecuritiesAvailableforsaleMaturityAllocatedAndSingleMaturityDateRollingWithinThreeMonthsFairValue_iI_pp0p0_c20210930_z22mquKJYY0b" style="font: 10pt Times New Roman, Times, Serif; width: 10%; text-align: right" title="Short-term investment maturities - Within 3 months, fair value"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;11,999,400&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; width: 1%; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; width: 2%"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; width: 1%; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_982_ecustom--DebtSecuritiesAvailableforsaleMaturityAllocatedAndSingleMaturityDateRollingWithinThreeMonthsAmortizedCost_iI_pp0p0_c20201231_z9zmhKylkTr7" style="font: 10pt Times New Roman, Times, Serif; width: 10%; text-align: right" title="Short-term investment maturities - Within 3 months, cost"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0911"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; width: 1%; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; width: 2%"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; width: 1%; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_987_ecustom--DebtSecuritiesAvailableforsaleMaturityAllocatedAndSingleMaturityDateRollingWithinThreeMonthsFairValue_iI_pp0p0_c20201231_zGHosuu1zqvl" style="font: 10pt Times New Roman, Times, Serif; width: 10%; text-align: right" title="Short-term investment maturities - Within 3 months, fair value"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0913"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; width: 1%; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Between
    3-12 months&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98C_ecustom--DebtSecuritiesAvailableforsaleMaturityAllocatedAndSingleMaturityDateRollingBetweenThreeAndTwelveMonthsAmortizedCost_iI_pp0p0_c20210930_zpsqJ1z2Udga" style="border-bottom: Black 1.5pt solid; font: 10pt Times New Roman, Times, Serif; text-align: right" title="Short-term investment maturities - Between 3-12 months, cost"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;16,863,920&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98B_ecustom--DebtSecuritiesAvailableforsaleMaturityAllocatedAndSingleMaturityDateRollingBetweenThreeAndTwelveMonthsFairValue_iI_pp0p0_c20210930_zqbNZhL02jEf" style="border-bottom: Black 1.5pt solid; font: 10pt Times New Roman, Times, Serif; text-align: right" title="Short-term investment maturities - Between 3-12 months, fair value"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;16,864,964&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_980_eus-gaap--ShortTermInvestments_iI_pp0p0_c20201230_zCsx26sB427j" style="border-bottom: Black 1.5pt solid; font: 10pt Times New Roman, Times, Serif; text-align: right" title="Short-term investment maturities - Between 3-12 months, cost"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0919"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_988_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_iI_pp0p0_c20201231__us-gaap--FinancialInstrumentAxis__custom--GovernmentBackedDebtSecuritiesMember_z5iBqFQluvf" style="border-bottom: Black 1.5pt solid; font: 10pt Times New Roman, Times, Serif; text-align: right" title="Short-term investment maturities - Between 3-12 months, fair value"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0921"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: bottom; background-color: White"&gt;
    &lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 2.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Total&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 2.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_982_ecustom--AvailableForSaleDebtSecuritiesAmortizedCostBasisCurrent_iI_pp0p0_c20210930_zQ5Pg4fmo4w6" style="border-bottom: Black 2.5pt double; font: 10pt Times New Roman, Times, Serif; text-align: right" title="Total, cost"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;28,862,224&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 2.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_980_eus-gaap--AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDate_iI_pp0p0_c20210930_zPCf5TMFwaJj" style="border-bottom: Black 2.5pt double; font: 10pt Times New Roman, Times, Serif; text-align: right" title="Total, fair value"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;28,864,364&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 2.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_987_ecustom--AvailableForSaleDebtSecuritiesAmortizedCostBasisCurrent_iI_pp0p0_c20201231_zKdYKTCgLVIj" style="border-bottom: Black 2.5pt double; font: 10pt Times New Roman, Times, Serif; text-align: right" title="Total, cost"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0927"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 2.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_985_eus-gaap--AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDate_iI_pp0p0_c20201231_z1xCqLLROCDc" style="border-bottom: Black 2.5pt double; font: 10pt Times New Roman, Times, Serif; text-align: right" title="Total, fair value"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0929"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;

&lt;p id="xdx_8A6_zNMonONGCt56" style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p id="xdx_89F_eus-gaap--ScheduleOfUnrealizedLossOnInvestmentsTableTextBlock_z4H6v74WqIf2" style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;The
following table shows the Company&#x2019;s investment in debt securities available for sale gross unrealized gains (losses) and fair value
by investment category and length of time that individual securities have been in a continuous unrealized loss position at September
30, 2021 and December 31, 2020. The Company has reviewed individual securities to determine whether a decline in fair value below the
amortizable cost basis is other than temporary.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;span id="xdx_8BE_z9xo3x4iTPS5" style="display: none"&gt;Summary of Investment Securities Gross Unrealized Gains (Losses)&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"/&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; border-collapse: collapse; width: 100%"&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: bottom"&gt;
    &lt;td style="font: bold 10pt Times New Roman, Times, Serif; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="6" style="border-bottom: Black 1.5pt solid; font: bold 10pt Times New Roman, Times, Serif; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;September
    30, 2021&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="6" style="border-bottom: Black 1.5pt solid; font: bold 10pt Times New Roman, Times, Serif; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;December
    31, 2020&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: bottom"&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; font: bold 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Available
    for sale securities (all unrealized holding gains and losses are less than 12 months at date of measurement)&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font: bold 10pt Times New Roman, Times, Serif; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Fair
    Value&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font: 10pt Times New Roman, Times, Serif; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Unrealized
                                            Holding&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Gains
                                            (Losses)&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font: bold 10pt Times New Roman, Times, Serif; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Fair
    Value&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font: 10pt Times New Roman, Times, Serif; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Unrealized
                                            Holding&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Gains
                                            (Losses)&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: bottom"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="font: 10pt Times New Roman, Times, Serif; text-align: right"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="font: 10pt Times New Roman, Times, Serif; text-align: right"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="font: 10pt Times New Roman, Times, Serif; text-align: right"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="font: 10pt Times New Roman, Times, Serif; text-align: right"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; width: 44%; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Investments
    with unrealized gains&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; width: 2%"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; width: 1%; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98B_ecustom--AvailableForSaleSecuritiesUnrealizedGainsFairValue_iI_c20210930_zZFBcSNgdmJg" style="font: 10pt Times New Roman, Times, Serif; width: 10%; text-align: right" title="Investments with unrealized gains, Fair Value"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;21,029,520&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; width: 1%; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; width: 2%"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; width: 1%; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_980_ecustom--AvailableForSaleSecuritiesUnrealizedHoldingGainsLessThanTwelveMonths_iI_c20210930_zJYhdCRAaGdj" style="font: 10pt Times New Roman, Times, Serif; width: 10%; text-align: right" title="Investments with unrealized gains, Unrealized Holding Gains (Losses)"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;3,055&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; width: 1%; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; width: 2%"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; width: 1%; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98E_ecustom--AvailableForSaleSecuritiesUnrealizedGainsFairValue_iI_c20201231_z3M02uua3jil" style="font: 10pt Times New Roman, Times, Serif; width: 10%; text-align: right"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0936"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; width: 1%; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; width: 2%"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; width: 1%; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_982_ecustom--AvailableForSaleSecuritiesUnrealizedHoldingGainsLessThanTwelveMonths_iI_c20201231_zCpfoZv0DlK1" style="font: 10pt Times New Roman, Times, Serif; width: 10%; text-align: right" title="Investments with unrealized gains, Unrealized Holding Gains (Losses)"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0938"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; width: 1%; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: bottom; background-color: White"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: left; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Investments
    with unrealized losses&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_988_ecustom--AvailableForSaleSecuritiesUnrealizedLossFairValue_iI_c20210930_zO7ZcWPmC50l" style="border-bottom: Black 1.5pt solid; font: 10pt Times New Roman, Times, Serif; text-align: right" title="Investments with unrealized losses, Fair Value"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;7,834,844&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98A_ecustom--AvailableForSaleSecuritiesUnrealizedHoldingLossesLessThanTwelveMonths_iI_c20210930_zmB303ynsmW1" style="border-bottom: Black 1.5pt solid; font: 10pt Times New Roman, Times, Serif; text-align: right" title="Investments with unrealized Losses, Unrealized Holding Gains (Losses)"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;(916&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;)&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_980_ecustom--AvailableForSaleSecuritiesUnrealizedLossFairValue_iI_c20201231_zNVoVOYE8gWa" style="border-bottom: Black 1.5pt solid; font: 10pt Times New Roman, Times, Serif; text-align: right"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0943"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98D_ecustom--AvailableForSaleSecuritiesUnrealizedHoldingLossesLessThanTwelveMonths_iI_c20201231_z5YfLBoPLSs5" style="border-bottom: Black 1.5pt solid; font: 10pt Times New Roman, Times, Serif; text-align: right" title="Investments with unrealized Losses, Unrealized Holding Gains (Losses)"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0945"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 2.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Total&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 2.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_988_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_iI_c20210930_zJlh7KxBeonf" style="border-bottom: Black 2.5pt double; font: 10pt Times New Roman, Times, Serif; text-align: right" title="Investment securities, available for sale"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;28,864,364&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 2.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_981_ecustom--AvailableForSaleSecuritiesUnrealizedHoldingGainsLossesLessThanTwelveMonths_iI_c20210930_zAbpPPg8pkJ5" style="border-bottom: Black 2.5pt double; font: 10pt Times New Roman, Times, Serif; text-align: right" title="Investments with unrealized Gains (Losses), Unrealized Holding Gains (Losses)"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;2,139&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 2.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98E_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_iI_pp0p0_c20201231_zb9V7QrzJGT5" style="border-bottom: Black 2.5pt double; font: 10pt Times New Roman, Times, Serif; text-align: right"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0950"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 2.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_982_ecustom--AvailableForSaleSecuritiesUnrealizedHoldingGainsLossesLessThanTwelveMonths_iI_c20201231_zqL2gyJgazK2" style="border-bottom: Black 2.5pt double; font: 10pt Times New Roman, Times, Serif; text-align: right" title="Investments with unrealized Gains (Losses), Unrealized Holding Gains (Losses)"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0952"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;

&lt;p id="xdx_8AF_zJhKMKRQK2zg" style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p id="xdx_897_eus-gaap--InvestmentIncomeTextBlock_zHJyvcuTyiSh" style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Investment
(loss) income, which includes net realized losses on sales of available for sale securities and investment income interest and dividends,
is summarized as follows:&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;span id="xdx_8B1_z2oGtiDs3Fcf" style="display: none"&gt;Summary of Net Realized Losses on Sales of Available for Sale Securities and Investment Income Interest and Dividends&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; border-collapse: collapse; width: 100%"&gt;
  &lt;tr style="display: none; vertical-align: bottom"&gt;
    &lt;td style="text-align: center"&gt;&#160;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" id="xdx_498_20210701__20210930_zJMMeE8DPxxi" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;2021&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&#160;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" id="xdx_49F_20200701__20200930_zo126XjGm0c9" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;2020&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td style="text-align: center"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="6" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Three Months Ended&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;September 30,&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td style="text-align: center"&gt;&#160;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;2021&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&#160;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;2020&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_401_eus-gaap--InvestmentIncomeInterestAndDividend_maIILNzUXt_zr2HIl3c5Qjl" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="width: 60%; text-align: left"&gt;Interest and dividends accrued and paid&lt;/td&gt;&lt;td style="width: 2%"&gt;&#160;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;$&lt;/td&gt;&lt;td style="width: 16%; text-align: right"&gt;6,288&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="width: 2%"&gt;&#160;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;$&lt;/td&gt;&lt;td style="width: 16%; text-align: right"&gt;2,857&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_40B_eus-gaap--DebtSecuritiesAvailableForSaleRealizedGainLoss_maIILNzUXt_zmMntfnfFmYe" style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left; padding-bottom: 1.5pt"&gt;Realized (losses) gains&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="border-bottom: Black 1.5pt solid; text-align: right"&gt;(2,736&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;)&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="border-bottom: Black 1.5pt solid; text-align: right"&gt;7,257&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_404_ecustom--InvestmentIncomeLossNonoperating_iT_pp0p0_mtIILNzUXt_zk3NkG4XHeza" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left; padding-bottom: 2.5pt"&gt;Investment income, net&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;$&lt;/td&gt;&lt;td style="border-bottom: Black 2.5pt double; text-align: right"&gt;3,552&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;$&lt;/td&gt;&lt;td style="border-bottom: Black 2.5pt double; text-align: right"&gt;10,114&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; border-collapse: collapse; width: 100%"&gt;
  &lt;tr style="display: none; vertical-align: bottom"&gt;
    &lt;td style="text-align: center"&gt;&#160;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" id="xdx_499_20210101__20210930_zODAjUd2SR5d" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;2021&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&#160;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" id="xdx_490_20200101__20200930_z2qBoVdTjcP5" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;2020&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
&lt;tr style="vertical-align: bottom"&gt;
    &lt;td style="text-align: center"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="6" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Nine Months Ended&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;September 30,&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td style="text-align: center"&gt;&#160;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;2021&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&#160;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;2020&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_40E_eus-gaap--InvestmentIncomeInterestAndDividend_maIILNz6Ly_zB02x4Ro85if" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="width: 60%; text-align: left"&gt;Interest and dividends accrued and paid&lt;/td&gt;&lt;td style="width: 2%"&gt;&#160;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;$&lt;/td&gt;&lt;td style="width: 16%; text-align: right"&gt;10,135&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="width: 2%"&gt;&#160;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;$&lt;/td&gt;&lt;td style="width: 16%; text-align: right"&gt;66,029&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_407_eus-gaap--DebtSecuritiesAvailableForSaleRealizedGainLoss_maIILNz6Ly_zGinddnHyn86" style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left; padding-bottom: 1.5pt"&gt;Realized (losses) gains&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="border-bottom: Black 1.5pt solid; text-align: right"&gt;(4,521&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;)&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="border-bottom: Black 1.5pt solid; text-align: right"&gt;53,354&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_402_ecustom--InvestmentIncomeLossNonoperating_iT_pp0p0_mtIILNz6Ly_zlwaaEvIZ3Ag" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left; padding-bottom: 2.5pt"&gt;Investment income, net&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;$&lt;/td&gt;&lt;td style="border-bottom: Black 2.5pt double; text-align: right"&gt;5,614&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;$&lt;/td&gt;&lt;td style="border-bottom: Black 2.5pt double; text-align: right"&gt;119,383&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;

&lt;p id="xdx_8AA_zdNlB6K2mgM" style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

</us-gaap:InvestmentsInDebtAndMarketableEquitySecuritiesAndCertainTradingAssetsDisclosureTextBlock>
    <us-gaap:AvailableForSaleSecuritiesDebtSecuritiesCurrent contextRef="AsOf2021-09-30" decimals="0" unitRef="USD">28864364</us-gaap:AvailableForSaleSecuritiesDebtSecuritiesCurrent>
    <us-gaap:DebtSecuritiesAvailableForSaleTableTextBlock contextRef="From2021-01-01to2021-09-30">&lt;p id="xdx_89F_eus-gaap--DebtSecuritiesAvailableForSaleTableTextBlock_zzq0nSfTaJmb" style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;A
summary of the cost, fair value and maturities of the Company&#x2019;s short-term investments is as follows:&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;span id="xdx_8B0_zV1ZrZRQn4v9" style="display: none"&gt;Schedule of Cost, Fair Value and Maturities of Short Term Investments&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"/&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; border-collapse: collapse; width: 100%"&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: bottom"&gt;
    &lt;td style="font: bold 10pt Times New Roman, Times, Serif; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="6" style="border-bottom: Black 1.5pt solid; font: bold 10pt Times New Roman, Times, Serif; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;September
    30, 2021&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="6" style="border-bottom: Black 1.5pt solid; font: bold 10pt Times New Roman, Times, Serif; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;December
    31, 2020&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: bottom"&gt;
    &lt;td style="font: bold 10pt Times New Roman, Times, Serif; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font: bold 10pt Times New Roman, Times, Serif; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Cost&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font: bold 10pt Times New Roman, Times, Serif; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Fair
    Value&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font: bold 10pt Times New Roman, Times, Serif; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Cost&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font: bold 10pt Times New Roman, Times, Serif; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Fair
    Value&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="font: bold 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Short-term
    investments&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: right"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: right"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: right"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: right"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: bottom; background-color: White"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; width: 44%; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Commercial
    paper&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; width: 2%"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; width: 1%; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98A_eus-gaap--ShortTermInvestments_iI_pp0p0_c20210930__us-gaap--FinancialInstrumentAxis__us-gaap--CommercialPaperMember_zad35p3zWY73" style="font: 10pt Times New Roman, Times, Serif; width: 10%; text-align: right" title="Short-term investments - Cost"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;7,784,165&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; width: 1%; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; width: 2%"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; width: 1%; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_982_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_iI_pp0p0_c20210930__us-gaap--FinancialInstrumentAxis__us-gaap--CommercialPaperMember_zf2grA15hsHi" style="font: 10pt Times New Roman, Times, Serif; width: 10%; text-align: right" title="Short-term investments - Fair Value"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;7,784,894&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; width: 1%; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; width: 2%"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; width: 1%; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98D_eus-gaap--ShortTermInvestments_iI_pp0p0_c20201231__us-gaap--FinancialInstrumentAxis__us-gaap--CommercialPaperMember_zuYnRYmYR4nf" style="font: 10pt Times New Roman, Times, Serif; width: 10%; text-align: right" title="Short-term investments - Cost"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0887"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; width: 1%; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; width: 2%"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; width: 1%; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98C_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_iI_pp0p0_c20201231__us-gaap--FinancialInstrumentAxis__us-gaap--CommercialPaperMember_zKMkHWCM26A6" style="font: 10pt Times New Roman, Times, Serif; width: 10%; text-align: right" title="Short-term investments - Fair Value"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0889"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; width: 1%; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: left; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Government
    backed debt securities&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98F_eus-gaap--ShortTermInvestments_iI_pp0p0_c20210930__us-gaap--FinancialInstrumentAxis__custom--GovernmentBackedDebtSecuritiesMember_zPorrtjPk0u2" style="border-bottom: Black 1.5pt solid; font: 10pt Times New Roman, Times, Serif; text-align: right" title="Short-term investments - Cost"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;21,078,059&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98D_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_iI_pp0p0_c20210930__us-gaap--FinancialInstrumentAxis__custom--GovernmentBackedDebtSecuritiesMember_zHDhMtVpFyW1" style="border-bottom: Black 1.5pt solid; font: 10pt Times New Roman, Times, Serif; text-align: right" title="Short-term investments - Fair Value"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;21,079,470&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98C_eus-gaap--ShortTermInvestments_iI_pp0p0_c20201231__us-gaap--FinancialInstrumentAxis__custom--GovernmentBackedDebtSecuritiesMember_z54kt7d802E9" style="border-bottom: Black 1.5pt solid; font: 10pt Times New Roman, Times, Serif; text-align: right" title="Short-term investments - Cost"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0895"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_983_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_iI_pp0p0_c20201231__us-gaap--FinancialInstrumentAxis__custom--GovernmentBackedDebtSecuritiesMember_z43dcqp5k29h" style="border-bottom: Black 1.5pt solid; font: 10pt Times New Roman, Times, Serif; text-align: right" title="Short-term investments - Fair Value"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0897"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: bottom; background-color: White"&gt;
    &lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 2.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Total&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 2.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98D_eus-gaap--ShortTermInvestments_iI_pp0p0_c20210930_zCItIYAKCDS6" style="border-bottom: Black 2.5pt double; font: 10pt Times New Roman, Times, Serif; text-align: right" title="Short-term investments - Cost"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;28,862,224&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 2.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_985_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_iI_pp0p0_c20210930_zPjVplVgCeV2" style="border-bottom: Black 2.5pt double; font: 10pt Times New Roman, Times, Serif; text-align: right" title="Short-term investments - Fair Value"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;28,864,364&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 2.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_981_eus-gaap--ShortTermInvestments_iI_pp0p0_c20201231_zwdScDeyVgIc" style="border-bottom: Black 2.5pt double; font: 10pt Times New Roman, Times, Serif; text-align: right" title="Short-term investments - Cost"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0903"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 2.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98F_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_iI_pp0p0_c20201231_z5PkYsoXcaB1" style="border-bottom: Black 2.5pt double; font: 10pt Times New Roman, Times, Serif; text-align: right" title="Short-term investments - Fair Value"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0905"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; border-collapse: collapse; width: 100%"&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: bottom"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="6" style="border-bottom: Black 1.5pt solid; font: bold 10pt Times New Roman, Times, Serif; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;September
    30, 2021&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="6" style="border-bottom: Black 1.5pt solid; font: bold 10pt Times New Roman, Times, Serif; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;December
    31, 2020&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: bottom"&gt;
    &lt;td style="font: bold 10pt Times New Roman, Times, Serif; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font: bold 10pt Times New Roman, Times, Serif; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Cost&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font: bold 10pt Times New Roman, Times, Serif; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Fair
    Value&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font: bold 10pt Times New Roman, Times, Serif; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Cost&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font: bold 10pt Times New Roman, Times, Serif; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Fair
    Value&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="font: bold 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Short-term
    investment maturities&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: bold 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; text-align: right"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: bold 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; text-align: right"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: bold 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; text-align: right"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: bold 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; text-align: right"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: bottom; background-color: White"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; width: 44%"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Within
    3 months&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; width: 2%"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; width: 1%; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_983_ecustom--DebtSecuritiesAvailableforsaleMaturityAllocatedAndSingleMaturityDateRollingWithinThreeMonthsAmortizedCost_iI_pp0p0_c20210930_zS3J46fRddI5" style="font: 10pt Times New Roman, Times, Serif; width: 10%; text-align: right" title="Short-term investment maturities - Within 3 months, cost"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;11,998,304&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; width: 1%; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; width: 2%"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; width: 1%; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_987_ecustom--DebtSecuritiesAvailableforsaleMaturityAllocatedAndSingleMaturityDateRollingWithinThreeMonthsFairValue_iI_pp0p0_c20210930_z22mquKJYY0b" style="font: 10pt Times New Roman, Times, Serif; width: 10%; text-align: right" title="Short-term investment maturities - Within 3 months, fair value"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;11,999,400&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; width: 1%; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; width: 2%"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; width: 1%; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_982_ecustom--DebtSecuritiesAvailableforsaleMaturityAllocatedAndSingleMaturityDateRollingWithinThreeMonthsAmortizedCost_iI_pp0p0_c20201231_z9zmhKylkTr7" style="font: 10pt Times New Roman, Times, Serif; width: 10%; text-align: right" title="Short-term investment maturities - Within 3 months, cost"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0911"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; width: 1%; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; width: 2%"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; width: 1%; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_987_ecustom--DebtSecuritiesAvailableforsaleMaturityAllocatedAndSingleMaturityDateRollingWithinThreeMonthsFairValue_iI_pp0p0_c20201231_zGHosuu1zqvl" style="font: 10pt Times New Roman, Times, Serif; width: 10%; text-align: right" title="Short-term investment maturities - Within 3 months, fair value"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0913"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; width: 1%; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Between
    3-12 months&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98C_ecustom--DebtSecuritiesAvailableforsaleMaturityAllocatedAndSingleMaturityDateRollingBetweenThreeAndTwelveMonthsAmortizedCost_iI_pp0p0_c20210930_zpsqJ1z2Udga" style="border-bottom: Black 1.5pt solid; font: 10pt Times New Roman, Times, Serif; text-align: right" title="Short-term investment maturities - Between 3-12 months, cost"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;16,863,920&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98B_ecustom--DebtSecuritiesAvailableforsaleMaturityAllocatedAndSingleMaturityDateRollingBetweenThreeAndTwelveMonthsFairValue_iI_pp0p0_c20210930_zqbNZhL02jEf" style="border-bottom: Black 1.5pt solid; font: 10pt Times New Roman, Times, Serif; text-align: right" title="Short-term investment maturities - Between 3-12 months, fair value"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;16,864,964&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_980_eus-gaap--ShortTermInvestments_iI_pp0p0_c20201230_zCsx26sB427j" style="border-bottom: Black 1.5pt solid; font: 10pt Times New Roman, Times, Serif; text-align: right" title="Short-term investment maturities - Between 3-12 months, cost"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0919"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_988_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_iI_pp0p0_c20201231__us-gaap--FinancialInstrumentAxis__custom--GovernmentBackedDebtSecuritiesMember_z5iBqFQluvf" style="border-bottom: Black 1.5pt solid; font: 10pt Times New Roman, Times, Serif; text-align: right" title="Short-term investment maturities - Between 3-12 months, fair value"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0921"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: bottom; background-color: White"&gt;
    &lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 2.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Total&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 2.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_982_ecustom--AvailableForSaleDebtSecuritiesAmortizedCostBasisCurrent_iI_pp0p0_c20210930_zQ5Pg4fmo4w6" style="border-bottom: Black 2.5pt double; font: 10pt Times New Roman, Times, Serif; text-align: right" title="Total, cost"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;28,862,224&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 2.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_980_eus-gaap--AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDate_iI_pp0p0_c20210930_zPCf5TMFwaJj" style="border-bottom: Black 2.5pt double; font: 10pt Times New Roman, Times, Serif; text-align: right" title="Total, fair value"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;28,864,364&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 2.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_987_ecustom--AvailableForSaleDebtSecuritiesAmortizedCostBasisCurrent_iI_pp0p0_c20201231_zKdYKTCgLVIj" style="border-bottom: Black 2.5pt double; font: 10pt Times New Roman, Times, Serif; text-align: right" title="Total, cost"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0927"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 2.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_985_eus-gaap--AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDate_iI_pp0p0_c20201231_z1xCqLLROCDc" style="border-bottom: Black 2.5pt double; font: 10pt Times New Roman, Times, Serif; text-align: right" title="Total, fair value"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0929"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;

</us-gaap:DebtSecuritiesAvailableForSaleTableTextBlock>
    <us-gaap:ShortTermInvestments
      contextRef="AsOf2021-09-30_us-gaap_CommercialPaperMember"
      decimals="0"
      unitRef="USD">7784165</us-gaap:ShortTermInvestments>
    <us-gaap:AvailableForSaleSecuritiesDebtSecuritiesCurrent
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      decimals="0"
      unitRef="USD">7784894</us-gaap:AvailableForSaleSecuritiesDebtSecuritiesCurrent>
    <us-gaap:ShortTermInvestments
      contextRef="AsOf2021-09-30_custom_GovernmentBackedDebtSecuritiesMember"
      decimals="0"
      unitRef="USD">21078059</us-gaap:ShortTermInvestments>
    <us-gaap:AvailableForSaleSecuritiesDebtSecuritiesCurrent
      contextRef="AsOf2021-09-30_custom_GovernmentBackedDebtSecuritiesMember"
      decimals="0"
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    <us-gaap:ShortTermInvestments contextRef="AsOf2021-09-30" decimals="0" unitRef="USD">28862224</us-gaap:ShortTermInvestments>
    <us-gaap:AvailableForSaleSecuritiesDebtSecuritiesCurrent contextRef="AsOf2021-09-30" decimals="0" unitRef="USD">28864364</us-gaap:AvailableForSaleSecuritiesDebtSecuritiesCurrent>
    <CLSN:DebtSecuritiesAvailableforsaleMaturityAllocatedAndSingleMaturityDateRollingWithinThreeMonthsAmortizedCost contextRef="AsOf2021-09-30" decimals="0" unitRef="USD">11998304</CLSN:DebtSecuritiesAvailableforsaleMaturityAllocatedAndSingleMaturityDateRollingWithinThreeMonthsAmortizedCost>
    <CLSN:DebtSecuritiesAvailableforsaleMaturityAllocatedAndSingleMaturityDateRollingWithinThreeMonthsFairValue contextRef="AsOf2021-09-30" decimals="0" unitRef="USD">11999400</CLSN:DebtSecuritiesAvailableforsaleMaturityAllocatedAndSingleMaturityDateRollingWithinThreeMonthsFairValue>
    <CLSN:DebtSecuritiesAvailableforsaleMaturityAllocatedAndSingleMaturityDateRollingBetweenThreeAndTwelveMonthsAmortizedCost contextRef="AsOf2021-09-30" decimals="0" unitRef="USD">16863920</CLSN:DebtSecuritiesAvailableforsaleMaturityAllocatedAndSingleMaturityDateRollingBetweenThreeAndTwelveMonthsAmortizedCost>
    <CLSN:DebtSecuritiesAvailableforsaleMaturityAllocatedAndSingleMaturityDateRollingBetweenThreeAndTwelveMonthsFairValue contextRef="AsOf2021-09-30" decimals="0" unitRef="USD">16864964</CLSN:DebtSecuritiesAvailableforsaleMaturityAllocatedAndSingleMaturityDateRollingBetweenThreeAndTwelveMonthsFairValue>
    <CLSN:AvailableForSaleDebtSecuritiesAmortizedCostBasisCurrent contextRef="AsOf2021-09-30" decimals="0" unitRef="USD">28862224</CLSN:AvailableForSaleDebtSecuritiesAmortizedCostBasisCurrent>
    <us-gaap:AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDate contextRef="AsOf2021-09-30" decimals="0" unitRef="USD">28864364</us-gaap:AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDate>
    <us-gaap:ScheduleOfUnrealizedLossOnInvestmentsTableTextBlock contextRef="From2021-01-01to2021-09-30">&lt;p id="xdx_89F_eus-gaap--ScheduleOfUnrealizedLossOnInvestmentsTableTextBlock_z4H6v74WqIf2" style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;The
following table shows the Company&#x2019;s investment in debt securities available for sale gross unrealized gains (losses) and fair value
by investment category and length of time that individual securities have been in a continuous unrealized loss position at September
30, 2021 and December 31, 2020. The Company has reviewed individual securities to determine whether a decline in fair value below the
amortizable cost basis is other than temporary.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;span id="xdx_8BE_z9xo3x4iTPS5" style="display: none"&gt;Summary of Investment Securities Gross Unrealized Gains (Losses)&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"/&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; border-collapse: collapse; width: 100%"&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: bottom"&gt;
    &lt;td style="font: bold 10pt Times New Roman, Times, Serif; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="6" style="border-bottom: Black 1.5pt solid; font: bold 10pt Times New Roman, Times, Serif; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;September
    30, 2021&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="6" style="border-bottom: Black 1.5pt solid; font: bold 10pt Times New Roman, Times, Serif; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;December
    31, 2020&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: bottom"&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; font: bold 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Available
    for sale securities (all unrealized holding gains and losses are less than 12 months at date of measurement)&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font: bold 10pt Times New Roman, Times, Serif; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Fair
    Value&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font: 10pt Times New Roman, Times, Serif; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Unrealized
                                            Holding&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Gains
                                            (Losses)&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font: bold 10pt Times New Roman, Times, Serif; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Fair
    Value&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font: 10pt Times New Roman, Times, Serif; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Unrealized
                                            Holding&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Gains
                                            (Losses)&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: bottom"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="font: 10pt Times New Roman, Times, Serif; text-align: right"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="font: 10pt Times New Roman, Times, Serif; text-align: right"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="font: 10pt Times New Roman, Times, Serif; text-align: right"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="font: 10pt Times New Roman, Times, Serif; text-align: right"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; width: 44%; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Investments
    with unrealized gains&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; width: 2%"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; width: 1%; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98B_ecustom--AvailableForSaleSecuritiesUnrealizedGainsFairValue_iI_c20210930_zZFBcSNgdmJg" style="font: 10pt Times New Roman, Times, Serif; width: 10%; text-align: right" title="Investments with unrealized gains, Fair Value"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;21,029,520&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; width: 1%; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; width: 2%"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; width: 1%; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_980_ecustom--AvailableForSaleSecuritiesUnrealizedHoldingGainsLessThanTwelveMonths_iI_c20210930_zJYhdCRAaGdj" style="font: 10pt Times New Roman, Times, Serif; width: 10%; text-align: right" title="Investments with unrealized gains, Unrealized Holding Gains (Losses)"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;3,055&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; width: 1%; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; width: 2%"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; width: 1%; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98E_ecustom--AvailableForSaleSecuritiesUnrealizedGainsFairValue_iI_c20201231_z3M02uua3jil" style="font: 10pt Times New Roman, Times, Serif; width: 10%; text-align: right"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0936"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; width: 1%; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; width: 2%"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; width: 1%; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_982_ecustom--AvailableForSaleSecuritiesUnrealizedHoldingGainsLessThanTwelveMonths_iI_c20201231_zCpfoZv0DlK1" style="font: 10pt Times New Roman, Times, Serif; width: 10%; text-align: right" title="Investments with unrealized gains, Unrealized Holding Gains (Losses)"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0938"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; width: 1%; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: bottom; background-color: White"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: left; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Investments
    with unrealized losses&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_988_ecustom--AvailableForSaleSecuritiesUnrealizedLossFairValue_iI_c20210930_zO7ZcWPmC50l" style="border-bottom: Black 1.5pt solid; font: 10pt Times New Roman, Times, Serif; text-align: right" title="Investments with unrealized losses, Fair Value"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;7,834,844&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98A_ecustom--AvailableForSaleSecuritiesUnrealizedHoldingLossesLessThanTwelveMonths_iI_c20210930_zmB303ynsmW1" style="border-bottom: Black 1.5pt solid; font: 10pt Times New Roman, Times, Serif; text-align: right" title="Investments with unrealized Losses, Unrealized Holding Gains (Losses)"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;(916&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;)&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_980_ecustom--AvailableForSaleSecuritiesUnrealizedLossFairValue_iI_c20201231_zNVoVOYE8gWa" style="border-bottom: Black 1.5pt solid; font: 10pt Times New Roman, Times, Serif; text-align: right"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0943"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98D_ecustom--AvailableForSaleSecuritiesUnrealizedHoldingLossesLessThanTwelveMonths_iI_c20201231_z5YfLBoPLSs5" style="border-bottom: Black 1.5pt solid; font: 10pt Times New Roman, Times, Serif; text-align: right" title="Investments with unrealized Losses, Unrealized Holding Gains (Losses)"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0945"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 2.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Total&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 2.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_988_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_iI_c20210930_zJlh7KxBeonf" style="border-bottom: Black 2.5pt double; font: 10pt Times New Roman, Times, Serif; text-align: right" title="Investment securities, available for sale"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;28,864,364&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 2.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_981_ecustom--AvailableForSaleSecuritiesUnrealizedHoldingGainsLossesLessThanTwelveMonths_iI_c20210930_zAbpPPg8pkJ5" style="border-bottom: Black 2.5pt double; font: 10pt Times New Roman, Times, Serif; text-align: right" title="Investments with unrealized Gains (Losses), Unrealized Holding Gains (Losses)"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;2,139&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 2.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98E_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_iI_pp0p0_c20201231_zb9V7QrzJGT5" style="border-bottom: Black 2.5pt double; font: 10pt Times New Roman, Times, Serif; text-align: right"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0950"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 2.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_982_ecustom--AvailableForSaleSecuritiesUnrealizedHoldingGainsLossesLessThanTwelveMonths_iI_c20201231_zqL2gyJgazK2" style="border-bottom: Black 2.5pt double; font: 10pt Times New Roman, Times, Serif; text-align: right" title="Investments with unrealized Gains (Losses), Unrealized Holding Gains (Losses)"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0952"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;

</us-gaap:ScheduleOfUnrealizedLossOnInvestmentsTableTextBlock>
    <CLSN:AvailableForSaleSecuritiesUnrealizedGainsFairValue contextRef="AsOf2021-09-30" decimals="0" unitRef="USD">21029520</CLSN:AvailableForSaleSecuritiesUnrealizedGainsFairValue>
    <CLSN:AvailableForSaleSecuritiesUnrealizedHoldingGainsLessThanTwelveMonths contextRef="AsOf2021-09-30" decimals="0" unitRef="USD">3055</CLSN:AvailableForSaleSecuritiesUnrealizedHoldingGainsLessThanTwelveMonths>
    <CLSN:AvailableForSaleSecuritiesUnrealizedLossFairValue contextRef="AsOf2021-09-30" decimals="0" unitRef="USD">7834844</CLSN:AvailableForSaleSecuritiesUnrealizedLossFairValue>
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    <us-gaap:InvestmentIncomeTextBlock contextRef="From2021-01-01to2021-09-30">&lt;p id="xdx_897_eus-gaap--InvestmentIncomeTextBlock_zHJyvcuTyiSh" style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Investment
(loss) income, which includes net realized losses on sales of available for sale securities and investment income interest and dividends,
is summarized as follows:&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;span id="xdx_8B1_z2oGtiDs3Fcf" style="display: none"&gt;Summary of Net Realized Losses on Sales of Available for Sale Securities and Investment Income Interest and Dividends&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; border-collapse: collapse; width: 100%"&gt;
  &lt;tr style="display: none; vertical-align: bottom"&gt;
    &lt;td style="text-align: center"&gt;&#160;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" id="xdx_498_20210701__20210930_zJMMeE8DPxxi" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;2021&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&#160;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" id="xdx_49F_20200701__20200930_zo126XjGm0c9" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;2020&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td style="text-align: center"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="6" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Three Months Ended&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;September 30,&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td style="text-align: center"&gt;&#160;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;2021&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&#160;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;2020&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_401_eus-gaap--InvestmentIncomeInterestAndDividend_maIILNzUXt_zr2HIl3c5Qjl" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="width: 60%; text-align: left"&gt;Interest and dividends accrued and paid&lt;/td&gt;&lt;td style="width: 2%"&gt;&#160;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;$&lt;/td&gt;&lt;td style="width: 16%; text-align: right"&gt;6,288&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="width: 2%"&gt;&#160;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;$&lt;/td&gt;&lt;td style="width: 16%; text-align: right"&gt;2,857&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_40B_eus-gaap--DebtSecuritiesAvailableForSaleRealizedGainLoss_maIILNzUXt_zmMntfnfFmYe" style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left; padding-bottom: 1.5pt"&gt;Realized (losses) gains&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="border-bottom: Black 1.5pt solid; text-align: right"&gt;(2,736&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;)&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="border-bottom: Black 1.5pt solid; text-align: right"&gt;7,257&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_404_ecustom--InvestmentIncomeLossNonoperating_iT_pp0p0_mtIILNzUXt_zk3NkG4XHeza" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left; padding-bottom: 2.5pt"&gt;Investment income, net&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;$&lt;/td&gt;&lt;td style="border-bottom: Black 2.5pt double; text-align: right"&gt;3,552&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;$&lt;/td&gt;&lt;td style="border-bottom: Black 2.5pt double; text-align: right"&gt;10,114&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; border-collapse: collapse; width: 100%"&gt;
  &lt;tr style="display: none; vertical-align: bottom"&gt;
    &lt;td style="text-align: center"&gt;&#160;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" id="xdx_499_20210101__20210930_zODAjUd2SR5d" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;2021&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&#160;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" id="xdx_490_20200101__20200930_z2qBoVdTjcP5" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;2020&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
&lt;tr style="vertical-align: bottom"&gt;
    &lt;td style="text-align: center"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="6" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Nine Months Ended&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;September 30,&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td style="text-align: center"&gt;&#160;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;2021&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&#160;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;2020&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_40E_eus-gaap--InvestmentIncomeInterestAndDividend_maIILNz6Ly_zB02x4Ro85if" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="width: 60%; text-align: left"&gt;Interest and dividends accrued and paid&lt;/td&gt;&lt;td style="width: 2%"&gt;&#160;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;$&lt;/td&gt;&lt;td style="width: 16%; text-align: right"&gt;10,135&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="width: 2%"&gt;&#160;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;$&lt;/td&gt;&lt;td style="width: 16%; text-align: right"&gt;66,029&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_407_eus-gaap--DebtSecuritiesAvailableForSaleRealizedGainLoss_maIILNz6Ly_zGinddnHyn86" style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left; padding-bottom: 1.5pt"&gt;Realized (losses) gains&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="border-bottom: Black 1.5pt solid; text-align: right"&gt;(4,521&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;)&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="border-bottom: Black 1.5pt solid; text-align: right"&gt;53,354&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_402_ecustom--InvestmentIncomeLossNonoperating_iT_pp0p0_mtIILNz6Ly_zlwaaEvIZ3Ag" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left; padding-bottom: 2.5pt"&gt;Investment income, net&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;$&lt;/td&gt;&lt;td style="border-bottom: Black 2.5pt double; text-align: right"&gt;5,614&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;$&lt;/td&gt;&lt;td style="border-bottom: Black 2.5pt double; text-align: right"&gt;119,383&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;

