OCULAR THERAPEUTIX, INC 10-K

Item 9A. Controls and Procedures Evaluation of Disclosure Controls and Procedures Our management, with the participation of our Chief Executive Officer and Chief Financial Officer, evaluated the effectiveness of our disclosure controls and procedures as of December 31, 2022. The term “disclosure controls and procedures,” as defined in Rules 13a-15(e) and 15d-15(e) under the Securities Exchange Act of 1934, as amended, or the Exchange Act, means controls and other procedures of a company that are designed to ensure that information required to be disclosed by a company in the reports that it files or submits under the Exchange Act is recorded, processed, summarized and reported, within the time periods specified in the SEC’s rules and forms. Disclosure controls and procedures include, without limitation, controls and procedures designed to ensure that information required to be disclosed by a company in the reports that it files or submits under the Exchange Act is accumulated and communicated to the company’s management, including its principal executive and principal financial officers, as appropriate to allow timely decisions regarding required disclosure. Management, including our Chief Executive Officer and Chief Financial Officer recognizes that any controls and procedures, no matter how well designed and operated, can provide only reasonable assurance of achieving their objectives and management necessarily applies its judgment in evaluating the cost-benefit relationship of possible controls and procedures. Based on the evaluation of our disclosure controls and procedures as of December 31, 2022, our Chief Executive Officer and Chief Financial Officer concluded that, as of such date, our disclosure controls and procedures were effective at the reasonable assurance level. Management’s Annual Report on Internal Control Over Financial Reporting Our management is responsible for establishing and maintaining adequate internal control over financial reporting for Ocular Therapeutix, Inc. Internal control over financial reporting is defined in Rules 13a-15(f) and 15d-15(f) under the Exchange Act as a process designed by, or under the supervision of, the company’s principal executive and principal financial officers and effected by the company’s board of directors, management and other personnel, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for 117 Table of Contents external purposes in accordance with generally accepted accounting principles and includes those policies and procedures that: ● Pertain to the maintenance of records that in reasonable detail accurately and fairly reflect the transactions and dispositions of the assets of the company; ● Provide reasonable assurance that transactions are recorded as necessary to permit preparation of financial statements in accordance with generally accepted accounting principles, and that receipts and expenditures of the company are being made only in accordance with authorizations of management and directors of the company; and ● Provide reasonable assurance regarding prevention or timely detection of unauthorized acquisition, use or disposition of the company’s assets that could have a material effect on the financial statements. Because of its inherent limitations, internal control over financial reporting may not prevent or detect misstatements. Also, projections of any evaluation of effectiveness to future periods are subject to the risk that controls may become inadequate because of changes in conditions, or that the degree of compliance with the policies or procedures may deteriorate. Our management, including our President and Chief Executive Officer and Chief Financial Officer, assessed the effectiveness of our internal control over financial reporting as of December 31, 2022. In making this assessment, management used the criteria set forth by the Committee of Sponsoring Organizations of the Treadway Commission (COSO) in Internal Control—Integrated Framework (2013 ) . Based on that assessment, our management concluded that, as of December 31, 2022, our internal control over financial reporting was effective. Changes in Internal Control Over Financial Reporting No change in our internal control over financial reporting (as defined in Rules 13a-15(f) and 15d-15(f) under the Exchange Act) occurred during the three months ended December 31, 2022 that has materially affected, or