Description of Business and Basis of Presentation	6 Months Ended
Description of Business and Basis of Presentation	Jun. 30, 2021
Accounting Policies [Abstract]
Description of Business and Basis of Presentation	Description of Business and Basis of Presentation Description of Business Exicure, Inc. (the “Company”) is a clinical-stage biotechnology company developing therapeutics for neurology, immuno-oncology, inflammatory diseases, and other genetic disorders based on its proprietary Spherical Nucleic Acid, or SNA™, technology. The Company believes that its proprietary SNA architecture has distinct chemical and biological properties that may provide advantages over other nucleic acid therapeutics and may have therapeutic potential to target diseases not typically addressed with other nucleic acid therapeutics. The Company is in preclinical development of XCUR-FXN, a lipid-nanoparticle SNA-based therapeutic candidate, for the intrathecal treatment of Friedreich’s ataxia (FA). The Company’s therapeutic candidate cavrotolimod (AST-008) is in a Phase 1b/2 clinical trial in patients with advanced solid tumors. The Company believes one of the key strengths of its proprietary SNAs is that they have the potential for increased cellular uptake compared to conventional linear oligonucleotides and as a result the potential to achieve higher efficacy at the same doses of oligonucleotide administered. The Company has shown in clinical and preclinical studies that SNAs may have therapeutic potential in immuno-oncology and dermatology. In addition, the Company has shown in preclinical studies that SNAs may have therapeutic potential in neurology, ophthalmology, pulmonology, and gastroenterology. Accordingly, the Company has expanded its pipeline into neurology, for which IND-enabling activities are ongoing for XCUR-FXN, and is concluding early stage research activities in ophthalmology, pulmonology, and gastroenterology. Throughout these unaudited condensed consolidated financial statements, the terms the “Company” and “Exicure” refer to Exicure, Inc. and its wholly owned subsidiary, Exicure Operating Company. Exicure Operating Company holds all material assets and conducts all business activities and operations of Exicure, Inc. Basis of Presentation The accompanying unaudited condensed consolidated financial statements as of June 30, 2021 and December 31, 2020, and for the six months ended June 30, 2021 and 2020, have been presented in conformity with generally accepted accounting principles in the United States (“GAAP”). Principles of Consolidation The accompanying unaudited condensed consolidated financial statements include the accounts of Exicure, Inc. and its wholly owned subsidiary, Exicure Operating Company. All intercompany transactions and accounts are eliminated in consolidation. Significant Risks and Uncertainties As discussed in Note 3, Collaborative Research and License Agreements, revenue for the three and six months ended June 30, 2021 reflects events and conditions that occurred during that period that increased the number of hours estimated to be required to complete the services under the AbbVie Collaboration Agreement. These increased estimated efforts resulted in less progress occurring relative to the increased estimate of total projected hours to complete the research services (and thus limited revenue recognized) during the three and six months ended June 30, 2021 and compared to the amount of revenue recognized in the comparable periods. Due to uncertainties inherent in the estimation process, it is at least reasonably possible that estimated efforts required to complete the research services under the AbbVie Collaboration Agreement will be further revised in the near-term. COVID-19 Risks and Uncertainties In response to the ongoing COVID-19 pandemic, the Company has taken and continues to take active measures designed to address and mitigate the impact of the COVID-19 pandemic on its business, such as remote working policies, facilitating management’s routine communication to address employee and business concerns and providing frequent updates to the Company’s board of directors (the “Board”). During the second quarter of 2021 and through the date of this report, the Company continues to operate under COVID-19 social distancing guidelines and has generally operated with approximately 100% of its R&D staff on-site. The Company’s office and general and administrative team is also working on-site approximately 50% of the time. The Company’s preclinical development program in Friedreich’s ataxia (“FA”) is ongoing and it began IND-enabling studies for XCUR-FXN in late 2020. The Company also continues to progress its collaborations with AbbVie Inc. (“AbbVie”). However, if the COVID-19 pandemic continues to persist for an extended period of time, the Company could experience further significant disruptions to its clinical and preclinical development timelines, which would adversely affect its business, financial condition, results of operations and growth prospects. The Company believes that the effects of the COVID-19 pandemic or its impact contributed to delays during the second half of 2020 and the first half of 2021 in its enrollment plans and clinical trial site start-ups for the Phase 2 dose expansion phase of the Phase 1b/2 clinical trial for its cavrotolimod (AST-008) clinical program. The Company has taken additional measures to increase the enrollment of patients, including frequent interaction with its clinical trial sites currently open as well as increasing the number of clinical trial sites that potentially are activated for this trial so that the Company may continue to enroll patients as initially planned. However, any additional delays may require the Company to further lengthen its clinical development timeline for cavrotolimod (AST-008). Pending further enrollment delays or any unanticipated effects of the COVID-19 pandemic on our clinical development plans, the