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      contextRef="From2020-07-012020-09-30"
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      contextRef="From2021-07-012021-09-30"
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      contextRef="From2020-01-012020-09-30"
      decimals="0"
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      decimals="0"
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      contextRef="From2020-01-012020-09-30"
      decimals="0"
      unitRef="USD">119383</CLSN:InvestmentIncomeLossNonoperating>
    <us-gaap:DerivativesAndFairValueTextBlock contextRef="From2021-01-01to2021-09-30">&lt;p id="xdx_803_eus-gaap--DerivativesAndFairValueTextBlock_zq9omfniWwO4" style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Note
8. &lt;span id="xdx_82D_zbCKoWsAP8W7"&gt;Fair Value Measurements&lt;/span&gt;&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;FASB
ASC Section 820, &lt;i&gt;Fair Value Measurements and Disclosures&lt;/i&gt; establishes a three-level hierarchy for fair value measurements which
requires an entity to maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value. The
three levels of inputs that may be used to measure fair value are as follows:&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-left: 0.5in; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Level
1: Quoted prices (unadjusted) or identical assets or liabilities in active markets that the entity has the ability to access as of the
measurement date;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-left: 0.5in; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-left: 0.5in; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"/&gt;&lt;/p&gt;



&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-left: 0.5in; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-left: 0.5in; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Level
2: Significant other observable inputs other than Level 1 prices such as quoted prices for similar assets or liabilities; quoted prices
in markets that are not active; or other inputs that are observable or can be corroborated by observable market data; and&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-left: 0.5in; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-left: 0.5in; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Level
3: Significant unobservable inputs that reflect a reporting entity&#x2019;s own assumptions that market participants would use in pricing
an asset or liability.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Cash
and cash equivalents, other current assets, accounts payable and other accrued liabilities are reflected in the condensed consolidated
balance sheet at their approximate estimated fair values primarily due to their short-term nature. The fair values of securities available
for sale is determined by relying on the securities&#x2019; relationship to other benchmark quoted securities and classified its investments
as Level 2 items in both 2021 and 2020. There were no transfers of assets or liabilities between Level 1 and Level 2 and no transfers
in or out of Level 3 during the nine-months ended September 30, 2021 or during the year ended December 31, 2020. The changes in Level
3 liabilities were the result of changes in the fair value of the earn-out milestone liability included in earnings and in-process R&amp;amp;D.
The earnout milestone liability is valued using a risk-adjusted assessment of the probability of payment of each milestone, discounted
to present value using an estimated time to achieve the milestone (see Note 14).&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p id="xdx_89A_eus-gaap--ScheduleOfFairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisTableTextBlock_zSTszVAOUxV2" style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Assets
and liabilities measured at fair value are summarized below:&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;span id="xdx_8B7_zjYK1kPaGMNa" style="display: none"&gt;Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; border-collapse: collapse; width: 100%"&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td style="text-align: center"&gt;&#160;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;Total Fair Value&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&#160;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1)&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Significant Other Observable Inputs&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;(Level 2)&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Significant Unobservable Inputs&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;(Level 3)&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td&gt;Assets:&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td&gt;Recurring items as of September 30, 2021&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="padding-left: 10pt; width: 44%; text-align: left"&gt;Investment in debt securities - available for sale, at fair value&lt;/td&gt;&lt;td style="width: 2%"&gt;&#160;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_98C_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_iI_pp0p0_c20210930__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsRecurringMember__us-gaap--FinancialInstrumentAxis__us-gaap--CorporateDebtSecuritiesMember_zXZzxfcgu2Gf" style="width: 10%; text-align: right" title="Investment securities, available for sale"&gt;28,864,364&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="width: 2%"&gt;&#160;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_98C_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_iI_pp0p0_c20210930__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsRecurringMember__us-gaap--FairValueByFairValueHierarchyLevelAxis__us-gaap--FairValueInputsLevel1Member__us-gaap--FinancialInstrumentAxis__us-gaap--CorporateDebtSecuritiesMember_zy0hWtXithp3" style="width: 10%; text-align: right" title="Investment securities, available for sale"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0980"&gt;&#x2013;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="width: 2%"&gt;&#160;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_98B_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_iI_pp0p0_c20210930__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsRecurringMember__us-gaap--FairValueByFairValueHierarchyLevelAxis__us-gaap--FairValueInputsLevel2Member__us-gaap--FinancialInstrumentAxis__us-gaap--CorporateDebtSecuritiesMember_z3hEqnqacG28" style="width: 10%; text-align: right" title="Investment securities, available for sale"&gt;28,864,364&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="width: 2%"&gt;&#160;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_98F_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_iI_pp0p0_c20210930__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsRecurringMember__us-gaap--FairValueByFairValueHierarchyLevelAxis__us-gaap--FairValueInputsLevel3Member__us-gaap--FinancialInstrumentAxis__us-gaap--CorporateDebtSecuritiesMember_z7p8nuMF299c" style="width: 10%; text-align: right" title="Investment securities, available for sale"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0984"&gt;&#x2013;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td&gt;Non-recurring items as of September 30, 2021&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="padding-left: 10pt; text-align: left"&gt;In-process R&amp;amp;D (Note 9)&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_981_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_iI_pp0p0_c20210930__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsNonrecurringMember__us-gaap--FinancialInstrumentAxis__custom--InprocessRandDMember_z8UW5WRWxIGk" style="text-align: right" title="Investment securities, available for sale"&gt;13,366,234&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_984_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_iI_pp0p0_c20210930__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsNonrecurringMember__us-gaap--FairValueByFairValueHierarchyLevelAxis__us-gaap--FairValueInputsLevel1Member__us-gaap--FinancialInstrumentAxis__custom--InprocessRandDMember_zG9xFn7DSJi7" style="text-align: right" title="Investment securities, available for sale"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0988"&gt;&#x2013;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_981_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_iI_pp0p0_c20210930__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsNonrecurringMember__us-gaap--FairValueByFairValueHierarchyLevelAxis__us-gaap--FairValueInputsLevel2Member__us-gaap--FinancialInstrumentAxis__custom--InprocessRandDMember_zlruH49MOaJi" style="text-align: right" title="Investment securities, available for sale"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0990"&gt;&#x2013;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_98C_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_iI_pp0p0_c20210930__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsNonrecurringMember__us-gaap--FairValueByFairValueHierarchyLevelAxis__us-gaap--FairValueInputsLevel3Member__us-gaap--FinancialInstrumentAxis__custom--InprocessRandDMember_zWF0SjlaALmc" style="text-align: right" title="Investment securities, available for sale"&gt;13,366,234&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td&gt;Non-recurring items as of December 31, 2020&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="padding-left: 10pt; text-align: left"&gt;In-process R&amp;amp;D (Note 9)&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_989_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_iI_pp0p0_c20201231__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsNonrecurringMember__us-gaap--FinancialInstrumentAxis__custom--InprocessRandDMember_zibGCAhcwgk9" style="text-align: right" title="Investment securities, available for sale"&gt;13,366,234&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_985_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_iI_pp0p0_c20201231__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsNonrecurringMember__us-gaap--FairValueByFairValueHierarchyLevelAxis__us-gaap--FairValueInputsLevel1Member__us-gaap--FinancialInstrumentAxis__custom--InprocessRandDMember_zENd03hUyUkd" style="text-align: right" title="Investment securities, available for sale"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0996"&gt;&#x2013;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_982_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_iI_pp0p0_c20201231__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsNonrecurringMember__us-gaap--FairValueByFairValueHierarchyLevelAxis__us-gaap--FairValueInputsLevel2Member__us-gaap--FinancialInstrumentAxis__custom--InprocessRandDMember_zIzZshSe4EGb" style="text-align: right" title="Investment securities, available for sale"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0998"&gt;&#x2013;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_987_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_iI_pp0p0_c20201231__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsNonrecurringMember__us-gaap--FairValueByFairValueHierarchyLevelAxis__us-gaap--FairValueInputsLevel3Member__us-gaap--FinancialInstrumentAxis__custom--InprocessRandDMember_zdsIyRizNdIc" style="text-align: right" title="Investment securities, available for sale"&gt;13,366,234&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td&gt;Liabilities:&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td&gt;Recurring items as of September 30, 2021&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="padding-left: 10pt; text-align: left"&gt;Earn-out milestone liability (Note 14)&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_984_eus-gaap--BusinessCombinationContingentConsiderationLiabilityNoncurrent_iI_pp0p0_c20210930__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsRecurringMember_zhNvCEjvNobg" style="text-align: right" title="Earn-out milestone liability"&gt;7,345,000&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_986_eus-gaap--BusinessCombinationContingentConsiderationLiabilityNoncurrent_iI_pp0p0_c20210930__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsRecurringMember__us-gaap--FairValueByFairValueHierarchyLevelAxis__us-gaap--FairValueInputsLevel1Member_zfsRzqpUcAMh" style="text-align: right" title="Earn-out milestone liability"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl1004"&gt;&#x2013;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_98F_eus-gaap--BusinessCombinationContingentConsiderationLiabilityNoncurrent_iI_pp0p0_c20210930__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsRecurringMember__us-gaap--FairValueByFairValueHierarchyLevelAxis__us-gaap--FairValueInputsLevel2Member_zAitZKwTioF4" style="text-align: right" title="Earn-out milestone liability"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl1006"&gt;&#x2013;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_987_eus-gaap--BusinessCombinationContingentConsiderationLiabilityNoncurrent_iI_pp0p0_c20210930__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsRecurringMember__us-gaap--FairValueByFairValueHierarchyLevelAxis__us-gaap--FairValueInputsLevel3Member_z2IMOcFbZ9M2" style="text-align: right" title="Earn-out milestone liability"&gt;7,345,000&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td&gt;Recurring items as of December 31, 2020&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="padding-left: 10pt; text-align: left"&gt;Earn-out milestone liability (Note 14)&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_982_eus-gaap--BusinessCombinationContingentConsiderationLiabilityNoncurrent_iI_pp0p0_c20201231__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsRecurringMember_zAxwAKDQbk7k" style="text-align: right" title="Earn-out milestone liability"&gt;7,018,000&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_98A_eus-gaap--BusinessCombinationContingentConsiderationLiabilityNoncurrent_iI_pp0p0_c20201231__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsRecurringMember__us-gaap--FairValueByFairValueHierarchyLevelAxis__us-gaap--FairValueInputsLevel1Member_zIaho4WjgdJf" style="text-align: right" title="Earn-out milestone liability"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl1012"&gt;&#x2013;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_98A_eus-gaap--BusinessCombinationContingentConsiderationLiabilityNoncurrent_iI_pp0p0_c20201231__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsRecurringMember__us-gaap--FairValueByFairValueHierarchyLevelAxis__us-gaap--FairValueInputsLevel2Member_zjdLAtno3aMc" style="text-align: right" title="Earn-out milestone liability"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl1014"&gt;&#x2013;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_98E_eus-gaap--BusinessCombinationContingentConsiderationLiabilityNoncurrent_iI_pp0p0_c20201231__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsRecurringMember__us-gaap--FairValueByFairValueHierarchyLevelAxis__us-gaap--FairValueInputsLevel3Member_z8jF3BtxZxK4" style="text-align: right" title="Earn-out milestone liability"&gt;7,018,000&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;

&lt;p id="xdx_8AE_z8Lt5k8fbgHa" style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

</us-gaap:DerivativesAndFairValueTextBlock>
    <us-gaap:ScheduleOfFairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisTableTextBlock contextRef="From2021-01-01to2021-09-30">&lt;p id="xdx_89A_eus-gaap--ScheduleOfFairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisTableTextBlock_zSTszVAOUxV2" style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Assets
and liabilities measured at fair value are summarized below:&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;span id="xdx_8B7_zjYK1kPaGMNa" style="display: none"&gt;Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; border-collapse: collapse; width: 100%"&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td style="text-align: center"&gt;&#160;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;Total Fair Value&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&#160;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1)&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Significant Other Observable Inputs&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;(Level 2)&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Significant Unobservable Inputs&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;(Level 3)&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td&gt;Assets:&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td&gt;Recurring items as of September 30, 2021&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="padding-left: 10pt; width: 44%; text-align: left"&gt;Investment in debt securities - available for sale, at fair value&lt;/td&gt;&lt;td style="width: 2%"&gt;&#160;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_98C_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_iI_pp0p0_c20210930__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsRecurringMember__us-gaap--FinancialInstrumentAxis__us-gaap--CorporateDebtSecuritiesMember_zXZzxfcgu2Gf" style="width: 10%; text-align: right" title="Investment securities, available for sale"&gt;28,864,364&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="width: 2%"&gt;&#160;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_98C_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_iI_pp0p0_c20210930__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsRecurringMember__us-gaap--FairValueByFairValueHierarchyLevelAxis__us-gaap--FairValueInputsLevel1Member__us-gaap--FinancialInstrumentAxis__us-gaap--CorporateDebtSecuritiesMember_zy0hWtXithp3" style="width: 10%; text-align: right" title="Investment securities, available for sale"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0980"&gt;&#x2013;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="width: 2%"&gt;&#160;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_98B_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_iI_pp0p0_c20210930__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsRecurringMember__us-gaap--FairValueByFairValueHierarchyLevelAxis__us-gaap--FairValueInputsLevel2Member__us-gaap--FinancialInstrumentAxis__us-gaap--CorporateDebtSecuritiesMember_z3hEqnqacG28" style="width: 10%; text-align: right" title="Investment securities, available for sale"&gt;28,864,364&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="width: 2%"&gt;&#160;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_98F_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_iI_pp0p0_c20210930__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsRecurringMember__us-gaap--FairValueByFairValueHierarchyLevelAxis__us-gaap--FairValueInputsLevel3Member__us-gaap--FinancialInstrumentAxis__us-gaap--CorporateDebtSecuritiesMember_z7p8nuMF299c" style="width: 10%; text-align: right" title="Investment securities, available for sale"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0984"&gt;&#x2013;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td&gt;Non-recurring items as of September 30, 2021&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="padding-left: 10pt; text-align: left"&gt;In-process R&amp;amp;D (Note 9)&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_981_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_iI_pp0p0_c20210930__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsNonrecurringMember__us-gaap--FinancialInstrumentAxis__custom--InprocessRandDMember_z8UW5WRWxIGk" style="text-align: right" title="Investment securities, available for sale"&gt;13,366,234&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_984_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_iI_pp0p0_c20210930__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsNonrecurringMember__us-gaap--FairValueByFairValueHierarchyLevelAxis__us-gaap--FairValueInputsLevel1Member__us-gaap--FinancialInstrumentAxis__custom--InprocessRandDMember_zG9xFn7DSJi7" style="text-align: right" title="Investment securities, available for sale"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0988"&gt;&#x2013;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_981_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_iI_pp0p0_c20210930__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsNonrecurringMember__us-gaap--FairValueByFairValueHierarchyLevelAxis__us-gaap--FairValueInputsLevel2Member__us-gaap--FinancialInstrumentAxis__custom--InprocessRandDMember_zlruH49MOaJi" style="text-align: right" title="Investment securities, available for sale"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0990"&gt;&#x2013;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_98C_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_iI_pp0p0_c20210930__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsNonrecurringMember__us-gaap--FairValueByFairValueHierarchyLevelAxis__us-gaap--FairValueInputsLevel3Member__us-gaap--FinancialInstrumentAxis__custom--InprocessRandDMember_zWF0SjlaALmc" style="text-align: right" title="Investment securities, available for sale"&gt;13,366,234&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td&gt;Non-recurring items as of December 31, 2020&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="padding-left: 10pt; text-align: left"&gt;In-process R&amp;amp;D (Note 9)&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_989_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_iI_pp0p0_c20201231__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsNonrecurringMember__us-gaap--FinancialInstrumentAxis__custom--InprocessRandDMember_zibGCAhcwgk9" style="text-align: right" title="Investment securities, available for sale"&gt;13,366,234&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_985_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_iI_pp0p0_c20201231__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsNonrecurringMember__us-gaap--FairValueByFairValueHierarchyLevelAxis__us-gaap--FairValueInputsLevel1Member__us-gaap--FinancialInstrumentAxis__custom--InprocessRandDMember_zENd03hUyUkd" style="text-align: right" title="Investment securities, available for sale"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0996"&gt;&#x2013;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_982_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_iI_pp0p0_c20201231__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsNonrecurringMember__us-gaap--FairValueByFairValueHierarchyLevelAxis__us-gaap--FairValueInputsLevel2Member__us-gaap--FinancialInstrumentAxis__custom--InprocessRandDMember_zIzZshSe4EGb" style="text-align: right" title="Investment securities, available for sale"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0998"&gt;&#x2013;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_987_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_iI_pp0p0_c20201231__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsNonrecurringMember__us-gaap--FairValueByFairValueHierarchyLevelAxis__us-gaap--FairValueInputsLevel3Member__us-gaap--FinancialInstrumentAxis__custom--InprocessRandDMember_zdsIyRizNdIc" style="text-align: right" title="Investment securities, available for sale"&gt;13,366,234&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td&gt;Liabilities:&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td&gt;Recurring items as of September 30, 2021&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="padding-left: 10pt; text-align: left"&gt;Earn-out milestone liability (Note 14)&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_984_eus-gaap--BusinessCombinationContingentConsiderationLiabilityNoncurrent_iI_pp0p0_c20210930__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsRecurringMember_zhNvCEjvNobg" style="text-align: right" title="Earn-out milestone liability"&gt;7,345,000&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_986_eus-gaap--BusinessCombinationContingentConsiderationLiabilityNoncurrent_iI_pp0p0_c20210930__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsRecurringMember__us-gaap--FairValueByFairValueHierarchyLevelAxis__us-gaap--FairValueInputsLevel1Member_zfsRzqpUcAMh" style="text-align: right" title="Earn-out milestone liability"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl1004"&gt;&#x2013;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_98F_eus-gaap--BusinessCombinationContingentConsiderationLiabilityNoncurrent_iI_pp0p0_c20210930__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsRecurringMember__us-gaap--FairValueByFairValueHierarchyLevelAxis__us-gaap--FairValueInputsLevel2Member_zAitZKwTioF4" style="text-align: right" title="Earn-out milestone liability"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl1006"&gt;&#x2013;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_987_eus-gaap--BusinessCombinationContingentConsiderationLiabilityNoncurrent_iI_pp0p0_c20210930__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsRecurringMember__us-gaap--FairValueByFairValueHierarchyLevelAxis__us-gaap--FairValueInputsLevel3Member_z2IMOcFbZ9M2" style="text-align: right" title="Earn-out milestone liability"&gt;7,345,000&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td&gt;Recurring items as of December 31, 2020&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="padding-left: 10pt; text-align: left"&gt;Earn-out milestone liability (Note 14)&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_982_eus-gaap--BusinessCombinationContingentConsiderationLiabilityNoncurrent_iI_pp0p0_c20201231__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsRecurringMember_zAxwAKDQbk7k" style="text-align: right" title="Earn-out milestone liability"&gt;7,018,000&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_98A_eus-gaap--BusinessCombinationContingentConsiderationLiabilityNoncurrent_iI_pp0p0_c20201231__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsRecurringMember__us-gaap--FairValueByFairValueHierarchyLevelAxis__us-gaap--FairValueInputsLevel1Member_zIaho4WjgdJf" style="text-align: right" title="Earn-out milestone liability"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl1012"&gt;&#x2013;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_98A_eus-gaap--BusinessCombinationContingentConsiderationLiabilityNoncurrent_iI_pp0p0_c20201231__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsRecurringMember__us-gaap--FairValueByFairValueHierarchyLevelAxis__us-gaap--FairValueInputsLevel2Member_zjdLAtno3aMc" style="text-align: right" title="Earn-out milestone liability"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl1014"&gt;&#x2013;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_98E_eus-gaap--BusinessCombinationContingentConsiderationLiabilityNoncurrent_iI_pp0p0_c20201231__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsRecurringMember__us-gaap--FairValueByFairValueHierarchyLevelAxis__us-gaap--FairValueInputsLevel3Member_z8jF3BtxZxK4" style="text-align: right" title="Earn-out milestone liability"&gt;7,018,000&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;

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    <us-gaap:IntangibleAssetsDisclosureTextBlock contextRef="From2021-01-01to2021-09-30">&lt;p id="xdx_80E_eus-gaap--IntangibleAssetsDisclosureTextBlock_zG5c6tNMLUUe" style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Note
9. &lt;span id="xdx_824_zFdIK6I0cIEg"&gt;Intangible Assets&lt;/span&gt;&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;In
June 2014, we completed the acquisition of substantially all of the assets of EGEN, Inc., an Alabama corporation, which has changed its
company name to EGWU, Inc. after the closing of the acquisition (&#x201c;EGEN&#x201d;). We acquired all of EGEN&#x2019;s right, title and
interest in and to substantially all of the assets of EGEN, including cash and cash equivalents, patents, trademarks and other intellectual
property rights, clinical data, certain contracts, licenses and permits, equipment, furniture, office equipment, furnishings, supplies
and other tangible personal property. In addition, CLSN Laboratories assumed certain specified liabilities of EGEN, including the liabilities
arising out of the acquired contracts and other assets relating to periods after the closing date.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;i&gt;Acquired
In-process Research and Development&lt;/i&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Acquired
in-process research and development (IPR&amp;amp;D) consists of EGEN&#x2019;s drug technology platforms: TheraPlas and TheraSilence. The fair
value of the IPR&amp;amp;D drug technology platforms was estimated to be $&lt;span id="xdx_907_eus-gaap--IndefinitelivedIntangibleAssetsAcquired_c20210101__20210930__us-gaap--BusinessAcquisitionAxis__custom--EGENIncMember__dei--LegalEntityAxis__custom--IPRAndDDrugTechnologyPlatformsMember_pn5n6" title="Indefinite-lived Intangible Assets Acquired"&gt;24.2&lt;/span&gt; million as of the acquisition date. As of the closing of the
acquisition, the IPR&amp;amp;D was considered indefinite lived intangible assets and will not be amortized. IPR&amp;amp;D is reviewed for impairment
at least annually as of our third quarter ended September 30, and whenever events or changes in circumstances indicate that the carrying
value of the assets might not be recoverable. The Company&#x2019;s IPR&amp;amp;D consisted of three core elements, its RNA delivery system,
its glioblastoma multiforme cancer (GBM) product candidate and its ovarian cancer indication.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;



&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"/&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;The
Company&#x2019;s ovarian cancer indication, with original value of $&lt;span id="xdx_909_eus-gaap--FinitelivedIntangibleAssetsAcquired1_c20210101__20210930__dei--LegalEntityAxis__custom--IPRAndDDrugTechnologyPlatformsMember__us-gaap--ContingentConsiderationByTypeAxis__custom--OvarianCancerMember_pn5n6" title="Finite-lived Intangible Assets Acquired"&gt;13.3&lt;/span&gt; million, has not been impaired since its acquisition. At September
30, 2021, the Company evaluated its IPR&amp;amp;D of the ovarian cancer indication and concluded that it is not more likely than not that
the asset is impaired. As no other indicators of impairment existed during the fourth quarter of 2020 or first nine months of 2021, &lt;span id="xdx_90C_eus-gaap--AssetImpairmentCharges_pp0p0_do_c20210101__20210930__dei--LegalEntityAxis__custom--IPRAndDDrugTechnologyPlatformsMember_zCSjt3sk8NC2" title="Asset Impairment Charges"&gt;&lt;span id="xdx_905_eus-gaap--AssetImpairmentCharges_pp0p0_do_c20200101__20200930__dei--LegalEntityAxis__custom--IPRAndDDrugTechnologyPlatformsMember_zO0GUJnMXXtj" title="Asset Impairment Charges"&gt;&lt;span id="xdx_90F_eus-gaap--AssetImpairmentCharges_pp0p0_do_c20210701__20210930__dei--LegalEntityAxis__custom--IPRAndDDrugTechnologyPlatformsMember_z7uAEcynMYF1" title="Asset Impairment Charges"&gt;&lt;span id="xdx_906_eus-gaap--AssetImpairmentCharges_pp0p0_do_c20200701__20200930__dei--LegalEntityAxis__custom--IPRAndDDrugTechnologyPlatformsMember_zDk3IHOMTIr2" title="Asset Impairment Charges"&gt;no&lt;/span&gt;&lt;/span&gt;&lt;/span&gt;&lt;/span&gt;
impairment charges were recorded during the three or nine-months ended September 30, 2021 and 2020.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;The
Company&#x2019;s GBM candidate, with original value of $&lt;span id="xdx_90D_eus-gaap--AssetImpairmentCharges_c20180101__20181231__us-gaap--BusinessAcquisitionAxis__custom--EGENIncMember__us-gaap--ContingentConsiderationByTypeAxis__custom--GlioblastomaMultiformeBrainCancerMember_pn5n6" title="Asset Impairment Charges"&gt;9.4&lt;/span&gt; million, had cumulative impairments through 2018 of $&lt;span id="xdx_90C_eus-gaap--AssetImpairmentCharges_c20180101__20181231__us-gaap--BusinessAcquisitionAxis__custom--EGENIncMember_pn6n6" title="Asset Impairment Charges"&gt;7&lt;/span&gt; million, with remaining
carrying value of $&lt;span id="xdx_904_eus-gaap--AssetImpairmentCharges_c20190101__20191231__us-gaap--ContingentConsiderationByTypeAxis__custom--GlioblastomaMultiformeBrainCancerMember_pn5n6" title="Asset Impairment Charges"&gt;2.4&lt;/span&gt; million at December 31, 2019. On September 30, 2020, the Company evaluated its IPR&amp;amp;D for the (GBM) product
candidate and concluded that it is more likely than not that the asset is further impaired. After this assessment on September 30, 2020,
the Company wrote off the remaining $&lt;span id="xdx_905_eus-gaap--AssetImpairmentCharges_c20200929__20200930__us-gaap--BusinessAcquisitionAxis__custom--EGENIncMember__us-gaap--ContingentConsiderationByTypeAxis__custom--GlioblastomaMultiformeBrainCancerMember_pn5n6" title="Asset Impairment Charges"&gt;2.4&lt;/span&gt; million of this asset, thereby recognizing a non-cash charge of $&lt;span id="xdx_905_ecustom--NoncashCharge_c20200701__20200930__us-gaap--BusinessAcquisitionAxis__custom--EGENIncMember__us-gaap--ContingentConsiderationByTypeAxis__custom--GlioblastomaMultiformeBrainCancerMember_pn5n6" title="Noncash Charge"&gt;2.4&lt;/span&gt; million in the third quarter
of 2020.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;i&gt;Covenants
Not to Compete&lt;/i&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Pursuant
to the EGEN Purchase Agreement, EGEN provided certain covenants (&#x201c;Covenant Not To Compete&#x201d;) to the Company whereby EGEN agreed,
during the period ending on the seventh anniversary of the closing date of the acquisition on June 20, 2014, not to enter into any business,
directly or indirectly, which competes with the business of the Company, nor will it contact, solicit or approach any of the employees
of the Company for purposes of offering employment. The Covenant Not to Compete which was valued at approximately $&lt;span id="xdx_90F_eus-gaap--FinitelivedIntangibleAssetsAcquired1_c20210101__20210930__us-gaap--BusinessAcquisitionAxis__custom--EGENIncMember__us-gaap--TypeOfArrangementAxis__custom--PurchaseAgreementMember_pn5n6" title="Finite-lived Intangible Assets Acquired"&gt;1.6&lt;/span&gt; million at the
date of the EGEN acquisition has a definitive life and is amortized on a straight-line basis over its life of &lt;span id="xdx_90A_eus-gaap--FiniteLivedIntangibleAssetUsefulLife_dt_c20210101__20210930__us-gaap--BusinessAcquisitionAxis__custom--EGENIncMember__us-gaap--TypeOfArrangementAxis__custom--PurchaseAgreementMember_zHWuRCnsvhu7" title="Finite-Lived Intangible Asset, Useful Life"&gt;7 years&lt;/span&gt;. The Company recognized
the remaining carrying value of $&lt;span id="xdx_90A_eus-gaap--AdjustmentForAmortization_pp0p0_c20210101__20210630__us-gaap--BusinessAcquisitionAxis__custom--EGENIncMember__us-gaap--TypeOfArrangementAxis__custom--PurchaseAgreementMember_zHj3gbFn4V82" title="Amortization expenses"&gt;113,660&lt;/span&gt; as amortization expense in the first half of 2021. The carrying value of the Covenant Not to
Compete was fully amortized as of June 30, 2021 and had a carrying value of $&lt;span id="xdx_908_eus-gaap--FiniteLivedIntangibleAssetsNet_iI_pp0p0_c20201231__us-gaap--TypeOfArrangementAxis__custom--AspirePurchaseAgreementsMember_zCHaw2gbSIEb" title="Finite-Lived Intangible Assets, Net"&gt;113,660&lt;/span&gt;, net of $&lt;span id="xdx_904_eus-gaap--FiniteLivedIntangibleAssetsAccumulatedAmortization_iI_pp0p0_c20201231__us-gaap--TypeOfArrangementAxis__custom--AspirePurchaseAgreementsMember_z4RJKdTD1oqi" title="Finite-Lived Intangible Assets, Accumulated Amortization"&gt;1,477,554&lt;/span&gt; accumulated amortization, as
of December 31, 2020. The Company recognized amortization expense of $&lt;span id="xdx_90A_eus-gaap--AdjustmentForAmortization_pp0p0_c20200701__20200930__us-gaap--BusinessAcquisitionAxis__custom--EGENIncMember__us-gaap--TypeOfArrangementAxis__custom--PurchaseAgreementMember_z5UtUTnMaFpj" title="Amortization"&gt;56,830&lt;/span&gt; and &lt;span id="xdx_90B_eus-gaap--AdjustmentForAmortization_pp0p0_c20200101__20200930__us-gaap--BusinessAcquisitionAxis__custom--EGENIncMember__us-gaap--TypeOfArrangementAxis__custom--PurchaseAgreementMember_zgnkO0ahkyYa"&gt;170,487&lt;/span&gt; in the three-month and nine-month periods ended
September 30, 2020.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;i&gt;Goodwill&lt;/i&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;The
purchase price exceeded the estimated fair value of the net assets acquired by approximately $&lt;span id="xdx_900_eus-gaap--GoodwillAcquiredDuringPeriod_c20210101__20210930__us-gaap--BusinessAcquisitionAxis__custom--EGENIncMember_pn5n6" title="Goodwill, Acquired During Period"&gt;2.0&lt;/span&gt; million which was recorded as Goodwill.
Goodwill represents the difference between the total purchase price for the net assets purchased from EGEN and the aggregate fair values
of tangible and intangible assets acquired, less liabilities assumed. Goodwill is reviewed for impairment at least annually as of our
third quarter ended September 30 or sooner if we believe indicators of impairment exist. As of September 30, 2021, we concluded that
the Company&#x2019;s fair value exceeded its carrying value therefore &#x201c;it is not more likely than not&#x201d; that the Goodwill was
impaired.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p id="xdx_898_eus-gaap--FiniteLivedAndIndefiniteLivedIntangibleAssetsAcquiredAsPartOfBusinessCombinationTableTextBlock_zXDuovtJEQXe" style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Following
is a summary of the net fair value of the assets acquired in the EGEN asset acquisition for the nine-month period ended September 30,
2021:&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;span id="xdx_8B0_z0EHPjzNCcKb" style="display: none"&gt;Schedule of Fair Value of Assets Acquired&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; border-collapse: collapse; width: 100%"&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td style="text-align: center"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;IPR&amp;amp;D&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;Goodwill&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;Covenant Not To Compete&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="font-weight: bold"&gt;For the nine-months ended September 30, 2021&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="width: 55%; text-align: left"&gt;Balance at January 1, 2021, net&lt;/td&gt;&lt;td style="width: 2%"&gt;&#160;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_98E_eus-gaap--FiniteLivedIntangibleAssetsNet_iS_pp0p0_c20210101__20210930__us-gaap--FairValueByAssetClassAxis__custom--IPRAndDMember_zq7Dgx9SsUVc" style="width: 11%; text-align: right" title="Intangible assets, beginning balance"&gt;13,366,234&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="width: 2%"&gt;&#160;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_98B_eus-gaap--FiniteLivedIntangibleAssetsNet_iS_pp0p0_c20210101__20210930__us-gaap--FairValueByAssetClassAxis__us-gaap--GoodwillMember_z0J0mdcEYax9" style="width: 11%; text-align: right" title="Intangible assets, beginning balance"&gt;1,976,101&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="width: 2%"&gt;&#160;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_983_eus-gaap--FiniteLivedIntangibleAssetsNet_iS_pp0p0_c20210101__20210930__us-gaap--FiniteLivedIntangibleAssetsByMajorClassAxis__us-gaap--NoncompeteAgreementsMember_zpqj3DmNvL4l" style="width: 11%; text-align: right" title="Intangible assets, beginning balance"&gt;113,660&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="padding-bottom: 1.5pt"&gt;Amortization&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_98F_eus-gaap--AmortizationOfIntangibleAssets_c20210101__20210930__us-gaap--FairValueByAssetClassAxis__custom--IPRAndDMember_pp0p0" style="border-bottom: Black 1.5pt solid; text-align: right" title="Amortization"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl1065"&gt;-&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_984_eus-gaap--AmortizationOfIntangibleAssets_c20210101__20210930__us-gaap--FairValueByAssetClassAxis__us-gaap--GoodwillMember_pp0p0" style="border-bottom: Black 1.5pt solid; text-align: right" title="Amortization"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl1067"&gt;-&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_98F_eus-gaap--AmortizationOfIntangibleAssets_c20210101__20210930__us-gaap--FiniteLivedIntangibleAssetsByMajorClassAxis__us-gaap--NoncompeteAgreementsMember_pp0p0" style="border-bottom: Black 1.5pt solid; text-align: right" title="Amortization"&gt;(113,660&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;)&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left; padding-bottom: 2.5pt"&gt;Balance at September 30, 2021, net&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_984_eus-gaap--FiniteLivedIntangibleAssetsNet_iE_pp0p0_c20210101__20210930__us-gaap--FairValueByAssetClassAxis__custom--IPRAndDMember_zFup0rr4aQHa" style="border-bottom: Black 2.5pt double; text-align: right" title="Intangible assets, ending balance"&gt;13,366,234&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_98A_eus-gaap--FiniteLivedIntangibleAssetsNet_iE_pp0p0_c20210101__20210930__us-gaap--FairValueByAssetClassAxis__us-gaap--GoodwillMember_z8vEWj0X076d" style="border-bottom: Black 2.5pt double; text-align: right" title="Intangible assets, ending balance"&gt;1,976,101&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_98D_eus-gaap--FiniteLivedIntangibleAssetsNet_iE_pp0p0_c20210101__20210930__us-gaap--FiniteLivedIntangibleAssetsByMajorClassAxis__us-gaap--NoncompeteAgreementsMember_zSULCWREzVBl" style="border-bottom: Black 2.5pt double; text-align: right" title="Intangible assets, ending balance"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl1075"&gt;-&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;

&lt;p id="xdx_8A3_zdeGUTSHSZ07" style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

