<SEC-DOCUMENT>0001104659-22-115117.txt : 20221107
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<ACCEPTANCE-DATETIME>20221107071038
ACCESSION NUMBER:		0001104659-22-115117
CONFORMED SUBMISSION TYPE:	8-K
PUBLIC DOCUMENT COUNT:		13
CONFORMED PERIOD OF REPORT:	20221107
ITEM INFORMATION:		Results of Operations and Financial Condition
ITEM INFORMATION:		Financial Statements and Exhibits
FILED AS OF DATE:		20221107
DATE AS OF CHANGE:		20221107

FILER:

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Mersana Therapeutics, Inc.
		CENTRAL INDEX KEY:			0001442836
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		IRS NUMBER:				000000000
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		8-K
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-38129
		FILM NUMBER:		221363696

	BUSINESS ADDRESS:	
		STREET 1:		840 MEMORIAL DRIVE
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02139
		BUSINESS PHONE:		617-498-0020

	MAIL ADDRESS:	
		STREET 1:		840 MEMORIAL DRIVE
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02139

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	MERSANA THERAPEUTICS INC
		DATE OF NAME CHANGE:	20080813
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<p style="margin: 0; font-size: 10pt"><span style="font: 10pt Times New Roman, Times, Serif">&#160;</span></p>

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"></p>

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

<p style="font: 18pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center"><b>UNITED STATES</b></p>

<p style="font: 18pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center"><b>SECURITIES AND EXCHANGE COMMISSION</b></p>

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center"><b>Washington, D.C. 20549</b></p>

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center">&#160;</p>

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center"></p>

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<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center">&#160;</p>

<p style="font: 18pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center"><b>FORM <span id="xdx_907_edei--DocumentType_c20221107__20221107_zbkR0o0JBlgl"><ix:nonNumeric contextRef="From2022-11-07to2022-11-07" name="dei:DocumentType">8-K</ix:nonNumeric></span></b></p>

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center">&#160;</p>

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center"></p>

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<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center">&#160;</p>

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center"><b>CURRENT REPORT</b></p>

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center"><b>Pursuant to Section 13 or 15(d) <br />
of the
Securities Exchange Act of 1934</b></p>

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center">&#160;</p>

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center">Date of Report (Date of earliest event reported): <b><span id="xdx_905_edei--DocumentPeriodEndDate_c20221107__20221107_ziAswqgbRwlh"><ix:nonNumeric contextRef="From2022-11-07to2022-11-07" format="ixt:datemonthdayyearen" name="dei:DocumentPeriodEndDate">November 7, 2022</ix:nonNumeric></span></b></p>

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center">&#160;</p>

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center"></p>



<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center"></p>

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<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center">&#160;</p>

<p style="font: 18pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center"><b><span id="xdx_909_edei--EntityRegistrantName_c20221107__20221107_zxPZE18HNWMf"><ix:nonNumeric contextRef="From2022-11-07to2022-11-07" name="dei:EntityRegistrantName">MERSANA THERAPEUTICS, INC.</ix:nonNumeric></span></b></p>

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center"><b>(Exact name of registrant as specified in its
charter)</b></p>

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center">&#160;</p>

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center"></p>



<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center"></p>

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<td style="vertical-align: top; text-align: center"><b>(State or other jurisdiction of<br /> incorporation) </b></td>
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<td style="vertical-align: top; text-align: center"><p style="text-align: center; margin-top: 0; margin-bottom: 0"><span style="font-family: Times New Roman, Times, Serif; font-size: 10pt"><b>(Commission</b></span></p>
                                                    <p style="text-align: center; margin-top: 0; margin-bottom: 0"><span style="font-family: Times New Roman, Times, Serif; font-size: 10pt"><b>File Number) &#160;</b></span></p></td>
<td style="text-align: center"><b>&#160;</b></td>
<td style="vertical-align: top; text-align: center"><p style="margin-top: 0; margin-bottom: 0"><span style="font-family: Times New Roman, Times, Serif; font-size: 10pt"><b>(IRS Employer</b></span></p>
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<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center">&#160;</p>

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<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center">&#160;</p>

<p style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; text-align: center">Registrant's telephone number, including
area code: <b>(<span id="xdx_906_edei--CityAreaCode_c20221107__20221107_zegweNyhUp79"><ix:nonNumeric contextRef="From2022-11-07to2022-11-07" name="dei:CityAreaCode">617</ix:nonNumeric></span>) <span id="xdx_905_edei--LocalPhoneNumber_c20221107__20221107_zm1LFVxDZbSf"><ix:nonNumeric contextRef="From2022-11-07to2022-11-07" name="dei:LocalPhoneNumber">498-0020</ix:nonNumeric></span></b></p>

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center">&#160;</p>

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center"><b>Not Applicable</b></p>

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center">(Former name or former address, if changed since
last report)</p>

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center">&#160;</p>

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: left">Check the appropriate box below if the Form 8-K filing is intended
to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (<span style="text-decoration: underline">see</span> General Instruction A.2. below):</p>

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

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0 0pt 0.25in; text-indent: -0.25in"><span style="font-family: Wingdings"><span id="xdx_901_edei--WrittenCommunications_c20221107__20221107_zRWSnPYg1b91"><ix:nonNumeric contextRef="From2022-11-07to2022-11-07" format="ixt:booleanfalse" name="dei:WrittenCommunications">&#168;</ix:nonNumeric></span></span><span style="font-family: Times New Roman, Times, Serif">&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;Written
communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)</span></p>

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0 0pt 0.25in; text-indent: -0.25in"></p>

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0 0pt 0.25in; text-indent: -0.25in"><span style="font-family: Wingdings"><span id="xdx_90E_edei--SolicitingMaterial_c20221107__20221107_z99cfwXsM5P"><ix:nonNumeric contextRef="From2022-11-07to2022-11-07" format="ixt:booleanfalse" name="dei:SolicitingMaterial">&#168;</ix:nonNumeric></span></span><span style="font-family: Times New Roman, Times, Serif">&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;Soliciting
material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)</span></p>

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0 0pt 0.25in; text-indent: -0.25in"></p>

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0 0pt 0.25in; text-indent: -0.25in"><span style="font-family: Wingdings"><span id="xdx_906_edei--PreCommencementTenderOffer_c20221107__20221107_zu7SR6zH1sJ"><ix:nonNumeric contextRef="From2022-11-07to2022-11-07" format="ixt:booleanfalse" name="dei:PreCommencementTenderOffer">&#168;</ix:nonNumeric></span></span><span style="font-family: Times New Roman, Times, Serif">&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;Pre-commencement
communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))</span></p>

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0 0pt 0.25in; text-indent: -0.25in"></p>

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0 0pt 0.25in; text-indent: -0.25in"><span style="font-family: Wingdings"><span id="xdx_906_edei--PreCommencementIssuerTenderOffer_c20221107__20221107_zvCD4XweN5Eb"><ix:nonNumeric contextRef="From2022-11-07to2022-11-07" format="ixt:booleanfalse" name="dei:PreCommencementIssuerTenderOffer">&#168;</ix:nonNumeric></span></span><span style="font-family: Times New Roman, Times, Serif">&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;Pre-commencement
communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))</span></p>

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

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; color: #221E1F">Securities registered pursuant to Section 12(b)
of the Act:</p>

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; color: #221E1F">&#160;</p>

<table cellspacing="0" cellpadding="0" style="font: 10pt Times New Roman, Times, Serif; width: 100%; border-collapse: collapse">
<tr style="text-align: center; vertical-align: bottom">
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<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">&#160;</p>

<p style="font: 10pt Times New Roman, Times, Serif; text-align: left; margin-top: 0pt; margin-right: 0; margin-bottom: 0pt">Indicate by check mark whether the registrant is an emerging growth
company as defined in Rule 405 of the Securities Act of 1933 (&#167;230.405 of this chapter) or Rule 12b-2 of the Securities Exchange
Act of 1934 (&#167;240.12b-2 of this chapter).</p>

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

<p style="font: 10pt Times New Roman, Times, Serif; text-align: left; margin-top: 0pt; margin-right: 0; margin-bottom: 0pt"><span style="font-family: Times New Roman, Times, Serif">Emerging growth company </span><span style="font-family: Wingdings"><span id="xdx_906_edei--EntityEmergingGrowthCompany_c20221107__20221107_zy4LiAkV6rtl"><ix:nonNumeric contextRef="From2022-11-07to2022-11-07" format="ixt:booleanfalse" name="dei:EntityEmergingGrowthCompany">&#168;</ix:nonNumeric></span></span></p>

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

<p style="font: 10pt Times New Roman, Times, Serif; text-align: left; margin-top: 0pt; margin-right: 0; margin-bottom: 0pt"><span style="font-family: Times New Roman, Times, Serif">If an emerging
growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any
new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. <span style="font-family: Wingdings">&#168;</span><span style="font-family: Wingdings"></span></span></p>

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

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"></p>

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

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<td style="width: 10%"><b>Item 2.02</b></td><td style="text-align: justify; width: 90%"><b>Results of Operations and Financial Condition.</b></td></tr></table>

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

<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: left; text-indent: 0.5in; background-color: white">On
November 7, 2022, Mersana Therapeutics, Inc. (the &#8220;Company&#8221;) issued a press release announcing business updates and financial
results for the fiscal quarter ended September 30, 2022. A copy of the press release is being furnished as Exhibit 99.1 to this Current
Report on Form 8-K.</p>

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<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: left; text-indent: 0.5in; background-color: white">The
information contained in Item 2.02 in this Current Report on Form 8-K (including Exhibit 99.1) shall not be deemed &#8220;filed&#8221;
for purposes of Section 18 of the Securities Exchange Act of 1934 (the &#8220;Exchange Act&#8221;) or otherwise subject to the liabilities
of that section, nor shall it be deemed incorporated by reference in any filing under the Securities Act of 1933 or the Exchange Act,
except as expressly set forth by specific reference in such a filing.</p>

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<td style="width: 10%"><b>Item&#160;9.01.</b></td><td style="width: 90%"><b>Financial Statements and Exhibits.</b></td></tr></table>

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<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">(d)&#160;Exhibits</p>

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<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center"><b>SIGNATURES</b></p>

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<p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: left">Pursuant to the requirements of the Securities Exchange Act of 1934,
the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.</p>

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    <td style="width: 5%">&#160;</td>
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    <td><span style="font-size: 10pt">Date: November 7, 2022</span></td>
    <td style="vertical-align: bottom"><span style="font-family: Times New Roman, Times, Serif; font-size: 10pt">By:</span></td>
    <td style="border-bottom: black 1pt solid; vertical-align: bottom"><span style="font-family: Times New Roman, Times, Serif; font-size: 10pt">/s/ Brian DeSchuytner</span></td></tr>
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<P STYLE="text-align: right; margin: 0"><B>Exhibit 99.1</B></P>

<P STYLE="color: red; font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">&nbsp;</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center"><B>Mersana Therapeutics Provides Business Update
and Announces<BR>
Third Quarter 2022 Financial Results </B></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center">&nbsp;</P>

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<TD STYLE="width: 0.25in"></TD><TD STYLE="width: 0.25in"><FONT STYLE="color: windowtext">-</FONT></TD><TD STYLE="text-align: justify"><I>Completed enrollment in UPLIFT clinical trial; topline data expected mid-2023; potential Biologics
License Application (BLA) submission anticipated by the end of 2023</I></TD></TR></TABLE>

<P STYLE="margin-top: 0pt; margin-bottom: 0pt; font: 10pt Times New Roman, Times, Serif">&nbsp;</P>

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<TD STYLE="width: 0.25in"></TD><TD STYLE="width: 0.25in"><FONT STYLE="color: windowtext">-</FONT></TD><TD STYLE="text-align: justify"><I>Initiated patient enrollment and dosing in Phase 1 clinical trial of XMT-1660 </I></TD></TR></TABLE>

<P STYLE="margin-top: 0pt; margin-bottom: 0pt; font: 10pt Times New Roman, Times, Serif">&nbsp;</P>

<TABLE CELLPADDING="0" CELLSPACING="0" WIDTH="100%" STYLE="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt"><TR STYLE="vertical-align: top">
<TD STYLE="width: 0.25in"></TD><TD STYLE="width: 0.25in"><FONT STYLE="color: windowtext">-</FONT></TD><TD STYLE="text-align: justify"><I>Strengthened balance sheet with <FONT STYLE="color: windowtext">$100 million upfront fee from GSK for
option to co-develop and commercialize XMT-2056</FONT></I></TD></TR></TABLE>

<P STYLE="margin-top: 0pt; margin-bottom: 0pt; font: 10pt Times New Roman, Times, Serif">&nbsp;</P>