is reasonably likely to materially affect, our internal control over financial reporting. Item 9B. Other Information None. Item 9C. Disclosure Regarding Foreign Jurisdictions That Prevent Inspections Not Applicable. ​ 118 Table of Contents PART III Item 10. Directors, Executive Officers and Corporate Governance Directors and Executive Officers The information required by this item will be set forth in our Proxy Statement for the 2023 Annual Meeting of Stockholders and is incorporated in this Annual Report on Form 10-K by reference. Delinquent Section 16(a) Reports The information required by this item will be set forth in our Proxy Statement for the 2023 Annual Meeting of Stockholders, if applicable, and is incorporated in this Annual Report on Form 10-K by reference. Code of Ethics We have adopted a code of business conduct and ethics that applies to our directors and officers (including our principal executive officer, principal financial officer, principal accounting officer or controller, or persons performing similar functions) as well as our other employees. A copy of our code of business conduct and ethics is available on our website. We intend to post on our website all disclosures that are required by applicable law, the rules of the Securities and Exchange Commission or the Nasdaq Global Market concerning any amendment to, or waiver of, our code of business conduct and ethics. Director Nominees The information required by this item will be set forth in our Proxy Statement for the 2023 Annual Meeting of Stockholders and is incorporated in this Annual Report on Form 10-K by reference. Audit Committee We have separately designated a standing Audit Committee established in accordance with Section 3(a)(58)(A) of the Securities Exchange Act of 1934, as amended, or the Exchange Act. Additional information regarding the Audit Committee that is required by this item will be set forth in our Proxy Statement for the 2023 Annual Meeting of Stockholders and is incorporated in this Annual Report on Form 10-K by reference. Audit Committee Financial Expert Our board of directors has determined that Merilee Raines qualifies as an “audit committee financial expert” as defined by Item 407(d)(5) of Regulation S-K of the Exchange Act and is “independent” under the rules of the Nasdaq Global Market. ​ Item 11. Executive Compensation The information required by this item will be set forth in our Proxy Statement for the 2023 Annual Meeting of Stockholders and is incorporated in this Annual Report on Form 10-K by reference. ​ Item 12. Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters The information required by this item will be set forth in our Proxy Statement for the 2023 Annual Meeting of Stockholders and is incorporated in this Annual Report on Form 10-K by reference. ​ 119 Table of Contents Item 13. Certain Relationships and Related Transactions, and Director Independence The information required by this item will be set forth in our Proxy Statement for the 2023 Annual Meeting of Stockholders and is incorporated in this Annual Report on Form 10-K by reference. ​ Item 14. Principal Accounting Fees and Services The information required by this item will be set forth in our Proxy Statement for the 2023 Annual Meeting of Stockholders and is incorporated in this Annual Report on Form 10-K by reference. ​ 120 Table of Contents ​ PART IV ​ Item 15. Exhibits, Financial Statement Schedules ​ The following financial statements are filed as part of this Annual Report on Form 10-K: ​ ​ ​ Page Report of Independent Registered Public Accounting Firm (PCAOB ID 238 ) ​ F-2 Consolidated Balance Sheets ​ F-4 Consolidated Statements of Operations and Comprehensive Loss ​ F-5 Consolidated Statements of Changes in Stockholders’ Equity (Deficit) ​ F-6 Consolidated Statements of Cash Flows ​ F-7 Notes to Consolidated Financial Statements ​ F-8 ​ No financial statement schedules have been filed as part of this Annual Report on Form 10-K because they are not applicable, not required or because the information is otherwise included in our consolidated financial statements or notes thereto. ​ The exhibits filed as part of this Annual Report on Form 10-K are set forth on the Exhibit Index immediately following Item 16. The Exhibit Index is incorporated herein by reference. ​ Item 16. Form 10-K Summary ​ None. ​ 121 Table of Contents EXHIBIT INDEX ​ ​ ​ ​ ​ Incorporated by Reference ​ ​ Exhibit Number Description of Exhibit Form File Number Date of Filing Exhibit Number Filed Herewith 3.1 ​ Restated Certificate of Incorporation of the Registrant ​ 8-K ​ 001-36554 ​ 7/30/2014 ​ 3.1 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 3.2 ​ Amended and Restated Bylaws of the Registrant ​ 8-K ​ 001-36554 ​ 7/30/2014 ​ 3.2 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 4.1 ​ Specimen Stock Certificate evidencing the shares of common stock ​ S-1/A ​ 333-196932 ​ 7/11/2014 ​ 4.1 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 4.2 ​ Registration Rights Agreement, dated as of March 1, 2019, by and among the Registrant and the Purchasers identified therein ​ 10-K ​ 001-36554 ​ 3/7/2019 ​ 4.2 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 4.3 ​ Description of Securities Registered under Section 12 of the Exchange Act ​ 10-K ​ 001-36554 ​ 2/28/2022 ​ 4.3 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 10.1+ ​ 2006 Stock Incentive Plan, as amended ​ S-1 ​ 333-196932 ​ 6/20/2014 ​ 10.1 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 10.2+ ​ Form of Stock Option Agreement under 2006 Stock Incentive Plan ​ S-1 ​ 333-196932 ​ 6/20/2014 ​ 10.2 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 10.3+ ​ Form of Restricted Stock Agreement under 2006 Stock Incentive Plan ​ S-1 ​ 333-196932 ​ 6/20/2014 ​ 10.3 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 10.4+ ​ 2014 Stock Incentive Plan ​ S-1/A ​ 333-196932 ​ 7/11/2014 ​ 10.4 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 10.5+ ​ Form of Incentive Stock Option Agreement under 2014 Stock Incentive Plan ​ S-1/A ​ 333-196932 ​ 7/11/2014 ​ 10.5 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 10.6+ ​ Form of Non-statutory Stock Option Agreement under 2014 Stock Incentive Plan ​ S-1/A ​ 333-196932 ​ 7/11/2014 ​ 10.6 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 10.7+ ​ Form of Restricted Stock Agreement under 2014 Stock Incentive Plan ​ S-1/A ​ 333-196932 ​ 7/11/2014 ​ 10.7 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 10.8+ ​ 2019 Inducement Stock Incentive Plan ​ 10-Q ​ 001-036554 ​ 11/12/2019 ​ 10.1 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 10.9+ ​ Amendment to 2019 Inducement Stock Incentive Plan ​ 10-K ​ 001-36554 ​ 3/11/2021 ​ 10.9 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 10.10+ ​ Form of Non-statutory Stock Option Agreement under 2019 Inducement Stock Incentive Plan ​ 10-Q ​ 001-036554 ​ 11/12/2019 ​ 10.2 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 122 Table of Contents ​ ​ ​ ​ Incorporated by Reference ​ ​ Exhibit Number Description of Exhibit Form File Number Date of Filing Exhibit Number Filed Herewith 10.11† ​ Amended and Restated License Agreement, dated January 27, 2012, between the Registrant and Incept LLC ​ S-1 ​ 333-196932 ​ 6/20/2014 ​ 10.8 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 10.12 ​ Lease Agreement dated September 2, 2009, by and between the Registrant and RAR2-Crosby Corporate Center QRS, Inc., as amended. ​ S-1 ​ 333-196932 ​ 6/20/2014 ​ 10.9 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 10.13+ ​ 2014 Employee Stock Purchase Plan ​ S-1/A ​ 333-196932 ​ 7/11/2014 ​ 10.10 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 10.14 ​ Form of Indemnification Agreement by and between the Registrant and each of its directors and executive officers ​ S-1 ​ 333-196932 ​ 6/20/2014 ​ 10.12 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 10.15 ​ Transition, Separation and Release of Claims Agreement by and between the Registrant and Dr. Amarpreet S. Sawhney dated as of May 29, 2019 ​ 8-K ​ 001-36554 ​ 5/30/2019 ​ 10.1 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 10.16 ​ Lease Agreement dated June 17, 2016 between the WS NF 15 Crosby Drive, LLC and the Registrant ​ 10-Q ​ 001-36554 ​ 8/9/2016 ​ 10.1 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 10.18 ​ Open Market Sale Agreement, dated as of August 9, 2021, by and between the Registrant and Jefferies LLC ​ 8-K ​ 001-36554 ​ 8/9/2021 ​ 1.1 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 10.19+ ​ Employment Agreement, by and between the Registrant and Philip Strassburger, dated August 28, 2020 ​ 10-K ​ 001-36554 ​ 3/11/2021 ​ 10.19 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 10.20 ​ Consulting Agreement by and between the Registrant and Dr. Amarpreet S. Sawhney, dated as of May 29, 2019 ​ 8-K ​ 