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      contextRef="AsOf2020-12-31_custom_AspirePurchaseAgreementsMember"
      decimals="0"
      unitRef="USD">113660</us-gaap:FiniteLivedIntangibleAssetsNet>
    <us-gaap:FiniteLivedIntangibleAssetsAccumulatedAmortization
      contextRef="AsOf2020-12-31_custom_AspirePurchaseAgreementsMember"
      decimals="0"
      unitRef="USD">1477554</us-gaap:FiniteLivedIntangibleAssetsAccumulatedAmortization>
    <us-gaap:AdjustmentForAmortization
      contextRef="From2020-07-012020-09-30_custom_EGENIncMember_custom_PurchaseAgreementMember"
      decimals="0"
      unitRef="USD">56830</us-gaap:AdjustmentForAmortization>
    <us-gaap:AdjustmentForAmortization
      contextRef="From2020-01-012020-09-30_custom_EGENIncMember_custom_PurchaseAgreementMember"
      decimals="0"
      unitRef="USD">170487</us-gaap:AdjustmentForAmortization>
    <us-gaap:GoodwillAcquiredDuringPeriod
      contextRef="From2021-01-012021-09-30_custom_EGENIncMember"
      decimals="-5"
      unitRef="USD">2000000.0</us-gaap:GoodwillAcquiredDuringPeriod>
    <us-gaap:FiniteLivedAndIndefiniteLivedIntangibleAssetsAcquiredAsPartOfBusinessCombinationTableTextBlock contextRef="From2021-01-01to2021-09-30">&lt;p id="xdx_898_eus-gaap--FiniteLivedAndIndefiniteLivedIntangibleAssetsAcquiredAsPartOfBusinessCombinationTableTextBlock_zXDuovtJEQXe" style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Following
is a summary of the net fair value of the assets acquired in the EGEN asset acquisition for the nine-month period ended September 30,
2021:&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;span id="xdx_8B0_z0EHPjzNCcKb" style="display: none"&gt;Schedule of Fair Value of Assets Acquired&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; border-collapse: collapse; width: 100%"&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td style="text-align: center"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;IPR&amp;amp;D&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;Goodwill&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;Covenant Not To Compete&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="font-weight: bold"&gt;For the nine-months ended September 30, 2021&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="width: 55%; text-align: left"&gt;Balance at January 1, 2021, net&lt;/td&gt;&lt;td style="width: 2%"&gt;&#160;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_98E_eus-gaap--FiniteLivedIntangibleAssetsNet_iS_pp0p0_c20210101__20210930__us-gaap--FairValueByAssetClassAxis__custom--IPRAndDMember_zq7Dgx9SsUVc" style="width: 11%; text-align: right" title="Intangible assets, beginning balance"&gt;13,366,234&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="width: 2%"&gt;&#160;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_98B_eus-gaap--FiniteLivedIntangibleAssetsNet_iS_pp0p0_c20210101__20210930__us-gaap--FairValueByAssetClassAxis__us-gaap--GoodwillMember_z0J0mdcEYax9" style="width: 11%; text-align: right" title="Intangible assets, beginning balance"&gt;1,976,101&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="width: 2%"&gt;&#160;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_983_eus-gaap--FiniteLivedIntangibleAssetsNet_iS_pp0p0_c20210101__20210930__us-gaap--FiniteLivedIntangibleAssetsByMajorClassAxis__us-gaap--NoncompeteAgreementsMember_zpqj3DmNvL4l" style="width: 11%; text-align: right" title="Intangible assets, beginning balance"&gt;113,660&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="padding-bottom: 1.5pt"&gt;Amortization&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_98F_eus-gaap--AmortizationOfIntangibleAssets_c20210101__20210930__us-gaap--FairValueByAssetClassAxis__custom--IPRAndDMember_pp0p0" style="border-bottom: Black 1.5pt solid; text-align: right" title="Amortization"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl1065"&gt;-&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_984_eus-gaap--AmortizationOfIntangibleAssets_c20210101__20210930__us-gaap--FairValueByAssetClassAxis__us-gaap--GoodwillMember_pp0p0" style="border-bottom: Black 1.5pt solid; text-align: right" title="Amortization"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl1067"&gt;-&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_98F_eus-gaap--AmortizationOfIntangibleAssets_c20210101__20210930__us-gaap--FiniteLivedIntangibleAssetsByMajorClassAxis__us-gaap--NoncompeteAgreementsMember_pp0p0" style="border-bottom: Black 1.5pt solid; text-align: right" title="Amortization"&gt;(113,660&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;)&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left; padding-bottom: 2.5pt"&gt;Balance at September 30, 2021, net&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_984_eus-gaap--FiniteLivedIntangibleAssetsNet_iE_pp0p0_c20210101__20210930__us-gaap--FairValueByAssetClassAxis__custom--IPRAndDMember_zFup0rr4aQHa" style="border-bottom: Black 2.5pt double; text-align: right" title="Intangible assets, ending balance"&gt;13,366,234&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_98A_eus-gaap--FiniteLivedIntangibleAssetsNet_iE_pp0p0_c20210101__20210930__us-gaap--FairValueByAssetClassAxis__us-gaap--GoodwillMember_z8vEWj0X076d" style="border-bottom: Black 2.5pt double; text-align: right" title="Intangible assets, ending balance"&gt;1,976,101&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_98D_eus-gaap--FiniteLivedIntangibleAssetsNet_iE_pp0p0_c20210101__20210930__us-gaap--FiniteLivedIntangibleAssetsByMajorClassAxis__us-gaap--NoncompeteAgreementsMember_zSULCWREzVBl" style="border-bottom: Black 2.5pt double; text-align: right" title="Intangible assets, ending balance"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl1075"&gt;-&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;

</us-gaap:FiniteLivedAndIndefiniteLivedIntangibleAssetsAcquiredAsPartOfBusinessCombinationTableTextBlock>
    <us-gaap:FiniteLivedIntangibleAssetsNet
      contextRef="AsOf2020-12-31_custom_IPRAndDMember"
      decimals="0"
      unitRef="USD">13366234</us-gaap:FiniteLivedIntangibleAssetsNet>
    <us-gaap:FiniteLivedIntangibleAssetsNet
      contextRef="AsOf2020-12-31_us-gaap_GoodwillMember"
      decimals="0"
      unitRef="USD">1976101</us-gaap:FiniteLivedIntangibleAssetsNet>
    <us-gaap:FiniteLivedIntangibleAssetsNet
      contextRef="AsOf2020-12-31_us-gaap_NoncompeteAgreementsMember"
      decimals="0"
      unitRef="USD">113660</us-gaap:FiniteLivedIntangibleAssetsNet>
    <us-gaap:AmortizationOfIntangibleAssets
      contextRef="From2021-01-012021-09-30_us-gaap_NoncompeteAgreementsMember"
      decimals="0"
      unitRef="USD">-113660</us-gaap:AmortizationOfIntangibleAssets>
    <us-gaap:FiniteLivedIntangibleAssetsNet
      contextRef="AsOf2021-09-30_custom_IPRAndDMember"
      decimals="0"
      unitRef="USD">13366234</us-gaap:FiniteLivedIntangibleAssetsNet>
    <us-gaap:FiniteLivedIntangibleAssetsNet
      contextRef="AsOf2021-09-30_us-gaap_GoodwillMember"
      decimals="0"
      unitRef="USD">1976101</us-gaap:FiniteLivedIntangibleAssetsNet>
    <us-gaap:AccountsPayableAndAccruedLiabilitiesDisclosureTextBlock contextRef="From2021-01-01to2021-09-30">&lt;p id="xdx_80C_eus-gaap--AccountsPayableAndAccruedLiabilitiesDisclosureTextBlock_zKKKIBQt2Djh" style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Note
10. &lt;span id="xdx_829_zgU3zWli6Nl3"&gt;Accrued Liabilities&lt;/span&gt;&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p id="xdx_896_eus-gaap--ScheduleOfAccruedLiabilitiesTableTextBlock_zFRfWdh5Oete" style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Other
accrued liabilities at September 30, 2021 and December 31, 2020 include the following:&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;span id="xdx_8BA_z61et2nki4me" style="display: none"&gt;Schedule of Accrued Liabilities&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; border-collapse: collapse; width: 100%"&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td style="text-align: center"&gt;&#160;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" id="xdx_49E_20210930_z9bnF7D3JD9c" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;September 30, 2021&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&#160;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" id="xdx_499_20201231_zt9ssufceVvi" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;December 31, 2020&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_403_eus-gaap--ContractualObligation_iI_pp0p0_maALCzQkn_zbz4pLF55sd" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="width: 60%; text-align: left"&gt;Amounts due to contract research organizations and other contractual agreements&lt;/td&gt;&lt;td style="width: 2%"&gt;&#160;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;$&lt;/td&gt;&lt;td style="width: 16%; text-align: right"&gt;1,276,317&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="width: 2%"&gt;&#160;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;$&lt;/td&gt;&lt;td style="width: 16%; text-align: right"&gt;636,000&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_40D_eus-gaap--EmployeeRelatedLiabilitiesCurrent_iI_pp0p0_maALCzQkn_z552WQxhvgh9" style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left"&gt;Accrued payroll and related benefits&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;1,247,460&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;1,736,271&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_408_eus-gaap--AccruedProfessionalFeesCurrent_iI_pp0p0_maALCzQkn_zKZyPCLmQn8k" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left"&gt;Accrued professional fees&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;265,350&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;66,850&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_40B_eus-gaap--InterestPayableCurrent_iI_pp0p0_maALCzQkn_zb4QIRBEAODl" style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left"&gt;Accrued interest&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;16,250&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl1091"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;-&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_40C_eus-gaap--OtherAccruedLiabilitiesCurrent_iI_pp0p0_maALCzQkn_z7ht5o6V1M8k" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="padding-bottom: 1.5pt"&gt;Other&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="border-bottom: Black 1.5pt solid; text-align: right"&gt;19,411&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="border-bottom: Black 1.5pt solid; text-align: right"&gt;19,411&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_403_eus-gaap--AccruedLiabilitiesCurrent_iTI_pp0p0_mtALCzQkn_zWjBndk603P5" style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="padding-bottom: 2.5pt"&gt;Total&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;$&lt;/td&gt;&lt;td style="border-bottom: Black 2.5pt double; text-align: right"&gt;2,824,788&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;$&lt;/td&gt;&lt;td style="border-bottom: Black 2.5pt double; text-align: right"&gt;2,458,532&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;

&lt;p id="xdx_8A5_zH1rinWQshj2" style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"/&gt;&lt;/p&gt;



&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

</us-gaap:AccountsPayableAndAccruedLiabilitiesDisclosureTextBlock>
    <us-gaap:ScheduleOfAccruedLiabilitiesTableTextBlock contextRef="From2021-01-01to2021-09-30">&lt;p id="xdx_896_eus-gaap--ScheduleOfAccruedLiabilitiesTableTextBlock_zFRfWdh5Oete" style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Other
accrued liabilities at September 30, 2021 and December 31, 2020 include the following:&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;span id="xdx_8BA_z61et2nki4me" style="display: none"&gt;Schedule of Accrued Liabilities&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; border-collapse: collapse; width: 100%"&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td style="text-align: center"&gt;&#160;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" id="xdx_49E_20210930_z9bnF7D3JD9c" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;September 30, 2021&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&#160;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" id="xdx_499_20201231_zt9ssufceVvi" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;December 31, 2020&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_403_eus-gaap--ContractualObligation_iI_pp0p0_maALCzQkn_zbz4pLF55sd" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="width: 60%; text-align: left"&gt;Amounts due to contract research organizations and other contractual agreements&lt;/td&gt;&lt;td style="width: 2%"&gt;&#160;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;$&lt;/td&gt;&lt;td style="width: 16%; text-align: right"&gt;1,276,317&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="width: 2%"&gt;&#160;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;$&lt;/td&gt;&lt;td style="width: 16%; text-align: right"&gt;636,000&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_40D_eus-gaap--EmployeeRelatedLiabilitiesCurrent_iI_pp0p0_maALCzQkn_z552WQxhvgh9" style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left"&gt;Accrued payroll and related benefits&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;1,247,460&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;1,736,271&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_408_eus-gaap--AccruedProfessionalFeesCurrent_iI_pp0p0_maALCzQkn_zKZyPCLmQn8k" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left"&gt;Accrued professional fees&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;265,350&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;66,850&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_40B_eus-gaap--InterestPayableCurrent_iI_pp0p0_maALCzQkn_zb4QIRBEAODl" style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left"&gt;Accrued interest&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;16,250&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl1091"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;-&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_40C_eus-gaap--OtherAccruedLiabilitiesCurrent_iI_pp0p0_maALCzQkn_z7ht5o6V1M8k" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="padding-bottom: 1.5pt"&gt;Other&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="border-bottom: Black 1.5pt solid; text-align: right"&gt;19,411&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="border-bottom: Black 1.5pt solid; text-align: right"&gt;19,411&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_403_eus-gaap--AccruedLiabilitiesCurrent_iTI_pp0p0_mtALCzQkn_zWjBndk603P5" style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="padding-bottom: 2.5pt"&gt;Total&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;$&lt;/td&gt;&lt;td style="border-bottom: Black 2.5pt double; text-align: right"&gt;2,824,788&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;$&lt;/td&gt;&lt;td style="border-bottom: Black 2.5pt double; text-align: right"&gt;2,458,532&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;

</us-gaap:ScheduleOfAccruedLiabilitiesTableTextBlock>
    <us-gaap:ContractualObligation contextRef="AsOf2021-09-30" decimals="0" unitRef="USD">1276317</us-gaap:ContractualObligation>
    <us-gaap:ContractualObligation contextRef="AsOf2020-12-31" decimals="0" unitRef="USD">636000</us-gaap:ContractualObligation>
    <us-gaap:EmployeeRelatedLiabilitiesCurrent contextRef="AsOf2021-09-30" decimals="0" unitRef="USD">1247460</us-gaap:EmployeeRelatedLiabilitiesCurrent>
    <us-gaap:EmployeeRelatedLiabilitiesCurrent contextRef="AsOf2020-12-31" decimals="0" unitRef="USD">1736271</us-gaap:EmployeeRelatedLiabilitiesCurrent>
    <us-gaap:AccruedProfessionalFeesCurrent contextRef="AsOf2021-09-30" decimals="0" unitRef="USD">265350</us-gaap:AccruedProfessionalFeesCurrent>
    <us-gaap:AccruedProfessionalFeesCurrent contextRef="AsOf2020-12-31" decimals="0" unitRef="USD">66850</us-gaap:AccruedProfessionalFeesCurrent>
    <us-gaap:InterestPayableCurrent contextRef="AsOf2021-09-30" decimals="0" unitRef="USD">16250</us-gaap:InterestPayableCurrent>
    <us-gaap:OtherAccruedLiabilitiesCurrent contextRef="AsOf2021-09-30" decimals="0" unitRef="USD">19411</us-gaap:OtherAccruedLiabilitiesCurrent>
    <us-gaap:OtherAccruedLiabilitiesCurrent contextRef="AsOf2020-12-31" decimals="0" unitRef="USD">19411</us-gaap:OtherAccruedLiabilitiesCurrent>
    <us-gaap:AccruedLiabilitiesCurrent contextRef="AsOf2021-09-30" decimals="0" unitRef="USD">2824788</us-gaap:AccruedLiabilitiesCurrent>
    <us-gaap:AccruedLiabilitiesCurrent contextRef="AsOf2020-12-31" decimals="0" unitRef="USD">2458532</us-gaap:AccruedLiabilitiesCurrent>
    <us-gaap:DebtDisclosureTextBlock contextRef="From2021-01-01to2021-09-30">&lt;p id="xdx_809_eus-gaap--DebtDisclosureTextBlock_zmzFPnNQmkQ" style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Note
11. &lt;span id="xdx_82A_z4yFz4Yu7HTf"&gt;Notes Payable&lt;/span&gt;&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;i&gt;The
SVB Loan Facility&lt;/i&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;On
June 18, 2021, the Company entered into a $&lt;span id="xdx_903_eus-gaap--LineOfCreditFacilityMaximumBorrowingCapacity_c20210618__us-gaap--TypeOfArrangementAxis__custom--SVBLoanFacilityMember_pn6n6" title="Line of Credit Facility, Maximum Borrowing Capacity"&gt;10&lt;/span&gt; million loan facility (the &#x201c;SVB Loan Facility&#x201d;) with Silicon Valley Bank (&#x201c;SVB&#x201d;).
Celsion immediately used $&lt;span id="xdx_90C_eus-gaap--ProceedsFromLinesOfCredit_c20210601__20210618__us-gaap--TypeOfArrangementAxis__custom--SVBLoanFacilityMember_pn6n6" title="Proceeds from Lines of Credit"&gt;6&lt;/span&gt; million from the SVB Loan Facility to retire all outstanding indebtedness with Horizon Technology Finance
Corporation as further discussed below. Concurrently with this transaction, the Company used $&lt;span id="xdx_908_eus-gaap--RestrictedCash_c20210618__us-gaap--TypeOfArrangementAxis__custom--SVBLoanFacilityMember_pn6n6" title="Restricted cash"&gt;6.0&lt;/span&gt; million of other available funds to
establish a restricted cash account which serves as security for the SVB Loan Facility. The remaining $&lt;span id="xdx_904_eus-gaap--LineOfCreditFacilityRemainingBorrowingCapacity_c20210618__us-gaap--TypeOfArrangementAxis__custom--SVBLoanFacilityMember_pn6n6" title="Line of Credit Facility, Remaining Borrowing Capacity"&gt;4&lt;/span&gt; million will be available to
be drawn down up to 12 months after closing and will be used for working capital and to fund the advancement of the Company&#x2019;s product
pipeline, including GEN-1 for the treatment of newly diagnosed advanced ovarian cancer, as well as other strategic initiatives intended
to broaden its product pipeline.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;The
SVB Loan Facility is in the form of money market secured indebtedness bearing interest at a calculated WSJ Prime-based variable rate
(currently &lt;span id="xdx_905_eus-gaap--DebtInstrumentInterestRateStatedPercentage_iI_pid_dp_uPure_c20210618__us-gaap--TypeOfArrangementAxis__custom--SVBLoanFacilityMember_zwiIfhzGJet6" title="Debt Instrument, Interest Rate, Stated Percentage"&gt;3.25&lt;/span&gt;%). A final payment equal to &lt;span id="xdx_900_ecustom--FinalPaymentPercentage_iI_pid_dp_uPure_c20210618__us-gaap--TypeOfArrangementAxis__custom--SVBLoanFacilityMember_zSgQWtx1jYh5" title="Final payment percentage"&gt;3&lt;/span&gt;% of the total $&lt;span id="xdx_907_eus-gaap--LineOfCredit_c20210618__us-gaap--TypeOfArrangementAxis__custom--SVBLoanFacilityMember_pn6n6" title="Long-term Line of Credit"&gt;10&lt;/span&gt; million commitment amount is due upon maturity or prepayment of the SVB
Loan Facility. There was no facility commitment fee and no stock or warrants were issued to SVB. &lt;span id="xdx_903_eus-gaap--DebtInstrumentDescription_c20210601__20210618__us-gaap--TypeOfArrangementAxis__custom--SVBLoanFacilityMember" title="Debt Instrument, Description"&gt;Payments under the loan agreement are
interest only for the first 24 months after loan closing, followed by a 24-month amortization period of principal and interest through
the scheduled maturity date.&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;In
connection with the SVB Loan Facility, the Company incurred financing fees and expenses totaling $&lt;span id="xdx_901_eus-gaap--InterestAndDebtExpense_pp0p0_c20210601__20210618__us-gaap--TypeOfArrangementAxis__custom--SVBLoanFacilityMember_zd1cNJltzmH5" title="Interest and Debt Expense"&gt;243,370&lt;/span&gt; which is recorded and classified
as debt discount and are being amortized as interest expense using the effective interest method over the life of the loan. Also, in
connection with the SVB Loan Facility, the Company is required to pay an end-of-term fee equal to &lt;span id="xdx_901_ecustom--EndOfTermChargePercentage_pid_dp_uPure_c20210601__20210618__us-gaap--TypeOfArrangementAxis__custom--SVBLoanFacilityMember_z4fko1Q6sIsd" title="End of term charge percentage"&gt;3.0&lt;/span&gt;% of the original loan amount at
time of maturity. Therefore, these amounts totaling $&lt;span id="xdx_90A_eus-gaap--AmortizationOfFinancingCosts_pp0p0_c20210601__20210618__us-gaap--TypeOfArrangementAxis__custom--SVBLoanFacilityMember_zaX0j7MymNEh" title="Amortization of Debt Issuance Costs"&gt;300,000&lt;/span&gt; are being amortized as interest expense using the effective interest method
over the life of the loan. During the three-month and nine-month periods ended September 30, 2021, the Company incurred interest expense
of $&lt;span id="xdx_902_eus-gaap--InterestExpenseDebt_pp0p0_c20210701__20210930__us-gaap--TypeOfArrangementAxis__custom--SVBLoanFacilityMember_zPzshv0B9psb" title="Interest Expense, Debt"&gt;49,883&lt;/span&gt; and $&lt;span id="xdx_90B_eus-gaap--InterestExpenseDebt_pp0p0_c20210101__20210930__us-gaap--TypeOfArrangementAxis__custom--SVBLoanFacilityMember_znWsC9ozecAc" title="Interest Expense, Debt"&gt;56,875&lt;/span&gt;, respectively, and amortized $&lt;span id="xdx_90A_eus-gaap--AmortizationOfFinancingCostsAndDiscounts_pp0p0_c20210701__20210930__us-gaap--TypeOfArrangementAxis__custom--SVBLoanFacilityMember_zBC0koYu7Hq4" title="Amortization of Debt Issuance Costs and Discounts"&gt;45,687&lt;/span&gt; and $&lt;span id="xdx_90A_eus-gaap--AmortizationOfFinancingCostsAndDiscounts_pp0p0_c20210101__20210930__us-gaap--TypeOfArrangementAxis__custom--SVBLoanFacilityMember_z9Nty0okMk1d" title="Amortization of Debt Issuance Costs and Discounts"&gt;52,144&lt;/span&gt;, respectively, as interest expense for debt discounts and end-of-term
fee in connection with the SVB Financing Facility.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p id="xdx_892_eus-gaap--ScheduleOfMaturitiesOfLongTermDebtTableTextBlock_zXtImcS3lVzd" style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Following
is a schedule of future principal payments, net of unamortized debt discounts and amortized end-of-term fee, due on the SVB Loan Facility:&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;span id="xdx_8B5_zKg8XUhRLq73" style="display: none"&gt;Schedule of Future Principle Payments, Net of Unamortized Debt Discounts&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; margin-left: auto; border-collapse: collapse; width: 80%; margin-right: auto"&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" id="xdx_496_20210930_zVIigqYXYyUh" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;As of &lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;September 30,&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_402_eus-gaap--LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths_iI_pp0p0_maDICAzbmk_zg2ckJTrSEBc" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left"&gt;2022&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;$&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl1133"&gt;&#x2013;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_406_eus-gaap--LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo_iI_pp0p0_maDICAzbmk_zZZhOad9o9Hk" style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="width: 74%; text-align: left"&gt;2023&lt;/td&gt;&lt;td style="width: 2%"&gt;&#160;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="width: 22%; text-align: right"&gt;750,000&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_409_eus-gaap--LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree_iI_pp0p0_maDICAzbmk_zLvwzQ02hapj" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left"&gt;2024&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;3,000,000&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_403_ecustom--LongTermDebtMaturitiesRepaymentsOfPrincipalYearFourAndThereAfter_iI_pp0p0_maDICAzbmk_zkQjMgBCaOD6" style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;2025 and thereafter&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="border-bottom: Black 1.5pt solid; text-align: right"&gt;2,250,000&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_406_eus-gaap--DebtInstrumentCarryingAmount_iTI_pp0p0_mtDICAzbmk_maLTDzyWo_zskOsYCmouo3" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Subtotal of future principal payments&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;6,000,000&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_401_eus-gaap--DeferredFinanceCostsNet_iNI_pp0p0_di_msLTDzyWo_z42UJjJJQXP1" style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Unamortized debt premium, net&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="border-bottom: Black 1.5pt solid; text-align: right"&gt;(191,226&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;)&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_404_eus-gaap--LongTermDebt_iTI_pp0p0_mtLTDzyWo_z4lvv0gQZC0k" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="padding-left: 10pt; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Total&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;$&lt;/td&gt;&lt;td style="border-bottom: Black 2.5pt double; text-align: right"&gt;5,808,774&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;

&lt;p id="xdx_8AD_zHJVhOSDvSp6" style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;i&gt;Horizon
Credit Agreement&lt;/i&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;On
June 27, 2018, the Company entered into a loan agreement with Horizon Technology Finance Corporation (&#x201c;Horizon&#x201d;) that provided
$&lt;span id="xdx_90F_eus-gaap--LineOfCreditFacilityMaximumBorrowingCapacity_c20180627__us-gaap--TypeOfArrangementAxis__custom--InitialHorizonCreditAgreementMember_pn6n6" title="Line of Credit Facility, Maximum Borrowing Capacity"&gt;10&lt;/span&gt; million in new capital (the &#x201c;Horizon Credit Agreement&#x201d;). The Company drew down $&lt;span id="xdx_901_eus-gaap--ProceedsFromLinesOfCredit_c20180626__20180627__us-gaap--TypeOfArrangementAxis__custom--InitialHorizonCreditAgreementMember_pn6n6" title="Proceeds from Lines of Credit"&gt;10&lt;/span&gt; million upon closing of the Horizon
Credit Agreement on June 27, 2018. On August 28, 2020, Horizon and the Company amended the Horizon Credit Agreement (the &#x201c;Amendment&#x201d;)
whereby Celsion repaid $&lt;span id="xdx_908_eus-gaap--LineOfCreditFacilityRemainingBorrowingCapacity_c20180627__us-gaap--TypeOfArrangementAxis__custom--InitialHorizonCreditAgreementMember_pn6n6" title="Line of Credit Facility, Remaining Borrowing Capacity"&gt;5&lt;/span&gt; million of the $10 million loan and $&lt;span id="xdx_905_ecustom--PaymentOfDebtEndTermCharges_pn5n6_c20200827__20200828__us-gaap--TypeOfArrangementAxis__custom--AmendmentToHorizonCreditAgreementMember__dei--LegalEntityAxis__custom--HorizonTechnologyFinanceCorporationMember_z0QsaML20Oj5"&gt;0.2&lt;/span&gt; million in related end of term charges, and the remaining $&lt;span id="xdx_90C_eus-gaap--LineOfCreditFacilityRemainingBorrowingCapacity_iI_pn6n6_c20180627__us-gaap--TypeOfArrangementAxis__custom--InitialHorizonCreditAgreementMember_zna17zWExjza"&gt;5&lt;/span&gt; million
in obligations were restructured as set forth below.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Pursuant
to the Amendment, the remaining $&lt;span id="xdx_906_eus-gaap--DebtInstrumentFaceAmount_iI_pn6n6_c20200828__us-gaap--TypeOfArrangementAxis__custom--AmendmentToHorizonCreditAgreementMember__dei--LegalEntityAxis__custom--HorizonTechnologyFinanceCorporationMember_z03xOz8j8344" title="Debt Instrument, Face Amount"&gt;5&lt;/span&gt; million in obligations of Celsion under the Horizon Credit Agreement was secured by a first-priority
security interest in substantially all assets of Celsion other than intellectual property assets. &lt;span id="xdx_900_eus-gaap--DebtInstrumentInterestRateTerms_c20200827__20200828__us-gaap--TypeOfArrangementAxis__custom--AmendmentToHorizonCreditAgreementMember__dei--LegalEntityAxis__custom--HorizonTechnologyFinanceCorporationMember" title="Debt Instrument, Interest Rate Terms"&gt;The obligations bore interest at a
rate calculated based an amount by which the one-month LIBOR exceeds 2% plus 7.625%. In no event shall the interest rate be less than
9.625%. Payments pursuant to the Amendment were interest only for the first twelve (12) months after August 1, 2020, followed by a 21-month
amortization period of principal and interest through the scheduled maturity date on April 1, 2023. In addition, the remaining $&lt;span id="xdx_909_eus-gaap--PaymentsOfDebtExtinguishmentCosts_c20200827__20200828__us-gaap--TypeOfArrangementAxis__custom--AmendmentToHorizonCreditAgreementMember__dei--LegalEntityAxis__custom--HorizonTechnologyFinanceCorporationMember_pn6n6" title="Payment for Debt Extinguishment or Debt Prepayment Cost"&gt;5&lt;/span&gt; million
in obligations was subject to an end of term fee equal, in the aggregate, to $&lt;span id="xdx_909_eus-gaap--DebtInstrumentFeeAmount_iI_pp0p0_c20200828__us-gaap--TypeOfArrangementAxis__custom--AmendmentToHorizonCreditAgreementMember__dei--LegalEntityAxis__custom--HorizonTechnologyFinanceCorporationMember_zD6yKW8dB5l5" title="Debt Instrument, Fee Amount"&gt;275,000&lt;/span&gt;, which amount was payable upon the maturity of
the obligations or upon the date of final payment or default, as applicable.&lt;/span&gt; &lt;span id="xdx_90C_eus-gaap--DebtInstrumentRestrictiveCovenants_c20200827__20200828__us-gaap--TypeOfArrangementAxis__custom--AmendmentToHorizonCreditAgreementMember__dei--LegalEntityAxis__custom--HorizonTechnologyFinanceCorporationMember" title="Debt Instrument, Restrictive Covenants"&gt;In connection with the Amendment, Celsion agreed to a liquidity
covenant which provides that, at all times, Celsion shall maintain unrestricted cash and/or cash equivalents on deposit in accounts over
which the applicable Lenders maintain an account control agreement in an amount not less than $2.5 million. In addition, pursuant to
the Amendment, Celsion agreed to provide evidence to Horizon on or before March 31, 2021, that it received aggregate cash proceeds of
not less than $5 million from the sale of equity, debt, its New Jersey net operating losses, or a combination thereof, subsequent to
the date of the Amendment. The Company met this requirement during the fourth quarter of 2020.&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;



&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"/&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;In
connection with the Horizon Credit Agreement, the Company incurred financing fees and expenses totaling $&lt;span id="xdx_90C_eus-gaap--InterestAndDebtExpense_c20180626__20180627__us-gaap--TypeOfArrangementAxis__custom--InitialHorizonCreditAgreementMember_pp0p0"&gt;175,000&lt;/span&gt; which were recorded
and classified as debt discount. In addition, the Company paid loan origination fees of $&lt;span id="xdx_908_eus-gaap--LoanProcessingFee_pp0p0_c20180626__20180627__us-gaap--TypeOfArrangementAxis__custom--InitialHorizonCreditAgreementMember_ziChZRsSUWOj" title="Loan Processing Fee"&gt;100,000&lt;/span&gt; which were recorded and classified as
debt discount. These debt discount amounts totaling $&lt;span id="xdx_90B_eus-gaap--DebtInstrumentUnamortizedDiscount_iI_pp0p0_c20180627__us-gaap--TypeOfArrangementAxis__custom--InitialHorizonCreditAgreementMember_zVdR9iqsTnM6" title="Debt Instrument, Unamortized Discount"&gt;782,116&lt;/span&gt; were being amortized as interest expense using the effective interest method
over the life of the loan. Also, in connection with each of the Horizon Credit Agreement, the Company was required to pay an end of term
charge equal to &lt;span id="xdx_90E_ecustom--EndOfTermChargePercentage_pid_dp_uPure_c20180626__20180627__us-gaap--TypeOfArrangementAxis__custom--InitialHorizonCreditAgreementMember_zVdc3L4T94d4"&gt;4.0&lt;/span&gt;% of the original loan amount at time of maturity. Therefore, those amounts totaling $&lt;span id="xdx_909_eus-gaap--DeferredFinanceCostsNet_iI_pp0p0_c20180627__us-gaap--TypeOfArrangementAxis__custom--InitialHorizonCreditAgreementMember_zqwad6jUyb77" title="Debt Issuance Costs, Net"&gt;400,000&lt;/span&gt; were being amortized
as interest expense using the effective interest method over the life of the loan.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;As
a fee in connection with the Horizon Credit Agreement, Celsion issued Horizon warrants exercisable for a total of &lt;span id="xdx_904_eus-gaap--ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights_c20180627__us-gaap--TypeOfArrangementAxis__custom--InitialHorizonCreditAgreementMember__us-gaap--StatementEquityComponentsAxis__us-gaap--CommonStockMember_pdd" title="Class of Warrant or Right, Number of Securities Called by Warrants or Rights"&gt;190,114&lt;/span&gt; shares of Celsion&#x2019;s
common stock (the &#x201c;Existing Warrants&#x201d;) at a per share exercise price of $&lt;span id="xdx_907_eus-gaap--ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1_c20180627__us-gaap--TypeOfArrangementAxis__custom--InitialHorizonCreditAgreementMember__us-gaap--StatementEquityComponentsAxis__us-gaap--CommonStockMember_pdd" title="Class of Warrant or Right, Exercise Price of Warrants or Rights"&gt;2.63&lt;/span&gt;. The Horizon Warrants were immediately exercisable
for cash or by net exercise from the date of grant and will expire after ten years from the date of grant. The Company valued the Horizon
Warrants issued using the Black-Scholes option pricing model and recorded a total of $&lt;span id="xdx_90B_eus-gaap--FairValueAdjustmentOfWarrants_c20180626__20180627__us-gaap--TypeOfArrangementAxis__custom--InitialHorizonCreditAgreementMember_pp0p0"&gt;507,116&lt;/span&gt; as a direct deduction from the debt liability,
consistent with the presentation of debt discounts, and are being amortized as interest expense using the effective interest method over
the life of the loan. Pursuant to the Amendment, one-half of the aggregate Existing Warrants, exercisable for a total of &lt;span id="xdx_904_eus-gaap--ClassOfWarrantOrRightOutstanding_c20180627__us-gaap--TypeOfArrangementAxis__custom--InitialHorizonCreditAgreementMember__us-gaap--StatementEquityComponentsAxis__us-gaap--CommonStockMember_pdd" title="Class of Warrant or Right, Outstanding"&gt;95,057&lt;/span&gt; shares
of Celsion&#x2019;s common stock, have been canceled, and, in connection with the Amendment, Celsion issued Horizon new warrants exercisable
at a per share exercise price equal to $&lt;span id="xdx_906_eus-gaap--ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1_c20200828__us-gaap--TypeOfArrangementAxis__custom--AmendmentToHorizonCreditAgreementMember__dei--LegalEntityAxis__custom--HorizonTechnologyFinanceCorporationMember__us-gaap--StatementEquityComponentsAxis__us-gaap--CommonStockMember_pdd" title="Class of Warrant or Right, Exercise Price of Warrants or Rights"&gt;1.01&lt;/span&gt; for a total of &lt;span id="xdx_904_eus-gaap--ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights_c20200828__us-gaap--TypeOfArrangementAxis__custom--AmendmentToHorizonCreditAgreementMember__dei--LegalEntityAxis__custom--HorizonTechnologyFinanceCorporationMember__us-gaap--StatementEquityComponentsAxis__us-gaap--CommonStockMember_pdd" title="Class of Warrant or Right, Number of Securities Called by Warrants or Rights"&gt;247,525&lt;/span&gt; shares of Celsion&#x2019;s common stock (the &#x201c;New Warrants&#x201d;
and, together with the Existing Warrants, the &#x201c;Warrants&#x201d;). The remaining &lt;span id="xdx_903_ecustom--ClassOfWarrantOrRightWarrantsOrRightsCancelled_c20200828__us-gaap--TypeOfArrangementAxis__custom--AmendmentToHorizonCreditAgreementMember__dei--LegalEntityAxis__custom--HorizonTechnologyFinanceCorporationMember__us-gaap--StatementEquityComponentsAxis__us-gaap--CommonStockMember_pdd" title="Warrants cancelled"&gt;95,057&lt;/span&gt; Existing Warrants issued in connection with
the Horizon Credit Agreement remain outstanding at a per share exercise price of $2.63.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;The
New Warrants were immediately exercisable for cash or by net exercise from the date of grant and will expire after ten years from the
date of grant. The Horizon Credit Agreement contains customary representations, warranties and affirmative and negative covenants including,
among other things, covenants that limit or restrict Celsion&#x2019;s ability to grant liens, incur indebtedness, make certain restricted
payments, merge, or consolidate and make dispositions of assets.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;The
Amendment was evaluated in accordance with FASB ASC 470-50, &lt;i&gt;Debt-Modifications and Extinguishments&lt;/i&gt;, for debt modification and
extinguishment accounting. We accounted for the $&lt;span id="xdx_904_eus-gaap--PaymentsOfDebtExtinguishmentCosts_pn6n6_c20200827__20200828__us-gaap--TypeOfArrangementAxis__custom--AmendmentToHorizonCreditAgreementMember__dei--LegalEntityAxis__custom--HorizonTechnologyFinanceCorporationMember_zQzGyrT4dKxh"&gt;5&lt;/span&gt; million we repaid as a debt extinguishment thereby reducing the principal obligations
accordingly. Also, in connection with the $5 million repayment, we recognized as interest expense, approximately $&lt;span id="xdx_909_eus-gaap--DebtInstrumentUnamortizedDiscount_iI_pn5n6_c20200828__us-gaap--TypeOfArrangementAxis__custom--AmendmentToHorizonCreditAgreementMember__dei--LegalEntityAxis__custom--HorizonTechnologyFinanceCorporationMember_zg2hMNYQCgA1"&gt;0.2&lt;/span&gt; million of unamortized
debt discount, deferred financing and end of term fees related to the repaid obligation in August 2020.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;We
accounted for the remaining $&lt;span id="xdx_909_eus-gaap--DebtInstrumentFaceAmount_iI_pn6n6_c20200828__us-gaap--TypeOfArrangementAxis__custom--AmendmentToHorizonCreditAgreementMember__dei--LegalEntityAxis__custom--HorizonTechnologyFinanceCorporationMember_zNNZQkto9NPd" title="Debt instrument face amount"&gt;5&lt;/span&gt; million of obligation under the Amendment as a debt modification to the initial agreement with respect
to the minor changes in cash flows. Also, in connection with the $5 million remaining obligations, we recorded $&lt;span id="xdx_900_eus-gaap--DeferredFinanceCostsNet_iI_pp0p0_c20200828__us-gaap--TypeOfArrangementAxis__custom--AmendmentToHorizonCreditAgreementMember__dei--LegalEntityAxis__custom--HorizonTechnologyFinanceCorporationMember_ztNwFdB1IiZ6"&gt;5,000&lt;/span&gt; of financing fees
and the New Warrant fair value of $&lt;span id="xdx_904_eus-gaap--WarrantsNotSettleableInCashFairValueDisclosure_iI_pp0p0_c20200828__us-gaap--TypeOfArrangementAxis__custom--AmendmentToHorizonCreditAgreementMember__dei--LegalEntityAxis__custom--HorizonTechnologyFinanceCorporationMember_zS8hXvcvyDCe" title="Warrants Not Settleable in Cash, Fair Value Disclosure"&gt;247,548&lt;/span&gt; as additional debt discount on the $5 million remaining obligation. Therefore, approximately
$&lt;span id="xdx_902_eus-gaap--DebtInstrumentUnamortizedDiscount_c20210630__us-gaap--TypeOfArrangementAxis__custom--AmendmentToHorizonCreditAgreementMember__dei--LegalEntityAxis__custom--HorizonTechnologyFinanceCorporationMember_pp0p0"&gt;109,706&lt;/span&gt; of unamortized debt discount will be amortized over the remaining life of the new obligations. The $&lt;span id="xdx_906_ecustom--EndOfTermFees_pp0p0_c20180626__20180627__us-gaap--TypeOfArrangementAxis__custom--InitialHorizonCreditAgreementMember_zXF75WSf6Ov8" title="End of term fees"&gt;275,000&lt;/span&gt; of end of term fees,
net of previously amortized end of term fees totaling $&lt;span id="xdx_908_eus-gaap--DebtInstrumentFeeAmount_c20180627__us-gaap--TypeOfArrangementAxis__custom--InitialHorizonCreditAgreementMember_pp0p0"&gt;142,605&lt;/span&gt; previously accrued on the original note associated with the $5 million
remaining obligation, will be amortized as interest expense over the remaining life of the new obligations.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span id="xdx_909_eus-gaap--InterestExpenseDebt_pp0p0_c20210701__20210930__us-gaap--DebtInstrumentAxis__custom--InitialHorizonCreditAgreementAmendmentMember_z5DQKDWBU018"&gt;No&lt;/span&gt;
interest expense was recognized during the three months ended September 31, 2021 as the amounts owed under the Horizon Credit agreement
were paid off in June 2021. During the nine-month period ended September 30, 2021, the Company incurred $&lt;span id="xdx_90C_eus-gaap--InterestExpenseDebt_pp0p0_c20210101__20210930__us-gaap--DebtInstrumentAxis__custom--InitialHorizonCreditAgreementAmendmentMember_zWrWUN1FpUD5"&gt;225,920&lt;/span&gt; in interest expense
and amortized $&lt;span id="xdx_908_eus-gaap--AmortizationOfFinancingCosts_pp0p0_c20210101__20210930__us-gaap--DebtInstrumentAxis__custom--InitialHorizonCreditAgreementAmendmentMember_zLcQNQ0Hfwrh" title="Amortization of Debt Issuance Costs"&gt;139,428&lt;/span&gt; as interest expense for debt discounts and end of term charges in connection with the Horizon Credit Agreement.
During the three-month period ended September 30, 2020, the Company incurred $&lt;span id="xdx_90C_eus-gaap--InterestExpenseDebt_pp0p0_c20200701__20200930__us-gaap--DebtInstrumentAxis__custom--InitialHorizonCreditAgreementAmendmentMember_zN6F52tkJ0sj"&gt;198,738&lt;/span&gt; in interest expense and amortized $&lt;span id="xdx_90F_eus-gaap--AmortizationOfFinancingCosts_pp0p0_c20200701__20200930__us-gaap--DebtInstrumentAxis__custom--InitialHorizonCreditAgreementAmendmentMember_zshlLlKYqoZi"&gt;251,993&lt;/span&gt; as interest
expense for debt discounts and end of term charges in connection with the Initial Horizon Credit Agreement and Amendment. During the
nine-month period ended September 30, 2020, the Company incurred $&lt;span id="xdx_906_eus-gaap--InterestExpenseDebt_pp0p0_c20200101__20200930__us-gaap--DebtInstrumentAxis__custom--InitialHorizonCreditAgreementAmendmentMember_zILUViykdpw5"&gt;685,913&lt;/span&gt; in interest expense and amortized $&lt;span id="xdx_90C_eus-gaap--AmortizationOfFinancingCosts_pp0p0_c20200101__20200930__us-gaap--DebtInstrumentAxis__custom--InitialHorizonCreditAgreementAmendmentMember_zp5b6h6NMljj"&gt;444,786&lt;/span&gt; as interest expense
for debt discounts and end of term charges in connection with the Initial Horizon Credit Agreement and Amendment.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p id="xdx_895_eus-gaap--ScheduleOfDebtTableTextBlock_zjC3nRh8HDck" style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;On
June 18, 2021, as a condition of entering into the SVB Loan Facility, the Company paid the outstanding principal balance, an early termination
fee and the end of term charges in full satisfaction of the Horizon Credit Agreement, as amended. Following is a schedule of the amounts
paid to Horizon on June 18, 2021.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;span id="xdx_8B4_zU7vNCMHFGEa" style="display: none"&gt;Schedule of Debt&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; margin-left: auto; border-collapse: collapse; width: 80%; margin-right: auto"&gt;
  &lt;tr style="display: none; vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_498_20210618_ztD4ky32hVBb" style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_40D_eus-gaap--LineOfCreditFacilityFairValueOfAmountOutstanding_iI_hdei--LegalEntityAxis__custom--HorizonTechnologyFinanceCorporationMember_maLOCzybh_zP6hb73XXgJa" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="width: 74%"&gt;Principal balance at June 18, 2021&lt;/td&gt;&lt;td style="width: 2%"&gt;&#160;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;$&lt;/td&gt;&lt;td style="width: 22%; text-align: right"&gt;5,000,000&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_407_ecustom--EarlyTerminationFee_iI_hdei--LegalEntityAxis__custom--HorizonTechnologyFinanceCorporationMember_maLOCzybh_zGvJVokrQ3Wi" style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left"&gt;Early termination fees&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;150,000&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_402_ecustom--EndOfTermCharges_iI_hdei--LegalEntityAxis__custom--HorizonTechnologyFinanceCorporationMember_maLOCzybh_zTZFg0s0ddWh" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left; padding-bottom: 1.5pt"&gt;End of term charges&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="border-bottom: Black 1.5pt solid; text-align: right"&gt;275,000&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_406_eus-gaap--LineOfCredit_iTI_hdei--LegalEntityAxis__custom--HorizonTechnologyFinanceCorporationMember_mtLOCzybh_zPoVLGsP7Ua8" style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="padding-left: 10pt; padding-bottom: 2.5pt"&gt;Total&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;$&lt;/td&gt;&lt;td style="border-bottom: Black 2.5pt double; text-align: right"&gt;5,425,000&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;