Company expects to report overall response rate, or ORR, results in the first half of 2022. The extent to which the COVID-19 pandemic or its impact or effects may continue to impact the Company’s business, its clinical development and regulatory efforts, its corporate development objectives and the value of and market for its common stock, will depend on future developments that are highly uncertain and cannot be predicted with confidence at this time, such as the ultimate duration or spread of the pandemic, its impact and effects, the possibility of additional periods of increases or spikes in the number of COVID-19 cases, travel restrictions, quarantines, social distancing, phased re-openings and business closure requirements in the United States and other countries, and the effectiveness of actions taken globally to contain and treat the disease including, without limitation, the effectiveness and timing of vaccination initiatives in the United States and worldwide. The global economic slowdown, the overall disruption of global healthcare systems and the other risks and uncertainties associated with the pandemic could have a material adverse effect on the Company’s business, financial condition, results of operations and growth prospects. In addition, the Company is subject to other challenges and risks specific to its business and its ability to execute on its business plan and strategy, as well as risks and uncertainties common to companies in the biotechnology industry with research and development operations, including, without limitation, risks and uncertainties associated with: obtaining regulatory approval of its product candidates; delays or problems in obtaining clinical supply, loss of single source suppliers or failure to comply with manufacturing regulations; identifying, acquiring or in-licensing additional products or product candidates; product development and the inherent uncertainty of clinical success; and the challenges of protecting and enhancing its intellectual property rights; and the challenges of complying with applicable regulatory requirements. In addition, to the extent the ongoing COVID-19 pandemic adversely affects the Company’s business and results of operations, it may also have the effect of heightening many of the other risks and uncertainties. Liquidity Risk As of June 30, 2021, the Company has generated an accumulated deficit of $151,548 since inception and expects to incur significant expenses and negative cash flows for the foreseeable future. Based on the Company’s current operating plans, it believes that existing working capital at June 30, 2021, including the $20,000 upfront payment received in August 2021 in connection with the Ipsen Collaboration Agreement (see Note 15, Subsequent Events) and amounts borrowed and available under the MidCap Credit Facility (see Note 6, Debt), is sufficient to fund the Company’s current plans for at least the next 12 months from the date these financial statements were issued. Management believes that it will be able to obtain additional working capital through equity financings, partnerships and licensing, or other arrangements, such as its “at the market offering” program pursuant to its equity distribution agreement with BMO Capital Markets Corp., to fund its current operations and business strategy. However, there can be no assurance that such additional financing will be available and, if available, can be obtained on terms acceptable to the Company. The Company has historically principally raised capital through the sale of its securities. However, the COVID-19 pandemic continues to rapidly evolve and has already resulted in a significant disruption of global financial markets. If the disruption continues to persist and deepens, the Company could experience an inability to access additional capital, which could in the future negatively affect its ability to raise capital and ultimately, its operations. Unaudited Interim Financial Information The accompanying interim condensed consolidated balance sheet as of June 30, 2021, the interim condensed consolidated statements of operations for the three and six months ended June 30, 2021 and 2020, the interim condensed consolidated statements of comprehensive (loss) income for the three and six months ended June 30, 2021 and 2020, the interim condensed consolidated statements of changes in stockholders’ equity for the three and six months ended June 30, 2021 and 2020, and the interim condensed consolidated statements of cash flows for the six months ended June 30, 2021 and 2020, are unaudited. The interim unaudited condensed consolidated financial statements have been prepared on the same basis as the annual audited financial statements; and in the opinion of management, reflect all adjustments, which include only normal recurring adjustments necessary for the fair statement of the Company’s financial position as of June 30, 2021, the results of its operations for the three and six months ended June 30, 2021 and 2020, and the results of its cash flows for the six months ended June 30, 2021 and 2020. The financial data and other information disclosed in these notes related to the three and six months ended June 30, 2021 and 2020 are unaudited. The results for the three and six months ended June 30, 2021 are not necessarily indicative of results to be expected for the year ending December 31, 2021, or any other interim periods, or any future year or period. Use of Estimates The preparation of the financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Management bases its estimates on certain assumptions which it believes are reasonable in the circumstances and while actual results could differ from those estimates, management does not believe that any change in those assumptions in the near term would have a significant effect on the Company’s financial position, results of operations or cash flows. Actual results in future periods could differ from those estimates.