<TABLE CELLPADDING="0" CELLSPACING="0" WIDTH="100%" STYLE="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt"><TR STYLE="vertical-align: top">
<TD STYLE="width: 0.25in"></TD><TD STYLE="width: 0.25in">-</TD><TD STYLE="text-align: justify"><I>Conference call today at 8:00 a.m. ET</I></TD></TR></TABLE>

<P STYLE="margin-top: 0pt; margin-bottom: 0pt; font: 10pt Times New Roman, Times, Serif">&nbsp;</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"><B>CAMBRIDGE, Mass., November 7, 2022</B> &#8211; Mersana Therapeutics,
Inc. (NASDAQ: MRSN), a clinical-stage biopharmaceutical company focused on discovering and developing a pipeline of antibody-drug conjugates
(ADCs) targeting cancers in areas of high unmet medical need, today provided a business update and reported financial results for the
third quarter ended September 30, 2022.</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">&nbsp;</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">&#8220;The year 2022 has already been an incredibly productive period
for Mersana as we have advanced UpRi, expanded our clinical pipeline and strengthened our balance sheet with two notable partnerships,&#8221;
said Anna Protopapas, President and Chief Executive Officer of Mersana Therapeutics. &#8220;With significant support from global investigators,
we were able to enroll approximately 270 patients in UPLIFT within just one year, positioning us for a planned top-line data readout and
potential BLA submission next year. We also initiated UP-NEXT, our randomized Phase 3 clinical trial that has the potential to be our
post-approval confirmatory trial in the United States, support approvals in other countries and bring UpRi into an earlier disease setting.
Additionally, we view our recent collaborations as a reflection of the progress we have made in advancing our three innovative platforms
and our position as a partner of choice within the ADC field. We believe these accomplishments strengthen our foundation and will enable
us to enter 2023 with momentum.&#8221;</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">&nbsp;</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"><B><U>Strategic Goals, Recent Developments and Anticipated Milestones</U></B></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">&nbsp;</P>

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<TD STYLE="width: 0.25in"></TD><TD STYLE="width: 0.25in"><FONT STYLE="font-family: Symbol">&middot;</FONT></TD><TD><FONT STYLE="font-family: Times New Roman, Times, Serif"><B>Build Upifitamab Rilsodotin (UpRi), a First-in-Class NaPi2b-Targeting
ADC, into a Foundational Medicine in Ovarian Cancer</B></FONT></TD></TR></TABLE>

<P STYLE="margin-top: 0pt; margin-bottom: 0pt; font: 10pt Times New Roman, Times, Serif">&nbsp;</P>

<TABLE CELLPADDING="0" CELLSPACING="0" WIDTH="100%" STYLE="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt"><TR STYLE="vertical-align: top">
<TD STYLE="width: 0.75in"></TD><TD STYLE="width: 0.25in">-</TD><TD><B>Completed Enrollment in UPLIFT Registrational Trial: </B>UpRi is a first-in-class NaPi2b-targeting ADC with a novel
                                                               scaffold-linker-payload&nbsp;that enables high drug-to-antibody ratio and controlled bystander effect.&#8203; The trial&#8217;s
                                                               primary endpoint is the objective response rate (ORR) in the NaPi2b positive population, and secondary endpoints include the ORR in
                                                               the overall population, as well as duration of objective response and incidence and severity of adverse events. While analysis of
                                                               patient biopsies is ongoing, the company has already exceeded its minimum targeted number of NaPi2b-positive patients necessary for
                                                               the primary endpoint analysis. The company plans to report topline data from the trial in mid-2023 and, assuming positive data,
                                                               submit a potential BLA for UpRi for the treatment of patients with platinum-resistant ovarian cancer to the U.S. Food and Drug
Administration (FDA) by the end of 2023.</TD></TR></TABLE>

<P STYLE="margin-top: 0pt; margin-bottom: 0pt; font: 10pt Times New Roman, Times, Serif">&nbsp;</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt"></P>

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<P STYLE="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt">&nbsp;</P>

<TABLE CELLPADDING="0" CELLSPACING="0" WIDTH="100%" STYLE="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt"><TR STYLE="vertical-align: top">
<TD STYLE="width: 0.75in"></TD><TD STYLE="width: 0.25in">-</TD><TD><B>Initiated Patient Enrollment and Dosing in UP-NEXT Trial: </B>Patient dosing is now underway in UP-NEXT, the company&#8217;s Phase
3 clinical trial of UpRi as monotherapy maintenance following treatment with platinum doublets in recurrent platinum-sensitive ovarian
cancer. If successful, UP-NEXT could serve as a post-approval confirmatory trial in the United States, support potential approvals outside
of the United States and support UpRi&#8217;s expansion into earlier lines of therapy.</TD></TR></TABLE>

<P STYLE="margin-top: 0pt; margin-bottom: 0pt; font: 10pt Times New Roman, Times, Serif">&nbsp;</P>

<TABLE CELLPADDING="0" CELLSPACING="0" WIDTH="100%" STYLE="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt"><TR STYLE="vertical-align: top">
<TD STYLE="width: 0.75in"></TD><TD STYLE="width: 0.25in">-</TD><TD><FONT STYLE="color: windowtext"><B>Nearing Completion of Dose Escalati</B></FONT><B>on in UPGRADE-A Trial: </B>The dose escalation
portion of UPGRADE-A, the company&#8217;s Phase 1/2 trial of UpRi in combination with carboplatin, is now nearly complete. The company
expects to enter the dose expansion portion of UPGRADE-A in the first quarter of 2023 and plans to present data from the trial in the
second half of 2023.</TD></TR></TABLE>

<P STYLE="margin-top: 0pt; margin-bottom: 0pt; font: 10pt Times New Roman, Times, Serif">&nbsp;</P>

<TABLE CELLPADDING="0" CELLSPACING="0" WIDTH="100%" STYLE="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt"><TR STYLE="vertical-align: top">
<TD STYLE="width: 0.25in"></TD><TD STYLE="width: 0.25in"><FONT STYLE="font-family: Symbol">&middot;</FONT></TD><TD><FONT STYLE="font-family: Times New Roman, Times, Serif"><B>Build a Pipeline of Highly Impactful Cancer Medicines</B></FONT></TD></TR></TABLE>

<P STYLE="margin-top: 0pt; margin-bottom: 0pt; font: 10pt Times New Roman, Times, Serif">&nbsp;</P>

<TABLE CELLPADDING="0" CELLSPACING="0" WIDTH="100%" STYLE="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt"><TR STYLE="vertical-align: top">
<TD STYLE="width: 0.75in"></TD><TD STYLE="width: 0.25in">-</TD><TD><FONT STYLE="color: windowtext"><B>Initiated Phase 1 Patient Dosing and Received Fast Track Designation</B></FONT><B> for <FONT STYLE="color: windowtext">XMT-1660:
</FONT></B><FONT STYLE="color: windowtext">XMT-1660 is a B7-H4-directed Dolasynthen ADC with a precise, target-optimized drug-to-antibody
ratio (DAR 6) and Mersana&#8217;s clinically validated DolaLock microtubule inhibitor payload with controlled bystander effect. </FONT>The
company has initiated patient dosing in its multicenter Phase 1 trial investigating XMT-1660 in patients with breast, endometrial and
ovarian cancers. The FDA has granted Fast Track designation to XMT-1660 for the treatment of adult patients with advanced or metastatic
triple-negative breast cancer.</TD></TR></TABLE>

<P STYLE="margin-top: 0pt; margin-bottom: 0pt; font: 10pt Times New Roman, Times, Serif">&nbsp;</P>

<TABLE CELLPADDING="0" CELLSPACING="0" WIDTH="100%" STYLE="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt"><TR STYLE="vertical-align: top">
<TD STYLE="width: 0.75in"></TD><TD STYLE="width: 0.25in">-</TD><TD><B>Readying for Initiation of XMT-2056 Phase 1 Trial: </B>XMT-2056 is a systemically administered Immunosynthen STING agonist ADC
(DAR 8) that is designed to target a novel HER2 epitope and locally activate STING signaling in both tumor-resident immune cells and in
tumor cells, providing the potential to treat patients with HER2-high or -low tumors as monotherapy or in combination with standard-of-care
agents. The company expects to initiate a multicenter Phase 1 open-label trial of XMT-2056 in previously treated patients with advanced/recurrent
solid tumors expressing HER2, including breast, gastric, colorectal and non-small-cell lung cancers later in the fourth quarter of 2022.</TD></TR></TABLE>

<P STYLE="margin-top: 0pt; margin-bottom: 0pt; font: 10pt Times New Roman, Times, Serif">&nbsp;</P>

<TABLE CELLPADDING="0" CELLSPACING="0" STYLE="width: 100%; font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt"><TR STYLE="vertical-align: top; text-align: justify">
<TD STYLE="width: 0.25in"></TD><TD STYLE="width: 0.25in; text-align: left"><FONT STYLE="font-family: Symbol">&middot;</FONT></TD><TD STYLE="text-align: justify"><FONT STYLE="font-family: Times New Roman, Times, Serif"><B>Build
Mersana with Strategic Partners</B></FONT></TD>
</TR></TABLE>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0 0pt 0.5in; text-indent: -0.25in">&nbsp;</P>

<TABLE CELLPADDING="0" CELLSPACING="0" WIDTH="100%" STYLE="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt"><TR STYLE="vertical-align: top">
<TD STYLE="width: 0.75in"></TD><TD STYLE="width: 0.25in">-</TD><TD><B>Received $100 Million Upfront Option Purchase Fee from GSK: </B>In August 2022, Mersana announced a global collaboration providing
GSK plc an exclusive option to co-develop and commercialize XMT-2056. Under the terms of the agreement, Mersana received an upfront option
purchase fee of $100 million. Mersana is also eligible to receive up to $1.36 billion in the form of an option exercise payment and development,
regulatory and commercial milestone payments if GSK exercises its option. Mersana has retained options to profit-share and to co-promote
in the United States. If it exercises its profit-share option, Mersana will be eligible to receive tiered royalties on net sales outside
of the United States. If Mersana does not elect to profit-share, it is eligible to receive double-digit tiered royalties on global net
sales.</TD></TR></TABLE>

<P STYLE="margin-top: 0pt; margin-bottom: 0pt; font: 10pt Times New Roman, Times, Serif">&nbsp;</P>




<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"></P>

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<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">&nbsp;</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"><B><U>Third Quarter 2022 Financial Results</U></B></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">&nbsp;</P>

<TABLE CELLPADDING="0" CELLSPACING="0" WIDTH="100%" STYLE="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt"><TR STYLE="vertical-align: top">
<TD STYLE="width: 0.25in"></TD><TD STYLE="width: 0.25in"><FONT STYLE="font-family: Symbol">&middot;</FONT></TD><TD><FONT STYLE="font-family: Times New Roman, Times, Serif">Net cash provided by operating activities in the third quarter of 2022, including
the impact of the aforementioned $100 million upfront payment from GSK, was $54.6 million.</FONT></TD></TR></TABLE>

<P STYLE="margin-top: 0pt; margin-bottom: 0pt; font: 10pt Times New Roman, Times, Serif">&nbsp;</P>

<TABLE CELLPADDING="0" CELLSPACING="0" WIDTH="100%" STYLE="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt"><TR STYLE="vertical-align: top">
<TD STYLE="width: 0.25in"></TD><TD STYLE="width: 0.25in"><FONT STYLE="font-family: Symbol">&middot;</FONT></TD><TD><FONT STYLE="font-family: Times New Roman, Times, Serif">Cash, cash equivalents and marketable securities as of September 30, 2022,
were $290.1 million, compared to cash and cash equivalents of $177.9 million as of December 31, 2021. Mersana expects that its available
funds will be sufficient to support its operating plan commitments into the first half of 2024.</FONT></TD></TR></TABLE>

<P STYLE="margin-top: 0pt; margin-bottom: 0pt; font: 10pt Times New Roman, Times, Serif">&nbsp;</P>

<TABLE CELLPADDING="0" CELLSPACING="0" WIDTH="100%" STYLE="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt"><TR STYLE="vertical-align: top">
<TD STYLE="width: 0.25in"></TD><TD STYLE="width: 0.25in"><FONT STYLE="font-family: Symbol">&middot;</FONT></TD><TD><FONT STYLE="font-family: Times New Roman, Times, Serif">Collaboration revenue for the third quarter of 2022 was $5.6 million, compared
to an immaterial amount for the same period in 2021. The year-over-year increase was primarily related to the company&#8217;s recent collaboration
agreements with Janssen and GSK.</FONT></TD></TR></TABLE>

<P STYLE="margin-top: 0pt; margin-bottom: 0pt; font: 10pt Times New Roman, Times, Serif">&nbsp;</P>