&lt;p id="xdx_8A3_zC2GNrM4hlDl" style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"/&gt;&lt;/p&gt;



&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;During
the nine months ended September 30, 2021, the Company recorded a loss of $&lt;span id="xdx_909_eus-gaap--GainLossOnContractTermination_pp0p0_c20210101__20210930__us-gaap--TypeOfArrangementAxis__custom--HorizonCreditAgreementMember_z0KC6pOIEK01" title="Gain (Loss) on Contract Termination"&gt;234,419&lt;/span&gt; on the termination of the Horizon Credit Agreement,
as amended, which represented the early termination fee and the end of term fees, net of previously amortized interest expense totaling
$&lt;span id="xdx_90C_eus-gaap--InterestExpenseDebt_pp0p0_c20210101__20210930__us-gaap--TypeOfArrangementAxis__custom--HorizonCreditAgreementMember_z1R973dM7NB4"&gt;190,581&lt;/span&gt; on the date of its payoff.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

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    <us-gaap:LineOfCreditFacilityMaximumBorrowingCapacity
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      unitRef="USD">10000000</us-gaap:LineOfCreditFacilityMaximumBorrowingCapacity>
    <us-gaap:ProceedsFromLinesOfCredit
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      decimals="-6"
      unitRef="USD">6000000</us-gaap:ProceedsFromLinesOfCredit>
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      decimals="-6"
      unitRef="USD">4000000</us-gaap:LineOfCreditFacilityRemainingBorrowingCapacity>
    <us-gaap:DebtInstrumentInterestRateStatedPercentage
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      decimals="INF"
      unitRef="Pure">0.0325</us-gaap:DebtInstrumentInterestRateStatedPercentage>
    <CLSN:FinalPaymentPercentage
      contextRef="AsOf2021-06-18_custom_SVBLoanFacilityMember"
      decimals="INF"
      unitRef="Pure">0.03</CLSN:FinalPaymentPercentage>
    <us-gaap:LineOfCredit
      contextRef="AsOf2021-06-18_custom_SVBLoanFacilityMember"
      decimals="-6"
      unitRef="USD">10000000</us-gaap:LineOfCredit>
    <us-gaap:DebtInstrumentDescription contextRef="From2021-06-012021-06-18_custom_SVBLoanFacilityMember">Payments under the loan agreement are
interest only for the first 24 months after loan closing, followed by a 24-month amortization period of principal and interest through
the scheduled maturity date.</us-gaap:DebtInstrumentDescription>
    <us-gaap:InterestAndDebtExpense
      contextRef="From2021-06-012021-06-18_custom_SVBLoanFacilityMember"
      decimals="0"
      unitRef="USD">243370</us-gaap:InterestAndDebtExpense>
    <CLSN:EndOfTermChargePercentage
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      decimals="INF"
      unitRef="Pure">0.030</CLSN:EndOfTermChargePercentage>
    <us-gaap:AmortizationOfFinancingCosts
      contextRef="From2021-06-012021-06-18_custom_SVBLoanFacilityMember"
      decimals="0"
      unitRef="USD">300000</us-gaap:AmortizationOfFinancingCosts>
    <us-gaap:InterestExpenseDebt
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      decimals="0"
      unitRef="USD">49883</us-gaap:InterestExpenseDebt>
    <us-gaap:InterestExpenseDebt
      contextRef="From2021-01-012021-09-30_custom_SVBLoanFacilityMember"
      decimals="0"
      unitRef="USD">56875</us-gaap:InterestExpenseDebt>
    <us-gaap:AmortizationOfFinancingCostsAndDiscounts
      contextRef="From2021-07-012021-09-30_custom_SVBLoanFacilityMember"
      decimals="0"
      unitRef="USD">45687</us-gaap:AmortizationOfFinancingCostsAndDiscounts>
    <us-gaap:AmortizationOfFinancingCostsAndDiscounts
      contextRef="From2021-01-012021-09-30_custom_SVBLoanFacilityMember"
      decimals="0"
      unitRef="USD">52144</us-gaap:AmortizationOfFinancingCostsAndDiscounts>
    <us-gaap:ScheduleOfMaturitiesOfLongTermDebtTableTextBlock contextRef="From2021-01-01to2021-09-30">&lt;p id="xdx_892_eus-gaap--ScheduleOfMaturitiesOfLongTermDebtTableTextBlock_zXtImcS3lVzd" style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Following
is a schedule of future principal payments, net of unamortized debt discounts and amortized end-of-term fee, due on the SVB Loan Facility:&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;span id="xdx_8B5_zKg8XUhRLq73" style="display: none"&gt;Schedule of Future Principle Payments, Net of Unamortized Debt Discounts&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; margin-left: auto; border-collapse: collapse; width: 80%; margin-right: auto"&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" id="xdx_496_20210930_zVIigqYXYyUh" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;As of &lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;September 30,&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_402_eus-gaap--LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths_iI_pp0p0_maDICAzbmk_zg2ckJTrSEBc" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left"&gt;2022&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;$&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl1133"&gt;&#x2013;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_406_eus-gaap--LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo_iI_pp0p0_maDICAzbmk_zZZhOad9o9Hk" style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="width: 74%; text-align: left"&gt;2023&lt;/td&gt;&lt;td style="width: 2%"&gt;&#160;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="width: 22%; text-align: right"&gt;750,000&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_409_eus-gaap--LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree_iI_pp0p0_maDICAzbmk_zLvwzQ02hapj" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left"&gt;2024&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;3,000,000&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_403_ecustom--LongTermDebtMaturitiesRepaymentsOfPrincipalYearFourAndThereAfter_iI_pp0p0_maDICAzbmk_zkQjMgBCaOD6" style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;2025 and thereafter&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="border-bottom: Black 1.5pt solid; text-align: right"&gt;2,250,000&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_406_eus-gaap--DebtInstrumentCarryingAmount_iTI_pp0p0_mtDICAzbmk_maLTDzyWo_zskOsYCmouo3" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Subtotal of future principal payments&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;6,000,000&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_401_eus-gaap--DeferredFinanceCostsNet_iNI_pp0p0_di_msLTDzyWo_z42UJjJJQXP1" style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Unamortized debt premium, net&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="border-bottom: Black 1.5pt solid; text-align: right"&gt;(191,226&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;)&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_404_eus-gaap--LongTermDebt_iTI_pp0p0_mtLTDzyWo_z4lvv0gQZC0k" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="padding-left: 10pt; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Total&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;$&lt;/td&gt;&lt;td style="border-bottom: Black 2.5pt double; text-align: right"&gt;5,808,774&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;

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    <us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo contextRef="AsOf2021-09-30" decimals="0" unitRef="USD">750000</us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo>
    <us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree contextRef="AsOf2021-09-30" decimals="0" unitRef="USD">3000000</us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree>
    <CLSN:LongTermDebtMaturitiesRepaymentsOfPrincipalYearFourAndThereAfter contextRef="AsOf2021-09-30" decimals="0" unitRef="USD">2250000</CLSN:LongTermDebtMaturitiesRepaymentsOfPrincipalYearFourAndThereAfter>
    <us-gaap:DebtInstrumentCarryingAmount contextRef="AsOf2021-09-30" decimals="0" unitRef="USD">6000000</us-gaap:DebtInstrumentCarryingAmount>
    <us-gaap:DeferredFinanceCostsNet contextRef="AsOf2021-09-30" decimals="0" unitRef="USD">191226</us-gaap:DeferredFinanceCostsNet>
    <us-gaap:LongTermDebt contextRef="AsOf2021-09-30" decimals="0" unitRef="USD">5808774</us-gaap:LongTermDebt>
    <us-gaap:LineOfCreditFacilityMaximumBorrowingCapacity
      contextRef="AsOf2018-06-27_custom_InitialHorizonCreditAgreementMember"
      decimals="-6"
      unitRef="USD">10000000</us-gaap:LineOfCreditFacilityMaximumBorrowingCapacity>
    <us-gaap:ProceedsFromLinesOfCredit
      contextRef="From2018-06-262018-06-27_custom_InitialHorizonCreditAgreementMember"
      decimals="-6"
      unitRef="USD">10000000</us-gaap:ProceedsFromLinesOfCredit>
    <us-gaap:LineOfCreditFacilityRemainingBorrowingCapacity
      contextRef="AsOf2018-06-27_custom_InitialHorizonCreditAgreementMember"
      decimals="-6"
      unitRef="USD">5000000</us-gaap:LineOfCreditFacilityRemainingBorrowingCapacity>
    <CLSN:PaymentOfDebtEndTermCharges
      contextRef="From2020-08-272020-08-28_custom_AmendmentToHorizonCreditAgreementMember_custom_HorizonTechnologyFinanceCorporationMember"
      decimals="-5"
      unitRef="USD">200000</CLSN:PaymentOfDebtEndTermCharges>
    <us-gaap:LineOfCreditFacilityRemainingBorrowingCapacity
      contextRef="AsOf2018-06-27_custom_InitialHorizonCreditAgreementMember"
      decimals="-6"
      unitRef="USD">5000000</us-gaap:LineOfCreditFacilityRemainingBorrowingCapacity>
    <us-gaap:DebtInstrumentFaceAmount
      contextRef="AsOf2020-08-28_custom_AmendmentToHorizonCreditAgreementMember_custom_HorizonTechnologyFinanceCorporationMember"
      decimals="-6"
      unitRef="USD">5000000</us-gaap:DebtInstrumentFaceAmount>
    <us-gaap:DebtInstrumentInterestRateTerms contextRef="From2020-08-272020-08-28_custom_AmendmentToHorizonCreditAgreementMember_custom_HorizonTechnologyFinanceCorporationMember">The obligations bore interest at a
rate calculated based an amount by which the one-month LIBOR exceeds 2% plus 7.625%. In no event shall the interest rate be less than
9.625%. Payments pursuant to the Amendment were interest only for the first twelve (12) months after August 1, 2020, followed by a 21-month
amortization period of principal and interest through the scheduled maturity date on April 1, 2023. In addition, the remaining $5 million
in obligations was subject to an end of term fee equal, in the aggregate, to $275,000, which amount was payable upon the maturity of
the obligations or upon the date of final payment or default, as applicable.</us-gaap:DebtInstrumentInterestRateTerms>
    <us-gaap:PaymentsOfDebtExtinguishmentCosts
      contextRef="From2020-08-272020-08-28_custom_AmendmentToHorizonCreditAgreementMember_custom_HorizonTechnologyFinanceCorporationMember"
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      unitRef="USD">5000000</us-gaap:PaymentsOfDebtExtinguishmentCosts>
    <us-gaap:DebtInstrumentFeeAmount
      contextRef="AsOf2020-08-28_custom_AmendmentToHorizonCreditAgreementMember_custom_HorizonTechnologyFinanceCorporationMember"
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      unitRef="USD">275000</us-gaap:DebtInstrumentFeeAmount>
    <us-gaap:DebtInstrumentRestrictiveCovenants contextRef="From2020-08-272020-08-28_custom_AmendmentToHorizonCreditAgreementMember_custom_HorizonTechnologyFinanceCorporationMember">In connection with the Amendment, Celsion agreed to a liquidity
covenant which provides that, at all times, Celsion shall maintain unrestricted cash and/or cash equivalents on deposit in accounts over
which the applicable Lenders maintain an account control agreement in an amount not less than $2.5 million. In addition, pursuant to
the Amendment, Celsion agreed to provide evidence to Horizon on or before March 31, 2021, that it received aggregate cash proceeds of
not less than $5 million from the sale of equity, debt, its New Jersey net operating losses, or a combination thereof, subsequent to
the date of the Amendment. The Company met this requirement during the fourth quarter of 2020.</us-gaap:DebtInstrumentRestrictiveCovenants>
    <us-gaap:InterestAndDebtExpense
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      decimals="0"
      unitRef="USD">175000</us-gaap:InterestAndDebtExpense>
    <us-gaap:LoanProcessingFee
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      decimals="0"
      unitRef="USD">100000</us-gaap:LoanProcessingFee>
    <us-gaap:DebtInstrumentUnamortizedDiscount
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      decimals="0"
      unitRef="USD">782116</us-gaap:DebtInstrumentUnamortizedDiscount>
    <CLSN:EndOfTermChargePercentage
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    <us-gaap:DeferredFinanceCostsNet
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      decimals="0"
      unitRef="USD">400000</us-gaap:DeferredFinanceCostsNet>
    <us-gaap:ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights
      contextRef="AsOf2018-06-27_custom_InitialHorizonCreditAgreementMember_us-gaap_CommonStockMember"
      decimals="INF"
      unitRef="Shares">190114</us-gaap:ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights>
    <us-gaap:ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1
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      unitRef="USDPShares">2.63</us-gaap:ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1>
    <us-gaap:FairValueAdjustmentOfWarrants
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      decimals="0"
      unitRef="USD">507116</us-gaap:FairValueAdjustmentOfWarrants>
    <us-gaap:ClassOfWarrantOrRightOutstanding
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      decimals="INF"
      unitRef="Shares">95057</us-gaap:ClassOfWarrantOrRightOutstanding>
    <us-gaap:ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1
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      unitRef="USDPShares">1.01</us-gaap:ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1>
    <us-gaap:ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights
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      unitRef="Shares">247525</us-gaap:ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights>
    <CLSN:ClassOfWarrantOrRightWarrantsOrRightsCancelled
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      unitRef="Shares">95057</CLSN:ClassOfWarrantOrRightWarrantsOrRightsCancelled>
    <us-gaap:PaymentsOfDebtExtinguishmentCosts
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      decimals="-6"
      unitRef="USD">5000000</us-gaap:PaymentsOfDebtExtinguishmentCosts>
    <us-gaap:DebtInstrumentUnamortizedDiscount
      contextRef="AsOf2020-08-28_custom_AmendmentToHorizonCreditAgreementMember_custom_HorizonTechnologyFinanceCorporationMember"
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      unitRef="USD">200000</us-gaap:DebtInstrumentUnamortizedDiscount>
    <us-gaap:DebtInstrumentFaceAmount
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      unitRef="USD">5000000</us-gaap:DebtInstrumentFaceAmount>
    <us-gaap:DeferredFinanceCostsNet
      contextRef="AsOf2020-08-28_custom_AmendmentToHorizonCreditAgreementMember_custom_HorizonTechnologyFinanceCorporationMember"
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      unitRef="USD">5000</us-gaap:DeferredFinanceCostsNet>
    <us-gaap:WarrantsNotSettleableInCashFairValueDisclosure
      contextRef="AsOf2020-08-28_custom_AmendmentToHorizonCreditAgreementMember_custom_HorizonTechnologyFinanceCorporationMember"
      decimals="0"
      unitRef="USD">247548</us-gaap:WarrantsNotSettleableInCashFairValueDisclosure>
    <us-gaap:DebtInstrumentUnamortizedDiscount
      contextRef="AsOf2021-06-30_custom_AmendmentToHorizonCreditAgreementMember_custom_HorizonTechnologyFinanceCorporationMember"
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      unitRef="USD">109706</us-gaap:DebtInstrumentUnamortizedDiscount>
    <CLSN:EndOfTermFees
      contextRef="From2018-06-262018-06-27_custom_InitialHorizonCreditAgreementMember"
      decimals="0"
      unitRef="USD">275000</CLSN:EndOfTermFees>
    <us-gaap:DebtInstrumentFeeAmount
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      decimals="0"
      unitRef="USD">142605</us-gaap:DebtInstrumentFeeAmount>
    <us-gaap:InterestExpenseDebt
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      decimals="0"
      unitRef="USD">225920</us-gaap:InterestExpenseDebt>
    <us-gaap:AmortizationOfFinancingCosts
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      decimals="0"
      unitRef="USD">139428</us-gaap:AmortizationOfFinancingCosts>
    <us-gaap:InterestExpenseDebt
      contextRef="From2020-07-012020-09-30_custom_InitialHorizonCreditAgreementAmendmentMember"
      decimals="0"
      unitRef="USD">198738</us-gaap:InterestExpenseDebt>
    <us-gaap:AmortizationOfFinancingCosts
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      decimals="0"
      unitRef="USD">251993</us-gaap:AmortizationOfFinancingCosts>
    <us-gaap:InterestExpenseDebt
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      decimals="0"
      unitRef="USD">685913</us-gaap:InterestExpenseDebt>
    <us-gaap:AmortizationOfFinancingCosts
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      decimals="0"
      unitRef="USD">444786</us-gaap:AmortizationOfFinancingCosts>
    <us-gaap:ScheduleOfDebtTableTextBlock contextRef="From2021-01-01to2021-09-30">&lt;p id="xdx_895_eus-gaap--ScheduleOfDebtTableTextBlock_zjC3nRh8HDck" style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;On
June 18, 2021, as a condition of entering into the SVB Loan Facility, the Company paid the outstanding principal balance, an early termination
fee and the end of term charges in full satisfaction of the Horizon Credit Agreement, as amended. Following is a schedule of the amounts
paid to Horizon on June 18, 2021.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;span id="xdx_8B4_zU7vNCMHFGEa" style="display: none"&gt;Schedule of Debt&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; margin-left: auto; border-collapse: collapse; width: 80%; margin-right: auto"&gt;
  &lt;tr style="display: none; vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_498_20210618_ztD4ky32hVBb" style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_40D_eus-gaap--LineOfCreditFacilityFairValueOfAmountOutstanding_iI_hdei--LegalEntityAxis__custom--HorizonTechnologyFinanceCorporationMember_maLOCzybh_zP6hb73XXgJa" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="width: 74%"&gt;Principal balance at June 18, 2021&lt;/td&gt;&lt;td style="width: 2%"&gt;&#160;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;$&lt;/td&gt;&lt;td style="width: 22%; text-align: right"&gt;5,000,000&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_407_ecustom--EarlyTerminationFee_iI_hdei--LegalEntityAxis__custom--HorizonTechnologyFinanceCorporationMember_maLOCzybh_zGvJVokrQ3Wi" style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left"&gt;Early termination fees&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;150,000&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_402_ecustom--EndOfTermCharges_iI_hdei--LegalEntityAxis__custom--HorizonTechnologyFinanceCorporationMember_maLOCzybh_zTZFg0s0ddWh" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left; padding-bottom: 1.5pt"&gt;End of term charges&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="border-bottom: Black 1.5pt solid; text-align: right"&gt;275,000&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_406_eus-gaap--LineOfCredit_iTI_hdei--LegalEntityAxis__custom--HorizonTechnologyFinanceCorporationMember_mtLOCzybh_zPoVLGsP7Ua8" style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="padding-left: 10pt; padding-bottom: 2.5pt"&gt;Total&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;$&lt;/td&gt;&lt;td style="border-bottom: Black 2.5pt double; text-align: right"&gt;5,425,000&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;

</us-gaap:ScheduleOfDebtTableTextBlock>
    <us-gaap:LineOfCreditFacilityFairValueOfAmountOutstanding
      contextRef="AsOf2021-06-18_custom_HorizonTechnologyFinanceCorporationMember"
      decimals="0"
      unitRef="USD">5000000</us-gaap:LineOfCreditFacilityFairValueOfAmountOutstanding>
    <CLSN:EarlyTerminationFee
      contextRef="AsOf2021-06-18_custom_HorizonTechnologyFinanceCorporationMember"
      decimals="0"
      unitRef="USD">150000</CLSN:EarlyTerminationFee>
    <CLSN:EndOfTermCharges
      contextRef="AsOf2021-06-18_custom_HorizonTechnologyFinanceCorporationMember"
      decimals="0"
      unitRef="USD">275000</CLSN:EndOfTermCharges>
    <us-gaap:LineOfCredit
      contextRef="AsOf2021-06-18_custom_HorizonTechnologyFinanceCorporationMember"
      decimals="0"
      unitRef="USD">5425000</us-gaap:LineOfCredit>
    <us-gaap:GainLossOnContractTermination
      contextRef="From2021-01-012021-09-30_custom_HorizonCreditAgreementMember"
      decimals="0"
      unitRef="USD">234419</us-gaap:GainLossOnContractTermination>
    <us-gaap:InterestExpenseDebt
      contextRef="From2021-01-012021-09-30_custom_HorizonCreditAgreementMember"
      decimals="0"
      unitRef="USD">190581</us-gaap:InterestExpenseDebt>
    <us-gaap:StockholdersEquityNoteDisclosureTextBlock contextRef="From2021-01-01to2021-09-30">&lt;p id="xdx_801_eus-gaap--StockholdersEquityNoteDisclosureTextBlock_zFiz0S8zUCwc" style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Note
12. &lt;span id="xdx_828_zei5yGTGZdw5"&gt;Stockholders&#x2019; Equity&lt;/span&gt;&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;In
September 2018, the Company filed with the SEC a $&lt;span id="xdx_90C_ecustom--ShelfRegistrationStatementAmount_pn6n6_c20180901__20180930_zDUcNwDgPqhh" title="Shelf registration statement amount"&gt;75&lt;/span&gt; million shelf registration statement on Form S-3 (the 2018 Shelf Registration Statement)
that allows the Company to issue any combination of common stock, preferred stock or warrants to purchase common stock or preferred stock.
This shelf registration was declared effective on October 12, 2018 and was fully utilized by the end of January 2021.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;On
March 19, 2021, the Company filed with the SEC a new $&lt;span id="xdx_90E_ecustom--ShelfRegistrationStatementAmount_pn6n6_c20210318__20210319_zH1DMe2iYPaf" title="Shelf registration statement amount"&gt;100&lt;/span&gt; million shelf registration statement on Form S-3 (the &#x201c;2021 Registration
Statement&#x201d;) that allows the Company to issue any combination of common stock, preferred stock or warrants to purchase common stock
or preferred stock. This shelf registration was declared effective on March 30, 2021.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;i&gt;&lt;span style="text-decoration: underline"&gt;Capital
on Demand&lt;sup&gt;TM&lt;/sup&gt; Sales Agreement&lt;/span&gt;&lt;/i&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;On
December 4, 2018, the Company entered into the Capital on Demand Agreement with JonesTrading, pursuant to which the Company may offer
and sell, from time to time, through JonesTrading shares of Common Stock having an aggregate offering price of up to $&lt;span id="xdx_903_ecustom--AggregateOfferingPrices_pn5n6_c20181202__20181204__us-gaap--TypeOfArrangementAxis__custom--CapitalOnDemandTMSalesAgreementMember_zfsqkotLDH99" title="Less than 12 months, unrealized gains, fair value"&gt;16.0&lt;/span&gt; million.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;During
2020 through September 30, 2020, the Company sold and issued an aggregate of &lt;span id="xdx_90B_eus-gaap--StockIssuedDuringPeriodSharesNewIssues_pn5n6_c20200101__20200930__us-gaap--TypeOfArrangementAxis__custom--CapitalOnDemandAgreementMember_z6A5y9peDF2e" title="Stock Issued During Period, Shares, New Issues"&gt;2.1&lt;/span&gt; million shares under the Capital on Demand Agreement,
receiving approximately $&lt;span id="xdx_90F_eus-gaap--ProceedsFromIssuanceOfCommonStock_c20200101__20200930__us-gaap--TypeOfArrangementAxis__custom--CapitalOnDemandAgreementMember_pn5n6" title="Proceeds from Issuance of Common Stock"&gt;4.3&lt;/span&gt; million in gross proceeds. During the first nine months of 2021, the Company sold &lt;span id="xdx_900_eus-gaap--StockIssuedDuringPeriodSharesNewIssues_pn5n6_c20210101__20210930__us-gaap--TypeOfArrangementAxis__custom--CapitalOnDemandAgreementMember_z2jZe1i04eQj" title="Stock Issued During Period, Shares, New Issues"&gt;7.2&lt;/span&gt; million shares under
the Capital on Demand Agreement, receiving approximately $&lt;span id="xdx_90E_eus-gaap--ProceedsFromIssuanceOfCommonStock_pn5n6_c20210101__20210930__us-gaap--TypeOfArrangementAxis__custom--CapitalOnDemandAgreementMember_zgHI5gh7TEF8" title="Proceeds from Issuance of Common Stock"&gt;6.9&lt;/span&gt; million in gross proceeds under the Capital on Demand Agreement.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;i&gt;&lt;span style="text-decoration: underline"&gt;Registered
Direct Offering&lt;/span&gt;&lt;/i&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;On
February 27, 2020, we entered into a Securities Purchase Agreement (the &#x201c;February 2020 Purchase Agreement&#x201d;) with several
institutional investors, pursuant to which we agreed to issue and sell, in a registered direct offering (the &#x201c;February 2020 Offering&#x201d;),
an aggregate of &lt;span id="xdx_905_eus-gaap--StockIssuedDuringPeriodSharesNewIssues_pp0p0_c20200226__20200227__us-gaap--TypeOfArrangementAxis__custom--SecuritiesPurchaseAgreementMember_zQ4IX1OdB1tg" title="Stock Issued During Period, Shares, New Issues"&gt;4,571,428&lt;/span&gt; shares of our common stock at an offering price of $&lt;span id="xdx_905_eus-gaap--SharesIssuedPricePerShare_c20200227__us-gaap--TypeOfArrangementAxis__custom--SecuritiesPurchaseAgreementMember_pdd" title="Shares Issued, Price Per Share"&gt;1.05&lt;/span&gt; per Share for gross proceeds of approximately $&lt;span id="xdx_901_eus-gaap--ProceedsFromIssuanceOfCommonStock_c20200226__20200227__us-gaap--TypeOfArrangementAxis__custom--SecuritiesPurchaseAgreementMember_pn5n6" title="Proceeds from Issuance of Common Stock"&gt;4.8&lt;/span&gt;
million before the deduction of the Placement Agent fees and offering expenses. In a concurrent private placement (the &#x201c;Private
Placement&#x201d;), the Company issued to the investors that participated in the February 2020 Offering, for no additional consideration,
warrants to purchase up to &lt;span id="xdx_90C_eus-gaap--ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachWarrantOrRight_c20200227__us-gaap--TypeOfArrangementAxis__custom--SecuritiesPurchaseAgreementMember__us-gaap--StatementEquityComponentsAxis__custom--OriginalWarrantsMember_pdd" title="Class of Warrant or Right, Number of Securities Called by Each Warrant or Right"&gt;2,971,428&lt;/span&gt; shares of common stock (the &#x201c;Original Warrants&#x201d;). The Original Warrants were initially
exercisable six months following their date of issue and were set to expire on the &lt;span id="xdx_90E_eus-gaap--WarrantsAndRightsOutstandingTerm_iI_dxL_c20200227__us-gaap--TypeOfArrangementAxis__custom--SecuritiesPurchaseAgreementMember__us-gaap--StatementEquityComponentsAxis__custom--OriginalWarrantsMember_zFfbHqMhzLd2" title="Warrants and Rights Outstanding, Term::XDX::P5Y"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl1242"&gt;five&lt;/span&gt;&lt;/span&gt;-year anniversary of such initial exercise date.
The Original Warrants had an exercise price of $&lt;span id="xdx_90D_eus-gaap--ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1_c20200227__us-gaap--TypeOfArrangementAxis__custom--SecuritiesPurchaseAgreementMember__us-gaap--StatementEquityComponentsAxis__custom--OriginalWarrantsMember_pdd" title="Class of Warrant or Right, Exercise Price of Warrants or Rights"&gt;1.15&lt;/span&gt; per share subject to adjustment as provided therein. On March 12, 2020, the Company
entered into private exchange agreements (the &#x201c;Exchange Agreements&#x201d;) with holders of the Original Warrants. Pursuant to the
Exchange Agreements, in return for a higher exercise price of $&lt;span id="xdx_90D_eus-gaap--ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1_c20200312__us-gaap--TypeOfArrangementAxis__custom--ExchangeAgreementsMember__us-gaap--StatementEquityComponentsAxis__us-gaap--WarrantMember_pdd" title="Class of Warrant or Right, Exercise Price of Warrants or Rights"&gt;1.24&lt;/span&gt; per share of common stock, the Company issued new warrants to the
Investors to purchase up to &lt;span id="xdx_906_eus-gaap--ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachWarrantOrRight_iI_pp0p0_c20200312__us-gaap--TypeOfArrangementAxis__custom--ExchangeAgreementsMember__us-gaap--StatementEquityComponentsAxis__us-gaap--WarrantMember_zO8kgzLMskCj" title="Class of Warrant or Right, Number of Securities Called by Each Warrant or Right"&gt;3,200,000&lt;/span&gt; shares of common stock (the &#x201c;Exchange Warrants&#x201d;) in exchange for the Original Warrants.
The Exchange Warrants, like the Original Warrants, are initially exercisable six months following their issuance (the &#x201c;Initial
Exercise Date&#x201d;) and expire on the &lt;span id="xdx_902_eus-gaap--WarrantsAndRightsOutstandingTerm_iI_dxL_c20200312__us-gaap--TypeOfArrangementAxis__custom--ExchangeAgreementsMember__us-gaap--StatementEquityComponentsAxis__us-gaap--WarrantMember_zwynHVE8wiVj" title="Warrants and Rights Outstanding, Term::XDX::P5Y"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl1250"&gt;five&lt;/span&gt;&lt;/span&gt;-year anniversary of their Initial Exercise Date. Other than having a higher exercise price,
different issue date, Initial Exercise Date and expiration date, the terms of the Exchange Warrants are identical to those of the Original
Warrants. On July 31, 2020, the Company filed a Form S-3 Registration Statement to register the shares of common stock issuable under
the Exchange Warrants; the Registration Statement was declared effective by the SEC on August 13, 2020. No Exchange Warrants were exercised
during 2020. During 2021 through the date of this Quarterly Report on Form 10-Q, the Company issued &lt;span id="xdx_900_eus-gaap--ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachWarrantOrRight_iI_pn5n6_c20210930__us-gaap--TypeOfArrangementAxis__custom--ExchangeAgreementsMember_zaYg4CevQWng" title="Class of Warrant or Right, Number of Securities Called by Each Warrant or Right"&gt;1.2&lt;/span&gt; million shares pursuant to investors
exercising Exchange Warrants, receiving approximately $&lt;span id="xdx_908_eus-gaap--ProceedsFromIssuanceOfWarrants_c20210101__20210930__us-gaap--TypeOfArrangementAxis__custom--ExchangeAgreementsMember_pn5n6" title="Proceeds from Issuance of Warrants"&gt;1.5&lt;/span&gt; million in net proceeds.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;i&gt;&lt;span style="text-decoration: underline"&gt;Underwritten
Offering&lt;/span&gt;&lt;/i&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;On
June 22, 2020, the Company entered into an underwriting agreement (the &#x201c;Underwriting Agreement&#x201d;) with Oppenheimer &amp;amp; Co.
Inc. (the &#x201c;Underwriter&#x201d;), relating to the issuance and sale (the &#x201c;Underwritten Offering&#x201d;) of &lt;span id="xdx_90A_eus-gaap--StockIssuedDuringPeriodSharesNewIssues_pp0p0_c20200621__20200622__us-gaap--TypeOfArrangementAxis__custom--UnderwritingAgreementMember__us-gaap--SubsidiarySaleOfStockAxis__custom--UnderwrittenOfferingMember_zDJyrkNMe5E8" title="Stock Issued During Period, Shares, New Issues"&gt;2,666,667&lt;/span&gt; shares
of the Company&#x2019;s common stock. Pursuant to the terms of the Underwriting Agreement, the Underwriter agreed to purchase the shares
at a price of $&lt;span id="xdx_903_eus-gaap--SharePrice_c20200622__us-gaap--TypeOfArrangementAxis__custom--UnderwritingAgreementMember__us-gaap--SubsidiarySaleOfStockAxis__custom--UnderwrittenOfferingMember_pdd" title="Share Price"&gt;3.4875&lt;/span&gt; per share. The Underwriter offered the shares at a public offering price of $&lt;span id="xdx_907_eus-gaap--SharesIssuedPricePerShare_c20200622__us-gaap--TypeOfArrangementAxis__custom--UnderwritingAgreementMember__us-gaap--SubsidiarySaleOfStockAxis__custom--UnderwrittenOfferingMember_pdd" title="Shares Issued, Price Per Share"&gt;3.75&lt;/span&gt; per share, reflecting an underwriting
discount equal to $&lt;span id="xdx_909_ecustom--UnderwritingDiscountPricePerShare_c20200621__20200622__us-gaap--TypeOfArrangementAxis__custom--UnderwritingAgreementMember__us-gaap--SubsidiarySaleOfStockAxis__custom--UnderwrittenOfferingMember_pdd" title="[custom:UnderwritingDiscountPricePerShare]"&gt;0.2625&lt;/span&gt;, or &lt;span id="xdx_90A_ecustom--PercentageOfUnderwritingDiscountOnPublicOfferingPrice_pid_dp_uPure_c20200621__20200622__us-gaap--TypeOfArrangementAxis__custom--UnderwritingAgreementMember__us-gaap--SubsidiarySaleOfStockAxis__custom--UnderwrittenOfferingMember_zirax2m5ndE7" title="Payments from sale of nols"&gt;7.0&lt;/span&gt;% of the public offering price. The net proceeds to the Company from the Underwritten Offering, after
deducting the underwriting discount and estimated offering expenses payable by the Company, were approximately $&lt;span id="xdx_902_eus-gaap--ProceedsFromIssuanceOfCommonStock_c20200621__20200622__us-gaap--TypeOfArrangementAxis__custom--UnderwritingAgreementMember__us-gaap--SubsidiarySaleOfStockAxis__custom--UnderwrittenOfferingMember_pn5n6" title="Proceeds from Issuance of Common Stock"&gt;9.1&lt;/span&gt; million.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;