001-36554 ​ 5/30/2019 ​ 10.2 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 10.21+ ​ Employment Agreement, by and between the Registrant and Antony C. Mattessich, dated as of June 20, 2017 ​ 8-K ​ 001-36554 ​ 6/22/2017 ​ 10.2 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 10.22+ ​ Non-Statutory Stock Option Agreement, by and between the Registrant and Antony C. Mattessich dated as of June 20, 2017 ​ 8-K ​ 001-36554 ​ 6/22/2017 ​ 10.3 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 123 Table of Contents ​ ​ ​ ​ Incorporated by Reference ​ ​ Exhibit Number Description of Exhibit Form File Number Date of Filing Exhibit Number Filed Herewith 10.23+ ​ Employment Agreement, by and between the Registrant and Donald Notman, dated as of September 25, 2017 ​ 8-K ​ 001-36554 ​ 9/25/2017 ​ 10.1 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 10.24 ​ Second Amendment to Lease, by and between the Registrant and CCC Investors LLC, dated October 10, 2017 ​ 8-K ​ 001-36554 ​ 10/16/2017 ​ 10.1 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 10.25+ ​ Employment Agreement, by and between the Registrant and Michael Goldstein, dated as of September 25, 2017 ​ 10-K ​ 001-36554 ​ 3/8/2018 ​ 10.30 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 10.26† ​ Second Amended and Restated License Agreement, dated September 13, 2018, by and between the Registrant and Incept LLC ​ 8-K ​ 001-36554 ​ 9/19/2018 ​ 10.1 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 10.27 ​ Third Amended and Restated Credit and Security Agreement dated December 21, 2018 by and among MidCap Financial Trust, as administrative agent, the Registrant, and the Lenders listed therein ​ 8-K ​ 001-36554 ​ 12/28/2018 ​ 10.1 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 10.28 ​ First Amendment to Third Amended and Restated Credit and Security Agreement, dated as of February 21, 2019, by and among the Registrant, MidCap Financial Trust, as administrative agent, and the Lenders listed therein ​ 8-K ​ 001-36554 ​ 2/22/2019 ​ 10.3 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 10.29 ​ Second Amendment to Third Amended and Restated Credit and Security Agreement, by and among the Registrant, MidCap Financial Trust, as administrative agent, and the Lenders listed therein ​ 10-Q ​ 001-36554 ​ 8/7/2019 ​ 10.5 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 10.30 ​ Subordination Agreement, dated as of February 21, 2019, by and among the Registrant, MidCap Financial Trust, as administrative agent, and the Lenders listed therein ​ 8-K ​ 001-36554 ​ 2/22/2019 ​ 10.4 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 10.31 ​ Note Purchase Agreement (including Form of Senior Subordinated Convertible Note), dated as of February 21, 2019, by and among the Registrant and the Purchasers listed therein ​ 8-K ​ 001-36554 ​ 2/22/2019 ​ 10.1 ​ ​ 124 Table of Contents ​ ​ ​ ​ Incorporated by Reference ​ ​ Exhibit Number Description of Exhibit Form File Number Date of Filing Exhibit Number Filed Herewith ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 10.32 ​ Sublease, dated as of April 4, 2019, by and among Ocular Therapeutix, Inc. and Holcim (US) Inc. ​ 10-Q ​ 001-36554 ​ 5/10/2019 ​ 10.4 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 10.35* ​ License Agreement, by and between the Registrant and AffaMed Therapeutics Limited, dated as of October 29, 2020 ​ 10-Q ​ 001-36554 ​ 11/5/2020 ​ 10.1 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 10.36* ​ Supplement to License Agreement, by and between the Registrant and AffaMed Therapeutics Limited, dated as of January 18, 2021 ​ 10-K ​ 001-36554 ​ 3/11/2021 ​ 10.36 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 10.37 ​ Fourth Amended and Restated Credit and Security Agreement dated June 4, 2021 by and among the Registrant, MidCap Financial Trust, as administrative agent, and the Lenders listen therein ​ 8-K ​ 001-36554 ​ ​ 6/4/2021 ​ ​ 10.1 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 10.38+ ​ 2021 Stock Incentive Plan, as amended ​ 10-Q ​ 001-36554 ​ 8/8/2022 ​ 10.1 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 10.39+ ​ Form of Option Grant Agreement under 2021 Stock Incentive Plan ​ 10-K ​ 001-36554 ​ 2/28/2022 ​ 10.1 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 10.40+ ​ Form of Restricted Stock Unit Agreement under 2021 Stock Incentive Plan ​ 10-K ​ 001-36554 ​ 2/28/2022 ​ 10.39 