<TABLE CELLPADDING="0" CELLSPACING="0" WIDTH="100%" STYLE="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt"><TR STYLE="vertical-align: top">
<TD STYLE="width: 0.25in"></TD><TD STYLE="width: 0.25in"><FONT STYLE="font-family: Symbol">&middot;</FONT></TD><TD><FONT STYLE="font-family: Times New Roman, Times, Serif">Research and development (R&amp;D) expenses for the third quarter of 2022
were $50.6 million, compared to $35.3 million for the same period in 2021. Included in third quarter 2022 R&amp;D expenses were $2.9 million
in non-cash stock-based compensation expenses. The year-over-year increase in R&amp;D expenses was primarily related to higher manufacturing
and clinical costs related to UpRi and to an increase in headcount. </FONT></TD></TR></TABLE>

<P STYLE="margin-top: 0pt; margin-bottom: 0pt; font: 10pt Times New Roman, Times, Serif">&nbsp;</P>

<TABLE CELLPADDING="0" CELLSPACING="0" WIDTH="100%" STYLE="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt"><TR STYLE="vertical-align: top">
<TD STYLE="width: 0.25in"></TD><TD STYLE="width: 0.25in"><FONT STYLE="font-family: Symbol; color: windowtext">&middot;</FONT></TD><TD><FONT STYLE="font-family: Times New Roman, Times, Serif">General and administrative (G&amp;A) expenses for the third quarter of 2022
were $14.6 million, compared to $10.1 million during the same period in 2021<FONT STYLE="color: windowtext">. Included in third quarter
2022 G&amp;A expenses were $2.5 million in non-cash stock-based compensation expenses. The year-over-year increase in G&amp;A expenses
was primarily related to increases in consulting and professional fees, and in headcount.</FONT></FONT></TD></TR></TABLE>

<P STYLE="margin-top: 0pt; margin-bottom: 0pt; font: 10pt Times New Roman, Times, Serif">&nbsp;</P>

<TABLE CELLPADDING="0" CELLSPACING="0" WIDTH="100%" STYLE="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt"><TR STYLE="vertical-align: top">
<TD STYLE="width: 0.25in"></TD><TD STYLE="width: 0.25in"><FONT STYLE="font-family: Symbol">&middot;</FONT></TD><TD><FONT STYLE="font-family: Times New Roman, Times, Serif">Net loss for the third quarter of 2022 was $59.8 million, or $0.61 per share,
compared to a net loss of $45.5 million, or $0.63 per share, for the same period in 2021. </FONT></TD></TR></TABLE>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"><B>&nbsp;</B></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"><B><U>Conference Call Reminder</U></B></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">&nbsp;</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">Mersana will host a conference call today at 8:00 a.m. ET to discuss
business updates and its financial results for the third quarter of 2022. To access the call, please dial 646-307-1963 (domestic) or 800-715-9871
(international) and provide the Conference ID 9941053. A live webcast of the presentation will be available on the Investors &amp; Media
section of the Mersana website at www.mersana.com, and a replay of the webcast will be available in the same location following the conference
call for approximately 90 days.</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"><B>&nbsp;</B></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"><B><U>About Mersana Therapeutics</U></B></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">&nbsp;</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"><FONT STYLE="background-color: white">Mersana Therapeutics is a clinical-stage
biopharmaceutical company using its differentiated and proprietary ADC platforms to rapidly develop novel ADCs with optimal efficacy,
safety and tolerability to meaningfully improve the lives of people fighting cancer. Mersana&#8217;s lead product candidate, upifitamab
rilsodotin (UpRi), is a Dolaflexin ADC targeting NaPi2b that is being studied in UPLIFT, a single-arm registrational trial in patients
with platinum-resistant ovarian cancer; UPGRADE, a Phase 1/2 umbrella trial evaluating UpRi in combination with other ovarian cancer
therapies; and UP-NEXT, a Phase 3 clinical trial of UpRi as monotherapy maintenance following treatment with platinum doublets in recurrent
platinum-sensitive ovarian cancer. Mersana is also advancing XMT-1660, a Dolasynthen ADC targeting B7-H4, and XMT-2056, an Immunosynthen
ADC targeting a novel epitope of human epidermal growth factor receptor 2 (HER2), in addition to </FONT>other earlier-stage assets. In
addition, multiple partners are using Mersana&#8217;s platforms to advance their ADC pipelines. Mersana Therapeutics was named among
the 2021 Top Places to Work in Massachusetts by The Boston Globe. Mersana routinely posts information that may be useful to investors
on the &#8220;Investors &amp; Media&#8221; section of its website at <FONT STYLE="font-family: Times New Roman, Times, Serif; font-size: 10pt; background-color: white"><U>www.mersana.com</U>.</FONT></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">&nbsp;</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"></P>

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<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">&nbsp;</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"><B><U>Forward-Looking Statements</U></B></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"><B>&nbsp;</B></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"><FONT STYLE="background-color: white">This press release contains &#8220;forward-looking&#8221;
statements and information within the meaning of the Private Securities Litigation Reform Act of 1995. These statements may be identified
by words such as &#8220;aims,&#8221; &#8220;anticipates,&#8221; &#8220;believes,&#8221; &#8220;could,&#8221; &#8220;estimates,&#8221;
&#8220;expects,&#8221; &#8220;forecasts,&#8221; &#8220;goal,&#8221; &#8220;intends,&#8221; &#8220;may,&#8221; &#8220;plans,&#8221; &#8220;possible,&#8221;
&#8220;potential,&#8221; &#8220;seeks,&#8221; &#8220;will&#8221; and variations of these words or similar expressions, although not all
forward-looking statements contain these words. Forward-looking statements in this press release include, but are not limited to, statements
concerning the therapeutic potential of Mersana&#8217;s product candidates; the potential of Mersana&#8217;s platforms and technology;
the design, progression, timing and objectives of Mersana&#8217;s clinical trials and the release of data from those trials, including
UPLIFT; Mersana&#8217;s potential BLA submission for UpRi; Mersana&#8217;s anticipated initiation of its Phase 1 clinical trial of XMT-2056
and the dose expansion portion of its UPGRADE trial; the ability of trial results to support marketing approvals or other objectives;
the development and potential of Mersana&#8217;s pipeline of ADC candidates; Mersana&#8217;s expected cash runway; GSK&#8217;s potential
exercise of its option for a license to co-develop and commercialize XMT-2056; Mersana&#8217;s options to share in U.S. profits and losses
and/or to co-promote licensed products pursuant to its agreement with GSK; and potential option exercise, milestone and royalty revenues
under Mersana&#8217;s collaboration and license agreements. Mersana may not actually achieve the plans, intentions or expectations disclosed
in these forward-looking statements, and you should not place undue reliance on these forward-looking statements. Actual results or events
could differ materially from the plans, intentions and expectations disclosed in these forward-looking statements as a result of various
factors, including, among other things, uncertainties inherent in research and development, in the initiation of clinical trials and in
the clinical development of Mersana&#8217;s product candidates; the risk that Mersana&#8217;s anticipated clinical trials may not be initiated
on schedule, if at all; the risk that Mersana may not realize the intended benefits of its platforms, technology and collaborations, including
that GSK may not exercise its option for a license; whether the outcomes of preclinical studies will be predictive of clinical trial results;
whether initial or interim results from a clinical trial will be predictive of the final results of the trial or the results of future
trials; risks to clinical trial site initiation, patient enrollment and follow-up, as well as to Mersana&#8217;s and its collaborators&#8217;
abilities to meet other anticipated deadlines and milestones, whether presented by the ongoing COVID-19 pandemic or otherwise; the risk
that Mersana&#8217;s projections regarding its expected cash runway are inaccurate or that its conduct of its business requires more cash
than anticipated; the risk that any of Mersana&#8217;s collaborators fail to make any payments owed to Mersana; and other important factors,
any of which could cause Mersana&#8217;s actual results to differ from those contained in the forward-looking statements, that are described
in greater detail in the section entitled &#8220;Risk Factors&#8221; in Mersana&#8217;s Quarterly Report on Form 10-Q filed with the Securities
and Exchange Commission (&#8220;SEC&#8221;) on August 8, 2022, as well as in other filings Mersana may make with the SEC in the future.
Any forward-looking statements contained in this press release speak only as of the date hereof, and Mersana expressly disclaims any obligation
to update any forward-looking statements contained herein, whether because of any new information, future events, changed circumstances
or otherwise, except as otherwise required by law.</FONT></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"><FONT STYLE="background-color: white">&nbsp;</FONT></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"><FONT STYLE="background-color: white"></FONT></P>

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<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"><FONT STYLE="background-color: white">&nbsp;</FONT></P>




<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center"><FONT STYLE="background-color: white"><B>Mersana
Therapeutics, Inc.</B></FONT></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center"><FONT STYLE="background-color: white"><B>Selected
Condensed Consolidated Balance Sheet Data</B></FONT></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center"><FONT STYLE="background-color: white"><B>(in thousands
and unaudited)</B></FONT></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center"><FONT STYLE="background-color: white"><B>&nbsp;</B></FONT></P>

<TABLE CELLPADDING="0" CELLSPACING="0" STYLE="border-collapse: collapse; width: 100%; font: 10pt Times New Roman, Times, Serif">
  <TR STYLE="vertical-align: bottom">
    <TD STYLE="font-size: 10pt; font-weight: bold; text-align: center">&nbsp;</TD><TD STYLE="font-size: 10pt; font-weight: bold; padding-bottom: 1pt">&nbsp;</TD>
    <TD COLSPAN="2" STYLE="font-size: 10pt; font-weight: bold; text-align: center; border-bottom: Black 1pt solid">September 30,<BR> 2022</TD><TD STYLE="padding-bottom: 1pt; font-size: 10pt; font-weight: bold">&nbsp;</TD><TD STYLE="font-size: 10pt; font-weight: bold; padding-bottom: 1pt">&nbsp;</TD>
    <TD COLSPAN="2" STYLE="font-size: 10pt; font-weight: bold; text-align: center; border-bottom: Black 1pt solid">December 31,<BR> 2021</TD><TD STYLE="padding-bottom: 1pt; font-size: 10pt; font-weight: bold">&nbsp;</TD></TR>
  <TR STYLE="vertical-align: bottom; background-color: rgb(204,238,255)">
    <TD STYLE="width: 74%; font-size: 10pt; text-align: left">Cash, cash equivalents and marketable securities</TD><TD STYLE="width: 1%; font-size: 10pt">&nbsp;</TD>
    <TD STYLE="width: 1%; font-size: 10pt; text-align: left">$</TD><TD STYLE="width: 10%; font-size: 10pt; text-align: right">290,126</TD><TD STYLE="width: 1%; font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="width: 1%; font-size: 10pt">&nbsp;</TD>
    <TD STYLE="width: 1%; font-size: 10pt; text-align: left">$</TD><TD STYLE="width: 10%; font-size: 10pt; text-align: right">177,947</TD><TD STYLE="width: 1%; font-size: 10pt; text-align: left">&nbsp;</TD></TR>
  <TR STYLE="vertical-align: bottom; background-color: White">
    <TD STYLE="font-size: 10pt">Working capital<SUP>(1)</SUP></TD><TD STYLE="font-size: 10pt">&nbsp;</TD>
    <TD STYLE="font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="font-size: 10pt; text-align: right">211,243</TD><TD STYLE="font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="font-size: 10pt">&nbsp;</TD>
    <TD STYLE="font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="font-size: 10pt; text-align: right">141,375</TD><TD STYLE="font-size: 10pt; text-align: left">&nbsp;</TD></TR>
  <TR STYLE="vertical-align: bottom; background-color: rgb(204,238,255)">
    <TD STYLE="font-size: 10pt; text-align: left">Total assets</TD><TD STYLE="font-size: 10pt">&nbsp;</TD>
    <TD STYLE="font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="font-size: 10pt; text-align: right">314,850</TD><TD STYLE="font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="font-size: 10pt">&nbsp;</TD>
    <TD STYLE="font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="font-size: 10pt; text-align: right">206,111</TD><TD STYLE="font-size: 10pt; text-align: left">&nbsp;</TD></TR>
  <TR STYLE="vertical-align: bottom; background-color: White">
    <TD STYLE="font-size: 10pt; text-align: left">Total stockholders' equity</TD><TD STYLE="font-size: 10pt">&nbsp;</TD>
    <TD STYLE="font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="font-size: 10pt; text-align: right">90,229</TD><TD STYLE="font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="font-size: 10pt">&nbsp;</TD>
    <TD STYLE="font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="font-size: 10pt; text-align: right">121,741</TD><TD STYLE="font-size: 10pt; text-align: left">&nbsp;</TD></TR>
  </TABLE>



<P STYLE="margin: 0">&nbsp;</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt"><FONT STYLE="font-size: 10pt"><SUP>(1) </SUP>The
Company defines working capital as current assets less current liabilities.</FONT></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt"><B>&nbsp;</B></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center"><B>Mersana Therapeutics, Inc.</B></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center"><B>Condensed Consolidated Statement of Operations</B></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center"><B>(in thousands, except share and per share data,
and unaudited)</B></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center"><B>&nbsp;</B></P>