&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"/&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Pursuant
to the Underwriting Agreement, until December 31, 2020, the Underwriter had a right of first refusal to act as sole underwriter, initial
purchaser, placement/selling agent, or arranger, as the case may be, on any new financing for the Company (excluding equipment lease
financings, loans or grants from governmental authorities or in connection with government programs and financings relating to or sales
of tax attributes) during such period. The Underwriter had the sole right to determine whether or not any other broker dealer could participate
in any such offering and the economic terms of any such participation.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;i&gt;&lt;span style="text-decoration: underline"&gt;January
2021 Registered Direct Offering&lt;/span&gt;&lt;/i&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;On
January 22, 2021, the Company entered into a Securities Purchase Agreement (the &#x201c;January 2021 Purchase Agreement&#x201d;) with several
institutional investors, pursuant to which the Company agreed to issue and sell, in a registered direct offering (the &#x201c;January
2021 Offering&#x201d;), an aggregate of &lt;span id="xdx_901_eus-gaap--StockIssuedDuringPeriodSharesNewIssues_pp0p0_c20210121__20210122__us-gaap--TypeOfArrangementAxis__custom--UnderwritingAgreementMember__us-gaap--SubsidiarySaleOfStockAxis__custom--JanuaryRegisteredDirectOfferingMember_zCPJdA23FDdi" title="Stock Issued During Period, Shares, New Issues"&gt;25,925,925&lt;/span&gt; shares of the Company&#x2019;s common stock at an offering price of $&lt;span id="xdx_904_eus-gaap--SharePrice_iI_c20210122__us-gaap--TypeOfArrangementAxis__custom--UnderwritingAgreementMember__us-gaap--SubsidiarySaleOfStockAxis__custom--JanuaryRegisteredDirectOfferingMember_zHCgOo2Lk3Bb" title="Share Price"&gt;1.35&lt;/span&gt; per share
for gross proceeds of approximately $&lt;span id="xdx_904_eus-gaap--ProceedsFromIssuanceOfCommonStock_c20210121__20210122__us-gaap--TypeOfArrangementAxis__custom--UnderwritingAgreementMember__us-gaap--SubsidiarySaleOfStockAxis__custom--JanuaryRegisteredDirectOfferingMember_pn6n6" title="Proceeds from Issuance of Common Stock"&gt;35&lt;/span&gt; million before the deduction of the January 2021 Placement Agents (as defined below) fee and
offering expenses. The January 2021 Purchase Agreement contains customary representations, warranties and agreements by the Company and
customary conditions to closing. The closing of the January 2021 Offering occurred on January 26, 2021.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span id="xdx_907_ecustom--PlacementAgentFeeDescription_c20210121__20210122__us-gaap--TypeOfArrangementAxis__custom--UnderwritingAgreementMember__us-gaap--SubsidiarySaleOfStockAxis__custom--JanuaryRegisteredDirectOfferingMember" title="Placement agent fee description."&gt;In
connection with the January 2021 Offering, the Company entered into a placement agent agreement (the &#x201c;January 2021 Placement Agent
Agreement&#x201d;) with A.G.P./Alliance Global Partners (together with Brookline Capital Markets, the &#x201c;January 2021 Placement Agents&#x201d;)
pursuant to which the Company agreed to pay the January 2021 Placement Agents a cash fee equal to 7% of the aggregate gross proceeds
raised from the sale of the securities sold in the January 2021 Offering and reimburse the January 2021 Placement Agents for certain
of their expenses in an amount not to exceed $82,500.&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;i&gt;&lt;span style="text-decoration: underline"&gt;March
2021 Registered Direct Offering&lt;/span&gt;&lt;/i&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;On
March 31, 2021, the Company entered into a Securities Purchase Agreement (the &#x201c;March 2021 Purchase Agreement&#x201d;) with several
institutional investors, pursuant to which the Company agreed to issue and sell, in a registered direct offering (the &#x201c;March 2021
Offering&#x201d;), an aggregate of &lt;span id="xdx_903_eus-gaap--StockIssuedDuringPeriodSharesNewIssues_c20210301__20210331__us-gaap--TypeOfArrangementAxis__custom--UnderwritingAgreementMember__us-gaap--SubsidiarySaleOfStockAxis__custom--MarchRegisteredDirectOfferingMember_pdd" title="Stock Issued During Period, Shares, New Issues"&gt;11,538,462&lt;/span&gt; shares of the Company&#x2019;s common stock, at an offering price of $&lt;span id="xdx_90D_eus-gaap--SharePrice_c20210630__us-gaap--TypeOfArrangementAxis__custom--UnderwritingAgreementMember__us-gaap--SubsidiarySaleOfStockAxis__custom--MarchRegisteredDirectOfferingMember_pdd" title="Share Price"&gt;1.30&lt;/span&gt; per share for
gross proceeds of approximately $&lt;span id="xdx_90F_eus-gaap--ProceedsFromIssuanceOfCommonStock_c20210301__20210331__us-gaap--TypeOfArrangementAxis__custom--UnderwritingAgreementMember__us-gaap--SubsidiarySaleOfStockAxis__custom--MarchRegisteredDirectOfferingMember_pn6n6" title="Proceeds from Issuance of Common Stock"&gt;15&lt;/span&gt; million before the deduction of the placement agents fee and offering expenses. The shares were offered
by the Company pursuant to the 2021 Registration Statement. The closing of the Offering occurred on April 5, 2021.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span id="xdx_902_ecustom--PlacementAgentFeeDescription_c20210301__20210331__us-gaap--TypeOfArrangementAxis__custom--UnderwritingAgreementMember__us-gaap--SubsidiarySaleOfStockAxis__custom--MarchRegisteredDirectOfferingMember" title="Placement agent fee description."&gt;In
connection with the March 2021 Offering, the Company entered into a placement agent agreement (the &#x201c;March 2021 Placement Agent
Agreement&#x201d;) with A.G.P./Alliance Global Partners, as lead placement agent (&#x201c;AGP,&#x201d; and together with JonesTrading Institutional
Services LLC and Brookline Capital Markets, a division of Arcadia Securities, LLC, serving as co-placement agents, the &#x201c;March 2021
Placement Agents&#x201d;), pursuant to which the Company agreed to pay the March 2021 Placement Agents an aggregate cash fee equal to
7% of the aggregate gross proceeds raised from the sale of the securities sold in the Offering and reimburse the Placement Agents for
certain of their expenses in an amount not to exceed $82,500.&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Under
the March 2021 Purchase Agreement and March 2021 Placement Agent Agreement, the Company and its subsidiaries were prohibited, for a period
of 90 days after the closing, from entering into any agreement to issue or announcing any issuance or proposed issuance of common stock
or any other securities that are at any time convertible into, or exercisable or exchangeable for, or otherwise entitle the holder thereof
to receive common stock without the prior written consent of AGP or the investors participating in the offering. For purposes of this
offering, AGP and the investors from the Company&#x2019;s January 2021 Offering waived a similar 90-day restriction in the placement agent
agreement and purchase agreement for that transaction.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;i&gt;&lt;span style="text-decoration: underline"&gt;LPC
Purchase Agreement&lt;/span&gt;&lt;/i&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;On
September 8, 2020, the Company entered into a purchase agreement (the &#x201c;LPC Purchase Agreement&#x201d;) and a Registration Rights
Agreement (the &#x201c;Registration Rights Agreement&#x201d;) with Lincoln Park Capital Fund, LLC (&#x201c;Lincoln Park&#x201d;), pursuant
to which, upon the terms and subject to the conditions and limitations set forth therein, the Company has the right to sell to Lincoln
Park up to $&lt;span id="xdx_90E_eus-gaap--StockIssuedDuringPeriodSharesNewIssues_pn5n6_c20200907__20200908__us-gaap--TypeOfArrangementAxis__custom--LPCPurchaseAgreementMember__dei--LegalEntityAxis__custom--LincolnParkCapitalFundLLCMember_zfddQJNXp0t6" title="Stock Issued During Period, Shares, New Issues"&gt;26.0&lt;/span&gt; million of shares of the Company&#x2019;s common stock at the Company&#x2019;s discretion as described below (the &#x201c;LPC
Offering&#x201d;). During 2020, the Company sold and issued an aggregate of &lt;span id="xdx_909_eus-gaap--StockIssuedDuringPeriodSharesNewIssues_pn5n6_c20200101__20201231__us-gaap--TypeOfArrangementAxis__custom--LPCPurchaseAgreementMember__dei--LegalEntityAxis__custom--LincolnParkCapitalFundLLCMember_zqN8pJDaNt96" title="Stock Issued During Period, Shares, New Issues"&gt;3.3&lt;/span&gt; million shares, including the &lt;span id="xdx_90E_eus-gaap--StockIssuedDuringPeriodSharesNewIssues_pp0p0_c20200907__20200908__us-gaap--TypeOfArrangementAxis__custom--LPCPurchaseAgreementMember__dei--LegalEntityAxis__custom--LincolnParkCapitalFundLLCMember__us-gaap--StatementEquityComponentsAxis__custom--LPCCommitmentSharesMember_zTm1sdwIaGhi" title="Stock Issued During Period, Shares, New Issues"&gt;437,828&lt;/span&gt; commitment shares,
under the LPC Purchase Agreement, receiving approximately $&lt;span id="xdx_90C_eus-gaap--ProceedsFromIssuanceOfCommonStock_pn5n6_c20200101__20201231__us-gaap--TypeOfArrangementAxis__custom--LPCPurchaseAgreementMember__dei--LegalEntityAxis__custom--LincolnParkCapitalFundLLCMember_zmgTqR18pFPi" title="Proceeds from Issuance of Common Stock"&gt;2.2&lt;/span&gt; million in gross proceeds. On January 21, 2021, the Company terminated
the LPC Purchase Agreement. The Company did not sell any shares under the LPC Purchase Agreement in 2021.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;




&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;&#160;&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;

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      contextRef="From2021-03-182021-03-19"
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      contextRef="From2018-12-022018-12-04_custom_CapitalOnDemandTMSalesAgreementMember"
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      contextRef="From2020-01-012020-09-30_custom_CapitalOnDemandAgreementMember"
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      decimals="-5"
      unitRef="USD">6900000</us-gaap:ProceedsFromIssuanceOfCommonStock>
    <us-gaap:StockIssuedDuringPeriodSharesNewIssues
      contextRef="From2020-02-262020-02-27_custom_SecuritiesPurchaseAgreementMember"
      decimals="0"
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      contextRef="AsOf2020-02-27_custom_SecuritiesPurchaseAgreementMember"
      decimals="INF"
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    <us-gaap:ProceedsFromIssuanceOfCommonStock
      contextRef="From2020-02-262020-02-27_custom_SecuritiesPurchaseAgreementMember"
      decimals="-5"
      unitRef="USD">4800000</us-gaap:ProceedsFromIssuanceOfCommonStock>
    <us-gaap:ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachWarrantOrRight
      contextRef="AsOf2020-02-27_custom_SecuritiesPurchaseAgreementMember_custom_OriginalWarrantsMember"
      decimals="INF"
      unitRef="Shares">2971428</us-gaap:ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachWarrantOrRight>
    <us-gaap:ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1
      contextRef="AsOf2020-02-27_custom_SecuritiesPurchaseAgreementMember_custom_OriginalWarrantsMember"
      decimals="INF"
      unitRef="USDPShares">1.15</us-gaap:ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1>
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      contextRef="AsOf2020-03-12_custom_ExchangeAgreementsMember_us-gaap_WarrantMember"
      decimals="INF"
      unitRef="USDPShares">1.24</us-gaap:ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1>
    <us-gaap:ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachWarrantOrRight
      contextRef="AsOf2020-03-12_custom_ExchangeAgreementsMember_us-gaap_WarrantMember"
      decimals="0"
      unitRef="Shares">3200000</us-gaap:ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachWarrantOrRight>
    <us-gaap:ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachWarrantOrRight
      contextRef="AsOf2021-09-30_custom_ExchangeAgreementsMember"
      decimals="-5"
      unitRef="Shares">1200000</us-gaap:ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachWarrantOrRight>
    <us-gaap:ProceedsFromIssuanceOfWarrants
      contextRef="From2021-01-012021-09-30_custom_ExchangeAgreementsMember"
      decimals="-5"
      unitRef="USD">1500000</us-gaap:ProceedsFromIssuanceOfWarrants>
    <us-gaap:StockIssuedDuringPeriodSharesNewIssues
      contextRef="From2020-06-212020-06-22_custom_UnderwritingAgreementMember_custom_UnderwrittenOfferingMember"
      decimals="0"
      unitRef="Shares">2666667</us-gaap:StockIssuedDuringPeriodSharesNewIssues>
    <us-gaap:SharePrice
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      decimals="INF"
      unitRef="USDPShares">3.4875</us-gaap:SharePrice>
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      contextRef="AsOf2020-06-22_custom_UnderwritingAgreementMember_custom_UnderwrittenOfferingMember"
      decimals="INF"
      unitRef="USDPShares">3.75</us-gaap:SharesIssuedPricePerShare>
    <CLSN:UnderwritingDiscountPricePerShare
      contextRef="From2020-06-212020-06-22_custom_UnderwritingAgreementMember_custom_UnderwrittenOfferingMember"
      decimals="INF"
      unitRef="USDPShares">0.2625</CLSN:UnderwritingDiscountPricePerShare>
    <CLSN:PercentageOfUnderwritingDiscountOnPublicOfferingPrice
      contextRef="From2020-06-212020-06-22_custom_UnderwritingAgreementMember_custom_UnderwrittenOfferingMember"
      decimals="INF"
      unitRef="Pure">0.070</CLSN:PercentageOfUnderwritingDiscountOnPublicOfferingPrice>
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      contextRef="From2020-06-212020-06-22_custom_UnderwritingAgreementMember_custom_UnderwrittenOfferingMember"
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    <us-gaap:StockIssuedDuringPeriodSharesNewIssues
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      decimals="INF"
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    <CLSN:PlacementAgentFeeDescription contextRef="From2021-01-212021-01-22_custom_UnderwritingAgreementMember_custom_JanuaryRegisteredDirectOfferingMember">In
connection with the January 2021 Offering, the Company entered into a placement agent agreement (the &#x201c;January 2021 Placement Agent
Agreement&#x201d;) with A.G.P./Alliance Global Partners (together with Brookline Capital Markets, the &#x201c;January 2021 Placement Agents&#x201d;)
pursuant to which the Company agreed to pay the January 2021 Placement Agents a cash fee equal to 7% of the aggregate gross proceeds
raised from the sale of the securities sold in the January 2021 Offering and reimburse the January 2021 Placement Agents for certain
of their expenses in an amount not to exceed $82,500.</CLSN:PlacementAgentFeeDescription>
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      contextRef="From2021-03-012021-03-31_custom_UnderwritingAgreementMember_custom_MarchRegisteredDirectOfferingMember"
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      unitRef="USD">15000000</us-gaap:ProceedsFromIssuanceOfCommonStock>
    <CLSN:PlacementAgentFeeDescription contextRef="From2021-03-012021-03-31_custom_UnderwritingAgreementMember_custom_MarchRegisteredDirectOfferingMember">In
connection with the March 2021 Offering, the Company entered into a placement agent agreement (the &#x201c;March 2021 Placement Agent
Agreement&#x201d;) with A.G.P./Alliance Global Partners, as lead placement agent (&#x201c;AGP,&#x201d; and together with JonesTrading Institutional
Services LLC and Brookline Capital Markets, a division of Arcadia Securities, LLC, serving as co-placement agents, the &#x201c;March 2021
Placement Agents&#x201d;), pursuant to which the Company agreed to pay the March 2021 Placement Agents an aggregate cash fee equal to
7% of the aggregate gross proceeds raised from the sale of the securities sold in the Offering and reimburse the Placement Agents for
certain of their expenses in an amount not to exceed $82,500.</CLSN:PlacementAgentFeeDescription>
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    <us-gaap:StockIssuedDuringPeriodSharesNewIssues
      contextRef="From2020-09-072020-09-08_custom_LPCPurchaseAgreementMember_custom_LincolnParkCapitalFundLLCMember_custom_LPCCommitmentSharesMember"
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    <us-gaap:ProceedsFromIssuanceOfCommonStock
      contextRef="From2020-01-012020-12-31_custom_LPCPurchaseAgreementMember_custom_LincolnParkCapitalFundLLCMember"
      decimals="-5"
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    <us-gaap:DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock contextRef="From2021-01-01to2021-09-30">&lt;p id="xdx_80D_eus-gaap--DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock_zLYZHq6yBjXd" style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Note
13. &lt;span id="xdx_82C_zlWAB2pTDeJ4"&gt;Stock-Based Compensation&lt;/span&gt;&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;The
Company has long-term compensation plans that permit the granting of equity-based awards in the form of stock options, restricted stock,
restricted stock units, stock appreciation rights, other stock awards, and performance awards.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;At
the 2018 Annual Stockholders Meeting of the Company held on May 15, 2018, stockholders approved the Celsion Corporation 2018 Stock Incentive
Plan (the &#x201c;2018 Plan&#x201d;). The 2018 Plan, as adopted, permits the granting of &lt;span id="xdx_907_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized_c20210930__us-gaap--PlanNameAxis__custom--TwoThousandAndEighteenStockIncentivePlanMember_pdd" title="Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized"&gt;2,700,000&lt;/span&gt; shares of Celsion common stock as equity
awards in the form of incentive stock options, nonqualified stock options, restricted stock, restricted stock units, stock appreciation
rights, other stock awards, performance awards, or in any combination of the foregoing. At the 2019 Annual Stockholders Meeting of the
Company held on May 14, 2019, stockholders approved an amendment to the 2018 Plan whereby the Company increased the number of common
stock shares available by &lt;span id="xdx_90B_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_c20190514__us-gaap--PlanNameAxis__custom--TwoThousandAndEighteenStockIncentivePlanMember__srt--RangeAxis__srt--MinimumMember_pdd" title="Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant"&gt;1,200,000&lt;/span&gt; to a total of &lt;span id="xdx_905_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_c20190514__us-gaap--PlanNameAxis__custom--TwoThousandAndEighteenStockIncentivePlanMember__srt--RangeAxis__srt--MaximumMember_pdd" title="Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant"&gt;3,900,000&lt;/span&gt; under the 2018 Plan, as amended. Prior to the adoption of the 2018 Plan,
the Company had maintained the Celsion Corporation 2007 Stock Incentive Plan (the &#x201c;2007 Plan&#x201d;). At the 2020 Annual Stockholders
Meeting of the Company held on June 15, 2020, stockholders approved an amendment to the 2018 Plan, as previously amended, whereby the
Company increased the number of shares of common stock available by &lt;span id="xdx_90D_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_c20200615__us-gaap--PlanNameAxis__custom--TwoThousandAndEighteenStockIncentivePlanMember__srt--RangeAxis__srt--MinimumMember_pdd" title="Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant"&gt;2,500,000&lt;/span&gt; to a total of &lt;span id="xdx_90F_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_c20200615__us-gaap--PlanNameAxis__custom--TwoThousandAndEighteenStockIncentivePlanMember__srt--RangeAxis__srt--MaximumMember_pdd" title="Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant"&gt;6,400,000&lt;/span&gt; under the 2018 Plan, as amended.
At the 2021 Annual Stockholders Meeting of the Company held on June 10, 2020, stockholders approved an amendment to the 2018 Plan, as
previously amended, whereby the Company increased the number of shares of common stock available by &lt;span id="xdx_90F_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_c20210610__us-gaap--PlanNameAxis__custom--TwoThousandAndEighteenStockIncentivePlanMember__srt--RangeAxis__srt--MinimumMember_pdd" title="Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant"&gt;7,700,000&lt;/span&gt; to a total of &lt;span id="xdx_90D_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_c20210610__us-gaap--PlanNameAxis__custom--TwoThousandAndEighteenStockIncentivePlanMember__srt--RangeAxis__srt--MaximumMember_pdd" title="Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant"&gt;14,100,000&lt;/span&gt;
under the 2018 Plan, as amended.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;The
Company has issued stock awards to employees and directors in the form of stock options and restricted stock. &lt;span id="xdx_902_ecustom--StockOptionsStrikePriceDescription_c20210101__20210930__us-gaap--PlanNameAxis__custom--TwoThousandSevenStockIncentivePlanMember" title="Stock options, strike price description"&gt;Options are generally granted
with strike prices equal to the fair market value of a share of Celsion common stock on the date of grant. Incentive stock options may
be granted to purchase shares of common stock at a price not less than 100% of the fair market value of the underlying shares on the
date of grant, provided that the exercise price of any incentive stock option granted to an eligible employee owning more than 10% of
the outstanding stock of Celsion must be at least 110% of such fair market value on the date of grant. Only officers and key employees
may receive incentive stock options.&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Option
and restricted stock awards vest upon terms determined by the Compensation Committee of the Board of Directors and are subject to accelerated
vesting in the event of a change of control or certain terminations of employment. The Company issues new shares to satisfy its obligations
from the exercise of options or the grant of restricted stock awards.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;On
September 28, 2018, and again on February 19, 2019, the Compensation Committee of the Board of Directors approved the grant of (i) inducement
stock options (the &#x201c;Inducement Option Grants&#x201d;) to purchase a total of &lt;span id="xdx_90C_eus-gaap--SharesIssued_c20180928__us-gaap--PlanNameAxis__custom--InducementOptionGrantsMember__srt--TitleOfIndividualAxis__custom--FiveNewEmployeesMember__us-gaap--StatementEquityComponentsAxis__us-gaap--CommonStockMember_pdd" title="Shares, Issued"&gt;164,004&lt;/span&gt; and &lt;span id="xdx_907_eus-gaap--SharesIssued_c20190219__us-gaap--PlanNameAxis__custom--InducementOptionGrantsMember__srt--TitleOfIndividualAxis__custom--FiveNewEmployeesMember__us-gaap--StatementEquityComponentsAxis__us-gaap--CommonStockMember_pdd" title="Shares, Issued"&gt;140,004&lt;/span&gt; shares of Celsion common stock,
respectively, and (ii) inducement restricted stock awards (the &#x201c;Inducement Stock Grants&#x201d;) totaling &lt;span id="xdx_90D_eus-gaap--SharesIssued_c20180928__us-gaap--PlanNameAxis__custom--InducementOptionGrantsMember__srt--TitleOfIndividualAxis__custom--FiveNewEmployeesMember__us-gaap--AwardTypeAxis__us-gaap--RestrictedStockMember_pdd" title="Shares, Issued"&gt;19,000&lt;/span&gt; and &lt;span id="xdx_906_eus-gaap--SharesIssued_c20190219__us-gaap--PlanNameAxis__custom--InducementOptionGrantsMember__srt--TitleOfIndividualAxis__custom--FiveNewEmployeesMember__us-gaap--AwardTypeAxis__us-gaap--RestrictedStockMember_pdd" title="Shares, Issued"&gt;13,000&lt;/span&gt; shares
of Celsion common stock to five new employees collectively. Each award has a grant date of the date of grant. Each Inducement Option
Grant has an exercise price per share equal to $&lt;span id="xdx_908_eus-gaap--ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice_c20180927__20180928__us-gaap--PlanNameAxis__custom--InducementOptionGrantsMember__srt--TitleOfIndividualAxis__custom--FiveNewEmployeesMember_pdd" title="Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price"&gt;2.77&lt;/span&gt; and $&lt;span id="xdx_907_eus-gaap--ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice_c20190218__20190219__us-gaap--PlanNameAxis__custom--InducementOptionGrantsMember__srt--TitleOfIndividualAxis__custom--FiveNewEmployeesMember_pdd" title="Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price"&gt;2.18&lt;/span&gt; which represents the closing price of Celsion&#x2019;s common stock as
reported by Nasdaq on September 28, 2018 and February 19, 2019, respectively. Each Inducement Option Grant will vest over &lt;span id="xdx_903_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1_dt_c20190218__20190219__us-gaap--PlanNameAxis__custom--InducementOptionGrantsMember__srt--TitleOfIndividualAxis__custom--FiveNewEmployeesMember_zrG17j2OBTRa" title="Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period"&gt;three years&lt;/span&gt;,
with one-third vesting on the one-year anniversary of the employee&#x2019;s first day of employment with the Company and one-third vesting
on the second and third anniversaries thereafter, subject to the new employee&#x2019;s continued service relationship with the Company
on each such date. Each Inducement Option Grant has a ten-year term and is subject to the terms and conditions of the applicable stock
option agreement. Each of Inducement Stock Grant vested on the one-year anniversary of the employee&#x2019;s first day of employment with
the Company is subject to the new employee&#x2019;s continued service relationship with the Company through such date and is subject to
the terms and conditions of the applicable restricted stock agreement.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;As
of September 30, 2021, there were a total of &lt;span id="xdx_909_eus-gaap--CommonStockCapitalSharesReservedForFutureIssuance_c20210930__us-gaap--PlanNameAxis__custom--TwoThousandAndEighteenStockIncentivePlanMember_pdd" title="Common Stock, Capital Shares Reserved for Future Issuance"&gt;14,198,424&lt;/span&gt; shares of Celsion common stock reserved for issuance under the 2018 Plan, which
were comprised of &lt;span id="xdx_90C_eus-gaap--CommonStockCapitalSharesReservedForFutureIssuance_c20210930__us-gaap--AwardTypeAxis__custom--EquityStockAwardsMember__srt--StatementScenarioAxis__custom--GrantedUnderTwoThousandEighteenPlanAndTwoThousandSevenPlanMember_pdd" title="Common Stock, Capital Shares Reserved for Future Issuance"&gt;6,473,451&lt;/span&gt; shares of Celsion common stock subject to equity awards previously granted under the 2018 Plan and 2007 Plan
and &lt;span id="xdx_909_eus-gaap--CommonStockCapitalSharesReservedForFutureIssuance_c20210930__us-gaap--PlanNameAxis__custom--TwoThousandAndEighteenPlanMember_pdd" title="Common Stock, Capital Shares Reserved for Future Issuance"&gt;7,724,973&lt;/span&gt; shares of Celsion common stock available for future issuance under the 2018 Plan. As of September 30, 2021, there were
a total of &lt;span id="xdx_905_eus-gaap--CommonStockCapitalSharesReservedForFutureIssuance_c20210930__us-gaap--AwardTypeAxis__custom--InducementAwardsMember_pdd" title="Common Stock, Capital Shares Reserved for Future Issuance"&gt;140,004&lt;/span&gt; shares of Celsion common stock subject to outstanding inducement awards.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;




&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p id="xdx_897_ecustom--SummaryOfStockOptionAndRestrictedStockAwardsTableTextBlock_zSYsZq90CVri" style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;A
summary of stock option awards and restricted stock grants for the nine-months ended September 30, 2021 is presented below:&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;span id="xdx_8BB_zdrIfqV3D5bj" style="display: none"&gt;Summary of Stock Option Awards and Restricted Stock Grants&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; border-collapse: collapse; width: 100%"&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td&gt;&#160;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="6" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;Stock Options&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&#160;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="6" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;Restricted Stock Awards&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Weighted&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Average&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Options&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Outstanding&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Weighted&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Average&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Exercise&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Price&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Non-vested&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Restricted&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Stock&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Outstanding&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Weighted&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Average&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Grant&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Date&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Fair Value&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Contractual&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Terms of&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Equity&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Awards&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;(in years)&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="width: 35%; text-align: left"&gt;Equity awards outstanding at January 1, 2021&lt;/td&gt;&lt;td style="width: 2%"&gt;&#160;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_984_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_iS_c20210101__20210930__us-gaap--AwardTypeAxis__us-gaap--EmployeeStockOptionMember_zZ6lLKf7wR0l" style="width: 9%; text-align: right" title="Number Outstanding, Outstanding, Beginning balance"&gt;4,624,725&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="width: 2%"&gt;&#160;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_988_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_iS_c20210101__20210930__us-gaap--AwardTypeAxis__us-gaap--EmployeeStockOptionMember_zFuY5PenJGzf" style="width: 9%; text-align: right" title="Weighted Average Exercise Price, Outstanding, Beginning balance"&gt;2.77&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="width: 2%"&gt;&#160;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_984_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_iS_c20210101__20210930__us-gaap--AwardTypeAxis__us-gaap--RestrictedStockMember_zWJ8mH9otqY9" style="width: 9%; text-align: right" title="Number Outstanding, Non-vested stock awards, Outstanding, Beginning balance"&gt;2,750&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="width: 2%"&gt;&#160;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_988_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_iS_c20210101__20210930__us-gaap--AwardTypeAxis__us-gaap--RestrictedStockMember_ztHPNiEsULFh" style="width: 9%; text-align: right" title="Weighted Average Grant Date Fair Value, Non-vested stock awards, Outstanding, Beginning balance"&gt;0.89&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="width: 2%"&gt;&#160;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="width: 9%; text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left"&gt;Equity awards granted&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_989_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriod_c20210101__20210930__us-gaap--AwardTypeAxis__us-gaap--EmployeeStockOptionMember_pdd" style="text-align: right" title="Number Outstanding, Options granted"&gt;2,171,250&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_985_eus-gaap--ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice_c20210101__20210930__us-gaap--AwardTypeAxis__us-gaap--EmployeeStockOptionMember_pdd" style="text-align: right" title="Weighted Average Exercise Price, Options granted"&gt;2.17&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_984_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_c20210101__20210930__us-gaap--AwardTypeAxis__us-gaap--RestrictedStockMember_pdd" style="text-align: right" title="Number Outstanding, Non-vested stock awards, Granted"&gt;9,000&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_983_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_c20210101__20210930__us-gaap--AwardTypeAxis__us-gaap--RestrictedStockMember_pdd" style="text-align: right" title="Weighted Average Grant Date Fair Value, Non-vested stock awards, Granted"&gt;1.29&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left"&gt;Equity awards exercised or vested and issued&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_98A_eus-gaap--StockIssuedDuringPeriodSharesStockOptionsExercised_iN_di_c20210101__20210930__us-gaap--AwardTypeAxis__us-gaap--EmployeeStockOptionMember_z9PnkTVWgbQf" style="text-align: right" title="Number Outstanding, Options exercised or vested and issued"&gt;(7,500&lt;/td&gt;&lt;td style="text-align: left"&gt;)&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_986_eus-gaap--ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice_c20210101__20210930__us-gaap--AwardTypeAxis__us-gaap--EmployeeStockOptionMember_pdd" style="text-align: right" title="Weighted Average Exercise Price, Options exercised or vested and issued"&gt;0.63&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_987_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_c20210101__20210930__us-gaap--AwardTypeAxis__us-gaap--RestrictedStockMember_pdd" style="text-align: right" title="Number Outstanding, Non-vested stock awards, exercised or vested and issued"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl1354"&gt;-&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_98F_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue_c20210101__20210930__us-gaap--AwardTypeAxis__us-gaap--RestrictedStockMember_pdd" style="text-align: right" title="Weighted Average Grant Date Fair Value, Non-vested stock awards, exercised or vested and issued"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl1356"&gt;-&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left; padding-bottom: 1.5pt"&gt;Equity awards forfeited, cancelled or expired&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_98E_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriod_iN_di_c20210101__20210930__us-gaap--AwardTypeAxis__us-gaap--EmployeeStockOptionMember_zaL93TmIQh9l" style="border-bottom: Black 1.5pt solid; text-align: right" title="Number Outstanding, Options canceled or expired"&gt;(185,770&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;)&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_98C_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriodWeightedAverageExercisePrice_c20210101__20210930__us-gaap--AwardTypeAxis__us-gaap--EmployeeStockOptionMember_pdd" style="text-align: right" title="Weighted Average Exercise Price, Options canceled or expired"&gt;2.59&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_981_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod_iN_di_c20210101__20210930__us-gaap--AwardTypeAxis__us-gaap--RestrictedStockMember_zUDUPzw7IfTa" style="border-bottom: Black 1.5pt solid; text-align: right" title="Number Outstanding, Non-vested stock awards, Forfeited"&gt;(1,000&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;)&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_989_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue_c20210101__20210930__us-gaap--AwardTypeAxis__us-gaap--RestrictedStockMember_pdd" style="text-align: right" title="Weighted Average Grant Date Fair Value, Non-vested stock awards, Forfeited"&gt;2.22&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left; padding-bottom: 2.5pt"&gt;Equity awards outstanding at September 30, 2021&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_985_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_iE_c20210101__20210930__us-gaap--AwardTypeAxis__us-gaap--EmployeeStockOptionMember_z4X1oy39r9Z3" style="border-bottom: Black 2.5pt double; text-align: right" title="Number Outstanding, Outstanding, Ending balance"&gt;6,602,705&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_981_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_iE_c20210101__20210930__us-gaap--AwardTypeAxis__us-gaap--EmployeeStockOptionMember_zfjWwBI3oQWe" style="text-align: right" title="Weighted Average Exercise Price, Outstanding, Ending balance"&gt;2.58&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_987_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_iE_c20210101__20210930__us-gaap--AwardTypeAxis__us-gaap--RestrictedStockMember_znosFI152YL" style="border-bottom: Black 2.5pt double; text-align: right" title="Number Outstanding, Non-vested stock awards, Outstanding, Ending balance"&gt;10,750&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_980_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_iE_c20210101__20210930__us-gaap--AwardTypeAxis__us-gaap--RestrictedStockMember_zpGqKc9jBRi" style="text-align: right" title="Weighted Average Grant Date Fair Value, Non-vested stock awards, Outstanding, Ending balance"&gt;1.33&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span id="xdx_907_eus-gaap--SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2_dtY_c20210101__20210930__us-gaap--AwardTypeAxis__us-gaap--EmployeeStockOptionMember_zs3vFLnYepRk" title="Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term"&gt;7.8&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left; padding-bottom: 2.5pt"&gt;Aggregate intrinsic value of outstanding equity awards at September 30, 2021&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_987_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue_c20210930__us-gaap--AwardTypeAxis__us-gaap--EmployeeStockOptionMember_pp0p0" style="border-bottom: Black 2.5pt double; text-align: right" title="Aggregate Intrinsic Value, Outstanding, Ending balance"&gt;2,538&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_980_eus-gaap--SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueOutstanding_c20210930__us-gaap--AwardTypeAxis__us-gaap--RestrictedStockMember_pp0p0" style="border-bottom: Black 2.5pt double; text-align: right" title="Aggregate Intrinsic Value, Non-vested stock awards, Outstanding, Ending balance"&gt;12,383&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left; padding-bottom: 2.5pt"&gt;Equity awards exercisable at September 30, 2021&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_988_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber_c20210930__us-gaap--AwardTypeAxis__us-gaap--EmployeeStockOptionMember_pdd" style="border-bottom: Black 2.5pt double; text-align: right" title="Number Outstanding, Exercisable, Ending balance"&gt;4,291,685&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_986_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice_c20210930__us-gaap--AwardTypeAxis__us-gaap--EmployeeStockOptionMember_pdd" style="text-align: right" title="Weighted Average Exercise Price, Exercisable, Ending balance"&gt;2.73&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_98D_eus-gaap--SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1_dtY_c20210101__20210930__us-gaap--AwardTypeAxis__us-gaap--EmployeeStockOptionMember_zD7Uq8wELHa3" style="text-align: right" title="Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term"&gt;7.2&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left; padding-bottom: 2.5pt"&gt;Aggregate intrinsic value of equity awards exercisable at September 30, 2021&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_983_eus-gaap--SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1_c20210930__us-gaap--AwardTypeAxis__us-gaap--EmployeeStockOptionMember_pp0p0" style="border-bottom: Black 2.5pt double; text-align: right" title="Aggregate Intrinsic Value, Exercisable, Ending balance"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl1386"&gt;-&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;