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 10.41 ​ Amendment No. 1 to License Agreement, by and between the Registrant and AffaMed Therapeutics (HK) Limited, dated as of October 28, 2021 ​ 10-K ​ 001-36554 ​ 2/28/2022 ​ 10.40 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 10.42 ​ Consulting Agreement by and between the Registrant and Dr. Michael Goldstein, dated as of June 7, 2022 ​ 10-Q ​ 001-36554 ​ 8/8/2022 ​ 10.2 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 10.43 ​ Consulting Agreement by and between the Registrant and Dr. Jeffrey Heier, dated as of October 17, 2022 ​ ​ ​ ​ ​ ​ ​ ​ ​ X ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 10.44 ​ Employment Agreement, by and between the Registrant and Rabia Ozden-Gurses, dated as of September 28, 2022 ​ ​ ​ ​ ​ ​ ​ ​ ​ X ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 125 Table of Contents ​ ​ ​ ​ Incorporated by Reference ​ ​ Exhibit Number Description of Exhibit Form File Number Date of Filing Exhibit Number Filed Herewith 10.45 ​ Employment Agreement, by and between the Registrant and Christopher White, dated as of October 13, 2022 ​ ​ ​ ​ ​ ​ ​ ​ ​ X ​ ​ ​ ​ ​ 21.1 ​ Subsidiaries of the Registrant ​ X ​ ​ ​ ​ ​ 23.1 ​ Consent of PricewaterhouseCoopers LLP ​ X ​ ​ ​ ​ ​ 31.1 ​ Certification of principal executive officer pursuant to Rule 13a-14(a)/15d-14(a) of the Securities Exchange Act of 1934, as amended ​ X ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 31.2 ​ Certification of principal financial officer pursuant to Rule 13a-14(a)/15d-14(a) of the Securities Exchange Act of 1934, as amended ​ X ​ ​ ​ ​ ​ 32.1 ​ Certification of principal executive officer pursuant to 18 U.S.C. §1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002 ​ X ​ ​ ​ ​ ​ 32.2 ​ Certification of principal financial officer pursuant to 18 U.S.C. §1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002 ​ X ​ ​ ​ ​ ​ 101.INS ​ Inline XBRL Instance Document (the instance document does not appear in the Interactive Data File because XBRL tags are embedded within the Inline XBRL document) ​ X ​ ​ ​ ​ ​ 101.SCH ​ Inline XBRL Taxonomy Extension Schema Document ​ X ​ ​ ​ ​ ​ 101.CAL ​ Inline XBRL Taxonomy Extension Calculation Linkbase Document ​ X ​ ​ ​ ​ ​ 101.LAB ​ Inline XBRL Taxonomy Extension Label Linkbase Database ​ X ​ ​ ​ ​ ​ 101.PRE ​ Inline XBRL Taxonomy Extension Presentation Linkbase Document ​ X ​ ​ ​ ​ ​ 101.DEF ​ Inline XBRL Taxonomy Extension Definition Linkbase Document ​ X ​ ​ ​ ​ ​ 104 ​ The cover page from this Annual Report on Form 10-K, formatted in Inline XBRL and contained in Exhibit 101 ​ X † Confidential treatment has been granted as to certain portions, which portions have been omitted and separately filed with the Securities and Exchange Commission. + Management contract or compensatory plan or arrangement filed in response to Item 15(a)(3) of the Instructions to the Annual Report on Form 10-K. ​ * Certain portions of this exhibit have been omitted pursuant to Item 601(b)(10)(iv) of Regulation S-K. ​ ​ 126 Table of Contents SIGNATURES ​ Pursuant to the requirements of Section 13 or 15(d) of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized. ​ Date: March 6, 2023 ​ ​ ​ ​ ​ OCULAR THERAPEUTIX, INC. ​ ​ ​ ​ By: /s/ Donald Notman ​ ​ Donald Notman ​ ​ Chief Financial Officer ​ ​ (Principal Financial and Accounting Officer) ​ Pursuant to the requirements of the Securities Exchange Act of 1934, this report has been signed by the following persons on behalf of the registrant in the capacities and on the dates indicated. ​ Signature Title Date ​ ​ ​ ​ ​ /s/ Antony Mattessich ​ President and Chief Executive Officer ​ ​ Antony Mattessich ​ (Principal Executive Officer) ​ March 6, 2023 ​ ​ ​ ​ ​ /s/ Donald Notman ​ Chief Financial Officer ​ March 6, 2023 Donald Notman ​ (Principal Financial and Accounting Officer) ​ ​ ​ ​ ​ ​ ​ /s/ Charles Warden ​ Chairman of the Board ​ March 6, 2023 Charles Warden ​ ​ ​ ​ ​ ​ ​ ​ ​ /s/ Jeffrey S. Heier, M.D. ​ Director ​ March 6, 2023 Jeffrey S. Heier, M.D. ​ ​ ​ ​ ​ ​ ​ ​ ​ /s/ Seung Suh Hong, PH.D. ​ Director ​ March 6, 2023 Seung Suh Hong, PH.D. ​ ​ ​ ​ ​ ​ ​ ​ ​ /s/ Richard L. Lindstrom, M.D. ​ Director ​ March 6, 2023 Richard L. Lindstrom, M.D. ​ ​ ​ ​ ​ ​ ​ ​ ​ /s/ Merilee Raines ​ Director ​ March 6, 2023 Merilee Raines ​ ​ ​ ​ ​ ​ ​ ​ ​ /s/ Leslie Williams ​ Director ​ March 6, 2023 Leslie Williams ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Table