<TABLE CELLPADDING="0" CELLSPACING="0" STYLE="border-collapse: collapse; width: 100%; font: 10pt Times New Roman, Times, Serif">
  <TR STYLE="vertical-align: bottom">
    <TD STYLE="font-size: 10pt; font-weight: bold">&nbsp;</TD><TD STYLE="font-size: 10pt; font-weight: bold; padding-bottom: 1pt">&nbsp;</TD>
    <TD COLSPAN="6" STYLE="font-size: 10pt; font-weight: bold; text-align: center; border-bottom: Black 1pt solid">Three months ended</TD><TD STYLE="padding-bottom: 1pt; font-size: 10pt; font-weight: bold">&nbsp;</TD><TD STYLE="font-size: 10pt; font-weight: bold; padding-bottom: 1pt">&nbsp;</TD>
    <TD COLSPAN="6" STYLE="font-size: 10pt; font-weight: bold; text-align: center; border-bottom: Black 1pt solid">Nine months ended</TD><TD STYLE="padding-bottom: 1pt; font-size: 10pt; font-weight: bold">&nbsp;</TD></TR>
  <TR STYLE="vertical-align: bottom">
    <TD STYLE="font-size: 10pt; font-weight: bold; text-align: center">&nbsp;</TD><TD STYLE="font-size: 10pt; font-weight: bold; padding-bottom: 1pt">&nbsp;</TD>
    <TD COLSPAN="2" STYLE="font-size: 10pt; font-weight: bold; text-align: center; border-bottom: Black 1pt solid">September 30,<BR> 2022</TD><TD STYLE="padding-bottom: 1pt; font-size: 10pt; font-weight: bold">&nbsp;</TD><TD STYLE="font-size: 10pt; font-weight: bold; padding-bottom: 1pt">&nbsp;</TD>
    <TD COLSPAN="2" STYLE="font-size: 10pt; font-weight: bold; text-align: center; border-bottom: Black 1pt solid">September 30,<BR> 2021</TD><TD STYLE="padding-bottom: 1pt; font-size: 10pt; font-weight: bold">&nbsp;</TD><TD STYLE="font-size: 10pt; font-weight: bold; padding-bottom: 1pt">&nbsp;</TD>
    <TD COLSPAN="2" STYLE="font-size: 10pt; font-weight: bold; text-align: center; border-bottom: Black 1pt solid">September 30,<BR> 2022</TD><TD STYLE="padding-bottom: 1pt; font-size: 10pt; font-weight: bold">&nbsp;</TD><TD STYLE="font-size: 10pt; font-weight: bold; padding-bottom: 1pt">&nbsp;</TD>
    <TD COLSPAN="2" STYLE="font-size: 10pt; font-weight: bold; text-align: center; border-bottom: Black 1pt solid">September 30,<BR> 2021</TD><TD STYLE="padding-bottom: 1pt; font-size: 10pt; font-weight: bold">&nbsp;</TD></TR>
  <TR STYLE="vertical-align: bottom; background-color: rgb(204,238,255)">
    <TD STYLE="width: 48%; font-size: 10pt; text-align: left">Collaboration revenue</TD><TD STYLE="width: 1%; font-size: 10pt">&nbsp;</TD>
    <TD STYLE="width: 1%; font-size: 10pt; text-align: left">$</TD><TD STYLE="width: 10%; font-size: 10pt; text-align: right">5,573</TD><TD STYLE="width: 1%; font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="width: 1%; font-size: 10pt">&nbsp;</TD>
    <TD STYLE="width: 1%; font-size: 10pt; text-align: left">$</TD><TD STYLE="width: 10%; font-size: 10pt; text-align: right">11</TD><TD STYLE="width: 1%; font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="width: 1%; font-size: 10pt">&nbsp;</TD>
    <TD STYLE="width: 1%; font-size: 10pt; text-align: left">$</TD><TD STYLE="width: 10%; font-size: 10pt; text-align: right">11,893</TD><TD STYLE="width: 1%; font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="width: 1%; font-size: 10pt">&nbsp;</TD>
    <TD STYLE="width: 1%; font-size: 10pt; text-align: left">$</TD><TD STYLE="width: 10%; font-size: 10pt; text-align: right">32</TD><TD STYLE="width: 1%; font-size: 10pt; text-align: left">&nbsp;</TD></TR>
  <TR STYLE="vertical-align: bottom; background-color: White">
    <TD STYLE="font-size: 10pt; text-align: left">Operating expenses:</TD><TD STYLE="font-size: 10pt">&nbsp;</TD>
    <TD STYLE="font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="font-size: 10pt; text-align: right">&nbsp;</TD><TD STYLE="font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="font-size: 10pt">&nbsp;</TD>
    <TD STYLE="font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="font-size: 10pt; text-align: right">&nbsp;</TD><TD STYLE="font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="font-size: 10pt">&nbsp;</TD>
    <TD STYLE="font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="font-size: 10pt; text-align: right">&nbsp;</TD><TD STYLE="font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="font-size: 10pt">&nbsp;</TD>
    <TD STYLE="font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="font-size: 10pt; text-align: right">&nbsp;</TD><TD STYLE="font-size: 10pt; text-align: left">&nbsp;</TD></TR>
  <TR STYLE="vertical-align: bottom; background-color: rgb(204,238,255)">
    <TD STYLE="padding-left: 0.125in; font-size: 10pt; text-align: left">Research and development</TD><TD STYLE="font-size: 10pt">&nbsp;</TD>
    <TD STYLE="font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="font-size: 10pt; text-align: right">50,639</TD><TD STYLE="font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="font-size: 10pt">&nbsp;</TD>
    <TD STYLE="font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="font-size: 10pt; text-align: right">35,275</TD><TD STYLE="font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="font-size: 10pt">&nbsp;</TD>
    <TD STYLE="font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="font-size: 10pt; text-align: right">127,676</TD><TD STYLE="font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="font-size: 10pt">&nbsp;</TD>
    <TD STYLE="font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="font-size: 10pt; text-align: right">94,645</TD><TD STYLE="font-size: 10pt; text-align: left">&nbsp;</TD></TR>
  <TR STYLE="vertical-align: bottom; background-color: White">
    <TD STYLE="padding-left: 0.125in; font-size: 10pt; text-align: left; padding-bottom: 1pt">General and administrative</TD><TD STYLE="font-size: 10pt; padding-bottom: 1pt">&nbsp;</TD>
    <TD STYLE="border-bottom: Black 1pt solid; font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="border-bottom: Black 1pt solid; font-size: 10pt; text-align: right">14,573</TD><TD STYLE="padding-bottom: 1pt; font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="font-size: 10pt; padding-bottom: 1pt">&nbsp;</TD>
    <TD STYLE="border-bottom: Black 1pt solid; font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="border-bottom: Black 1pt solid; font-size: 10pt; text-align: right">10,124</TD><TD STYLE="padding-bottom: 1pt; font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="font-size: 10pt; padding-bottom: 1pt">&nbsp;</TD>
    <TD STYLE="border-bottom: Black 1pt solid; font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="border-bottom: Black 1pt solid; font-size: 10pt; text-align: right">42,158</TD><TD STYLE="padding-bottom: 1pt; font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="font-size: 10pt; padding-bottom: 1pt">&nbsp;</TD>
    <TD STYLE="border-bottom: Black 1pt solid; font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="border-bottom: Black 1pt solid; font-size: 10pt; text-align: right">26,214</TD><TD STYLE="padding-bottom: 1pt; font-size: 10pt; text-align: left">&nbsp;</TD></TR>
  <TR STYLE="vertical-align: bottom; background-color: rgb(204,238,255)">
    <TD STYLE="font-size: 10pt; text-align: left">Total operating expenses</TD><TD STYLE="font-size: 10pt">&nbsp;</TD>
    <TD STYLE="font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="font-size: 10pt; text-align: right">65,212</TD><TD STYLE="font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="font-size: 10pt">&nbsp;</TD>
    <TD STYLE="font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="font-size: 10pt; text-align: right">45,399</TD><TD STYLE="font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="font-size: 10pt">&nbsp;</TD>
    <TD STYLE="font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="font-size: 10pt; text-align: right">169,834</TD><TD STYLE="font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="font-size: 10pt">&nbsp;</TD>
    <TD STYLE="font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="font-size: 10pt; text-align: right">120,859</TD><TD STYLE="font-size: 10pt; text-align: left">&nbsp;</TD></TR>
  <TR STYLE="vertical-align: bottom; background-color: White">
    <TD STYLE="font-size: 10pt; text-align: left; padding-bottom: 1pt">Total other income (expense), net</TD><TD STYLE="font-size: 10pt; padding-bottom: 1pt">&nbsp;</TD>
    <TD STYLE="border-bottom: Black 1pt solid; font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="border-bottom: Black 1pt solid; font-size: 10pt; text-align: right">(172</TD><TD STYLE="padding-bottom: 1pt; font-size: 10pt; text-align: left">)</TD><TD STYLE="font-size: 10pt; padding-bottom: 1pt">&nbsp;</TD>
    <TD STYLE="border-bottom: Black 1pt solid; font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="border-bottom: Black 1pt solid; font-size: 10pt; text-align: right">(83</TD><TD STYLE="padding-bottom: 1pt; font-size: 10pt; text-align: left">)</TD><TD STYLE="font-size: 10pt; padding-bottom: 1pt">&nbsp;</TD>
    <TD STYLE="border-bottom: Black 1pt solid; font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="border-bottom: Black 1pt solid; font-size: 10pt; text-align: right">(1,347</TD><TD STYLE="padding-bottom: 1pt; font-size: 10pt; text-align: left">)</TD><TD STYLE="font-size: 10pt; padding-bottom: 1pt">&nbsp;</TD>
    <TD STYLE="border-bottom: Black 1pt solid; font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="border-bottom: Black 1pt solid; font-size: 10pt; text-align: right">(250</TD><TD STYLE="padding-bottom: 1pt; font-size: 10pt; text-align: left">)</TD></TR>
  <TR STYLE="vertical-align: bottom; background-color: rgb(204,238,255)">
    <TD STYLE="font-size: 10pt; text-align: left; padding-bottom: 2.5pt">Net loss</TD><TD STYLE="font-size: 10pt; padding-bottom: 2.5pt">&nbsp;</TD>
    <TD STYLE="border-bottom: Black 2.5pt double; font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="border-bottom: Black 2.5pt double; font-size: 10pt; text-align: right">(59,811</TD><TD STYLE="padding-bottom: 2.5pt; font-size: 10pt; text-align: left">)</TD><TD STYLE="font-size: 10pt; padding-bottom: 2.5pt">&nbsp;</TD>
    <TD STYLE="border-bottom: Black 2.5pt double; font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="border-bottom: Black 2.5pt double; font-size: 10pt; text-align: right">(45,471</TD><TD STYLE="padding-bottom: 2.5pt; font-size: 10pt; text-align: left">)</TD><TD STYLE="font-size: 10pt; padding-bottom: 2.5pt">&nbsp;</TD>
    <TD STYLE="border-bottom: Black 2.5pt double; font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="border-bottom: Black 2.5pt double; font-size: 10pt; text-align: right">(159,288</TD><TD STYLE="padding-bottom: 2.5pt; font-size: 10pt; text-align: left">)</TD><TD STYLE="font-size: 10pt; padding-bottom: 2.5pt">&nbsp;</TD>
    <TD STYLE="border-bottom: Black 2.5pt double; font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="border-bottom: Black 2.5pt double; font-size: 10pt; text-align: right">(121,077</TD><TD STYLE="padding-bottom: 2.5pt; font-size: 10pt; text-align: left">)</TD></TR>
  <TR STYLE="vertical-align: bottom; background-color: White">
    <TD STYLE="font-size: 10pt; text-align: left; padding-bottom: 2.5pt">Net loss per share &mdash; basic and diluted</TD><TD STYLE="font-size: 10pt; padding-bottom: 2.5pt">&nbsp;</TD>
    <TD STYLE="border-bottom: Black 2.5pt double; font-size: 10pt; text-align: left">$</TD><TD STYLE="border-bottom: Black 2.5pt double; font-size: 10pt; text-align: right">(0.61</TD><TD STYLE="padding-bottom: 2.5pt; font-size: 10pt; text-align: left">)</TD><TD STYLE="font-size: 10pt; padding-bottom: 2.5pt">&nbsp;</TD>
    <TD STYLE="border-bottom: Black 2.5pt double; font-size: 10pt; text-align: left">$</TD><TD STYLE="border-bottom: Black 2.5pt double; font-size: 10pt; text-align: right">(0.63</TD><TD STYLE="padding-bottom: 2.5pt; font-size: 10pt; text-align: left">)</TD><TD STYLE="font-size: 10pt; padding-bottom: 2.5pt">&nbsp;</TD>
    <TD STYLE="border-bottom: Black 2.5pt double; font-size: 10pt; text-align: left">$</TD><TD STYLE="border-bottom: Black 2.5pt double; font-size: 10pt; text-align: right">(1.75</TD><TD STYLE="padding-bottom: 2.5pt; font-size: 10pt; text-align: left">)</TD><TD STYLE="font-size: 10pt; padding-bottom: 2.5pt">&nbsp;</TD>
    <TD STYLE="border-bottom: Black 2.5pt double; font-size: 10pt; text-align: left">$</TD><TD STYLE="border-bottom: Black 2.5pt double; font-size: 10pt; text-align: right">(1.73</TD><TD STYLE="padding-bottom: 2.5pt; font-size: 10pt; text-align: left">)</TD></TR>
  <TR STYLE="vertical-align: bottom; background-color: rgb(204,238,255)">
    <TD STYLE="font-size: 10pt; text-align: left; padding-bottom: 2.5pt">Weighted-average number of common shares &mdash; basic and diluted</TD><TD STYLE="font-size: 10pt; padding-bottom: 2.5pt">&nbsp;</TD>
    <TD STYLE="border-bottom: Black 2.5pt double; font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="border-bottom: Black 2.5pt double; font-size: 10pt; text-align: right">97,641,936</TD><TD STYLE="padding-bottom: 2.5pt; font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="font-size: 10pt; padding-bottom: 2.5pt">&nbsp;</TD>
    <TD STYLE="border-bottom: Black 2.5pt double; font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="border-bottom: Black 2.5pt double; font-size: 10pt; text-align: right">71,753,004</TD><TD STYLE="padding-bottom: 2.5pt; font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="font-size: 10pt; padding-bottom: 2.5pt">&nbsp;</TD>
    <TD STYLE="border-bottom: Black 2.5pt double; font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="border-bottom: Black 2.5pt double; font-size: 10pt; text-align: right">91,173,989</TD><TD STYLE="padding-bottom: 2.5pt; font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="font-size: 10pt; padding-bottom: 2.5pt">&nbsp;</TD>
    <TD STYLE="border-bottom: Black 2.5pt double; font-size: 10pt; text-align: left">&nbsp;</TD><TD STYLE="border-bottom: Black 2.5pt double; font-size: 10pt; text-align: right">70,129,236</TD><TD STYLE="padding-bottom: 2.5pt; font-size: 10pt; text-align: left">&nbsp;</TD></TR>
  </TABLE>