&lt;p id="xdx_8A0_z5i98dVq0PU8" style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Total
compensation cost related to stock options and restricted stock awards amounted to $&lt;span id="xdx_904_eus-gaap--AllocatedShareBasedCompensationExpense_c20210701__20210930__us-gaap--AwardTypeAxis__custom--EmployeeStockOptionAndRestrictedStockAwardsMember_pp0p0" title="Share-based Payment Arrangement, Expense"&gt;700,624&lt;/span&gt; and $&lt;span id="xdx_902_eus-gaap--AllocatedShareBasedCompensationExpense_c20200701__20200930__us-gaap--AwardTypeAxis__custom--EmployeeStockOptionAndRestrictedStockAwardsMember_pp0p0" title="Share-based Payment Arrangement, Expense"&gt;417,476&lt;/span&gt; for the three-month periods
ended September 30, 2021 and 2020, respectively. Of these amounts, $&lt;span id="xdx_90D_eus-gaap--AllocatedShareBasedCompensationExpense_c20210701__20210930__us-gaap--AwardTypeAxis__custom--EmployeeStockOptionAndRestrictedStockAwardsMember__us-gaap--IncomeStatementLocationAxis__us-gaap--ResearchAndDevelopmentExpenseMember_pp0p0" title="Share-based Payment Arrangement, Expense"&gt;241,288&lt;/span&gt; and $&lt;span id="xdx_903_eus-gaap--AllocatedShareBasedCompensationExpense_c20200701__20200930__us-gaap--AwardTypeAxis__custom--EmployeeStockOptionAndRestrictedStockAwardsMember__us-gaap--IncomeStatementLocationAxis__us-gaap--ResearchAndDevelopmentExpenseMember_pp0p0" title="Share-based Payment Arrangement, Expense"&gt;164,035&lt;/span&gt; was charged to research and development during
the three-month periods ended September 30, 2021 and 2020, respectively, and $&lt;span id="xdx_909_eus-gaap--AllocatedShareBasedCompensationExpense_c20210701__20210930__us-gaap--AwardTypeAxis__custom--EmployeeStockOptionAndRestrictedStockAwardsMember__us-gaap--IncomeStatementLocationAxis__us-gaap--GeneralAndAdministrativeExpenseMember_pp0p0" title="Share-based Payment Arrangement, Expense"&gt;459,336&lt;/span&gt; and $&lt;span id="xdx_90B_eus-gaap--AllocatedShareBasedCompensationExpense_c20200701__20200930__us-gaap--AwardTypeAxis__custom--EmployeeStockOptionAndRestrictedStockAwardsMember__us-gaap--IncomeStatementLocationAxis__us-gaap--GeneralAndAdministrativeExpenseMember_pp0p0" title="Share-based Payment Arrangement, Expense"&gt;253,441&lt;/span&gt; was charged to general and administrative
expenses during the three-month periods ended September 30, 2021 and 2020, respectively.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Total
compensation cost related to stock options and restricted stock awards amounted to $&lt;span id="xdx_90E_eus-gaap--AllocatedShareBasedCompensationExpense_c20210101__20210930__us-gaap--AwardTypeAxis__custom--EmployeeStockOptionAndRestrictedStockAwardsMember_pp0p0" title="Share-based Payment Arrangement, Expense"&gt;3,073,569&lt;/span&gt; and $&lt;span id="xdx_90C_eus-gaap--AllocatedShareBasedCompensationExpense_c20200101__20200930__us-gaap--AwardTypeAxis__custom--EmployeeStockOptionAndRestrictedStockAwardsMember_pp0p0" title="Share-based Payment Arrangement, Expense"&gt;1,448,202&lt;/span&gt; for the nine-month periods
ended September 30, 2021 and 2020, respectively. Of these amounts, $&lt;span id="xdx_907_eus-gaap--AllocatedShareBasedCompensationExpense_c20210101__20210930__us-gaap--AwardTypeAxis__custom--EmployeeStockOptionAndRestrictedStockAwardsMember__us-gaap--IncomeStatementLocationAxis__us-gaap--ResearchAndDevelopmentExpenseMember_pp0p0" title="Share-based Payment Arrangement, Expense"&gt;1,123,376&lt;/span&gt; and $&lt;span id="xdx_905_eus-gaap--AllocatedShareBasedCompensationExpense_c20200101__20200930__us-gaap--AwardTypeAxis__custom--EmployeeStockOptionAndRestrictedStockAwardsMember__us-gaap--IncomeStatementLocationAxis__us-gaap--ResearchAndDevelopmentExpenseMember_pp0p0" title="Share-based Payment Arrangement, Expense"&gt;542,157&lt;/span&gt; was charged to research and development during
the nine-month periods ended September 30, 2021 and 2020, respectively, and $&lt;span id="xdx_907_eus-gaap--AllocatedShareBasedCompensationExpense_c20210101__20210930__us-gaap--AwardTypeAxis__custom--EmployeeStockOptionAndRestrictedStockAwardsMember__us-gaap--IncomeStatementLocationAxis__us-gaap--GeneralAndAdministrativeExpenseMember_pp0p0" title="Share-based Payment Arrangement, Expense"&gt;1,950,193&lt;/span&gt; and $&lt;span id="xdx_901_eus-gaap--AllocatedShareBasedCompensationExpense_c20200101__20200930__us-gaap--AwardTypeAxis__custom--EmployeeStockOptionAndRestrictedStockAwardsMember__us-gaap--IncomeStatementLocationAxis__us-gaap--GeneralAndAdministrativeExpenseMember_pp0p0" title="Share-based Payment Arrangement, Expense"&gt;906,045&lt;/span&gt; was charged to general and administrative
expenses during the nine-month periods ended September 30, 2021 and 2020, respectively.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;As
of September 30, 2021, there was $&lt;span id="xdx_90A_eus-gaap--EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized_iI_pn5n6_c20210930_zdYmrKFy9ILh" title="Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount"&gt;2.4&lt;/span&gt; million of total unrecognized compensation cost related to non-vested stock-based compensation
arrangements. That cost is expected to be recognized over a weighted-average period of &lt;span id="xdx_901_eus-gaap--EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_dtY_c20210101__20210930_zowPQtkciLm2" title="Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition"&gt;1.0&lt;/span&gt; years. The weighted average grant date fair
values of the stock options granted was $&lt;span id="xdx_90A_eus-gaap--ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice_c20210101__20210930_zpXVfR9Wdazi" title="Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price"&gt;1.97&lt;/span&gt; and $&lt;span id="xdx_904_eus-gaap--ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice_c20200101__20200930_pdd" title="Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price"&gt;3.07&lt;/span&gt; during the nine-month periods ended September 30, 2021 and 2020, respectively.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p id="xdx_898_eus-gaap--ScheduleOfShareBasedPaymentAwardStockOptionsValuationAssumptionsTableTextBlock_z7YMoEvePzLl" style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;The
fair values of stock options granted were estimated at the date of grant using the Black-Scholes option pricing model. The Black-Scholes
model was originally developed for use in estimating the fair value of traded options, which have different characteristics from Celsion&#x2019;s
stock options. The model is also sensitive to changes in assumptions, which can materially affect the fair value estimate. The Company
used the following assumptions for determining the fair value of options granted under the Black-Scholes option pricing model:&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;span id="xdx_8BF_zPi3PU1UHhG3" style="display: none"&gt;Schedule of Assumptions Used to Determine Fair Value of Options Granted&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; border-collapse: collapse; width: 100%"&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="6" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Nine Months Ended &lt;br/&gt; September 30, &lt;/b&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: center; padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: center; font-weight: bold; padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;2021&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold; text-align: center"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: center; font-weight: bold; padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;2020&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold; text-align: center"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="width: 60%; text-align: left"&gt;Risk-free interest rate&lt;/td&gt;&lt;td style="width: 2%"&gt;&#160;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="width: 16%; text-align: right"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span id="xdx_90F_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMinimum_pid_dp_uPure_c20210101__20210930_z8U3HahBBlp5" title="Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate, Minimum"&gt;1.54&lt;/span&gt; to &lt;span id="xdx_90C_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMaximum_pid_dp_uPure_c20210101__20210930_za6zI1BeMHA9" title="Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate, Maximum"&gt;1.74&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;%&lt;/td&gt;&lt;td style="width: 2%"&gt;&#160;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="width: 16%; text-align: right"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span id="xdx_909_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMinimum_pid_dp_uPure_c20200101__20200930_zER6pxAlK3Bj" title="Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate, Minimum"&gt;0.66&lt;/span&gt; to &lt;span id="xdx_900_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMaximum_pid_dp_uPure_c20200101__20200930_zJbWSFNS9dhk" title="Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate, Maximum"&gt;1.33&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;%&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left"&gt;Expected volatility&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span id="xdx_90C_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMinimum_pid_dp_uPure_c20210101__20210930_zGE44Kt2nKU" title="Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate, Minimum"&gt;106.8&lt;/span&gt; to &lt;span id="xdx_904_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMaximum_pid_dp_uPure_c20210101__20210930_zgjYMCFzH9B3" title="Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate, Maximum"&gt;113.2&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;%&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span id="xdx_90D_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMinimum_pid_dp_uPure_c20200101__20200930_z5g2JDuKZgki" title="Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate, Minimum"&gt;100.4&lt;/span&gt; to &lt;span id="xdx_90E_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMaximum_pid_dp_uPure_c20200101__20200930_z6NqLDYb2Fxk" title="Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate, Maximum"&gt;104.8&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;%&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left"&gt;Expected life (in years)&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span id="xdx_905_eus-gaap--SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1_dtY_c20210101__20210930__srt--RangeAxis__srt--MinimumMember_zubMLmUEhDf1" title="Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term"&gt;7.5&lt;/span&gt; to &lt;span id="xdx_901_eus-gaap--SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1_dtY_c20210101__20210930__srt--RangeAxis__srt--MaximumMember_zZ9wsGqKEkec" title="Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term"&gt;10.0&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;span id="xdx_901_eus-gaap--SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1_dtY_c20200101__20200930__srt--RangeAxis__srt--MinimumMember_zWAuQ6e2O64c" title="Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term"&gt;8.0&lt;/span&gt; to &lt;span id="xdx_901_eus-gaap--SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1_dtY_c20200101__20200930__srt--RangeAxis__srt--MaximumMember_zDLXDVZUwyTg" title="Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term"&gt;10.0&lt;/span&gt; &lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left"&gt;Expected dividend yield&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_985_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate_pid_dp_uPure_c20210101__20210930_zqr5nHMPM4Bc" style="text-align: right" title="Expected dividend yield"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl1446"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;%&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_98A_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate_pid_dp_uPure_c20200101__20200930_zCetLEcwqMi" style="text-align: right" title="Expected dividend yield"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl1448"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;%&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;

&lt;p id="xdx_8A1_zbcQZ1Y10IM9" style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"/&gt;&lt;/p&gt;



&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Expected
volatilities utilized in the model are based on historical volatility of the Company&#x2019;s stock price. The risk-free interest rate
is derived from values assigned to U.S. Treasury bonds with terms that approximate the expected option lives in effect at the time of
grant.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

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      decimals="INF"
      unitRef="Shares">3900000</us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant>
    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant
      contextRef="AsOf2020-06-15_custom_TwoThousandAndEighteenStockIncentivePlanMember_srt_MinimumMember"
      decimals="INF"
      unitRef="Shares">2500000</us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant>
    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant
      contextRef="AsOf2020-06-15_custom_TwoThousandAndEighteenStockIncentivePlanMember_srt_MaximumMember"
      decimals="INF"
      unitRef="Shares">6400000</us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant>
    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant
      contextRef="AsOf2021-06-10_custom_TwoThousandAndEighteenStockIncentivePlanMember_srt_MinimumMember"
      decimals="INF"
      unitRef="Shares">7700000</us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant>
    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant
      contextRef="AsOf2021-06-10_custom_TwoThousandAndEighteenStockIncentivePlanMember_srt_MaximumMember"
      decimals="INF"
      unitRef="Shares">14100000</us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant>
    <CLSN:StockOptionsStrikePriceDescription contextRef="From2021-01-012021-09-30_custom_TwoThousandSevenStockIncentivePlanMember">Options are generally granted
with strike prices equal to the fair market value of a share of Celsion common stock on the date of grant. Incentive stock options may
be granted to purchase shares of common stock at a price not less than 100% of the fair market value of the underlying shares on the
date of grant, provided that the exercise price of any incentive stock option granted to an eligible employee owning more than 10% of
the outstanding stock of Celsion must be at least 110% of such fair market value on the date of grant. Only officers and key employees
may receive incentive stock options.</CLSN:StockOptionsStrikePriceDescription>
    <us-gaap:SharesIssued
      contextRef="AsOf2018-09-28_custom_InducementOptionGrantsMember_custom_FiveNewEmployeesMember_us-gaap_CommonStockMember"
      decimals="INF"
      unitRef="Shares">164004</us-gaap:SharesIssued>
    <us-gaap:SharesIssued
      contextRef="AsOf2019-02-19_custom_InducementOptionGrantsMember_custom_FiveNewEmployeesMember_us-gaap_CommonStockMember"
      decimals="INF"
      unitRef="Shares">140004</us-gaap:SharesIssued>
    <us-gaap:SharesIssued
      contextRef="AsOf2018-09-28_custom_InducementOptionGrantsMember_custom_FiveNewEmployeesMember_us-gaap_RestrictedStockMember"
      decimals="INF"
      unitRef="Shares">19000</us-gaap:SharesIssued>
    <us-gaap:SharesIssued
      contextRef="AsOf2019-02-19_custom_InducementOptionGrantsMember_custom_FiveNewEmployeesMember_us-gaap_RestrictedStockMember"
      decimals="INF"
      unitRef="Shares">13000</us-gaap:SharesIssued>
    <us-gaap:ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice
      contextRef="From2018-09-272018-09-28_custom_InducementOptionGrantsMember_custom_FiveNewEmployeesMember"
      decimals="INF"
      unitRef="USDPShares">2.77</us-gaap:ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice>
    <us-gaap:ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice
      contextRef="From2019-02-182019-02-19_custom_InducementOptionGrantsMember_custom_FiveNewEmployeesMember"
      decimals="INF"
      unitRef="USDPShares">2.18</us-gaap:ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice>
    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1 contextRef="From2019-02-182019-02-19_custom_InducementOptionGrantsMember_custom_FiveNewEmployeesMember">P3Y</us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1>
    <us-gaap:CommonStockCapitalSharesReservedForFutureIssuance
      contextRef="AsOf2021-09-30_custom_TwoThousandAndEighteenStockIncentivePlanMember"
      decimals="INF"
      unitRef="Shares">14198424</us-gaap:CommonStockCapitalSharesReservedForFutureIssuance>
    <us-gaap:CommonStockCapitalSharesReservedForFutureIssuance
      contextRef="AsOf2021-09-30_custom_EquityStockAwardsMember_custom_GrantedUnderTwoThousandEighteenPlanAndTwoThousandSevenPlanMember"
      decimals="INF"
      unitRef="Shares">6473451</us-gaap:CommonStockCapitalSharesReservedForFutureIssuance>
    <us-gaap:CommonStockCapitalSharesReservedForFutureIssuance
      contextRef="AsOf2021-09-30_custom_TwoThousandAndEighteenPlanMember"
      decimals="INF"
      unitRef="Shares">7724973</us-gaap:CommonStockCapitalSharesReservedForFutureIssuance>
    <us-gaap:CommonStockCapitalSharesReservedForFutureIssuance
      contextRef="AsOf2021-09-30_custom_InducementAwardsMember"
      decimals="INF"
      unitRef="Shares">140004</us-gaap:CommonStockCapitalSharesReservedForFutureIssuance>
    <CLSN:SummaryOfStockOptionAndRestrictedStockAwardsTableTextBlock contextRef="From2021-01-01to2021-09-30">&lt;p id="xdx_897_ecustom--SummaryOfStockOptionAndRestrictedStockAwardsTableTextBlock_zSYsZq90CVri" style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;A
summary of stock option awards and restricted stock grants for the nine-months ended September 30, 2021 is presented below:&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;span id="xdx_8BB_zdrIfqV3D5bj" style="display: none"&gt;Summary of Stock Option Awards and Restricted Stock Grants&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; border-collapse: collapse; width: 100%"&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td&gt;&#160;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="6" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;Stock Options&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&#160;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="6" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;Restricted Stock Awards&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Weighted&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Average&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Options&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Outstanding&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Weighted&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Average&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Exercise&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Price&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Non-vested&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Restricted&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Stock&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Outstanding&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Weighted&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Average&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Grant&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Date&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Fair Value&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Contractual&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Terms of&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Equity&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Awards&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;(in years)&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="width: 35%; text-align: left"&gt;Equity awards outstanding at January 1, 2021&lt;/td&gt;&lt;td style="width: 2%"&gt;&#160;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_984_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_iS_c20210101__20210930__us-gaap--AwardTypeAxis__us-gaap--EmployeeStockOptionMember_zZ6lLKf7wR0l" style="width: 9%; text-align: right" title="Number Outstanding, Outstanding, Beginning balance"&gt;4,624,725&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="width: 2%"&gt;&#160;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_988_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_iS_c20210101__20210930__us-gaap--AwardTypeAxis__us-gaap--EmployeeStockOptionMember_zFuY5PenJGzf" style="width: 9%; text-align: right" title="Weighted Average Exercise Price, Outstanding, Beginning balance"&gt;2.77&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="width: 2%"&gt;&#160;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_984_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_iS_c20210101__20210930__us-gaap--AwardTypeAxis__us-gaap--RestrictedStockMember_zWJ8mH9otqY9" style="width: 9%; text-align: right" title="Number Outstanding, Non-vested stock awards, Outstanding, Beginning balance"&gt;2,750&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="width: 2%"&gt;&#160;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_988_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_iS_c20210101__20210930__us-gaap--AwardTypeAxis__us-gaap--RestrictedStockMember_ztHPNiEsULFh" style="width: 9%; text-align: right" title="Weighted Average Grant Date Fair Value, Non-vested stock awards, Outstanding, Beginning balance"&gt;0.89&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="width: 2%"&gt;&#160;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="width: 9%; text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left"&gt;Equity awards granted&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_989_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriod_c20210101__20210930__us-gaap--AwardTypeAxis__us-gaap--EmployeeStockOptionMember_pdd" style="text-align: right" title="Number Outstanding, Options granted"&gt;2,171,250&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_985_eus-gaap--ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice_c20210101__20210930__us-gaap--AwardTypeAxis__us-gaap--EmployeeStockOptionMember_pdd" style="text-align: right" title="Weighted Average Exercise Price, Options granted"&gt;2.17&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_984_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_c20210101__20210930__us-gaap--AwardTypeAxis__us-gaap--RestrictedStockMember_pdd" style="text-align: right" title="Number Outstanding, Non-vested stock awards, Granted"&gt;9,000&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_983_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_c20210101__20210930__us-gaap--AwardTypeAxis__us-gaap--RestrictedStockMember_pdd" style="text-align: right" title="Weighted Average Grant Date Fair Value, Non-vested stock awards, Granted"&gt;1.29&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left"&gt;Equity awards exercised or vested and issued&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_98A_eus-gaap--StockIssuedDuringPeriodSharesStockOptionsExercised_iN_di_c20210101__20210930__us-gaap--AwardTypeAxis__us-gaap--EmployeeStockOptionMember_z9PnkTVWgbQf" style="text-align: right" title="Number Outstanding, Options exercised or vested and issued"&gt;(7,500&lt;/td&gt;&lt;td style="text-align: left"&gt;)&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_986_eus-gaap--ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice_c20210101__20210930__us-gaap--AwardTypeAxis__us-gaap--EmployeeStockOptionMember_pdd" style="text-align: right" title="Weighted Average Exercise Price, Options exercised or vested and issued"&gt;0.63&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_987_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_c20210101__20210930__us-gaap--AwardTypeAxis__us-gaap--RestrictedStockMember_pdd" style="text-align: right" title="Number Outstanding, Non-vested stock awards, exercised or vested and issued"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl1354"&gt;-&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_98F_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue_c20210101__20210930__us-gaap--AwardTypeAxis__us-gaap--RestrictedStockMember_pdd" style="text-align: right" title="Weighted Average Grant Date Fair Value, Non-vested stock awards, exercised or vested and issued"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl1356"&gt;-&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left; padding-bottom: 1.5pt"&gt;Equity awards forfeited, cancelled or expired&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_98E_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriod_iN_di_c20210101__20210930__us-gaap--AwardTypeAxis__us-gaap--EmployeeStockOptionMember_zaL93TmIQh9l" style="border-bottom: Black 1.5pt solid; text-align: right" title="Number Outstanding, Options canceled or expired"&gt;(185,770&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;)&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_98C_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriodWeightedAverageExercisePrice_c20210101__20210930__us-gaap--AwardTypeAxis__us-gaap--EmployeeStockOptionMember_pdd" style="text-align: right" title="Weighted Average Exercise Price, Options canceled or expired"&gt;2.59&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_981_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod_iN_di_c20210101__20210930__us-gaap--AwardTypeAxis__us-gaap--RestrictedStockMember_zUDUPzw7IfTa" style="border-bottom: Black 1.5pt solid; text-align: right" title="Number Outstanding, Non-vested stock awards, Forfeited"&gt;(1,000&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;)&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_989_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue_c20210101__20210930__us-gaap--AwardTypeAxis__us-gaap--RestrictedStockMember_pdd" style="text-align: right" title="Weighted Average Grant Date Fair Value, Non-vested stock awards, Forfeited"&gt;2.22&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left; padding-bottom: 2.5pt"&gt;Equity awards outstanding at September 30, 2021&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_985_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_iE_c20210101__20210930__us-gaap--AwardTypeAxis__us-gaap--EmployeeStockOptionMember_z4X1oy39r9Z3" style="border-bottom: Black 2.5pt double; text-align: right" title="Number Outstanding, Outstanding, Ending balance"&gt;6,602,705&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_981_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_iE_c20210101__20210930__us-gaap--AwardTypeAxis__us-gaap--EmployeeStockOptionMember_zfjWwBI3oQWe" style="text-align: right" title="Weighted Average Exercise Price, Outstanding, Ending balance"&gt;2.58&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_987_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_iE_c20210101__20210930__us-gaap--AwardTypeAxis__us-gaap--RestrictedStockMember_znosFI152YL" style="border-bottom: Black 2.5pt double; text-align: right" title="Number Outstanding, Non-vested stock awards, Outstanding, Ending balance"&gt;10,750&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_980_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_iE_c20210101__20210930__us-gaap--AwardTypeAxis__us-gaap--RestrictedStockMember_zpGqKc9jBRi" style="text-align: right" title="Weighted Average Grant Date Fair Value, Non-vested stock awards, Outstanding, Ending balance"&gt;1.33&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span id="xdx_907_eus-gaap--SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2_dtY_c20210101__20210930__us-gaap--AwardTypeAxis__us-gaap--EmployeeStockOptionMember_zs3vFLnYepRk" title="Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term"&gt;7.8&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left; padding-bottom: 2.5pt"&gt;Aggregate intrinsic value of outstanding equity awards at September 30, 2021&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_987_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue_c20210930__us-gaap--AwardTypeAxis__us-gaap--EmployeeStockOptionMember_pp0p0" style="border-bottom: Black 2.5pt double; text-align: right" title="Aggregate Intrinsic Value, Outstanding, Ending balance"&gt;2,538&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_980_eus-gaap--SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueOutstanding_c20210930__us-gaap--AwardTypeAxis__us-gaap--RestrictedStockMember_pp0p0" style="border-bottom: Black 2.5pt double; text-align: right" title="Aggregate Intrinsic Value, Non-vested stock awards, Outstanding, Ending balance"&gt;12,383&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left; padding-bottom: 2.5pt"&gt;Equity awards exercisable at September 30, 2021&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_988_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber_c20210930__us-gaap--AwardTypeAxis__us-gaap--EmployeeStockOptionMember_pdd" style="border-bottom: Black 2.5pt double; text-align: right" title="Number Outstanding, Exercisable, Ending balance"&gt;4,291,685&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_986_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice_c20210930__us-gaap--AwardTypeAxis__us-gaap--EmployeeStockOptionMember_pdd" style="text-align: right" title="Weighted Average Exercise Price, Exercisable, Ending balance"&gt;2.73&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_98D_eus-gaap--SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1_dtY_c20210101__20210930__us-gaap--AwardTypeAxis__us-gaap--EmployeeStockOptionMember_zD7Uq8wELHa3" style="text-align: right" title="Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term"&gt;7.2&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left; padding-bottom: 2.5pt"&gt;Aggregate intrinsic value of equity awards exercisable at September 30, 2021&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_983_eus-gaap--SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1_c20210930__us-gaap--AwardTypeAxis__us-gaap--EmployeeStockOptionMember_pp0p0" style="border-bottom: Black 2.5pt double; text-align: right" title="Aggregate Intrinsic Value, Exercisable, Ending balance"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl1386"&gt;-&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;

</CLSN:SummaryOfStockOptionAndRestrictedStockAwardsTableTextBlock>
    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber
      contextRef="AsOf2020-12-31_us-gaap_EmployeeStockOptionMember"
      decimals="INF"
      unitRef="Shares">4624725</us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber>
    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice
      contextRef="AsOf2020-12-31_us-gaap_EmployeeStockOptionMember"
      decimals="INF"
      unitRef="USDPShares">2.77</us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice>
    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber
      contextRef="AsOf2020-12-31_us-gaap_RestrictedStockMember"
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    <us-gaap:ScheduleOfShareBasedPaymentAwardStockOptionsValuationAssumptionsTableTextBlock contextRef="From2021-01-01to2021-09-30">&lt;p id="xdx_898_eus-gaap--ScheduleOfShareBasedPaymentAwardStockOptionsValuationAssumptionsTableTextBlock_z7YMoEvePzLl" style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;The
fair values of stock options granted were estimated at the date of grant using the Black-Scholes option pricing model. The Black-Scholes
model was originally developed for use in estimating the fair value of traded options, which have different characteristics from Celsion&#x2019;s
stock options. The model is also sensitive to changes in assumptions, which can materially affect the fair value estimate. The Company
used the following assumptions for determining the fair value of options granted under the Black-Scholes option pricing model:&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;span id="xdx_8BF_zPi3PU1UHhG3" style="display: none"&gt;Schedule of Assumptions Used to Determine Fair Value of Options Granted&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

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  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="6" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Nine Months Ended &lt;br/&gt; September 30, &lt;/b&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: center; padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: center; font-weight: bold; padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;2021&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold; text-align: center"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: center; font-weight: bold; padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;2020&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold; text-align: center"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
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    &lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="width: 16%; text-align: right"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span id="xdx_90F_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMinimum_pid_dp_uPure_c20210101__20210930_z8U3HahBBlp5" title="Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate, Minimum"&gt;1.54&lt;/span&gt; to &lt;span id="xdx_90C_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMaximum_pid_dp_uPure_c20210101__20210930_za6zI1BeMHA9" title="Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate, Maximum"&gt;1.74&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;%&lt;/td&gt;&lt;td style="width: 2%"&gt;&#160;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="width: 16%; text-align: right"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span id="xdx_909_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMinimum_pid_dp_uPure_c20200101__20200930_zER6pxAlK3Bj" title="Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate, Minimum"&gt;0.66&lt;/span&gt; to &lt;span id="xdx_900_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMaximum_pid_dp_uPure_c20200101__20200930_zJbWSFNS9dhk" title="Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate, Maximum"&gt;1.33&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;%&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left"&gt;Expected volatility&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
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  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left"&gt;Expected life (in years)&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
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    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;span id="xdx_901_eus-gaap--SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1_dtY_c20200101__20200930__srt--RangeAxis__srt--MinimumMember_zWAuQ6e2O64c" title="Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term"&gt;8.0&lt;/span&gt; to &lt;span id="xdx_901_eus-gaap--SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1_dtY_c20200101__20200930__srt--RangeAxis__srt--MaximumMember_zDLXDVZUwyTg" title="Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term"&gt;10.0&lt;/span&gt; &lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left"&gt;Expected dividend yield&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_985_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate_pid_dp_uPure_c20210101__20210930_zqr5nHMPM4Bc" style="text-align: right" title="Expected dividend yield"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl1446"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;%&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_98A_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate_pid_dp_uPure_c20200101__20200930_zCetLEcwqMi" style="text-align: right" title="Expected dividend yield"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl1448"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;%&lt;/td&gt;&lt;/tr&gt;
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    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMinimum
      contextRef="From2020-01-012020-09-30"
      decimals="INF"
      unitRef="Pure">1.004</us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMinimum>
    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMaximum
      contextRef="From2020-01-012020-09-30"
      decimals="INF"
      unitRef="Pure">1.048</us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMaximum>
    <us-gaap:SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1 contextRef="From2021-01-012021-09-30_srt_MinimumMember">P7Y6M</us-gaap:SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1>
    <us-gaap:SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1 contextRef="From2021-01-012021-09-30_srt_MaximumMember">P10Y</us-gaap:SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1>
    <us-gaap:SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1 contextRef="From2020-01-012020-09-30_srt_MinimumMember">P8Y</us-gaap:SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1>
    <us-gaap:SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1 contextRef="From2020-01-012020-09-30_srt_MaximumMember">P10Y</us-gaap:SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1>
    <CLSN:EarnoutMilestoneLiabilityDisclosureTextBlock contextRef="From2021-01-01to2021-09-30">&lt;p id="xdx_808_ecustom--EarnoutMilestoneLiabilityDisclosureTextBlock_z2qnIzBRo6of" style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Note
14. &lt;span id="xdx_823_zsbc6Rubz7fj"&gt;Earn-Out Milestone Liability&lt;/span&gt;&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;On
March 28, 2019, the Company and EGWU, Inc. entered into an amendment to its purchase agreement (&#x201c;Amended Asset Purchase Agreement&#x201d;),
whereby payment of the earnout milestone liability related to the Ovarian Cancer Indication of $&lt;span id="xdx_902_ecustom--EarnoutMilestoneLiability1_c20190328__us-gaap--TypeOfArrangementAxis__custom--AmendedAssetPurchaseAgreementMember__us-gaap--RelatedPartyTransactionAxis__custom--AchievingMilestoneWithInOneYearMember_pn5n6" title="Earnout milestone liability"&gt;12.4&lt;/span&gt; million had been modified. The Company
has the option to make the payment as follows:&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; width: 100%; border-collapse: collapse"&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: top"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; width: 24px; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;a)&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;$&lt;span id="xdx_90D_ecustom--EarnoutMilestoneLiability1_iI_pn6n6_c20190328__us-gaap--TypeOfArrangementAxis__custom--AmendedAssetPurchaseAgreementMember__us-gaap--RelatedPartyTransactionAxis__custom--CertainBusinessDaysOfAchievingMilestoneMember_zjrJ9aNXGYCi" title="Earnout milestone liability"&gt;7.0&lt;/span&gt;
    million in cash within 10 business days of achieving the milestone; or&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: top"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;b)&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;$&lt;span id="xdx_904_ecustom--EarnoutMilestoneLiability1_c20190328__us-gaap--TypeOfArrangementAxis__custom--AmendedAssetPurchaseAgreementMember_pn5n6" title="Earnout milestone liability"&gt;12.4&lt;/span&gt;
    million in cash, common stock of the Company, or a combination of either, within one year of achieving the milestone.&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;
&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;As
of September 30, 2021, June 30, 2021, and December 31, 2020, the Company calculated the fair value of the earn-out milestone liability
at $&lt;span id="xdx_909_eus-gaap--BusinessCombinationConsiderationTransferredLiabilitiesIncurred_c20210101__20210930__us-gaap--BusinessAcquisitionAxis__custom--EGWCMember__us-gaap--TypeOfArrangementAxis__custom--FairValueEarnoutMilestoneLiabilityMember_pn5n6" title="Business Combination, Consideration Transferred, Liabilities Incurred"&gt;7.3&lt;/span&gt; million, $&lt;span id="xdx_90E_eus-gaap--BusinessCombinationConsiderationTransferredLiabilitiesIncurred_pn5n6_c20210101__20210630__us-gaap--BusinessAcquisitionAxis__custom--EGWCMember__us-gaap--TypeOfArrangementAxis__custom--FairValueEarnoutMilestoneLiabilityMember_z0atnmTlaBic" title="Business Combination, Consideration Transferred, Liabilities Incurred"&gt;7.1&lt;/span&gt; million and $&lt;span id="xdx_90E_eus-gaap--BusinessCombinationConsiderationTransferredLiabilitiesIncurred_pn6n6_c20200101__20201231__us-gaap--BusinessAcquisitionAxis__custom--EGWCMember__us-gaap--TypeOfArrangementAxis__custom--FairValueEarnoutMilestoneLiabilityMember_zPUIZm1KrWth" title="Business Combination, Consideration Transferred, Liabilities Incurred"&gt;7.0&lt;/span&gt; million, respectively, and recognized a non-cash charge of $&lt;span id="xdx_90E_ecustom--NoncashChargeOnEarnoutMilestoneLiability_c20210701__20210930__us-gaap--BusinessAcquisitionAxis__custom--EGWCMember_pn5n6" title="Non-cash charge on earnout milestone liability"&gt;&lt;span id="xdx_900_ecustom--NoncashChargeOnEarnoutMilestoneLiability_c20210101__20210930__us-gaap--BusinessAcquisitionAxis__custom--EGWCMember_pn5n6" title="Non-cash charge on earnout milestone liability"&gt;0.3&lt;/span&gt;&lt;/span&gt; million and for each of the three-months
and nine months ended September 30, 2021. &lt;span id="xdx_901_ecustom--EarnoutPaymentOptionsDescription_c20210101__20210930__us-gaap--BusinessAcquisitionAxis__custom--EGWCMember" title="Earnout payment options description"&gt;In assessing the earnout milestone liability at September 30, 2021 and June 30, 2021, the Company
determined the fair value of each of the two payment options per the Amended Asset Purchase Agreement and weighted them at 50% and 50%
probability for the $7.0 million and the $12.4 million payments, respectively.&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;As
of September 30, 2020, June 30, 2020 and December 31, 2019, the Company calculated the fair value of the earn-out milestone liability
at $&lt;span id="xdx_90A_eus-gaap--BusinessCombinationConsiderationTransferredLiabilitiesIncurred_pn5n6_c20200101__20200930__us-gaap--BusinessAcquisitionAxis__custom--EGWCMember__us-gaap--TypeOfArrangementAxis__custom--FairValueEarnoutMilestoneLiabilityMember_zbsc01IRdpcc" title="Business Combination, Consideration Transferred, Liabilities Incurred"&gt;7.1&lt;/span&gt; million, $&lt;span id="xdx_904_eus-gaap--BusinessCombinationConsiderationTransferredLiabilitiesIncurred_pn5n6_c20200101__20200630__us-gaap--BusinessAcquisitionAxis__custom--EGWCMember__us-gaap--TypeOfArrangementAxis__custom--FairValueEarnoutMilestoneLiabilityMember_zDs8NMLs7yN8" title="Business Combination, Consideration Transferred, Liabilities Incurred"&gt;6.0&lt;/span&gt; million, and $&lt;span id="xdx_909_eus-gaap--BusinessCombinationConsiderationTransferredLiabilitiesIncurred_pn5n6_c20190101__20191231__us-gaap--BusinessAcquisitionAxis__custom--EGWCMember__us-gaap--TypeOfArrangementAxis__custom--FairValueEarnoutMilestoneLiabilityMember_zPBXcsBxFCj5" title="Business Combination, Consideration Transferred, Liabilities Incurred"&gt;5.7&lt;/span&gt; million, respectively, and recognized a non-cash charge of $&lt;span id="xdx_90A_ecustom--NoncashChargeOnEarnoutMilestoneLiability_pn5n6_c20200701__20200930__us-gaap--BusinessAcquisitionAxis__custom--EGWCMember_zxODRi9lXHvk" title="Non-cash charge on earnout milestone liability"&gt;1.1&lt;/span&gt; and $&lt;span id="xdx_906_ecustom--NoncashChargeOnEarnoutMilestoneLiability_pn5n6_c20200101__20200930__us-gaap--BusinessAcquisitionAxis__custom--EGWCMember_z75rR3JUYzx3" title="Non-cash charge on earnout milestone liability"&gt;1.4&lt;/span&gt; million for the three-month
and nine-month periods ended September 30, 2020, respectively. &lt;span id="xdx_90F_ecustom--EarnoutPaymentOptionsDescription_c20200101__20200930__us-gaap--BusinessAcquisitionAxis__custom--EGWCMember" title="Earnout payment options description"&gt;In assessing the earnout milestone liability at September 30, 2020, the
Company fair valued each of the two payment options per the Amended Asset Purchase Agreement and weighted them at 50% and 50% probability
for the $7.0 million and the $12.4 million payments, respectively, and at June 30, 2020, the Company determined the fair value of each
of the two payment options per the Amended Asset Purchase Agreement and weighted them at 80% and 20% probability for the $7.0 million
and the $12.4 million payments, respectively.&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p id="xdx_89F_ecustom--ScheduleOfChangesInEarnOutMilestoneLiabilitiesTableTextBlock_z6P8YoyfqFQa" style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;The
following is a summary of the changes in the earn-out milestone liability for the nine-month period ended September 30, 2021:&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;span id="xdx_8BB_zJaNC2oL9zYd" style="display: none"&gt;Schedule of Changes in Earn-out Milestone Liability&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; border-collapse: collapse; width: 100%"&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="width: 80%"&gt;Balance at January 1, 2021&lt;/td&gt;&lt;td style="width: 2%"&gt;&#160;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_98A_ecustom--EarnoutMilestoneLiability_iS_c20210101__20210930_zpcwF9poQBWg" style="width: 16%; text-align: right" title="Earn-out liabilities, beginning balance"&gt;(7,018,000&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;)&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left; padding-bottom: 1.5pt"&gt;Non-cash loss from the change in fair value&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_987_ecustom--GainLossFromChangeInFairValueOfEarnOutMilestoneLiability_c20210101__20210930_pp0p0" style="border-bottom: Black 1.5pt solid; text-align: right" title="Non-cash gain loss from the adjustment for the change in fair value"&gt;(327,000&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;)&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="padding-bottom: 2.5pt"&gt;Balance at September 30, 2021&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_983_ecustom--EarnoutMilestoneLiability_iE_pp0p0_c20210101__20210930_zhHtqewkWQT" style="border-bottom: Black 2.5pt double; text-align: right" title="Earn-out liabilities, ending balance"&gt;(7,345,000&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;)&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;