of Contents OCULAR THERAPEUTIX, INC. ​ Index to CONSOLIDATED FINANCIAL STATEMENTS ​ ​ ​ Page Report of Independent Registered Public Accounting Firm (PCAOB ID 238) ​ F-2 Consolidated Balance Sheets ​ F-4 Consolidated Statements of Operations and Comprehensive Loss ​ F-5 Consolidated Statements of Changes in Stockholders’ Equity (Deficit) ​ F-6 Consolidated Statements of Cash Flows ​ F-7 Notes to Consolidated Financial Statements ​ F-8 ​ ​ ​ F-1 Table of Contents Report of Independent Registered Public Accounting Firm ​ To the Board of Directors and Stockholders of Ocular Therapeutix, Inc. Opinions on the Financial Statements We have audited the accompanying consolidated balance sheets of Ocular Therapeutix, Inc. and its subsidiaries (the “Company”) as of December 31, 2022 and 2021, and the related consolidated statements of operations and comprehensive loss, of stockholders’ equity (deficit) and of cash flows for each of the three years in the period ended December 31, 2022, including the related notes (collectively referred to as the “consolidated financial statements”). In our opinion, the consolidated financial statements present fairly, in all material respects, the financial position of the Company as of December 31, 2022 and 2021, and the results of its operations and its cash flows for each of the three years in the period ended December 31, 2022 in conformity with accounting principles generally accepted in the United States of America. Emphasis of Matter As discussed in Note 1 to the consolidated financial statements, the Company will require additional financing to fund future operations. Management’s evaluation of the events and conditions and management’s plans to mitigate these matters are also described in Note 1. Basis for Opinion These consolidated financial statements are the responsibility of the Company’s management. Our responsibility is to express an opinion on the Company’s consolidated financial statements based on our audits. We are a public accounting firm registered with the Public Company Accounting Oversight Board (United States) (PCAOB) and are required to be independent with respect to the Company in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB. We conducted our audits of these consolidated financial statements in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audits to obtain reasonable assurance about whether the consolidated financial statements are free of material misstatement, whether due to error or fraud. The Company is not required to have, nor were we engaged to perform, an audit of its internal control over financial reporting. As part of our audits we are required to obtain an understanding of internal control over financial reporting but not for the purpose of expressing an opinion on the effectiveness of the Company's internal control over financial reporting. Accordingly, we express no such opinion. Our audits included performing procedures to assess the risks of material misstatement of the consolidated financial statements, whether due to error or fraud, and performing procedures that respond to those risks. Such procedures included examining, on a test basis, evidence regarding the amounts and disclosures in the consolidated financial statements. Our audits also included evaluating the accounting principles used and significant estimates made by management, as well as evaluating the overall presentation of the consolidated financial statements. We believe that our audits provide a reasonable basis for our opinion. Critical Audit Matters The critical audit matter communicated below is a matter arising from the current period audit of the consolidated financial statements that was communicated or required to be communicated to the audit committee and that (i) relates to accounts or disclosures that are material to the consolidated financial statements and (ii) involved our especially challenging, subjective, or complex judgments. The communication of critical audit matters does not alter in any way our opinion on the consolidated financial statements, taken as a whole, and we are not, by communicating the critical audit matter below, providing a separate opinion on the critical audit matter or on the accounts or disclosures to which it relates. Valuation of the Derivative Liability As described in Notes 2, 10 and 11 to the consolidated financial statements, the Company’s