<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"><B>&nbsp;</B></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center"><B>###</B></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"><B>&nbsp;</B></P>

<P STYLE="text-indent: 0; font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"><B>Contact:</B></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; text-indent: 0; margin: 0pt 0"><B>&nbsp;</B></P>

<P STYLE="text-indent: 0; font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">Jason Fredette</P>

<P STYLE="text-indent: 0; font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">617-498-0020</P>

<P STYLE="text-indent: 0; font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"><U>jason.fredette@mersana.com</U></P>



<P STYLE="margin: 0">&nbsp;</P>

<P STYLE="margin: 0"></P>

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<XBRL>
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<DESCRIPTION>XBRL TAXONOMY EXTENSION LABEL LINKBASE
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<XBRL>
<?xml version="1.0" encoding="US-ASCII" standalone="no"?>
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      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_EntityFileNumber" xlink:to="dei_EntityFileNumber_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_EntityFileNumber_lbl" xml:lang="en-US">Entity File Number</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2021q4/dei-2021q4.xsd#dei_EntityRegistrantName" xlink:label="dei_EntityRegistrantName" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_EntityRegistrantName" xlink:to="dei_EntityRegistrantName_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_EntityRegistrantName_lbl" xml:lang="en-US">Entity Registrant Name</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2021q4/dei-2021q4.xsd#dei_EntityCentralIndexKey" xlink:label="dei_EntityCentralIndexKey" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_EntityCentralIndexKey" xlink:to="dei_EntityCentralIndexKey_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_EntityCentralIndexKey_lbl" xml:lang="en-US">Entity Central Index Key</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2021q4/dei-2021q4.xsd#dei_EntityPrimarySicNumber" xlink:label="dei_EntityPrimarySicNumber" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_EntityPrimarySicNumber" xlink:to="dei_EntityPrimarySicNumber_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_EntityPrimarySicNumber_lbl" xml:lang="en-US">Entity Primary SIC Number</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2021q4/dei-2021q4.xsd#dei_EntityTaxIdentificationNumber" xlink:label="dei_EntityTaxIdentificationNumber" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_EntityTaxIdentificationNumber" xlink:to="dei_EntityTaxIdentificationNumber_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_EntityTaxIdentificationNumber_lbl" xml:lang="en-US">Entity Tax Identification Number</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2021q4/dei-2021q4.xsd#dei_EntityIncorporationStateCountryCode" xlink:label="dei_EntityIncorporationStateCountryCode" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_EntityIncorporationStateCountryCode" xlink:to="dei_EntityIncorporationStateCountryCode_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_EntityIncorporationStateCountryCode_lbl" xml:lang="en-US">Entity Incorporation, State or Country Code</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2021q4/dei-2021q4.xsd#dei_EntityAddressAddressLine1" xlink:label="dei_EntityAddressAddressLine1" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_EntityAddressAddressLine1" xlink:to="dei_EntityAddressAddressLine1_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_EntityAddressAddressLine1_lbl" xml:lang="en-US">Entity Address, Address Line One</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2021q4/dei-2021q4.xsd#dei_EntityAddressAddressLine2" xlink:label="dei_EntityAddressAddressLine2" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_EntityAddressAddressLine2" xlink:to="dei_EntityAddressAddressLine2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_EntityAddressAddressLine2_lbl" xml:lang="en-US">Entity Address, Address Line Two</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2021q4/dei-2021q4.xsd#dei_EntityAddressAddressLine3" xlink:label="dei_EntityAddressAddressLine3" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_EntityAddressAddressLine3" xlink:to="dei_EntityAddressAddressLine3_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_EntityAddressAddressLine3_lbl" xml:lang="en-US">Entity Address, Address Line Three</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2021q4/dei-2021q4.xsd#dei_EntityAddressCityOrTown" xlink:label="dei_EntityAddressCityOrTown" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_EntityAddressCityOrTown" xlink:to="dei_EntityAddressCityOrTown_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_EntityAddressCityOrTown_lbl" xml:lang="en-US">Entity Address, City or Town</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2021q4/dei-2021q4.xsd#dei_EntityAddressStateOrProvince" xlink:label="dei_EntityAddressStateOrProvince" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_EntityAddressStateOrProvince" xlink:to="dei_EntityAddressStateOrProvince_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_EntityAddressStateOrProvince_lbl" xml:lang="en-US">Entity Address, State or Province</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2021q4/dei-2021q4.xsd#dei_EntityAddressCountry" xlink:label="dei_EntityAddressCountry" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_EntityAddressCountry" xlink:to="dei_EntityAddressCountry_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_EntityAddressCountry_lbl" xml:lang="en-US">Entity Address, Country</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2021q4/dei-2021q4.xsd#dei_EntityAddressPostalZipCode" xlink:label="dei_EntityAddressPostalZipCode" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_EntityAddressPostalZipCode" xlink:to="dei_EntityAddressPostalZipCode_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_EntityAddressPostalZipCode_lbl" xml:lang="en-US">Entity Address, Postal Zip Code</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2021q4/dei-2021q4.xsd#dei_CountryRegion" xlink:label="dei_CountryRegion" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_CountryRegion" xlink:to="dei_CountryRegion_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_CountryRegion_lbl" xml:lang="en-US">Country Region</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2021q4/dei-2021q4.xsd#dei_CityAreaCode" xlink:label="dei_CityAreaCode" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_CityAreaCode" xlink:to="dei_CityAreaCode_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_CityAreaCode_lbl" xml:lang="en-US">City Area Code</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2021q4/dei-2021q4.xsd#dei_LocalPhoneNumber" xlink:label="dei_LocalPhoneNumber" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_LocalPhoneNumber" xlink:to="dei_LocalPhoneNumber_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_LocalPhoneNumber_lbl" xml:lang="en-US">Local Phone Number</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2021q4/dei-2021q4.xsd#dei_Extension" xlink:label="dei_Extension" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_Extension" xlink:to="dei_Extension_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_Extension_lbl" xml:lang="en-US">Extension</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2021q4/dei-2021q4.xsd#dei_WrittenCommunications" xlink:label="dei_WrittenCommunications" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_WrittenCommunications" xlink:to="dei_WrittenCommunications_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_WrittenCommunications_lbl" xml:lang="en-US">Written Communications</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2021q4/dei-2021q4.xsd#dei_SolicitingMaterial" xlink:label="dei_SolicitingMaterial" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_SolicitingMaterial" xlink:to="dei_SolicitingMaterial_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_SolicitingMaterial_lbl" xml:lang="en-US">Soliciting Material</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2021q4/dei-2021q4.xsd#dei_PreCommencementTenderOffer" xlink:label="dei_PreCommencementTenderOffer" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_PreCommencementTenderOffer" xlink:to="dei_PreCommencementTenderOffer_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_PreCommencementTenderOffer_lbl" xml:lang="en-US">Pre-commencement Tender Offer</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2021q4/dei-2021q4.xsd#dei_PreCommencementIssuerTenderOffer" xlink:label="dei_PreCommencementIssuerTenderOffer" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_PreCommencementIssuerTenderOffer" xlink:to="dei_PreCommencementIssuerTenderOffer_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_PreCommencementIssuerTenderOffer_lbl" xml:lang="en-US">Pre-commencement Issuer Tender Offer</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2021q4/dei-2021q4.xsd#dei_Security12bTitle" xlink:label="dei_Security12bTitle" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_Security12bTitle" xlink:to="dei_Security12bTitle_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_Security12bTitle_lbl" xml:lang="en-US">Title of 12(b) Security</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2021q4/dei-2021q4.xsd#dei_NoTradingSymbolFlag" xlink:label="dei_NoTradingSymbolFlag" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_NoTradingSymbolFlag" xlink:to="dei_NoTradingSymbolFlag_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_NoTradingSymbolFlag_lbl" xml:lang="en-US">No Trading Symbol Flag</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2021q4/dei-2021q4.xsd#dei_TradingSymbol" xlink:label="dei_TradingSymbol" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_TradingSymbol" xlink:to="dei_TradingSymbol_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_TradingSymbol_lbl" xml:lang="en-US">Trading Symbol</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2021q4/dei-2021q4.xsd#dei_SecurityExchangeName" xlink:label="dei_SecurityExchangeName" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_SecurityExchangeName" xlink:to="dei_SecurityExchangeName_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_SecurityExchangeName_lbl" xml:lang="en-US">Security Exchange Name</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2021q4/dei-2021q4.xsd#dei_Security12gTitle" xlink:label="dei_Security12gTitle" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_Security12gTitle" xlink:to="dei_Security12gTitle_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_Security12gTitle_lbl" xml:lang="en-US">Title of 12(g) Security</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2021q4/dei-2021q4.xsd#dei_SecurityReportingObligation" xlink:label="dei_SecurityReportingObligation" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_SecurityReportingObligation" xlink:to="dei_SecurityReportingObligation_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_SecurityReportingObligation_lbl" xml:lang="en-US">Security Reporting Obligation</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2021q4/dei-2021q4.xsd#dei_AnnualInformationForm" xlink:label="dei_AnnualInformationForm" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_AnnualInformationForm" xlink:to="dei_AnnualInformationForm_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_AnnualInformationForm_lbl" xml:lang="en-US">Annual Information Form</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2021q4/dei-2021q4.xsd#dei_AuditedAnnualFinancialStatements" xlink:label="dei_AuditedAnnualFinancialStatements" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_AuditedAnnualFinancialStatements" xlink:to="dei_AuditedAnnualFinancialStatements_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_AuditedAnnualFinancialStatements_lbl" xml:lang="en-US">Audited Annual Financial Statements</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2021q4/dei-2021q4.xsd#dei_EntityWellKnownSeasonedIssuer" xlink:label="dei_EntityWellKnownSeasonedIssuer" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_EntityWellKnownSeasonedIssuer" xlink:to="dei_EntityWellKnownSeasonedIssuer_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_EntityWellKnownSeasonedIssuer_lbl" xml:lang="en-US">Entity Well-known Seasoned Issuer</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2021q4/dei-2021q4.xsd#dei_EntityVoluntaryFilers" xlink:label="dei_EntityVoluntaryFilers" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_EntityVoluntaryFilers" xlink:to="dei_EntityVoluntaryFilers_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_EntityVoluntaryFilers_lbl" xml:lang="en-US">Entity Voluntary Filers</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2021q4/dei-2021q4.xsd#dei_EntityCurrentReportingStatus" xlink:label="dei_EntityCurrentReportingStatus" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_EntityCurrentReportingStatus" xlink:to="dei_EntityCurrentReportingStatus_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_EntityCurrentReportingStatus_lbl" xml:lang="en-US">Entity