&lt;p id="xdx_8A5_zINCCIiZyq48" style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p id="xdx_89E_ecustom--ScheduleOfRiskadjustmentAssessmentTableTextBlock_zUkshKqCzlL1" style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;The
following is a schedule of the Company&#x2019;s risk-adjustment assessment of each milestone:&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;span id="xdx_8BB_zEShiugTzqbg" style="display: none"&gt;Schedule of Risk Adjustment Assessment&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"/&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; border-collapse: collapse; width: 100%"&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: center"&gt;Date&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Risk-adjustment Assessment&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;of Achieving Each Milestone&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;Discount Rate&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Estimated Time&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;to Achieve&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td style="text-align: justify"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" style="text-align: center"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" style="text-align: center"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: center"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: justify; width: 36%"&gt;September 30, 2021&lt;/td&gt;&lt;td style="width: 2%"&gt;&#160;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_982_ecustom--RiskadjustmentAssessmentOfAchievingMilestone_pid_dp_uPure_c20210101__20210930_ze0FEABLQXP3" style="width: 18%; text-align: right" title="Risk-adjustment Assessment of achieving each Milestone"&gt;80&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;%&lt;/td&gt;&lt;td style="width: 2%"&gt;&#160;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="width: 18%; text-align: right"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span id="xdx_900_ecustom--DiscountRatesOnMileStoneLiabilities_pid_dp_uPure_c20210101__20210930__srt--RangeAxis__srt--MinimumMember_zDYsFxRz7St2" title="Discount Rate"&gt;6.54&lt;/span&gt;% to &lt;span id="xdx_902_ecustom--DiscountRatesOnMileStoneLiabilities_pid_dp_uPure_c20210101__20210930__srt--RangeAxis__srt--MaximumMember_zwWGBvW0EU4d"&gt;6.60&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;%&lt;/td&gt;&lt;td style="width: 2%"&gt;&#160;&lt;/td&gt;
    &lt;td style="width: 18%; text-align: right"&gt;&lt;span id="xdx_902_ecustom--EstimatedTimeToAchieveMileStone_dtY_c20210101__20210930__srt--RangeAxis__srt--MinimumMember_z9ETKy69Bsmg" title="Estimated time to achieve mile stone"&gt;0.29&lt;/span&gt; to &lt;span id="xdx_90A_ecustom--EstimatedTimeToAchieveMileStone_dtY_c20210101__20210930__srt--RangeAxis__srt--MaximumMember_zlGGuOSofXQ8" title="Estimated time to achieve mile stone"&gt;1.29&lt;/span&gt; years&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: justify"&gt;June 30, 2021&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_98A_ecustom--RiskadjustmentAssessmentOfAchievingMilestone_pid_dp_uPure_c20210101__20210630_zrPOhEHYrI9i" style="text-align: right" title="Risk-adjustment Assessment of achieving each Milestone"&gt;80&lt;/td&gt;&lt;td style="text-align: left"&gt;%&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_98A_ecustom--DiscountRatesOnMileStoneLiabilities_pid_dp_uPure_c20210101__20210630_zrm6J6DLrWzg" style="text-align: right" title="Discount Rate"&gt;9&lt;/td&gt;&lt;td style="text-align: left"&gt;%&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: right"&gt;&lt;span id="xdx_901_ecustom--EstimatedTimeToAchieveMileStone_dtY_c20210101__20210630__srt--RangeAxis__srt--MinimumMember_zF8WoRh5NZa" title="[custom:EstimatedTimeToAchieveMileStone]"&gt;0.42&lt;/span&gt; to &lt;span id="xdx_908_ecustom--EstimatedTimeToAchieveMileStone_dtY_c20210101__20210630__srt--RangeAxis__srt--MaximumMember_zErCy2KQRwkj" title="[custom:EstimatedTimeToAchieveMileStone]"&gt;1.42&lt;/span&gt; years&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: justify"&gt;December 31, 2020&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_98C_ecustom--RiskadjustmentAssessmentOfAchievingMilestone_pid_dp_uPure_c20200101__20201231_z013cfBO3t73" style="text-align: right" title="Risk-adjustment Assessment of achieving each Milestone"&gt;80&lt;/td&gt;&lt;td style="text-align: left"&gt;%&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_98D_ecustom--DiscountRatesOnMileStoneLiabilities_pid_dp_uPure_c20200101__20201231_ztbvNDAT1wj8" style="text-align: right" title="Discount Rate"&gt;9&lt;/td&gt;&lt;td style="text-align: left"&gt;%&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: right"&gt;&lt;span id="xdx_908_ecustom--EstimatedTimeToAchieveMileStone_dtY_c20200101__20201231__srt--RangeAxis__srt--MinimumMember_zix4UkxrlDbg" title="[custom:EstimatedTimeToAchieveMileStone]"&gt;0.54&lt;/span&gt; to &lt;span id="xdx_907_ecustom--EstimatedTimeToAchieveMileStone_dtY_c20200101__20201231__srt--RangeAxis__srt--MaximumMember_zhoB79ftHQUc" title="[custom:EstimatedTimeToAchieveMileStone]"&gt;1.54&lt;/span&gt; years&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: justify"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: justify"&gt;September 30, 2020&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_985_ecustom--RiskadjustmentAssessmentOfAchievingMilestone_pid_dp_uPure_c20200101__20200930_zDqTVXnnzWHk" style="text-align: right" title="Risk-adjustment Assessment of achieving each Milestone"&gt;80&lt;/td&gt;&lt;td style="text-align: left"&gt;%&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_986_ecustom--DiscountRatesOnMileStoneLiabilities_pid_dp_uPure_c20200101__20200930_zZU8o9IPcC1i" style="text-align: right" title="Discount Rate"&gt;9&lt;/td&gt;&lt;td style="text-align: left"&gt;%&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: right"&gt;&lt;span id="xdx_903_ecustom--EstimatedTimeToAchieveMileStone_dtY_c20200101__20200930__srt--RangeAxis__srt--MinimumMember_zDpK3V0UFHMd" title="[custom:EstimatedTimeToAchieveMileStone]"&gt;0.38&lt;/span&gt; to &lt;span id="xdx_90A_ecustom--EstimatedTimeToAchieveMileStone_dtY_c20200101__20200930__srt--RangeAxis__srt--MaximumMember_z8H6RyZWFlb2" title="[custom:EstimatedTimeToAchieveMileStone]"&gt;1.38&lt;/span&gt; years&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: justify"&gt;June 30, 2020&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_982_ecustom--RiskadjustmentAssessmentOfAchievingMilestone_pid_dp_uPure_c20200101__20200630_zfaMBL2p4fM1" style="text-align: right" title="Risk-adjustment Assessment of achieving each Milestone"&gt;80&lt;/td&gt;&lt;td style="text-align: left"&gt;%&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_98E_ecustom--DiscountRatesOnMileStoneLiabilities_pid_dp_uPure_c20200101__20200630_zPYh3VXJkvVg" style="text-align: right" title="Discount Rate"&gt;9&lt;/td&gt;&lt;td style="text-align: left"&gt;%&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: right"&gt;&lt;span id="xdx_90E_ecustom--EstimatedTimeToAchieveMileStone_dtY_c20200101__20200630__srt--RangeAxis__srt--MinimumMember_zKbxtNExTShc" title="[custom:EstimatedTimeToAchieveMileStone]"&gt;0.54&lt;/span&gt; to &lt;span id="xdx_900_ecustom--EstimatedTimeToAchieveMileStone_dtY_c20200101__20200630__srt--RangeAxis__srt--MaximumMember_zFQLKU0EqDn" title="[custom:EstimatedTimeToAchieveMileStone]"&gt;1.54&lt;/span&gt; years&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: justify"&gt;December 31, 2019&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_98E_ecustom--RiskadjustmentAssessmentOfAchievingMilestone_pid_dp_uPure_c20190101__20191231_ziZWmD8Es4z2" style="text-align: right" title="Risk-adjustment Assessment of achieving each Milestone"&gt;80&lt;/td&gt;&lt;td style="text-align: left"&gt;%&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_981_ecustom--DiscountRatesOnMileStoneLiabilities_pid_dp_uPure_c20190101__20191231_zntDJcXdAr3" style="text-align: right" title="Discount Rate"&gt;9&lt;/td&gt;&lt;td style="text-align: left"&gt;%&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: right"&gt;&lt;span id="xdx_904_ecustom--EstimatedTimeToAchieveMileStone_dtY_c20190101__20191231__srt--RangeAxis__srt--MinimumMember_zYVf3aGllpZ5" title="Estimated time to achieve mile stone"&gt;1.12&lt;/span&gt; to &lt;span id="xdx_900_ecustom--EstimatedTimeToAchieveMileStone_dtY_c20190101__20191231__srt--RangeAxis__srt--MaximumMember_z58MTLigl5zb" title="Estimated time to achieve mile stone"&gt;2.12&lt;/span&gt; years&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;

&lt;p id="xdx_8AF_zjJXIvlblwI8" style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&#160;&lt;/p&gt;




&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;&#160;&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b/&gt;&lt;/span&gt;&lt;/p&gt;

</CLSN:EarnoutMilestoneLiabilityDisclosureTextBlock>
    <CLSN:EarnoutMilestoneLiability1
      contextRef="AsOf2019-03-28_custom_AmendedAssetPurchaseAgreementMember_custom_AchievingMilestoneWithInOneYearMember"
      decimals="-5"
      unitRef="USD">12400000</CLSN:EarnoutMilestoneLiability1>
    <CLSN:EarnoutMilestoneLiability1
      contextRef="AsOf2019-03-28_custom_AmendedAssetPurchaseAgreementMember_custom_CertainBusinessDaysOfAchievingMilestoneMember"
      decimals="-6"
      unitRef="USD">7000000.0</CLSN:EarnoutMilestoneLiability1>
    <CLSN:EarnoutMilestoneLiability1
      contextRef="AsOf2019-03-28_custom_AmendedAssetPurchaseAgreementMember"
      decimals="-5"
      unitRef="USD">12400000</CLSN:EarnoutMilestoneLiability1>
    <us-gaap:BusinessCombinationConsiderationTransferredLiabilitiesIncurred
      contextRef="From2021-01-012021-09-30_custom_EGWCMember_custom_FairValueEarnoutMilestoneLiabilityMember"
      decimals="-5"
      unitRef="USD">7300000</us-gaap:BusinessCombinationConsiderationTransferredLiabilitiesIncurred>
    <us-gaap:BusinessCombinationConsiderationTransferredLiabilitiesIncurred
      contextRef="From2021-01-012021-06-30_custom_EGWCMember_custom_FairValueEarnoutMilestoneLiabilityMember"
      decimals="-5"
      unitRef="USD">7100000</us-gaap:BusinessCombinationConsiderationTransferredLiabilitiesIncurred>
    <us-gaap:BusinessCombinationConsiderationTransferredLiabilitiesIncurred
      contextRef="From2020-01-012020-12-31_custom_EGWCMember_custom_FairValueEarnoutMilestoneLiabilityMember"
      decimals="-6"
      unitRef="USD">7000000.0</us-gaap:BusinessCombinationConsiderationTransferredLiabilitiesIncurred>
    <CLSN:NoncashChargeOnEarnoutMilestoneLiability
      contextRef="From2021-07-012021-09-30_custom_EGWCMember"
      decimals="-5"
      unitRef="USD">300000</CLSN:NoncashChargeOnEarnoutMilestoneLiability>
    <CLSN:NoncashChargeOnEarnoutMilestoneLiability
      contextRef="From2021-01-012021-09-30_custom_EGWCMember"
      decimals="-5"
      unitRef="USD">300000</CLSN:NoncashChargeOnEarnoutMilestoneLiability>
    <CLSN:EarnoutPaymentOptionsDescription contextRef="From2021-01-012021-09-30_custom_EGWCMember">In assessing the earnout milestone liability at September 30, 2021 and June 30, 2021, the Company
determined the fair value of each of the two payment options per the Amended Asset Purchase Agreement and weighted them at 50% and 50%
probability for the $7.0 million and the $12.4 million payments, respectively.</CLSN:EarnoutPaymentOptionsDescription>
    <us-gaap:BusinessCombinationConsiderationTransferredLiabilitiesIncurred
      contextRef="From2020-01-012020-09-30_custom_EGWCMember_custom_FairValueEarnoutMilestoneLiabilityMember"
      decimals="-5"
      unitRef="USD">7100000</us-gaap:BusinessCombinationConsiderationTransferredLiabilitiesIncurred>
    <us-gaap:BusinessCombinationConsiderationTransferredLiabilitiesIncurred
      contextRef="From2020-01-012020-06-30_custom_EGWCMember_custom_FairValueEarnoutMilestoneLiabilityMember"
      decimals="-5"
      unitRef="USD">6000000.0</us-gaap:BusinessCombinationConsiderationTransferredLiabilitiesIncurred>
    <us-gaap:BusinessCombinationConsiderationTransferredLiabilitiesIncurred
      contextRef="From2019-01-012019-12-31_custom_EGWCMember_custom_FairValueEarnoutMilestoneLiabilityMember"
      decimals="-5"
      unitRef="USD">5700000</us-gaap:BusinessCombinationConsiderationTransferredLiabilitiesIncurred>
    <CLSN:NoncashChargeOnEarnoutMilestoneLiability
      contextRef="From2020-07-012020-09-30_custom_EGWCMember"
      decimals="-5"
      unitRef="USD">1100000</CLSN:NoncashChargeOnEarnoutMilestoneLiability>
    <CLSN:NoncashChargeOnEarnoutMilestoneLiability
      contextRef="From2020-01-012020-09-30_custom_EGWCMember"
      decimals="-5"
      unitRef="USD">1400000</CLSN:NoncashChargeOnEarnoutMilestoneLiability>
    <CLSN:EarnoutPaymentOptionsDescription contextRef="From2020-01-012020-09-30_custom_EGWCMember">In assessing the earnout milestone liability at September 30, 2020, the
Company fair valued each of the two payment options per the Amended Asset Purchase Agreement and weighted them at 50% and 50% probability
for the $7.0 million and the $12.4 million payments, respectively, and at June 30, 2020, the Company determined the fair value of each
of the two payment options per the Amended Asset Purchase Agreement and weighted them at 80% and 20% probability for the $7.0 million
and the $12.4 million payments, respectively.</CLSN:EarnoutPaymentOptionsDescription>
    <CLSN:ScheduleOfChangesInEarnOutMilestoneLiabilitiesTableTextBlock contextRef="From2021-01-01to2021-09-30">&lt;p id="xdx_89F_ecustom--ScheduleOfChangesInEarnOutMilestoneLiabilitiesTableTextBlock_z6P8YoyfqFQa" style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;The
following is a summary of the changes in the earn-out milestone liability for the nine-month period ended September 30, 2021:&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;span id="xdx_8BB_zJaNC2oL9zYd" style="display: none"&gt;Schedule of Changes in Earn-out Milestone Liability&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; border-collapse: collapse; width: 100%"&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="width: 80%"&gt;Balance at January 1, 2021&lt;/td&gt;&lt;td style="width: 2%"&gt;&#160;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_98A_ecustom--EarnoutMilestoneLiability_iS_c20210101__20210930_zpcwF9poQBWg" style="width: 16%; text-align: right" title="Earn-out liabilities, beginning balance"&gt;(7,018,000&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;)&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left; padding-bottom: 1.5pt"&gt;Non-cash loss from the change in fair value&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_987_ecustom--GainLossFromChangeInFairValueOfEarnOutMilestoneLiability_c20210101__20210930_pp0p0" style="border-bottom: Black 1.5pt solid; text-align: right" title="Non-cash gain loss from the adjustment for the change in fair value"&gt;(327,000&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;)&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="padding-bottom: 2.5pt"&gt;Balance at September 30, 2021&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_983_ecustom--EarnoutMilestoneLiability_iE_pp0p0_c20210101__20210930_zhHtqewkWQT" style="border-bottom: Black 2.5pt double; text-align: right" title="Earn-out liabilities, ending balance"&gt;(7,345,000&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;)&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;

</CLSN:ScheduleOfChangesInEarnOutMilestoneLiabilitiesTableTextBlock>
    <CLSN:EarnoutMilestoneLiability contextRef="AsOf2020-12-31" decimals="0" unitRef="USD">-7018000</CLSN:EarnoutMilestoneLiability>
    <CLSN:GainLossFromChangeInFairValueOfEarnOutMilestoneLiability
      contextRef="From2021-01-01to2021-09-30"
      decimals="0"
      unitRef="USD">-327000</CLSN:GainLossFromChangeInFairValueOfEarnOutMilestoneLiability>
    <CLSN:EarnoutMilestoneLiability contextRef="AsOf2021-09-30" decimals="0" unitRef="USD">-7345000</CLSN:EarnoutMilestoneLiability>
    <CLSN:ScheduleOfRiskadjustmentAssessmentTableTextBlock contextRef="From2021-01-01to2021-09-30">&lt;p id="xdx_89E_ecustom--ScheduleOfRiskadjustmentAssessmentTableTextBlock_zUkshKqCzlL1" style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;The
following is a schedule of the Company&#x2019;s risk-adjustment assessment of each milestone:&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;span id="xdx_8BB_zEShiugTzqbg" style="display: none"&gt;Schedule of Risk Adjustment Assessment&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"/&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; border-collapse: collapse; width: 100%"&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: center"&gt;Date&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Risk-adjustment Assessment&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;of Achieving Each Milestone&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;Discount Rate&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Estimated Time&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;to Achieve&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td style="text-align: justify"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" style="text-align: center"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" style="text-align: center"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: center"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: justify; width: 36%"&gt;September 30, 2021&lt;/td&gt;&lt;td style="width: 2%"&gt;&#160;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_982_ecustom--RiskadjustmentAssessmentOfAchievingMilestone_pid_dp_uPure_c20210101__20210930_ze0FEABLQXP3" style="width: 18%; text-align: right" title="Risk-adjustment Assessment of achieving each Milestone"&gt;80&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;%&lt;/td&gt;&lt;td style="width: 2%"&gt;&#160;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="width: 18%; text-align: right"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span id="xdx_900_ecustom--DiscountRatesOnMileStoneLiabilities_pid_dp_uPure_c20210101__20210930__srt--RangeAxis__srt--MinimumMember_zDYsFxRz7St2" title="Discount Rate"&gt;6.54&lt;/span&gt;% to &lt;span id="xdx_902_ecustom--DiscountRatesOnMileStoneLiabilities_pid_dp_uPure_c20210101__20210930__srt--RangeAxis__srt--MaximumMember_zwWGBvW0EU4d"&gt;6.60&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;%&lt;/td&gt;&lt;td style="width: 2%"&gt;&#160;&lt;/td&gt;
    &lt;td style="width: 18%; text-align: right"&gt;&lt;span id="xdx_902_ecustom--EstimatedTimeToAchieveMileStone_dtY_c20210101__20210930__srt--RangeAxis__srt--MinimumMember_z9ETKy69Bsmg" title="Estimated time to achieve mile stone"&gt;0.29&lt;/span&gt; to &lt;span id="xdx_90A_ecustom--EstimatedTimeToAchieveMileStone_dtY_c20210101__20210930__srt--RangeAxis__srt--MaximumMember_zlGGuOSofXQ8" title="Estimated time to achieve mile stone"&gt;1.29&lt;/span&gt; years&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: justify"&gt;June 30, 2021&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_98A_ecustom--RiskadjustmentAssessmentOfAchievingMilestone_pid_dp_uPure_c20210101__20210630_zrPOhEHYrI9i" style="text-align: right" title="Risk-adjustment Assessment of achieving each Milestone"&gt;80&lt;/td&gt;&lt;td style="text-align: left"&gt;%&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_98A_ecustom--DiscountRatesOnMileStoneLiabilities_pid_dp_uPure_c20210101__20210630_zrm6J6DLrWzg" style="text-align: right" title="Discount Rate"&gt;9&lt;/td&gt;&lt;td style="text-align: left"&gt;%&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: right"&gt;&lt;span id="xdx_901_ecustom--EstimatedTimeToAchieveMileStone_dtY_c20210101__20210630__srt--RangeAxis__srt--MinimumMember_zF8WoRh5NZa" title="[custom:EstimatedTimeToAchieveMileStone]"&gt;0.42&lt;/span&gt; to &lt;span id="xdx_908_ecustom--EstimatedTimeToAchieveMileStone_dtY_c20210101__20210630__srt--RangeAxis__srt--MaximumMember_zErCy2KQRwkj" title="[custom:EstimatedTimeToAchieveMileStone]"&gt;1.42&lt;/span&gt; years&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: justify"&gt;December 31, 2020&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_98C_ecustom--RiskadjustmentAssessmentOfAchievingMilestone_pid_dp_uPure_c20200101__20201231_z013cfBO3t73" style="text-align: right" title="Risk-adjustment Assessment of achieving each Milestone"&gt;80&lt;/td&gt;&lt;td style="text-align: left"&gt;%&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_98D_ecustom--DiscountRatesOnMileStoneLiabilities_pid_dp_uPure_c20200101__20201231_ztbvNDAT1wj8" style="text-align: right" title="Discount Rate"&gt;9&lt;/td&gt;&lt;td style="text-align: left"&gt;%&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: right"&gt;&lt;span id="xdx_908_ecustom--EstimatedTimeToAchieveMileStone_dtY_c20200101__20201231__srt--RangeAxis__srt--MinimumMember_zix4UkxrlDbg" title="[custom:EstimatedTimeToAchieveMileStone]"&gt;0.54&lt;/span&gt; to &lt;span id="xdx_907_ecustom--EstimatedTimeToAchieveMileStone_dtY_c20200101__20201231__srt--RangeAxis__srt--MaximumMember_zhoB79ftHQUc" title="[custom:EstimatedTimeToAchieveMileStone]"&gt;1.54&lt;/span&gt; years&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: justify"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: justify"&gt;September 30, 2020&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_985_ecustom--RiskadjustmentAssessmentOfAchievingMilestone_pid_dp_uPure_c20200101__20200930_zDqTVXnnzWHk" style="text-align: right" title="Risk-adjustment Assessment of achieving each Milestone"&gt;80&lt;/td&gt;&lt;td style="text-align: left"&gt;%&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_986_ecustom--DiscountRatesOnMileStoneLiabilities_pid_dp_uPure_c20200101__20200930_zZU8o9IPcC1i" style="text-align: right" title="Discount Rate"&gt;9&lt;/td&gt;&lt;td style="text-align: left"&gt;%&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: right"&gt;&lt;span id="xdx_903_ecustom--EstimatedTimeToAchieveMileStone_dtY_c20200101__20200930__srt--RangeAxis__srt--MinimumMember_zDpK3V0UFHMd" title="[custom:EstimatedTimeToAchieveMileStone]"&gt;0.38&lt;/span&gt; to &lt;span id="xdx_90A_ecustom--EstimatedTimeToAchieveMileStone_dtY_c20200101__20200930__srt--RangeAxis__srt--MaximumMember_z8H6RyZWFlb2" title="[custom:EstimatedTimeToAchieveMileStone]"&gt;1.38&lt;/span&gt; years&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: justify"&gt;June 30, 2020&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_982_ecustom--RiskadjustmentAssessmentOfAchievingMilestone_pid_dp_uPure_c20200101__20200630_zfaMBL2p4fM1" style="text-align: right" title="Risk-adjustment Assessment of achieving each Milestone"&gt;80&lt;/td&gt;&lt;td style="text-align: left"&gt;%&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_98E_ecustom--DiscountRatesOnMileStoneLiabilities_pid_dp_uPure_c20200101__20200630_zPYh3VXJkvVg" style="text-align: right" title="Discount Rate"&gt;9&lt;/td&gt;&lt;td style="text-align: left"&gt;%&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: right"&gt;&lt;span id="xdx_90E_ecustom--EstimatedTimeToAchieveMileStone_dtY_c20200101__20200630__srt--RangeAxis__srt--MinimumMember_zKbxtNExTShc" title="[custom:EstimatedTimeToAchieveMileStone]"&gt;0.54&lt;/span&gt; to &lt;span id="xdx_900_ecustom--EstimatedTimeToAchieveMileStone_dtY_c20200101__20200630__srt--RangeAxis__srt--MaximumMember_zFQLKU0EqDn" title="[custom:EstimatedTimeToAchieveMileStone]"&gt;1.54&lt;/span&gt; years&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: justify"&gt;December 31, 2019&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_98E_ecustom--RiskadjustmentAssessmentOfAchievingMilestone_pid_dp_uPure_c20190101__20191231_ziZWmD8Es4z2" style="text-align: right" title="Risk-adjustment Assessment of achieving each Milestone"&gt;80&lt;/td&gt;&lt;td style="text-align: left"&gt;%&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_981_ecustom--DiscountRatesOnMileStoneLiabilities_pid_dp_uPure_c20190101__20191231_zntDJcXdAr3" style="text-align: right" title="Discount Rate"&gt;9&lt;/td&gt;&lt;td style="text-align: left"&gt;%&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: right"&gt;&lt;span id="xdx_904_ecustom--EstimatedTimeToAchieveMileStone_dtY_c20190101__20191231__srt--RangeAxis__srt--MinimumMember_zYVf3aGllpZ5" title="Estimated time to achieve mile stone"&gt;1.12&lt;/span&gt; to &lt;span id="xdx_900_ecustom--EstimatedTimeToAchieveMileStone_dtY_c20190101__20191231__srt--RangeAxis__srt--MaximumMember_z58MTLigl5zb" title="Estimated time to achieve mile stone"&gt;2.12&lt;/span&gt; years&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;

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    <CLSN:WarrantsTextBlock contextRef="From2021-01-01to2021-09-30">&lt;p id="xdx_807_ecustom--WarrantsTextBlock_zA2NKB1o3jPj" style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Note
15. &lt;span id="xdx_82D_zBdde2B9J4ga"&gt;Warrants&lt;/span&gt;&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p id="xdx_89A_eus-gaap--ScheduleOfStockholdersEquityNoteWarrantsOrRightsTextBlock_zdXP9A6bb6p" style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Following
is a summary of all warrant activity for the nine-months ended September 30, 2021:&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;span id="xdx_8BA_zrsSocFl6jn7" style="display: none"&gt;Summary of Warrant Activity&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; border-collapse: collapse; width: 100%"&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td style="border-bottom: Black 1.5pt solid"&gt;Warrants&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Number of&lt;br/&gt; Warrants&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Issued&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Weighted&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Average&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Exercise Price&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="width: 60%; text-align: left"&gt;Warrants outstanding at December 31, 2020&lt;/td&gt;&lt;td style="width: 2%"&gt;&#160;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_986_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingNumber_iS_c20210101__20210930_z803eNLF7w3e" style="width: 16%; text-align: right" title="Number of Warrants Issued, Warrants outstanding, Beginning balance"&gt;3,853,566&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="width: 2%"&gt;&#160;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_981_ecustom--ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingWeightedAverageExercisePrice_iS_c20210101__20210930_zyRe6a1BKKp3" style="width: 16%; text-align: right" title="Weighted Average Exercise Price, Warrants outstanding, Beginning balance"&gt;1.35&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left; padding-bottom: 1.5pt"&gt;Warrants exercised during the nine months ended September 30, 2021 (see Note 12)&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_987_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsExercised_iN_di_c20210101__20210930_zrQyCCwiqic3" style="border-bottom: Black 1.5pt solid; text-align: right" title="Number of Warrants Issued, Warrants exercised"&gt;(1,216,667&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;)&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_98D_ecustom--ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsExerciseInPeriodWeightedAverageExercisePrice_c20210101__20210930_pdd" style="padding-bottom: 1.5pt; text-align: right" title="Weighted Average Exercise Price, Warrants exercised"&gt;1.24&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left; padding-bottom: 2.5pt"&gt;Warrants outstanding at September 30, 2021&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_98D_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingNumber_iE_c20210101__20210930_zjdJBdPPPH7h" style="border-bottom: Black 2.5pt double; text-align: right" title="Number of Warrants Issued, Warrants outstanding, Ending balance"&gt;2,636,899&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_985_ecustom--ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingWeightedAverageExercisePrice_iE_c20210101__20210930_zrMjZrnDYcBh" style="padding-bottom: 2.5pt; text-align: right" title="Weighted Average Exercise Price, Warrants outstanding, Ending balance"&gt;1.40&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left; padding-bottom: 2.5pt"&gt;Aggregate intrinsic value of outstanding warrants at September 30, 2021&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_983_ecustom--ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionsOutstandingIntrinsicValue_c20210930_pp0p0" style="border-bottom: Black 2.5pt double; text-align: right" title="Aggregate intrinsic value of outstanding warrants"&gt;159,857&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left"&gt;Weighted average remaining contractual terms at September 30, 2021&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span id="xdx_90C_ecustom--SharebasedCompensationArrangementBySharebasedPaymentAwardNonOptionsOutstandingWeightedAverageRemainingContractualTerm2_dtY_c20210101__20210930_zyi7L7bhizJc" title="Weighted average remaining contractual terms (years)"&gt;4.1&lt;/span&gt; years&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;


&lt;p id="xdx_8A9_z3Ad73wousG4" style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

</CLSN:WarrantsTextBlock>
    <us-gaap:ScheduleOfStockholdersEquityNoteWarrantsOrRightsTextBlock contextRef="From2021-01-01to2021-09-30">&lt;p id="xdx_89A_eus-gaap--ScheduleOfStockholdersEquityNoteWarrantsOrRightsTextBlock_zdXP9A6bb6p" style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Following
is a summary of all warrant activity for the nine-months ended September 30, 2021:&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;span id="xdx_8BA_zrsSocFl6jn7" style="display: none"&gt;Summary of Warrant Activity&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; border-collapse: collapse; width: 100%"&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td style="border-bottom: Black 1.5pt solid"&gt;Warrants&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Number of&lt;br/&gt; Warrants&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Issued&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Weighted&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Average&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Exercise Price&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="width: 60%; text-align: left"&gt;Warrants outstanding at December 31, 2020&lt;/td&gt;&lt;td style="width: 2%"&gt;&#160;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_986_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingNumber_iS_c20210101__20210930_z803eNLF7w3e" style="width: 16%; text-align: right" title="Number of Warrants Issued, Warrants outstanding, Beginning balance"&gt;3,853,566&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="width: 2%"&gt;&#160;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_981_ecustom--ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingWeightedAverageExercisePrice_iS_c20210101__20210930_zyRe6a1BKKp3" style="width: 16%; text-align: right" title="Weighted Average Exercise Price, Warrants outstanding, Beginning balance"&gt;1.35&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left; padding-bottom: 1.5pt"&gt;Warrants exercised during the nine months ended September 30, 2021 (see Note 12)&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_987_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsExercised_iN_di_c20210101__20210930_zrQyCCwiqic3" style="border-bottom: Black 1.5pt solid; text-align: right" title="Number of Warrants Issued, Warrants exercised"&gt;(1,216,667&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;)&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_98D_ecustom--ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsExerciseInPeriodWeightedAverageExercisePrice_c20210101__20210930_pdd" style="padding-bottom: 1.5pt; text-align: right" title="Weighted Average Exercise Price, Warrants exercised"&gt;1.24&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left; padding-bottom: 2.5pt"&gt;Warrants outstanding at September 30, 2021&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_98D_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingNumber_iE_c20210101__20210930_zjdJBdPPPH7h" style="border-bottom: Black 2.5pt double; text-align: right" title="Number of Warrants Issued, Warrants outstanding, Ending balance"&gt;2,636,899&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_985_ecustom--ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingWeightedAverageExercisePrice_iE_c20210101__20210930_zrMjZrnDYcBh" style="padding-bottom: 2.5pt; text-align: right" title="Weighted Average Exercise Price, Warrants outstanding, Ending balance"&gt;1.40&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left; padding-bottom: 2.5pt"&gt;Aggregate intrinsic value of outstanding warrants at September 30, 2021&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;$&lt;/td&gt;&lt;td id="xdx_983_ecustom--ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionsOutstandingIntrinsicValue_c20210930_pp0p0" style="border-bottom: Black 2.5pt double; text-align: right" title="Aggregate intrinsic value of outstanding warrants"&gt;159,857&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left"&gt;Weighted average remaining contractual terms at September 30, 2021&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span id="xdx_90C_ecustom--SharebasedCompensationArrangementBySharebasedPaymentAwardNonOptionsOutstandingWeightedAverageRemainingContractualTerm2_dtY_c20210101__20210930_zyi7L7bhizJc" title="Weighted average remaining contractual terms (years)"&gt;4.1&lt;/span&gt; years&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;


</us-gaap:ScheduleOfStockholdersEquityNoteWarrantsOrRightsTextBlock>
    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingNumber contextRef="AsOf2020-12-31" decimals="INF" unitRef="Shares">3853566</us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingNumber>
    <CLSN:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingWeightedAverageExercisePrice
      contextRef="AsOf2020-12-31"
      decimals="INF"
      unitRef="USDPShares">1.35</CLSN:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingWeightedAverageExercisePrice>
    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsExercised
      contextRef="From2021-01-01to2021-09-30"
      decimals="INF"
      unitRef="Shares">1216667</us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsExercised>
    <CLSN:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsExerciseInPeriodWeightedAverageExercisePrice
      contextRef="From2021-01-01to2021-09-30"
      decimals="INF"
      unitRef="USDPShares">1.24</CLSN:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsExerciseInPeriodWeightedAverageExercisePrice>
    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingNumber contextRef="AsOf2021-09-30" decimals="INF" unitRef="Shares">2636899</us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingNumber>
    <CLSN:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingWeightedAverageExercisePrice
      contextRef="AsOf2021-09-30"
      decimals="INF"
      unitRef="USDPShares">1.40</CLSN:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingWeightedAverageExercisePrice>
    <CLSN:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionsOutstandingIntrinsicValue contextRef="AsOf2021-09-30" decimals="0" unitRef="USD">159857</CLSN:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionsOutstandingIntrinsicValue>
    <CLSN:SharebasedCompensationArrangementBySharebasedPaymentAwardNonOptionsOutstandingWeightedAverageRemainingContractualTerm2 contextRef="From2021-01-01to2021-09-30">P4Y1M6D</CLSN:SharebasedCompensationArrangementBySharebasedPaymentAwardNonOptionsOutstandingWeightedAverageRemainingContractualTerm2>
    <us-gaap:LesseeOperatingLeasesTextBlock contextRef="From2021-01-01to2021-09-30">&lt;p id="xdx_804_eus-gaap--LesseeOperatingLeasesTextBlock_zdPTKqqaXjUd" style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Note
16. &lt;span id="xdx_828_zp7kWMUOMS05"&gt;Leases&lt;/span&gt;&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span id="xdx_908_eus-gaap--LesseeOperatingLeaseDescription_c20110701__20110731" title="Lessee, Operating Lease, Description"&gt;In
2011, the Company executed a lease (the &#x201c;Lease&#x201d;) with Brandywine Operating Partnership, L.P. (Brandywine), a Delaware limited
partnership, for a &lt;span id="xdx_90E_eus-gaap--AreaOfLand_iI_pid_uSqft_c20110731_z8lXjbOnwl1" title="Area of Land"&gt;10,870&lt;/span&gt; square foot premises located in Lawrenceville, New Jersey and relocated its offices to Lawrenceville, New Jersey
from Columbia, Maryland.&lt;/span&gt; The Lease had an initial term of &lt;span id="xdx_906_eus-gaap--LesseeOperatingLeaseTermOfContract_iI_dtM_c20110731_zz8jAriJ1bZj" title="Lessee, Operating Lease, Term of Contract"&gt;66&lt;/span&gt; months. In late 2015, Lenox Drive Office Park LLC purchased the real estate
and office building and assumed the Lease. This Lease was set to expire on &lt;span id="xdx_906_eus-gaap--LeaseExpirationDate1_dd_c20110701__20110731_zdSTqS7eSU93" title="Lease Expiration Date"&gt;April 30, 2017&lt;/span&gt;. In April 2017, the Company and the landlord
amended the Lease effective May 1, 2017. The 1&lt;sup&gt;st&lt;/sup&gt; Lease Amendment extended the term of the agreement for an additional 64 months,
reduced the premises to 7,565 square feet, reduced the monthly rent and provided four months free rent. The monthly rent ranged from
approximately $&lt;span id="xdx_900_eus-gaap--PaymentsForRent_c20210101__20210930__us-gaap--TypeOfArrangementAxis__custom--FirstLeaseAmendmentMember__us-gaap--AwardTypeAxis__custom--FirstYearMember_pp0p0" title="Payments for Rent"&gt;18,900&lt;/span&gt; in the first year to approximately $&lt;span id="xdx_904_eus-gaap--PaymentsForRent_c20210101__20210930__us-gaap--TypeOfArrangementAxis__custom--FirstLeaseAmendmentMember__us-gaap--AwardTypeAxis__custom--FinalYearMember_pp0p0" title="Payments for Rent"&gt;20,500&lt;/span&gt; in the final year of the 1&lt;sup&gt;st&lt;/sup&gt; Lease Amendment. Effective January
9, 2019, the Company amended the current terms of the 1&lt;sup&gt;st&lt;/sup&gt; Lease Amendment to &lt;span id="xdx_901_eus-gaap--LesseeOperatingLeaseDescription_c20210108__20210109__us-gaap--TypeOfArrangementAxis__custom--FirstLeaseAmendmentMember_zVN1gBUDloh4" title="Operating lease, description"&gt;increase the size of the premises by 2,285 square
feet to 9,850 square feet and also extended the lease term by one year to September 1, 2023&lt;/span&gt;. The monthly rent ranges from approximately
$&lt;span id="xdx_909_eus-gaap--PaymentsForRent_c20210101__20210930__us-gaap--TypeOfArrangementAxis__custom--SecondLeaseAmendmentMember__us-gaap--AwardTypeAxis__custom--FirstYearMember_pp0p0" title="Payments for Rent"&gt;25,035&lt;/span&gt; in the first year to approximately $&lt;span id="xdx_906_eus-gaap--PaymentsForRent_c20210101__20210930__us-gaap--TypeOfArrangementAxis__custom--SecondLeaseAmendmentMember__us-gaap--AwardTypeAxis__custom--FinalYearMember_pp0p0" title="Payments for Rent"&gt;27,088&lt;/span&gt; in the final year of the 2&lt;sup&gt;nd&lt;/sup&gt; Lease Amendment.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span id="xdx_907_eus-gaap--LesseeOperatingLeaseDescription_c20180101__20180131__us-gaap--TypeOfArrangementAxis__custom--EGENAssetPurchaseAgreementMember" title="Lessee, Operating Lease, Description"&gt;In
connection with the EGEN Asset Purchase Agreement in June 2014, the Company assumed the existing lease with another landlord for an &lt;span id="xdx_901_eus-gaap--AreaOfLand_iI_pid_uSqft_c20201231__srt--StatementGeographicalAxis__custom--HuntsvilleAlabamaMember_zaXvbRo3q1J7" title="Area of Land"&gt;11,500&lt;/span&gt;
square foot premises located in Huntsville Alabama.&lt;/span&gt; In January 2018, the Company and the Huntsville landlord entered into a new 60-month
lease which reduced the premises to 9,049 square feet with rent payments of approximately $&lt;span id="xdx_90F_eus-gaap--PaymentsForRent_c20180101__20180131__us-gaap--TypeOfArrangementAxis__custom--EGENAssetPurchaseAgreementMember_pp0p0" title="Payments for Rent"&gt;18,100&lt;/span&gt; per month. On June 9, 2021 and, as
amended on July 7, 2021, the Company and the Huntsville landlord entered into a 22-month lease for an additional &lt;span id="xdx_90C_eus-gaap--AreaOfLand_iI_pid_uSqft_c20210709__srt--StatementGeographicalAxis__custom--HuntsvilleAlabamaMember_zax82PVk1JS"&gt;2,197&lt;/span&gt; square foot premises
with rent payments of approximately $&lt;span id="xdx_908_eus-gaap--PaymentsForRent_pp0p0_c20210708__20210709__us-gaap--TypeOfArrangementAxis__custom--EGENAssetPurchaseAgreementMember_zCHAdZXRYoDj"&gt;5,500&lt;/span&gt; per month.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;We
adopted ASC Topic 842 on January 1, 2019 using the modified retrospective transition method for all lease arrangements at the beginning
of the period of adoption. Results for reporting periods beginning January 1, 2019 are presented under ASC 842, while prior period amounts
were not adjusted and continue to be reported in accordance with our historic accounting under Topic 840, Leases. The standard had a
material impact on our Condensed Consolidated Balance Sheet but had no impact on our condensed consolidated net earnings and cash flows.
The most significant impact of adopting ASC Topic 842 was the recognition of the right-of-use (ROU) asset and lease liabilities for operating
leases, which are presented in the following three-line items on the Consolidated Condensed Balance Sheet: (i) operating lease right-of-use
asset; (ii) current operating lease liabilities; and (iii) operating lease liabilities. Therefore, on date of adoption of ASC Topic 842,
the Company recognized a ROU asset of $&lt;span id="xdx_907_eus-gaap--OperatingLeaseRightOfUseAsset_iI_pn5n6_c20190102__us-gaap--AdjustmentsForNewAccountingPronouncementsAxis__us-gaap--AccountingStandardsUpdate201602Member_zjW1ToOvkzi4" title="Operating Lease, Right-of-Use Asset"&gt;1.4&lt;/span&gt; million, operating lease liabilities, current and non-current collectively, of $&lt;span id="xdx_908_eus-gaap--OperatingLeaseLiability_iI_pn5n6_c20190102__us-gaap--AdjustmentsForNewAccountingPronouncementsAxis__us-gaap--AccountingStandardsUpdate201602Member_zuvZWcwACpi6" title="Operating Lease, Liability"&gt;1.5&lt;/span&gt; million
and reduced other liabilities by approximately $&lt;span id="xdx_905_eus-gaap--OtherLiabilities_iI_pn5n6_c20190102__us-gaap--AdjustmentsForNewAccountingPronouncementsAxis__us-gaap--AccountingStandardsUpdate201602Member_ziUjgWe7odR1" title="Other Liabilities"&gt;0.1&lt;/span&gt; million. We elected the package of practical expedients for leases that commenced
before the effective date of ASC Topic 842 whereby we elected to not reassess the following: (i) whether any expired or existing contracts
contain leases; (ii) the lease classification for any expired or existing leases; and (iii) initial direct costs for any existing leases.
In addition, we have lease agreements with lease and non-lease components, and we have elected the practical expedient for all underlying
asset classes and account for them as a single lease component. We have no finance leases. We determine if an arrangement is a lease
at inception. We have operating leases for office space and research and development facilities. Neither of our leases include options
to renew, however, one contains an option for early termination. We considered the option of early termination in measurement of right-of-use
assets and lease liabilities and we determined it is not reasonably certain to be terminated. In connection with the 2&lt;sup&gt;nd&lt;/sup&gt; Lease
Amendment for the New Jersey office lease in January 2019, the Company considered this as one modified lease and not as two separate
leases. Therefore, in January 2019, the Company determined this lease was an operating lease and remeasured the ROU asset and lease liability.
Therefore, the Company increased the ROU asset and operating lease liabilities by $&lt;span id="xdx_906_eus-gaap--OperatingLeaseRightOfUseAsset_iI_pn5n6_c20190102_zK6lZc80gyRc" title="Operating Lease, Right-of-Use Asset"&gt;0.4&lt;/span&gt; million to $&lt;span id="xdx_90C_eus-gaap--RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability_pn5n6_c20181230__20190102_z4wQp4Kkk85" title="Right-of-Use Asset Obtained in Exchange for Operating Lease Liability"&gt;1.8&lt;/span&gt; million and $&lt;span id="xdx_900_eus-gaap--OperatingLeaseLiability_iI_pn5n6_c20190102_z7gawmKxgbXf" title="Operating Lease, Liability"&gt;1.9&lt;/span&gt; million, respectively.
In connection with the 2021 lease, as amended, the Company determined this lease should be treated as a separate contract. Therefore,
during the third quarter of 2021, the Company increased the ROU assets and operating lease liabilities by $&lt;span id="xdx_903_eus-gaap--OperatingLeaseRightOfUseAsset_iI_pn5n6_c20210930__us-gaap--AdjustmentsForNewAccountingPronouncementsAxis__us-gaap--AccountingStandardsUpdate202101Member_zBey1d2Drqx1" title="Operating Lease, Right-of-Use Asset"&gt;&lt;span id="xdx_906_eus-gaap--OperatingLeaseLiability_iI_pn5n6_c20210930__us-gaap--AdjustmentsForNewAccountingPronouncementsAxis__us-gaap--AccountingStandardsUpdate202101Member_zEhuKipWNE0b" title="Operating Lease, Liability"&gt;0.1&lt;/span&gt;&lt;/span&gt; million.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;