derivative liability balance was $6.4 million as of December 31, 2022 and the change in fair value recorded in other income (expense), net was $13.8 million for the year ended December 31, 2022. The derivative liability was recorded at fair value upon the F-2 Table of Contents issuance of the 2026 convertible notes and is subsequently remeasured to fair value at each reporting period. The derivative liability was initially valued and remeasured using a “with-and-without” method. The “with-and-without” methodology involves valuing the whole instrument on an as-is basis and then valuing the instrument without the embedded conversion option. The difference between the entire instrument with the embedded conversion option compared to the instrument without the embedded conversion option is the fair value of the derivative, recorded as the derivative liability. The fair value of the 2026 convertible notes with and without the conversion option is estimated using a binomial lattice approach. The main inputs to valuing the 2026 convertible notes with the conversion option as of December 31, 2022 include the Company’s stock price on the valuation date, the expected annual volatility of the Company’s stock and the bond yield. The significant assumption used in determining the bond yield is the market yield movements of a comparable instrument issued as of the valuation date, which is assessed and updated each period. The principal considerations for our determination that performing procedures relating to the valuation of the derivative liability is a critical audit matter are the significant judgment by management to determine the fair value of the derivative liability using a binomial lattice approach; this in turn led to a high degree of auditor judgment, subjectivity, and effort in performing procedures and in evaluating the audit evidence obtained related to the valuation of the derivative liability and management’s significant assumption related to market yield movements used in determining the bond yield input. In addition, the audit effort involved the use of professionals with specialized skill and knowledge. Addressing the matter involved performing procedures and evaluating audit evidence in connection with forming our overall opinion on the consolidated financial statements. These procedures included, among others (i) the involvement of professionals with specialized skill and knowledge to assist in developing an independent range of fair values for the derivative liability and (ii) comparing the independent estimate to management’s fair value estimate to evaluate the reasonableness of management’s estimate. Developing the independent estimate involved testing the completeness and accuracy of the inputs provided by management and evaluating the reasonableness of management’s significant assumption related to market yield movements used in determining the bond yield by considering observable data. /s/ PricewaterhouseCoopers LLP Boston, Massachusetts March 6, 2023 We have served as the Company’s auditor since 2008. ​ F-3 Table of Contents OCULAR THERAPEUTIX, INC. ​ CONSOLIDATED BALANCE SHEETS ​ (In thousands, except share and per share data) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ December 31, ​ 2022 2021 Assets ​ ​ Current assets: ​ ​ ​ Cash and cash equivalents ​ $ 102,300 ​ $ 164,164 Accounts receivable, net ​ 21,325 ​ 21,135 Inventory ​ 1,974 ​ 1,250 Prepaid expenses and other current assets ​ 4,028 ​ 4,751 Total current assets ​ 129,627 ​ 191,300 Property and equipment, net ​ 9,856 ​ 6,956 Restricted cash ​ 1,764 ​ 1,764 Operating lease assets ​ ​ 8,042 ​ ​ 4,867 Total assets ​ $ 149,289 ​ $ 204,887 Liabilities and Stockholders’ Equity ​ ​ ​ Current liabilities: ​ ​ ​ Accounts payable ​ $ 5,123 ​ $ 4,592 Accrued expenses and other current liabilities ​ 24,097 ​ 20,121 Deferred revenue ​ 576 ​ — Operating lease liabilities ​ ​ 1,599 ​ ​ 1,624 Total current liabilities ​ 31,395 ​ 26,337 Other liabilities: ​ ​ ​ ​ Operating lease liabilities, net of current portion ​ ​ 8,678 ​ ​ 5,924 Derivative liability ​ ​ 6,351 ​ ​ 20,192 Deferred revenue, net of current portion ​ ​ 13,387 ​ ​ 13,000 Notes payable, net of discount ​ 25,257 ​ 25,000 Other Non-Current Liabilities ​ ​ 93 ​ ​ — 2026 convertible notes, net ​ 28,749 ​ 26,435 Total liabilities ​ 113,910 ​ 116,888 Commitments and contingencies (Note 17) ​ ​ ​ ​ Stockholders’ equity: ​ ​ ​ Preferred