Current Reporting Status</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2021q4/dei-2021q4.xsd#dei_EntityInteractiveDataCurrent" xlink:label="dei_EntityInteractiveDataCurrent" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_EntityInteractiveDataCurrent" xlink:to="dei_EntityInteractiveDataCurrent_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_EntityInteractiveDataCurrent_lbl" xml:lang="en-US">Entity Interactive Data Current</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2021q4/dei-2021q4.xsd#dei_EntityFilerCategory" xlink:label="dei_EntityFilerCategory" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_EntityFilerCategory" xlink:to="dei_EntityFilerCategory_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_EntityFilerCategory_lbl" xml:lang="en-US">Entity Filer Category</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2021q4/dei-2021q4.xsd#dei_EntitySmallBusiness" xlink:label="dei_EntitySmallBusiness" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_EntitySmallBusiness" xlink:to="dei_EntitySmallBusiness_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_EntitySmallBusiness_lbl" xml:lang="en-US">Entity Small Business</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2021q4/dei-2021q4.xsd#dei_EntityEmergingGrowthCompany" xlink:label="dei_EntityEmergingGrowthCompany" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_EntityEmergingGrowthCompany" xlink:to="dei_EntityEmergingGrowthCompany_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_EntityEmergingGrowthCompany_lbl" xml:lang="en-US">Entity Emerging Growth Company</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2021q4/dei-2021q4.xsd#dei_EntityExTransitionPeriod" xlink:label="dei_EntityExTransitionPeriod" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_EntityExTransitionPeriod" xlink:to="dei_EntityExTransitionPeriod_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_EntityExTransitionPeriod_lbl" xml:lang="en-US">Elected Not To Use the Extended Transition Period</link:label>
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2021q4/dei-2021q4.xsd#dei_DocumentAccountingStandard" xlink:label="dei_DocumentAccountingStandard" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_DocumentAccountingStandard" xlink:to="dei_DocumentAccountingStandard_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_DocumentAccountingStandard_lbl" xml:lang="en-US">Document Accounting Standard</link:label>
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<DOCUMENT>
<TYPE>EX-101.PRE
<SEQUENCE>5
<FILENAME>mrsn-20221107_pre.xml
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<TYPE>XML
<SEQUENCE>6
<FILENAME>R1.htm
<DESCRIPTION>IDEA: XBRL DOCUMENT
<TEXT>
<html>
<head>
<title></title>
<link rel="stylesheet" type="text/css" href="include/report.css">
<script type="text/javascript" src="Show.js">/* Do Not Remove This Comment */</script><script type="text/javascript">
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<span style="display: none;">v3.22.2.2</span><table class="report" border="0" cellspacing="2" id="idm139729053492032">
<tr>
<th class="tl" colspan="1" rowspan="1"><div style="width: 200px;"><strong>Cover<br></strong></div></th>
<th class="th"><div>Nov. 07, 2022</div></th>
</tr>
<tr class="re">
<td class="pl" style="border-bottom: 0px;" valign="top"><a class="a" href="javascript:void(0);" onclick="Show.showAR( this, 'defref_dei_CoverAbstract', window );"><strong>Cover [Abstract]</strong></a></td>
<td class="text">&#160;<span></span>
</td>
</tr>
<tr class="ro">
<td class="pl" style="border-bottom: 0px;" valign="top"><a class="a" href="javascript:void(0);" onclick="Show.showAR( this, 'defref_dei_DocumentType', window );">Document Type</a></td>
<td class="text">8-K<span></span>
</td>
</tr>
<tr class="re">
<td class="pl" style="border-bottom: 0px;" valign="top"><a class="a" href="javascript:void(0);" onclick="Show.showAR( this, 'defref_dei_AmendmentFlag', window );">Amendment Flag</a></td>
<td class="text">false<span></span>
</td>
</tr>
<tr class="ro">
<td class="pl" style="border-bottom: 0px;" valign="top"><a class="a" href="javascript:void(0);" onclick="Show.showAR( this, 'defref_dei_DocumentPeriodEndDate', window );">Document Period End Date</a></td>
<td class="text">Nov.  07,  2022<span></span>
</td>
</tr>
<tr class="re">
<td class="pl" style="border-bottom: 0px;" valign="top"><a class="a" href="javascript:void(0);" onclick="Show.showAR( this, 'defref_dei_EntityFileNumber', window );">Entity File Number</a></td>
<td class="text">001-38129<span></span>
</td>
</tr>
<tr class="ro">
<td class="pl" style="border-bottom: 0px;" valign="top"><a class="a" href="javascript:void(0);" onclick="Show.showAR( this, 'defref_dei_EntityRegistrantName', window );">Entity Registrant Name</a></td>
<td class="text">MERSANA THERAPEUTICS, INC.<span></span>
</td>
</tr>
<tr class="re">
<td class="pl" style="border-bottom: 0px;" valign="top"><a class="a" href="javascript:void(0);" onclick="Show.showAR( this, 'defref_dei_EntityCentralIndexKey', window );">Entity Central Index Key</a></td>
<td class="text">0001442836<span></span>
</td>
</tr>
<tr class="ro">
<td class="pl" style="border-bottom: 0px;" valign="top"><a class="a" href="javascript:void(0);" onclick="Show.showAR( this, 'defref_dei_EntityTaxIdentificationNumber', window );">Entity Tax Identification Number</a></td>
<td class="text">04-3562403<span></span>
</td>
</tr>
<tr class="re">
<td class="pl" style="border-bottom: 0px;" valign="top"><a class="a" href="javascript:void(0);" onclick="Show.showAR( this, 'defref_dei_EntityIncorporationStateCountryCode', window );">Entity Incorporation, State or Country Code</a></td>
<td class="text">DE<span></span>
</td>
</tr>
<tr class="ro">
<td class="pl" style="border-bottom: 0px;" valign="top"><a class="a" href="javascript:void(0);" onclick="Show.showAR( this, 'defref_dei_EntityAddressAddressLine1', window );">Entity Address, Address Line One</a></td>
<td class="text">840
Memorial Drive<span></span>
</td>
</tr>
<tr class="re">
<td class="pl" style="border-bottom: 0px;" valign="top"><a class="a" href="javascript:void(0);" onclick="Show.showAR( this, 'defref_dei_EntityAddressCityOrTown', window );">Entity Address, City or Town</a></td>
<td class="text">Cambridge<span></span>
</td>
</tr>
<tr class="ro">
<td class="pl" style="border-bottom: 0px;" valign="top"><a class="a" href="javascript:void(0);" onclick="Show.showAR( this, 'defref_dei_EntityAddressStateOrProvince', window );">Entity Address, State or Province</a></td>
<td class="text">MA<span></span>
</td>
</tr>
<tr class="re">
<td class="pl" style="border-bottom: 0px;" valign="top"><a class="a" href="javascript:void(0);" onclick="Show.showAR( this, 'defref_dei_EntityAddressPostalZipCode', window );">Entity Address, Postal Zip Code</a></td>
<td class="text">02139<span></span>
</td>
</tr>
<tr class="ro">
<td class="pl" style="border-bottom: 0px;" valign="top"><a class="a" href="javascript:void(0);" onclick="Show.showAR( this, 'defref_dei_CityAreaCode', window );">City Area Code</a></td>
<td class="text">617<span></span>
</td>
</tr>
<tr class="re">
<td class="pl" style="border-bottom: 0px;" valign="top"><a class="a" href="javascript:void(0);" onclick="Show.showAR( this, 'defref_dei_LocalPhoneNumber', window );">Local Phone Number</a></td>
<td class="text">498-0020<span></span>
</td>
</tr>
<tr class="ro">
<td class="pl" style="border-bottom: 0px;" valign="top"><a class="a" href="javascript:void(0);" onclick="Show.showAR( this, 'defref_dei_WrittenCommunications', window );">Written Communications</a></td>
<td class="text">false<span></span>
</td>
</tr>
<tr class="re">
<td class="pl" style="border-bottom: 0px;" valign="top"><a class="a" href="javascript:void(0);" onclick="Show.showAR( this, 'defref_dei_SolicitingMaterial', window );">Soliciting Material</a></td>
<td class="text">false<span></span>
</td>
</tr>
<tr class="ro">
<td class="pl" style="border-bottom: 0px;" valign="top"><a class="a" href="javascript:void(0);" onclick="Show.showAR( this, 'defref_dei_PreCommencementTenderOffer', window );">Pre-commencement Tender Offer</a></td>
<td class="text">false<span></span>
</td>
</tr>
<tr class="re">
<td class="pl" style="border-bottom: 0px;" valign="top"><a class="a" href="javascript:void(0);" onclick="Show.showAR( this, 'defref_dei_PreCommencementIssuerTenderOffer', window );">Pre-commencement Issuer Tender Offer</a></td>
<td class="text">false<span></span>
</td>
</tr>
<tr class="ro">
<td class="pl" style="border-bottom: 0px;" valign="top"><a class="a" href="javascript:void(0);" onclick="Show.showAR( this, 'defref_dei_Security12bTitle', window );">Title of 12(b) Security</a></td>
<td class="text">Common Stock, $0.0001 par value<span></span>
</td>
</tr>
<tr class="re">
<td class="pl" style="border-bottom: 0px;" valign="top"><a class="a" href="javascript:void(0);" onclick="Show.showAR( this, 'defref_dei_TradingSymbol', window );">Trading Symbol</a></td>
<td class="text">MRSN<span></span>
</td>
</tr>
<tr class="ro">
<td class="pl" style="border-bottom: 0px;" valign="top"><a class="a" href="javascript:void(0);" onclick="Show.showAR( this, 'defref_dei_SecurityExchangeName', window );">Security Exchange Name</a></td>
<td class="text">NASDAQ<span></span>
</td>
</tr>
<tr class="re">
<td class="pl" style="border-bottom: 0px;" valign="top"><a class="a" href="javascript:void(0);" onclick="Show.showAR( this, 'defref_dei_EntityEmergingGrowthCompany', window );">Entity Emerging Growth Company</a></td>
<td class="text">false<span></span>
</td>
</tr>
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<div style="display: none;">
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<tr><td class="hide"><a style="color: white;" href="javascript:void(0);" onclick="Show.hideAR();">X</a></td></tr>
<tr><td><div class="body" style="padding: 2px;">
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">- Definition</a><div><p>Boolean flag that is true when the XBRL content amends previously-filed or accepted submission.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ References</a><div style="display: none;"><p>No definition available.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ Details</a><div style="display: none;"><table border="0" cellpadding="0" cellspacing="0">
<tr>
<td><strong> Name:</strong></td>
<td style="white-space:nowrap;">dei_AmendmentFlag</td>
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<td>xbrli:booleanItemType</td>
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<td><strong> Balance Type:</strong></td>
<td>na</td>
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<td><strong> Period Type:</strong></td>
<td>duration</td>
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</table></div>
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<tr><td class="hide"><a style="color: white;" href="javascript:void(0);" onclick="Show.hideAR();">X</a></td></tr>
<tr><td><div class="body" style="padding: 2px;">
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">- Definition</a><div><p>Area code of city</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ References</a><div style="display: none;"><p>No definition available.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ Details</a><div style="display: none;"><table border="0" cellpadding="0" cellspacing="0">
<tr>
<td><strong> Name:</strong></td>
<td style="white-space:nowrap;">dei_CityAreaCode</td>
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<tr>
<td style="padding-right: 4px;white-space:nowrap;"><strong> Namespace Prefix:</strong></td>
<td>dei_</td>
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<td><strong> Data Type:</strong></td>
<td>xbrli:normalizedStringItemType</td>
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<td><strong> Balance Type:</strong></td>
<td>na</td>
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<td><strong> Period Type:</strong></td>
<td>duration</td>
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<table border="0" cellpadding="0" cellspacing="0" class="authRefData" style="display: none;" id="defref_dei_CoverAbstract">
<tr><td class="hide"><a style="color: white;" href="javascript:void(0);" onclick="Show.hideAR();">X</a></td></tr>
<tr><td><div class="body" style="padding: 2px;">
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">- Definition</a><div><p>Cover page.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ References</a><div style="display: none;"><p>No definition available.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ Details</a><div style="display: none;"><table border="0" cellpadding="0" cellspacing="0">
<tr>
<td><strong> Name:</strong></td>
<td style="white-space:nowrap;">dei_CoverAbstract</td>
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<td style="padding-right: 4px;white-space:nowrap;"><strong> Namespace Prefix:</strong></td>
<td>dei_</td>
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<td>xbrli:stringItemType</td>
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<td><strong> Balance Type:</strong></td>
<td>na</td>