&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"/&gt;&lt;/p&gt;

&lt;p id="xdx_89F_eus-gaap--LesseeOperatingLeaseLiabilityMaturityTableTextBlock_zAZmdh6oAmFg" style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Following
is a table of the lease payments and maturity of our operating lease liabilities as of September 30, 2021:&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;span id="xdx_8B6_zgaA89bNy3r3" style="display: none"&gt;Schedule of Lease Payments and Maturity of Operating Lease Liabilities&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; border-collapse: collapse; width: 100%"&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" id="xdx_499_20210930_zwzlzQw7Eyvl" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;For the&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;year ending&lt;br/&gt; September 30,&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_40B_eus-gaap--LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths_iI_pp0p0_maLOLLPzy9p_zywE2OBcJkBb" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="width: 80%"&gt;Remainder of 2021&lt;/td&gt;&lt;td style="width: 2%"&gt;&#160;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;$&lt;/td&gt;&lt;td style="width: 16%; text-align: right"&gt;149,573&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_400_eus-gaap--LesseeOperatingLeaseLiabilityPaymentsDueYearTwo_iI_pp0p0_maLOLLPzy9p_zLrQ6FrxNarc" style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left"&gt;2022&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;601,495&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_402_eus-gaap--LesseeOperatingLeaseLiabilityPaymentsDueYearThree_iI_pp0p0_maLOLLPzy9p_zZJgokDMg4nc" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left"&gt;2023&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;238,609&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_40E_ecustom--LesseeOperatingLeaseLiabilityPaymentsDueAfterYearThreeAndThereAfter_iI_pp0p0_maLOLLPzy9p_zxQIZzF2IT5i" style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left; padding-bottom: 1.5pt"&gt;2024 and thereafter&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl1613"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="border-bottom: Black 1.5pt solid; text-align: right"&gt;-&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_40C_eus-gaap--LesseeOperatingLeaseLiabilityPaymentsDue_iTI_pp0p0_mtLOLLPzy9p_maOLLz45C_maOLLzlbh_zV3A0mqjsQJ" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left"&gt;Subtotal future lease payments&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;989,677&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_40B_eus-gaap--LesseeOperatingLeaseLiabilityUndiscountedExcessAmount_iNI_pp0p0_di_maOLLz45C_maOLLzlbh_zbyD6foJwWr6" style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="padding-left: 10pt; text-align: left; padding-bottom: 1.5pt"&gt;Less imputed interest&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="border-bottom: Black 1.5pt solid; text-align: right"&gt;(81,895&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;)&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_40E_eus-gaap--OperatingLeaseLiability_iI_pp0p0_zxuITXhzy0Pf" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left; padding-bottom: 1.5pt"&gt;Total lease liabilities&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;$&lt;/td&gt;&lt;td style="border-bottom: Black 1.5pt solid; text-align: right"&gt;907,782&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="padding-bottom: 1.5pt"&gt;Weighted average remaining life&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="border-bottom: Black 1.5pt solid; text-align: right"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span id="xdx_909_eus-gaap--OperatingLeaseWeightedAverageRemainingLeaseTerm1_iI_dtY_c20210930_z3p0oUBnkaJi" title="Operating Lease, Weighted Average Remaining Lease Term"&gt;1.7&lt;/span&gt; years&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="padding-bottom: 2.5pt"&gt;Weighted average discount rate&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_983_eus-gaap--OperatingLeaseWeightedAverageDiscountRatePercent_iI_pid_dp_uPure_c20210930_zSlNM89TqyF1" style="border-bottom: Black 2.5pt double; text-align: right" title="Operating Lease, Weighted Average Discount Rate, Percent"&gt;8.28&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;%&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;

&lt;p id="xdx_8A7_zhChuh3fjWf" style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;For
the three-month and nine-month periods ended September 30, 2021, operating lease expense was $&lt;span id="xdx_90F_eus-gaap--OperatingLeaseCost_c20210701__20210930__us-gaap--TypeOfArrangementAxis__custom--OperatingLeasesMember_pp0p0" title="Operating Lease, Cost"&gt;146,936&lt;/span&gt; and $&lt;span id="xdx_909_eus-gaap--OperatingLeaseCost_c20210101__20210930__us-gaap--TypeOfArrangementAxis__custom--OperatingLeasesMember_pp0p0" title="Operating Lease, Cost"&gt;413,577&lt;/span&gt;, respectively and
cash paid for operating leases included in operating cash flows was $&lt;span id="xdx_900_eus-gaap--OperatingLeasePayments_c20210701__20210930__us-gaap--TypeOfArrangementAxis__custom--OperatingLeasesMember_pp0p0" title="Operating Lease, Payments"&gt;149,115&lt;/span&gt; and $&lt;span id="xdx_906_eus-gaap--OperatingLeasePayments_c20210101__20210930__us-gaap--TypeOfArrangementAxis__custom--OperatingLeasesMember_pp0p0" title="Operating Lease, Payments"&gt;418,696&lt;/span&gt;, respectively. For the three-month and nine-month
periods ended September 30, 2020, operating lease expense was $&lt;span id="xdx_90D_eus-gaap--OperatingLeaseCost_c20200701__20200930__us-gaap--TypeOfArrangementAxis__custom--OperatingLeasesMember_pp0p0" title="Operating Lease, Cost"&gt;130,595&lt;/span&gt; and $&lt;span id="xdx_906_eus-gaap--OperatingLeaseCost_c20200101__20200930__us-gaap--TypeOfArrangementAxis__custom--OperatingLeasesMember_pp0p0" title="Operating Lease, Cost"&gt;391,785&lt;/span&gt;, respectively and cash paid for operating leases
included in operating cash flows was $&lt;span id="xdx_902_eus-gaap--OperatingLeasePayments_c20200701__20200930__us-gaap--TypeOfArrangementAxis__custom--OperatingLeasesMember_pp0p0" title="Operating Lease, Payments"&gt;131,863&lt;/span&gt; and $&lt;span id="xdx_908_eus-gaap--OperatingLeasePayments_c20200101__20200930__us-gaap--TypeOfArrangementAxis__custom--OperatingLeasesMember_pp0p0" title="Operating Lease, Payments"&gt;393,947&lt;/span&gt;, respectively.&lt;/span&gt;&lt;/p&gt;
&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

</us-gaap:LesseeOperatingLeasesTextBlock>
    <us-gaap:LesseeOperatingLeaseDescription contextRef="From2011-07-012011-07-31">In
2011, the Company executed a lease (the &#x201c;Lease&#x201d;) with Brandywine Operating Partnership, L.P. (Brandywine), a Delaware limited
partnership, for a 10,870 square foot premises located in Lawrenceville, New Jersey and relocated its offices to Lawrenceville, New Jersey
from Columbia, Maryland.</us-gaap:LesseeOperatingLeaseDescription>
    <us-gaap:AreaOfLand contextRef="AsOf2011-07-31" decimals="INF" unitRef="Sqft">10870</us-gaap:AreaOfLand>
    <us-gaap:LesseeOperatingLeaseTermOfContract contextRef="AsOf2011-07-31">P66M</us-gaap:LesseeOperatingLeaseTermOfContract>
    <us-gaap:LeaseExpirationDate1 contextRef="From2011-07-012011-07-31">2017-04-30</us-gaap:LeaseExpirationDate1>
    <us-gaap:PaymentsForRent
      contextRef="From2021-01-012021-09-30_custom_FirstLeaseAmendmentMember_custom_FirstYearMember"
      decimals="0"
      unitRef="USD">18900</us-gaap:PaymentsForRent>
    <us-gaap:PaymentsForRent
      contextRef="From2021-01-012021-09-30_custom_FirstLeaseAmendmentMember_custom_FinalYearMember"
      decimals="0"
      unitRef="USD">20500</us-gaap:PaymentsForRent>
    <us-gaap:LesseeOperatingLeaseDescription contextRef="From2021-01-082021-01-09_custom_FirstLeaseAmendmentMember">increase the size of the premises by 2,285 square
feet to 9,850 square feet and also extended the lease term by one year to September 1, 2023</us-gaap:LesseeOperatingLeaseDescription>
    <us-gaap:PaymentsForRent
      contextRef="From2021-01-012021-09-30_custom_SecondLeaseAmendmentMember_custom_FirstYearMember"
      decimals="0"
      unitRef="USD">25035</us-gaap:PaymentsForRent>
    <us-gaap:PaymentsForRent
      contextRef="From2021-01-012021-09-30_custom_SecondLeaseAmendmentMember_custom_FinalYearMember"
      decimals="0"
      unitRef="USD">27088</us-gaap:PaymentsForRent>
    <us-gaap:LesseeOperatingLeaseDescription contextRef="From2018-01-012018-01-31_custom_EGENAssetPurchaseAgreementMember">In
connection with the EGEN Asset Purchase Agreement in June 2014, the Company assumed the existing lease with another landlord for an 11,500
square foot premises located in Huntsville Alabama.</us-gaap:LesseeOperatingLeaseDescription>
    <us-gaap:AreaOfLand
      contextRef="AsOf2020-12-31_custom_HuntsvilleAlabamaMember"
      decimals="INF"
      unitRef="Sqft">11500</us-gaap:AreaOfLand>
    <us-gaap:PaymentsForRent
      contextRef="From2018-01-012018-01-31_custom_EGENAssetPurchaseAgreementMember"
      decimals="0"
      unitRef="USD">18100</us-gaap:PaymentsForRent>
    <us-gaap:AreaOfLand
      contextRef="AsOf2021-07-09_custom_HuntsvilleAlabamaMember"
      decimals="INF"
      unitRef="Sqft">2197</us-gaap:AreaOfLand>
    <us-gaap:PaymentsForRent
      contextRef="From2021-07-082021-07-09_custom_EGENAssetPurchaseAgreementMember"
      decimals="0"
      unitRef="USD">5500</us-gaap:PaymentsForRent>
    <us-gaap:OperatingLeaseRightOfUseAsset
      contextRef="AsOf2019-01-02_us-gaap_AccountingStandardsUpdate201602Member"
      decimals="-5"
      unitRef="USD">1400000</us-gaap:OperatingLeaseRightOfUseAsset>
    <us-gaap:OperatingLeaseLiability
      contextRef="AsOf2019-01-02_us-gaap_AccountingStandardsUpdate201602Member"
      decimals="-5"
      unitRef="USD">1500000</us-gaap:OperatingLeaseLiability>
    <us-gaap:OtherLiabilities
      contextRef="AsOf2019-01-02_us-gaap_AccountingStandardsUpdate201602Member"
      decimals="-5"
      unitRef="USD">100000</us-gaap:OtherLiabilities>
    <us-gaap:OperatingLeaseRightOfUseAsset contextRef="AsOf2019-01-02" decimals="-5" unitRef="USD">400000</us-gaap:OperatingLeaseRightOfUseAsset>
    <us-gaap:RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability
      contextRef="From2018-12-302019-01-02"
      decimals="-5"
      unitRef="USD">1800000</us-gaap:RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability>
    <us-gaap:OperatingLeaseLiability contextRef="AsOf2019-01-02" decimals="-5" unitRef="USD">1900000</us-gaap:OperatingLeaseLiability>
    <us-gaap:OperatingLeaseRightOfUseAsset
      contextRef="AsOf2021-09-30_us-gaap_AccountingStandardsUpdate202101Member"
      decimals="-5"
      unitRef="USD">100000</us-gaap:OperatingLeaseRightOfUseAsset>
    <us-gaap:OperatingLeaseLiability
      contextRef="AsOf2021-09-30_us-gaap_AccountingStandardsUpdate202101Member"
      decimals="-5"
      unitRef="USD">100000</us-gaap:OperatingLeaseLiability>
    <us-gaap:LesseeOperatingLeaseLiabilityMaturityTableTextBlock contextRef="From2021-01-01to2021-09-30">&lt;p id="xdx_89F_eus-gaap--LesseeOperatingLeaseLiabilityMaturityTableTextBlock_zAZmdh6oAmFg" style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Following
is a table of the lease payments and maturity of our operating lease liabilities as of September 30, 2021:&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;span id="xdx_8B6_zgaA89bNy3r3" style="display: none"&gt;Schedule of Lease Payments and Maturity of Operating Lease Liabilities&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; border-collapse: collapse; width: 100%"&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td&gt;&#160;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td colspan="2" id="xdx_499_20210930_zwzlzQw7Eyvl" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;For the&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;year ending&lt;br/&gt; September 30,&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_40B_eus-gaap--LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths_iI_pp0p0_maLOLLPzy9p_zywE2OBcJkBb" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="width: 80%"&gt;Remainder of 2021&lt;/td&gt;&lt;td style="width: 2%"&gt;&#160;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;$&lt;/td&gt;&lt;td style="width: 16%; text-align: right"&gt;149,573&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_400_eus-gaap--LesseeOperatingLeaseLiabilityPaymentsDueYearTwo_iI_pp0p0_maLOLLPzy9p_zLrQ6FrxNarc" style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left"&gt;2022&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;601,495&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_402_eus-gaap--LesseeOperatingLeaseLiabilityPaymentsDueYearThree_iI_pp0p0_maLOLLPzy9p_zZJgokDMg4nc" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left"&gt;2023&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;238,609&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_40E_ecustom--LesseeOperatingLeaseLiabilityPaymentsDueAfterYearThreeAndThereAfter_iI_pp0p0_maLOLLPzy9p_zxQIZzF2IT5i" style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left; padding-bottom: 1.5pt"&gt;2024 and thereafter&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl1613"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="border-bottom: Black 1.5pt solid; text-align: right"&gt;-&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_40C_eus-gaap--LesseeOperatingLeaseLiabilityPaymentsDue_iTI_pp0p0_mtLOLLPzy9p_maOLLz45C_maOLLzlbh_zV3A0mqjsQJ" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left"&gt;Subtotal future lease payments&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;989,677&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_40B_eus-gaap--LesseeOperatingLeaseLiabilityUndiscountedExcessAmount_iNI_pp0p0_di_maOLLz45C_maOLLzlbh_zbyD6foJwWr6" style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="padding-left: 10pt; text-align: left; padding-bottom: 1.5pt"&gt;Less imputed interest&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="border-bottom: Black 1.5pt solid; text-align: right"&gt;(81,895&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;)&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_40E_eus-gaap--OperatingLeaseLiability_iI_pp0p0_zxuITXhzy0Pf" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left; padding-bottom: 1.5pt"&gt;Total lease liabilities&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;$&lt;/td&gt;&lt;td style="border-bottom: Black 1.5pt solid; text-align: right"&gt;907,782&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="padding-bottom: 1.5pt"&gt;Weighted average remaining life&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="border-bottom: Black 1.5pt solid; text-align: right"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span id="xdx_909_eus-gaap--OperatingLeaseWeightedAverageRemainingLeaseTerm1_iI_dtY_c20210930_z3p0oUBnkaJi" title="Operating Lease, Weighted Average Remaining Lease Term"&gt;1.7&lt;/span&gt; years&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td&gt;&#160;&lt;/td&gt;&lt;td&gt;&#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;&#160;&lt;/td&gt;&lt;td style="text-align: left"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="padding-bottom: 2.5pt"&gt;Weighted average discount rate&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&#160;&lt;/td&gt;&lt;td id="xdx_983_eus-gaap--OperatingLeaseWeightedAverageDiscountRatePercent_iI_pid_dp_uPure_c20210930_zSlNM89TqyF1" style="border-bottom: Black 2.5pt double; text-align: right" title="Operating Lease, Weighted Average Discount Rate, Percent"&gt;8.28&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;%&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;

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    <us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearTwo contextRef="AsOf2021-09-30" decimals="0" unitRef="USD">601495</us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearTwo>
    <us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearThree contextRef="AsOf2021-09-30" decimals="0" unitRef="USD">238609</us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearThree>
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    <us-gaap:OperatingLeaseLiability contextRef="AsOf2021-09-30" decimals="0" unitRef="USD">907782</us-gaap:OperatingLeaseLiability>
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      unitRef="USD">146936</us-gaap:OperatingLeaseCost>
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      contextRef="From2021-01-012021-09-30_custom_OperatingLeasesMember"
      decimals="0"
      unitRef="USD">413577</us-gaap:OperatingLeaseCost>
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      contextRef="From2021-07-012021-09-30_custom_OperatingLeasesMember"
      decimals="0"
      unitRef="USD">149115</us-gaap:OperatingLeasePayments>
    <us-gaap:OperatingLeasePayments
      contextRef="From2021-01-012021-09-30_custom_OperatingLeasesMember"
      decimals="0"
      unitRef="USD">418696</us-gaap:OperatingLeasePayments>
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      contextRef="From2020-07-012020-09-30_custom_OperatingLeasesMember"
      decimals="0"
      unitRef="USD">130595</us-gaap:OperatingLeaseCost>
    <us-gaap:OperatingLeaseCost
      contextRef="From2020-01-012020-09-30_custom_OperatingLeasesMember"
      decimals="0"
      unitRef="USD">391785</us-gaap:OperatingLeaseCost>
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      contextRef="From2020-07-012020-09-30_custom_OperatingLeasesMember"
      decimals="0"
      unitRef="USD">131863</us-gaap:OperatingLeasePayments>
    <us-gaap:OperatingLeasePayments
      contextRef="From2020-01-012020-09-30_custom_OperatingLeasesMember"
      decimals="0"
      unitRef="USD">393947</us-gaap:OperatingLeasePayments>
    <CLSN:LicensingTransactionTextBlock contextRef="From2021-01-01to2021-09-30">&lt;p id="xdx_805_ecustom--LicensingTransactionTextBlock_zdkfZ9SW3Ifj" style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Note
17. &lt;span id="xdx_821_zqsDigN3LzJc"&gt;Technology Development and Licensing Agreements&lt;/span&gt;&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;On
May 7, 2012, the Company entered into a long-term commercial supply agreement with Zhejiang Hisun Pharmaceutical Co. Ltd. (Hisun) for
the production of ThermoDox&lt;sup&gt;&#xae;&lt;/sup&gt; in the China territory. In accordance with the terms of the agreement, Hisun will be responsible
for providing all of the technical and regulatory support services, including the costs of all technical transfer, registration and bioequivalence
studies, technical transfer costs, Celsion consultative support costs and the purchase of any necessary equipment and additional facility
costs necessary to support capacity requirements for the manufacture of ThermoDox&lt;sup&gt;&#xae;&lt;/sup&gt;. Celsion will repay Hisun for the aggregate
amount of these development costs and fees commencing on the successful completion of three registration batches of ThermoDox&lt;sup&gt;&#xae;&lt;/sup&gt;.
Hisun is also obligated to certain performance requirements under the agreement. The agreement will initially be limited to a percentage
of the production requirements of ThermoDox&lt;sup&gt;&#xae;&lt;/sup&gt; in the China territory with Hisun retaining an option for additional global
supply after local regulatory approval in the China territory. In addition, Hisun will collaborate with Celsion around the regulatory
approval activities for ThermoDox&lt;sup&gt;&#xae; &lt;/sup&gt;with the China State Food and Drug Administration (CHINA FDA). During the first quarter
of 2015, Hisun completed the successful manufacture of three registration batches of ThermoDox&lt;sup&gt;&#xae;&lt;/sup&gt;.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;On
January 18, 2013, we entered into a technology development contract with Hisun, pursuant to which Hisun paid us a non-refundable research
and development fee of $&lt;span id="xdx_906_eus-gaap--ProceedsFromLicenseFeesReceived_pn6n6_c20130117__20130118__us-gaap--AccountsNotesLoansAndFinancingReceivablesByLegalEntityOfCounterpartyTypeAxis__custom--HisunMember_z1hWjfBgGaFj" title="Proceeds from License Fees Received"&gt;5&lt;/span&gt; million to support our development of ThermoDox&lt;sup&gt;&#xae; &lt;/sup&gt;in mainland China, Hong Kong and Macau (the
China territory). Following our announcement on January 31, 2013 that the HEAT study failed to meet its primary endpoint, Celsion and
Hisun have agreed that the Technology Development Contract entered into on January 18, 2013 will remain in effect while the parties continue
to collaborate and are evaluating the next steps in relation to ThermoDox&lt;sup&gt;&#xae;&lt;/sup&gt;, which include the sub-group analysis of patients
in the Phase III HEAT Study for the hepatocellular carcinoma clinical indication and other activities to further the development of ThermoDox&lt;sup&gt;&#xae;
&lt;/sup&gt;for the Greater China market. The $&lt;span id="xdx_90A_eus-gaap--DeferredRevenue_iI_pn5n6_c20130118__us-gaap--AccountsNotesLoansAndFinancingReceivablesByLegalEntityOfCounterpartyTypeAxis__custom--HisunMember_z95Sdn4mWUH3" title="Deferred Revenue"&gt;5.0&lt;/span&gt; million received as a non-refundable payment from Hisun in the first quarter 2013 has been
recorded to deferred revenue and will continue to be amortized over the &lt;span id="xdx_90D_ecustom--DeferredRevenueAmortizationPeriod_dtY_c20130117__20130118__us-gaap--AccountsNotesLoansAndFinancingReceivablesByLegalEntityOfCounterpartyTypeAxis__custom--HisunMember_zjzvDtAayyb5" title="Deferred revenue amortization period"&gt;10&lt;/span&gt; -year term of the agreement, until such time as the parties
find a mutually acceptable path forward on the development of ThermoDox&lt;sup&gt;&#xae;&lt;/sup&gt; based on findings of the ongoing post-study analysis
of the HEAT Study data.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;On
July 19, 2013, the Company and Hisun entered into a Memorandum of Understanding to pursue ongoing cooperation for the continued clinical
development of ThermoDox&lt;sup&gt;&#xae;&lt;/sup&gt; as well as the technology transfer relating to the commercial manufacture of ThermoDox&lt;sup&gt;&#xae;
&lt;/sup&gt;for the China territory. This expanded level of cooperation includes development of the next generation liposomal formulation with
the goal of creating safer, more efficacious versions of marketed cancer chemotherapeutics.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;




&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Among
the key provisions of the Celsion-Hisun Memorandum of Understanding are:&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; width: 100%; border-collapse: collapse"&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: top"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; width: 0.5in; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;&#x25cf;&lt;/b&gt;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Hisun
    will provide the Company with internal resources necessary to complete the technology transfer of the Company&#x2019;s proprietary
    manufacturing process and the production of registration batches for the China territory;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: top"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: top"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;&#x25cf;&lt;/b&gt;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Hisun
    will coordinate with the Company around the clinical and regulatory approval activities for ThermoDox&lt;sup&gt;&#xae;&lt;/sup&gt; as well as
    other liposomal formations with the CHINA FDA; and&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: top"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: top"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;&#x25cf;&lt;/b&gt;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Hisun
    will be granted a right of &lt;i&gt;first&lt;/i&gt; offer for a commercial license to ThermoDox&lt;sup&gt;&#xae;&lt;/sup&gt; for the sale and distribution
    of ThermoDox&lt;sup&gt;&#xae; &lt;/sup&gt;in the China territory.&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;
&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;On
August 8, 2016, we signed a Technology Transfer, Manufacturing and Commercial Supply Agreement (&#x201c;GEN-1 Agreement&#x201d;) with Hisun
to pursue an expanded partnership for the technology transfer relating to the clinical and commercial manufacture and supply of GEN-1,
Celsion&#x2019;s proprietary gene mediated, IL-12 immunotherapy, for the greater China territory, with the option to expand into other
countries in the rest of the world after all necessary regulatory approvals are in effect. The GEN-1 Agreement will help to support supply
for both ongoing and planned clinical studies in the U.S., and for potential future studies of GEN-1 in China. GEN-1 is currently being
evaluated by Celsion in first line ovarian cancer patients.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Key
provisions of the GEN-1 Agreement are as follows:&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0 0pt 9.9pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; width: 100%; border-collapse: collapse"&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: top"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; width: 0.5in"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;&#x25cf;&lt;/b&gt;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;the
    GEN-1 Agreement has targeted unit costs for clinical supplies of GEN-1 that are substantially competitive with the Company&#x2019;s
    current suppliers;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: top"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: top"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;&#x25cf;&lt;/b&gt;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;once
    approved, the cost structure for GEN-1 will support rapid market adoption and significant gross margins across global markets;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: top"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: top"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;&#x25cf;&lt;/b&gt;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Celsion
    will provide Hisun a certain percentage of China&#x2019;s commercial unit demand, and separately of global commercial unit demand,
    subject to regulatory approval;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: top"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: top"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;&#x25cf;&lt;/b&gt;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Hisun
    and Celsion will commence technology transfer activities relating to the manufacture of GEN-1, including all studies required by
    CHINA FDA for site approval; and&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: top"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: top"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;&#x25cf;&lt;/b&gt;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Hisun
    will collaborate with Celsion around the regulatory approval activities for GEN-1 with the CHINA FDA. A local China partner affords
    Celsion access to accelerated CHINA FDA review and potential regulatory exclusivity for the approved indication.&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;
&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;The
Company evaluated the Hisun arrangement in accordance with ASC 606 and determined that its performance obligations under the agreement
include the non-exclusive, royalty-free license, research and development services to be provided by the Company, and its obligation
to serve on a joint committee. The Company concluded that the license was not distinct since its value is closely tied to the ongoing
research and development activities. As such, the license and the research and development services are bundled as a single performance
obligation. Since the provision of the license and research and development services are considered a single performance obligation,
the $&lt;span id="xdx_900_ecustom--UpfrontPaymentBeingRecognized_pp0p0_c20210101__20210930_zB8iZorhD5xe" title="Upfront payment being recognized"&gt;5,000,000&lt;/span&gt; upfront payment is being recognized as revenue ratably through 2022.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

</CLSN:LicensingTransactionTextBlock>
    <us-gaap:ProceedsFromLicenseFeesReceived
      contextRef="From2013-01-172013-01-18_custom_HisunMember"
      decimals="-6"
      unitRef="USD">5000000</us-gaap:ProceedsFromLicenseFeesReceived>
    <us-gaap:DeferredRevenue
      contextRef="AsOf2013-01-18_custom_HisunMember"
      decimals="-5"
      unitRef="USD">5000000.0</us-gaap:DeferredRevenue>
    <CLSN:DeferredRevenueAmortizationPeriod contextRef="From2013-01-172013-01-18_custom_HisunMember">P10Y</CLSN:DeferredRevenueAmortizationPeriod>
    <CLSN:UpfrontPaymentBeingRecognized
      contextRef="From2021-01-01to2021-09-30"
      decimals="0"
      unitRef="USD">5000000</CLSN:UpfrontPaymentBeingRecognized>
    <us-gaap:CommitmentsAndContingenciesDisclosureTextBlock contextRef="From2021-01-01to2021-09-30">&lt;p id="xdx_802_eus-gaap--CommitmentsAndContingenciesDisclosureTextBlock_zuHrNCvSC878" style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Note
18. &lt;span id="xdx_820_zkRZmcmQeL3d"&gt;Commitments and Contingencies&lt;/span&gt;&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;On
September 20, 2019, a purported stockholder of the Company filed a derivative and putative class action lawsuit against the Company and
certain officers and directors (the &#x201c;Shareholder Action&#x201d;). The Company was a defendant in this derivative and putative class
action lawsuit in the Superior Court of New Jersey, Chancery Division, filed by a shareholder against the Company (as both a class action
defendant and nominal defendant), and certain of its officers and directors (the &#x201c;Individual Defendants&#x201d;), with the caption
&lt;i&gt;O&#x2019;Connor v. Braun et al., Docket No. MER-C-000068-19&lt;/i&gt; (the &#x201c;Shareholder Action&#x201d;). The Shareholder Action alleged
breaches of the defendants&#x2019; fiduciary duties based on allegations that the defendants omitted or made improper statements when
seeking shareholder approval of the 2018 Stock Incentive Plan. The Shareholder Action sought, among other things, any damages sustained
by the Company as a result of the defendants&#x2019; alleged wrongdoing, a declaratory judgment against all defendants invalidating the
2018 Stock Incentive Plan and declaring any awards made under the Plan invalid, rescinded, and subject to disgorgement, an order disgorging
the equity awards granted to the Individual Defendants under the 2018 Stock Incentive Plan, and attorneys&#x2019; fees and costs.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;




&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"/&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;On
April 24, 2020, the Company, the Individual Defendants, and the plaintiff (the &#x201c;Parties&#x201d;) entered into a Settlement Agreement
and Release (the &#x201c;Settlement Agreement&#x201d;), which memorializes the terms of the Parties&#x2019; settlement of the Shareholder
Action (the &#x201c;Settlement&#x201d;). The Settlement calls for repricing of certain stock options and payment of plaintiff legal fees
of $&lt;span id="xdx_90B_eus-gaap--LitigationSettlementExpense_c20200422__20200424_pp0p0" title="Litigation Settlement, Expense"&gt;187,500&lt;/span&gt;. On July 24, 2020, the Court issued an order approving the Parties&#x2019; proposed form of notice to shareholders regarding
the Settlement. A hearing was held on September 8, 2020 whereby the Court issued a final approval approving the Settlement. Pursuant
to the Settlement, the Company paid $&lt;span id="xdx_907_eus-gaap--PaymentsForLegalSettlements_pp0p0_c20201001__20201002_zEVD67RNInF9" title="Payments for Legal Settlements"&gt;187,500&lt;/span&gt; on October 1, 2020. Without admitting the validity of any of the claims asserted in the
Shareholder Action, or any liability with respect thereto, and expressly denying all allegations of wrongdoing, fault, liability, or
damage against the Company and the Individual Defendants arising out of any of the conduct, statements, acts or omissions alleged, or
that could have been alleged, in the Shareholder Action, the Company and the Individual Defendants concluded that it was desirable that
the claims be settled on the terms and subject to the conditions set forth in the Settlement Agreement. The Company and the Individual
Defendants entered into the Settlement Agreement for settlement purposes only and solely to avoid the cost and disruption of further
litigation.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;On
October 29, 2020, a putative securities class action was filed against the Company and certain of its officers and directors (the &#x201c;Spar
Individual Defendants&#x201d;) in the U.S. District Court for the District of New Jersey, captioned &lt;i&gt;Spar v. Celsion Corporation, et
al.&lt;/i&gt;, Case No. 1:20-cv-15228. The plaintiff alleges that the Company and Individual Defendants made false and misleading statements
regarding one of the Company&#x2019;s product candidates, ThermoDox&lt;sup&gt;&#xae;&lt;/sup&gt;, and brings claims for damages under Section 10(b)
of the Exchange Act and Rule 10b-5 promulgated thereunder against all Defendants, and under Section 20(a) of the Exchange Act of 1934
against the Spar Individual Defendants. The Company believes that the case is without merit and intends to defend it vigorously. Due
to the early stage of the case neither the likelihood that a loss, if any, will be realized, nor an estimate of possible loss or range
of loss, if any, can be determined.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;In
February 2021, a derivative shareholder lawsuit was filed against the Company, as the nominal defendant, and certain of its directors
and officers as defendants in the U.S. District Court for the District of New Jersey, captioned &lt;i&gt;Fidler v. Michael H. Tardugno et al.&lt;/i&gt;,
Case No. 3:21-cv-02662. The plaintiff alleges breach of fiduciary duty and other claims arising out of alleged statements made by certain
of the Company&#x2019;s directors and/or officers regarding ThermoDox&lt;sup&gt;&#xae;.&lt;/sup&gt; The Company believes it has meritorious defenses
to these claims and intends to vigorously contest this suit. Due to the early stage of the case neither the likelihood that a loss, if
any, will be realized, nor an estimate of possible loss or range of loss, if any, can be determined.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;In
August of 2021, a complaint regarding a corporate books and records demand was filed against the Company in the Court of Chancery of
the State of Delaware, captioned &lt;i&gt;Pacheco v. Celsion Corporation&lt;/i&gt;, Case No. 2021-0705. The plaintiff alleges he is entitled to inspect
the Company&#x2019;s books and records concerning the OPTIMA Study and other materials. The Company believes that the scope of the demand
is without merit and intends to defend it vigorously. Due to the early stage of the case neither the likelihood that a loss, if any,
will be realized, nor an estimate of possible loss or range of loss, if any, can be determined.&lt;/span&gt;&lt;/p&gt;

</us-gaap:CommitmentsAndContingenciesDisclosureTextBlock>
    <us-gaap:LitigationSettlementExpense
      contextRef="From2020-04-222020-04-24"
      decimals="0"
      unitRef="USD">187500</us-gaap:LitigationSettlementExpense>
    <us-gaap:PaymentsForLegalSettlements
      contextRef="From2020-10-012020-10-02"
      decimals="0"
      unitRef="USD">187500</us-gaap:PaymentsForLegalSettlements>
</xbrl>