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<td><strong> Period Type:</strong></td>
<td>duration</td>
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<tr><td class="hide"><a style="color: white;" href="javascript:void(0);" onclick="Show.hideAR();">X</a></td></tr>
<tr><td><div class="body" style="padding: 2px;">
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">- Definition</a><div><p>For the EDGAR submission types of Form 8-K: the date of the report, the date of the earliest event reported; for the EDGAR submission types of Form N-1A: the filing date; for all other submission types: the end of the reporting or transition period.  The format of the date is YYYY-MM-DD.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ References</a><div style="display: none;"><p>No definition available.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ Details</a><div style="display: none;"><table border="0" cellpadding="0" cellspacing="0">
<tr>
<td><strong> Name:</strong></td>
<td style="white-space:nowrap;">dei_DocumentPeriodEndDate</td>
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<td>dei_</td>
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<td>xbrli:dateItemType</td>
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<td>na</td>
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<td><strong> Period Type:</strong></td>
<td>duration</td>
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<tr><td class="hide"><a style="color: white;" href="javascript:void(0);" onclick="Show.hideAR();">X</a></td></tr>
<tr><td><div class="body" style="padding: 2px;">
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">- Definition</a><div><p>The type of document being provided (such as 10-K, 10-Q, 485BPOS, etc). The document type is limited to the same value as the supporting SEC submission type, or the word 'Other'.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ References</a><div style="display: none;"><p>No definition available.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ Details</a><div style="display: none;"><table border="0" cellpadding="0" cellspacing="0">
<tr>
<td><strong> Name:</strong></td>
<td style="white-space:nowrap;">dei_DocumentType</td>
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<td style="padding-right: 4px;white-space:nowrap;"><strong> Namespace Prefix:</strong></td>
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<td>dei:submissionTypeItemType</td>
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<td><strong> Balance Type:</strong></td>
<td>na</td>
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<td><strong> Period Type:</strong></td>
<td>duration</td>
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<tr><td class="hide"><a style="color: white;" href="javascript:void(0);" onclick="Show.hideAR();">X</a></td></tr>
<tr><td><div class="body" style="padding: 2px;">
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">- Definition</a><div><p>Address Line 1 such as Attn, Building Name, Street Name</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ References</a><div style="display: none;"><p>No definition available.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ Details</a><div style="display: none;"><table border="0" cellpadding="0" cellspacing="0">
<tr>
<td><strong> Name:</strong></td>
<td style="white-space:nowrap;">dei_EntityAddressAddressLine1</td>
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<td style="padding-right: 4px;white-space:nowrap;"><strong> Namespace Prefix:</strong></td>
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<td>xbrli:normalizedStringItemType</td>
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<td><strong> Balance Type:</strong></td>
<td>na</td>
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<td><strong> Period Type:</strong></td>
<td>duration</td>
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<tr><td class="hide"><a style="color: white;" href="javascript:void(0);" onclick="Show.hideAR();">X</a></td></tr>
<tr><td><div class="body" style="padding: 2px;">
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">- Definition</a><div><p>Name of the City or Town</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ References</a><div style="display: none;"><p>No definition available.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ Details</a><div style="display: none;"><table border="0" cellpadding="0" cellspacing="0">
<tr>
<td><strong> Name:</strong></td>
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<tr>
<td style="padding-right: 4px;white-space:nowrap;"><strong> Namespace Prefix:</strong></td>
<td>dei_</td>
</tr>
<tr>
<td><strong> Data Type:</strong></td>
<td>xbrli:normalizedStringItemType</td>
</tr>
<tr>
<td><strong> Balance Type:</strong></td>
<td>na</td>
</tr>
<tr>
<td><strong> Period Type:</strong></td>
<td>duration</td>
</tr>
</table></div>
</div></td></tr>
</table>
<table border="0" cellpadding="0" cellspacing="0" class="authRefData" style="display: none;" id="defref_dei_EntityAddressPostalZipCode">
<tr><td class="hide"><a style="color: white;" href="javascript:void(0);" onclick="Show.hideAR();">X</a></td></tr>
<tr><td><div class="body" style="padding: 2px;">
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">- Definition</a><div><p>Code for the postal or zip code</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ References</a><div style="display: none;"><p>No definition available.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ Details</a><div style="display: none;"><table border="0" cellpadding="0" cellspacing="0">
<tr>
<td><strong> Name:</strong></td>
<td style="white-space:nowrap;">dei_EntityAddressPostalZipCode</td>
</tr>
<tr>
<td style="padding-right: 4px;white-space:nowrap;"><strong> Namespace Prefix:</strong></td>
<td>dei_</td>
</tr>
<tr>
<td><strong> Data Type:</strong></td>
<td>xbrli:normalizedStringItemType</td>
</tr>
<tr>
<td><strong> Balance Type:</strong></td>
<td>na</td>
</tr>
<tr>
<td><strong> Period Type:</strong></td>
<td>duration</td>
</tr>
</table></div>
</div></td></tr>
</table>
<table border="0" cellpadding="0" cellspacing="0" class="authRefData" style="display: none;" id="defref_dei_EntityAddressStateOrProvince">
<tr><td class="hide"><a style="color: white;" href="javascript:void(0);" onclick="Show.hideAR();">X</a></td></tr>
<tr><td><div class="body" style="padding: 2px;">
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">- Definition</a><div><p>Name of the state or province.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ References</a><div style="display: none;"><p>No definition available.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ Details</a><div style="display: none;"><table border="0" cellpadding="0" cellspacing="0">
<tr>
<td><strong> Name:</strong></td>
<td style="white-space:nowrap;">dei_EntityAddressStateOrProvince</td>
</tr>
<tr>
<td style="padding-right: 4px;white-space:nowrap;"><strong> Namespace Prefix:</strong></td>
<td>dei_</td>
</tr>
<tr>
<td><strong> Data Type:</strong></td>
<td>dei:stateOrProvinceItemType</td>
</tr>
<tr>
<td><strong> Balance Type:</strong></td>
<td>na</td>
</tr>
<tr>
<td><strong> Period Type:</strong></td>
<td>duration</td>
</tr>
</table></div>
</div></td></tr>
</table>
<table border="0" cellpadding="0" cellspacing="0" class="authRefData" style="display: none;" id="defref_dei_EntityCentralIndexKey">
<tr><td class="hide"><a style="color: white;" href="javascript:void(0);" onclick="Show.hideAR();">X</a></td></tr>
<tr><td><div class="body" style="padding: 2px;">
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">- Definition</a><div><p>A unique 10-digit SEC-issued value to identify entities that have filed disclosures with the SEC. It is commonly abbreviated as CIK.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ References</a><div style="display: none;"><p>Reference 1: http://www.xbrl.org/2003/role/presentationRef<br> -Publisher SEC<br> -Name Exchange Act<br> -Number 240<br> -Section 12<br> -Subsection b-2<br></p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ Details</a><div style="display: none;"><table border="0" cellpadding="0" cellspacing="0">
<tr>
<td><strong> Name:</strong></td>
<td style="white-space:nowrap;">dei_EntityCentralIndexKey</td>
</tr>
<tr>
<td style="padding-right: 4px;white-space:nowrap;"><strong> Namespace Prefix:</strong></td>
<td>dei_</td>
</tr>
<tr>
<td><strong> Data Type:</strong></td>
<td>dei:centralIndexKeyItemType</td>
</tr>
<tr>
<td><strong> Balance Type:</strong></td>
<td>na</td>
</tr>
<tr>
<td><strong> Period Type:</strong></td>
<td>duration</td>
</tr>
</table></div>
</div></td></tr>
</table>
<table border="0" cellpadding="0" cellspacing="0" class="authRefData" style="display: none;" id="defref_dei_EntityEmergingGrowthCompany">
<tr><td class="hide"><a style="color: white;" href="javascript:void(0);" onclick="Show.hideAR();">X</a></td></tr>
<tr><td><div class="body" style="padding: 2px;">
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">- Definition</a><div><p>Indicate if registrant meets the emerging growth company criteria.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ References</a><div style="display: none;"><p>Reference 1: http://www.xbrl.org/2003/role/presentationRef<br> -Publisher SEC<br> -Name Exchange Act<br> -Number 240<br> -Section 12<br> -Subsection b-2<br></p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ Details</a><div style="display: none;"><table border="0" cellpadding="0" cellspacing="0">
<tr>
<td><strong> Name:</strong></td>
<td style="white-space:nowrap;">dei_EntityEmergingGrowthCompany</td>
</tr>
<tr>
<td style="padding-right: 4px;white-space:nowrap;"><strong> Namespace Prefix:</strong></td>
<td>dei_</td>
</tr>
<tr>
<td><strong> Data Type:</strong></td>
<td>xbrli:booleanItemType</td>
</tr>
<tr>
<td><strong> Balance Type:</strong></td>
<td>na</td>
</tr>
<tr>
<td><strong> Period Type:</strong></td>
<td>duration</td>
</tr>
</table></div>
</div></td></tr>
</table>
<table border="0" cellpadding="0" cellspacing="0" class="authRefData" style="display: none;" id="defref_dei_EntityFileNumber">
<tr><td class="hide"><a style="color: white;" href="javascript:void(0);" onclick="Show.hideAR();">X</a></td></tr>
<tr><td><div class="body" style="padding: 2px;">
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">- Definition</a><div><p>Commission file number. The field allows up to 17 characters. The prefix may contain 1-3 digits, the sequence number may contain 1-8 digits, the optional suffix may contain 1-4 characters, and the fields are separated with a hyphen.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ References</a><div style="display: none;"><p>No definition available.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ Details</a><div style="display: none;"><table border="0" cellpadding="0" cellspacing="0">
<tr>
<td><strong> Name:</strong></td>
<td style="white-space:nowrap;">dei_EntityFileNumber</td>
</tr>
<tr>
<td style="padding-right: 4px;white-space:nowrap;"><strong> Namespace Prefix:</strong></td>
<td>dei_</td>
</tr>
<tr>
<td><strong> Data Type:</strong></td>
<td>dei:fileNumberItemType</td>
</tr>
<tr>
<td><strong> Balance Type:</strong></td>
<td>na</td>
</tr>
<tr>
<td><strong> Period Type:</strong></td>
<td>duration</td>
</tr>
</table></div>
</div></td></tr>
</table>
<table border="0" cellpadding="0" cellspacing="0" class="authRefData" style="display: none;" id="defref_dei_EntityIncorporationStateCountryCode">
<tr><td class="hide"><a style="color: white;" href="javascript:void(0);" onclick="Show.hideAR();">X</a></td></tr>
<tr><td><div class="body" style="padding: 2px;">
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">- Definition</a><div><p>Two-character EDGAR code representing the state or country of incorporation.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ References</a><div style="display: none;"><p>No definition available.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ Details</a><div style="display: none;"><table border="0" cellpadding="0" cellspacing="0">
<tr>
<td><strong> Name:</strong></td>
<td style="white-space:nowrap;">dei_EntityIncorporationStateCountryCode</td>
</tr>
<tr>
<td style="padding-right: 4px;white-space:nowrap;"><strong> Namespace Prefix:</strong></td>
<td>dei_</td>
</tr>
<tr>
<td><strong> Data Type:</strong></td>
<td>dei:edgarStateCountryItemType</td>
</tr>
<tr>
<td><strong> Balance Type:</strong></td>
<td>na</td>
</tr>
<tr>
<td><strong> Period Type:</strong></td>
<td>duration</td>
</tr>
</table></div>
</div></td></tr>
</table>
<table border="0" cellpadding="0" cellspacing="0" class="authRefData" style="display: none;" id="defref_dei_EntityRegistrantName">
<tr><td class="hide"><a style="color: white;" href="javascript:void(0);" onclick="Show.hideAR();">X</a></td></tr>
<tr><td><div class="body" style="padding: 2px;">
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">- Definition</a><div><p>The exact name of the entity filing the report as specified in its charter, which is required by forms filed with the SEC.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ References</a><div style="display: none;"><p>Reference 1: http://www.xbrl.org/2003/role/presentationRef<br> -Publisher SEC<br> -Name Exchange Act<br> -Number 240<br> -Section 12<br> -Subsection b-2<br></p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ Details</a><div style="display: none;"><table border="0" cellpadding="0" cellspacing="0">
<tr>
<td><strong> Name:</strong></td>
<td style="white-space:nowrap;">dei_EntityRegistrantName</td>
</tr>
<tr>
<td style="padding-right: 4px;white-space:nowrap;"><strong> Namespace Prefix:</strong></td>
<td>dei_</td>
</tr>
<tr>
<td><strong> Data Type:</strong></td>
<td>xbrli:normalizedStringItemType</td>
</tr>
<tr>
<td><strong> Balance Type:</strong></td>
<td>na</td>
</tr>
<tr>
<td><strong> Period Type:</strong></td>
<td>duration</td>
</tr>
</table></div>
</div></td></tr>
</table>
<table border="0" cellpadding="0" cellspacing="0" class="authRefData" style="display: none;" id="defref_dei_EntityTaxIdentificationNumber">
<tr><td class="hide"><a style="color: white;" href="javascript:void(0);" onclick="Show.hideAR();">X</a></td></tr>
<tr><td><div class="body" style="padding: 2px;">
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">- Definition</a><div><p>The Tax Identification Number (TIN), also known as an Employer Identification Number (EIN), is a unique 9-digit value assigned by the IRS.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ References</a><div style="display: none;"><p>Reference 1: http://www.xbrl.org/2003/role/presentationRef<br> -Publisher SEC<br> -Name Exchange Act<br> -Number 240<br> -Section 12<br> -Subsection b-2<br></p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ Details</a><div style="display: none;"><table border="0" cellpadding="0" cellspacing="0">
<tr>
<td><strong> Name:</strong></td>
<td style="white-space:nowrap;">dei_EntityTaxIdentificationNumber</td>
</tr>
<tr>
<td style="padding-right: 4px;white-space:nowrap;"><strong> Namespace Prefix:</strong></td>
<td>dei_</td>
</tr>
<tr>
<td><strong> Data Type:</strong></td>
<td>dei:employerIdItemType</td>
</tr>
<tr>
<td><strong> Balance Type:</strong></td>
<td>na</td>
</tr>
<tr>
<td><strong> Period Type:</strong></td>
<td>duration</td>
</tr>
</table></div>
</div></td></tr>
</table>
<table border="0" cellpadding="0" cellspacing="0" class="authRefData" style="display: none;" id="defref_dei_LocalPhoneNumber">
<tr><td class="hide"><a style="color: white;" href="javascript:void(0);" onclick="Show.hideAR();">X</a></td></tr>
<tr><td><div class="body" style="padding: 2px;">
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">- Definition</a><div><p>Local phone number for entity.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ References</a><div style="display: none;"><p>No definition available.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ Details</a><div style="display: none;"><table border="0" cellpadding="0" cellspacing="0">
<tr>
<td><strong> Name:</strong></td>
<td style="white-space:nowrap;">dei_LocalPhoneNumber</td>
</tr>
<tr>
<td style="padding-right: 4px;white-space:nowrap;"><strong> Namespace Prefix:</strong></td>
<td>dei_</td>
</tr>
<tr>
<td><strong> Data Type:</strong></td>
<td>xbrli:normalizedStringItemType</td>
</tr>
<tr>
<td><strong> Balance Type:</strong></td>
<td>na</td>
</tr>
<tr>
<td><strong> Period Type:</strong></td>
<td>duration</td>
</tr>
</table></div>
</div></td></tr>
</table>
<table border="0" cellpadding="0" cellspacing="0" class="authRefData" style="display: none;" id="defref_dei_PreCommencementIssuerTenderOffer">
<tr><td class="hide"><a style="color: white;" href="javascript:void(0);" onclick="Show.hideAR();">X</a></td></tr>
<tr><td><div class="body" style="padding: 2px;">
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">- Definition</a><div><p>Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ References</a><div style="display: none;"><p>Reference 1: http://www.xbrl.org/2003/role/presentationRef<br> -Publisher SEC<br> -Name Exchange Act<br> -Number 240<br> -Section 13e<br> -Subsection 4c<br></p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ Details</a><div style="display: none;"><table border="0" cellpadding="0" cellspacing="0">
<tr>
<td><strong> Name:</strong></td>
<td style="white-space:nowrap;">dei_PreCommencementIssuerTenderOffer</td>
</tr>
<tr>
<td style="padding-right: 4px;white-space:nowrap;"><strong> Namespace Prefix:</strong></td>
<td>dei_</td>
</tr>
<tr>
<td><strong> Data Type:</strong></td>
<td>xbrli:booleanItemType</td>
</tr>
<tr>
<td><strong> Balance Type:</strong></td>
<td>na</td>
</tr>
<tr>
<td><strong> Period Type:</strong></td>
<td>duration</td>
</tr>
</table></div>
</div></td></tr>
</table>
<table border="0" cellpadding="0" cellspacing="0" class="authRefData" style="display: none;" id="defref_dei_PreCommencementTenderOffer">
<tr><td class="hide"><a style="color: white;" href="javascript:void(0);" onclick="Show.hideAR();">X</a></td></tr>
<tr><td><div class="body" style="padding: 2px;">
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">- Definition</a><div><p>Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ References</a><div style="display: none;"><p>Reference 1: http://www.xbrl.org/2003/role/presentationRef<br> -Publisher SEC<br> -Name Exchange Act<br> -Number 240<br> -Section 14d<br> -Subsection 2b<br></p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ Details</a><div style="display: none;"><table border="0" cellpadding="0" cellspacing="0">
<tr>
<td><strong> Name:</strong></td>
<td style="white-space:nowrap;">dei_PreCommencementTenderOffer</td>
</tr>
<tr>
<td style="padding-right: 4px;white-space:nowrap;"><strong> Namespace Prefix:</strong></td>
<td>dei_</td>
</tr>
<tr>
<td><strong> Data Type:</strong></td>
<td>xbrli:booleanItemType</td>
</tr>
<tr>
<td><strong> Balance Type:</strong></td>
<td>na</td>
</tr>
<tr>
<td><strong> Period Type:</strong></td>
<td>duration</td>
</tr>
</table></div>
</div></td></tr>
</table>
<table border="0" cellpadding="0" cellspacing="0" class="authRefData" style="display: none;" id="defref_dei_Security12bTitle">
<tr><td class="hide"><a style="color: white;" href="javascript:void(0);" onclick="Show.hideAR();">X</a></td></tr>
<tr><td><div class="body" style="padding: 2px;">
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">- Definition</a><div><p>Title of a 12(b) registered security.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ References</a><div style="display: none;"><p>Reference 1: http://www.xbrl.org/2003/role/presentationRef<br> -Publisher SEC<br> -Name Exchange Act<br> -Number 240<br> -Section 12<br> -Subsection b<br></p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ Details</a><div style="display: none;"><table border="0" cellpadding="0" cellspacing="0">
<tr>
<td><strong> Name:</strong></td>
<td style="white-space:nowrap;">dei_Security12bTitle</td>
</tr>
<tr>
<td style="padding-right: 4px;white-space:nowrap;"><strong> Namespace Prefix:</strong></td>
<td>dei_</td>
</tr>
<tr>
<td><strong> Data Type:</strong></td>
<td>dei:securityTitleItemType</td>
</tr>
<tr>
<td><strong> Balance Type:</strong></td>
<td>na</td>
</tr>
<tr>
<td><strong> Period Type:</strong></td>
<td>duration</td>
</tr>
</table></div>
</div></td></tr>
</table>
<table border="0" cellpadding="0" cellspacing="0" class="authRefData" style="display: none;" id="defref_dei_SecurityExchangeName">
<tr><td class="hide"><a style="color: white;" href="javascript:void(0);" onclick="Show.hideAR();">X</a></td></tr>
<tr><td><div class="body" style="padding: 2px;">
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">- Definition</a><div><p>Name of the Exchange on which a security is registered.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ References</a><div style="display: none;"><p>Reference 1: http://www.xbrl.org/2003/role/presentationRef<br> -Publisher SEC<br> -Name Exchange Act<br> -Number 240<br> -Section 12<br> -Subsection d1-1<br></p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ Details</a><div style="display: none;"><table border="0" cellpadding="0" cellspacing="0">
<tr>
<td><strong> Name:</strong></td>
<td style="white-space:nowrap;">dei_SecurityExchangeName</td>
</tr>
<tr>
<td style="padding-right: 4px;white-space:nowrap;"><strong> Namespace Prefix:</strong></td>
<td>dei_</td>
</tr>
<tr>
<td><strong> Data Type:</strong></td>
<td>dei:edgarExchangeCodeItemType</td>
</tr>
<tr>
<td><strong> Balance Type:</strong></td>
<td>na</td>
</tr>
<tr>
<td><strong> Period Type:</strong></td>
<td>duration</td>
</tr>
</table></div>
</div></td></tr>
</table>
<table border="0" cellpadding="0" cellspacing="0" class="authRefData" style="display: none;" id="defref_dei_SolicitingMaterial">
<tr><td class="hide"><a style="color: white;" href="javascript:void(0);" onclick="Show.hideAR();">X</a></td></tr>
<tr><td><div class="body" style="padding: 2px;">
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">- Definition</a><div><p>Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as soliciting material pursuant to Rule 14a-12 under the Exchange Act.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ References</a><div style="display: none;"><p>Reference 1: http://www.xbrl.org/2003/role/presentationRef<br> -Publisher SEC<br> -Name Exchange Act<br> -Section 14a<br> -Number 240<br> -Subsection 12<br></p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ Details</a><div style="display: none;"><table border="0" cellpadding="0" cellspacing="0">
<tr>
<td><strong> Name:</strong></td>
<td style="white-space:nowrap;">dei_SolicitingMaterial</td>
</tr>
<tr>
<td style="padding-right: 4px;white-space:nowrap;"><strong> Namespace Prefix:</strong></td>
<td>dei_</td>
</tr>
<tr>
<td><strong> Data Type:</strong></td>
<td>xbrli:booleanItemType</td>
</tr>
<tr>
<td><strong> Balance Type:</strong></td>
<td>na</td>
</tr>
<tr>
<td><strong> Period Type:</strong></td>
<td>duration</td>
</tr>
</table></div>
</div></td></tr>
</table>
<table border="0" cellpadding="0" cellspacing="0" class="authRefData" style="display: none;" id="defref_dei_TradingSymbol">
<tr><td class="hide"><a style="color: white;" href="javascript:void(0);" onclick="Show.hideAR();">X</a></td></tr>
<tr><td><div class="body" style="padding: 2px;">
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">- Definition</a><div><p>Trading symbol of an instrument as listed on an exchange.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ References</a><div style="display: none;"><p>No definition available.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ Details</a><div style="display: none;"><table border="0" cellpadding="0" cellspacing="0">
<tr>
<td><strong> Name:</strong></td>
<td style="white-space:nowrap;">dei_TradingSymbol</td>
</tr>
<tr>
<td style="padding-right: 4px;white-space:nowrap;"><strong> Namespace Prefix:</strong></td>
<td>dei_</td>
</tr>
<tr>
<td><strong> Data Type:</strong></td>
<td>dei:tradingSymbolItemType</td>
</tr>
<tr>
<td><strong> Balance Type:</strong></td>
<td>na</td>
</tr>
<tr>
<td><strong> Period Type:</strong></td>
<td>duration</td>
</tr>
</table></div>
</div></td></tr>
</table>
<table border="0" cellpadding="0" cellspacing="0" class="authRefData" style="display: none;" id="defref_dei_WrittenCommunications">
<tr><td class="hide"><a style="color: white;" href="javascript:void(0);" onclick="Show.hideAR();">X</a></td></tr>
<tr><td><div class="body" style="padding: 2px;">
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">- Definition</a><div><p>Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as written communications pursuant to Rule 425 under the Securities Act.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ References</a><div style="display: none;"><p>Reference 1: http://www.xbrl.org/2003/role/presentationRef<br> -Publisher SEC<br> -Name Securities Act<br> -Number 230<br> -Section 425<br></p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ Details</a><div style="display: none;"><table border="0" cellpadding="0" cellspacing="0">
<tr>
<td><strong> Name:</strong></td>
<td style="white-space:nowrap;">dei_WrittenCommunications</td>
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<td style="padding-right: 4px;white-space:nowrap;"><strong> Namespace Prefix:</strong></td>
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<td><strong> Data Type:</strong></td>
<td>xbrli:booleanItemType</td>
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<tr>
<td><strong> Balance Type:</strong></td>
<td>na</td>
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<tr>
<td><strong> Period Type:</strong></td>
<td>duration</td>
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  "r6": {
   "Name": "Exchange Act",
   "Number": "240",
   "Publisher": "SEC",
   "Section": "12, 13, 15d"
  },
  "r7": {
   "Name": "Exchange Act",
   "Number": "240",
   "Publisher": "SEC",
   "Section": "13e",
   "Subsection": "4c"
  },
  "r8": {
   "Name": "Exchange Act",
   "Number": "240",
   "Publisher": "SEC",
   "Section": "14d",
   "Subsection": "2b"
  },
  "r9": {
   "Name": "Exchange Act",
   "Number": "240",
   "Publisher": "SEC",
   "Section": "15",
   "Subsection": "d"
  }
 },
 "version": "2.1"
}
</TEXT>
</DOCUMENT>
<DOCUMENT>
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<FILENAME>0001104659-22-115117-xbrl.zip
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end
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