stock, $ 0.0001 par value; 5,000,000 shares authorized and no shares issued or outstanding at December 31, 2022 and December 31, 2021, respectively ​ — ​ — Common stock, $ 0.0001 par value; 200,000,000 shares authorized and 77,201,819 and 76,731,940 shares issued and outstanding at December 31, 2022 and December 31, 2021, respectively ​ 8 ​ 8 Additional paid-in capital ​ 652,213 ​ 633,795 Accumulated deficit ​ ( 616,842 ) ​ ( 545,804 ) Total stockholders’ equity ​ 35,379 ​ 87,999 Total liabilities and stockholders’ equity ​ $ 149,289 ​ $ 204,887 ​ The accompanying notes are an integral part of these consolidated financial statements. ​ F-4 Table of Contents ​ OCULAR THERAPEUTIX, INC. ​ CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS ​ (In thousands, except share and per share data) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 2022 2021 2020 Revenue: ​ ​ ​ Product revenue, net ​ $ 50,457 ​ $ 43,522 ​ $ 17,403 ​ Collaboration revenue ​ 1,037 ​ — ​ — ​ Total revenue, net ​ 51,494 ​ ​ 43,522 ​ ​ 17,403 ​ Costs and operating expenses: ​ ​ ​ ​ ​ ​ ​ Cost of product revenue ​ 4,540 ​ 4,406 ​ 2,083 ​ Research and development ​ 53,462 ​ 50,083 ​ 28,694 ​ Selling and marketing ​ 39,922 ​ 35,190 ​ 26,614 ​ General and administrative ​ 32,224 ​ 31,880 ​ 22,859 ​ Total costs and operating expenses ​ 130,148 ​ ​ 121,559 ​ ​ 80,250 ​ Loss from operations ​ ( 78,654 ) ​ ​ ( 78,037 ) ​ ​ ( 62,847 ) ​ Other income (expense): ​ ​ ​ ​ ​ ​ ​ Interest income ​ 798 ​ 33 ​ 168 ​ Interest expense ​ ( 7,022 ) ​ ( 6,671 ) ​ ( 6,768 ) ​ Change in fair value of derivative liability ​ ​ 13,841 ​ ​ 78,121 ​ ​ ( 86,189 ) ​ Other income (expense), net ​ ( 1 ) ​ 1 ​ — ​ Total other (expense) income, net ​ 7,616 ​ ​ 71,484 ​ ​ ( 92,789 ) ​ Net loss ​ $ ( 71,038 ) ​ $ ( 6,553 ) ​ $ ( 155,636 ) ​ Net loss per share, basic ​ $ ( 0.92 ) ​ $ ( 0.09 ) ​ $ ( 2.56 ) ​ Weighted average common shares outstanding, basic ​ 76,875,035 ​ 76,392,870 ​ 60,752,225 ​ Net loss per share, diluted ​ $ ( 0.97 ) ​ $ ( 0.98 ) ​ $ ( 2.56 ) ​ Weighted average common shares outstanding, diluted ​ 82,644,267 ​ ​ 82,162,102 ​ ​ 60,752,225 ​ ​ The accompanying notes are an integral part of these consolidated financial statements. ​ F-5 Table of Contents OCULAR THERAPEUTIX, INC. ​ CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS’ EQUITY (DEFICIT) ​ (In thousands, except share data) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total ​ ​ ​ ​ ​ ​ ​ ​ Additional ​ ​ ​ ​ Stockholders’ ​ ​ ​ Common Stock ​ Paid-in ​ Accumulated ​ Equity ​ Shares Par Value Capital Deficit (Deficit) Balances at December 31, 2019 50,333,559 ​ ​ 5 ​ ​ 379,980 ​ ​ ( 383,615 ) ​ ​ ( 3,630 ) Issuance of common stock upon exercise of stock options 567,776 ​ 1 ​ 2,585 ​ — ​ 2,586 Issuance of common stock in connection with employee stock purchase plan 161,175 ​ — ​ 747 ​ — ​ 747 Issuance of common stock upon public offering, net of issuance costs 24,934,222 ​ 2 ​ 224,495 ​ — ​ 224,497 Stock-based compensation expense — ​ — ​ 7,531 ​ — ​ 7,531 Net loss — ​ — ​ — ​ ( 155,636 ) ​ ( 155,636 ) Balances at December 31, 2020 75,996,732 ​ ​ 8 ​ ​ 615,338 ​ ​ ( 539,251 ) ​ ​ 76,095 Issuance of common stock upon exercise of stock options 598,923 ​ — ​ ​ 2,586 ​ — ​ 2,586 Issuance of common stock in connection with employee stock purchase plan 124,548 ​ — ​ ​ 985 ​ — ​ 985 Issuance of common stock upon cashless exercise of warrant 11,737 ​ — ​ ​ — ​ — ​ — Common stock issuance costs — ​ ​ — ​ ​ ( 91 ) ​ ​ — ​ ​ ( 91 ) Stock-based compensation expense — ​ — ​ 14,977 ​ — ​ 14,977 Net loss — ​ — ​ — ​ ( 6,553 ) ​ ( 6,553 ) Balances at December 31, 2021 76,731,940 ​ ​ 8 ​ ​ 633,795 ​ ​ ( 545,804 ) ​ ​ 87,999 Issuance of common stock upon exercise of stock options 137,502 ​ ​ — ​ ​ 514 ​ ​ — ​ ​ 514 Issuance of common stock in connection with employee stock purchase plan 332,377 ​ ​ — ​ ​ 940 ​ ​ — ​ ​ 940 Stock-based compensation expense — ​ ​ — ​ ​ 16,964 ​ ​ — ​ ​ 16,964 Net loss — ​ ​ — ​ ​ — ​ ​ ( 71,038 ) ​ ​ ( 71,038 ) Balances at December 31, 2022 77,201,819 ​ $ 8 ​ $ 652,213 ​ $ ( 616,842 ) ​ $ 35,379 ​ The accompanying notes are an integral part of these consolidated financial statements. ​ F-6 Table of Contents ​ OCULAR THERAPEUTIX, INC. ​ CONSOLIDATED STATEMENTS OF CASH FLOWS ​ (In thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 2022 2021 2020 Cash flows from operating activities: ​ ​ ​ Net loss ​ $ ( 71,038 ) ​ $ ( 6,553 ) ​ $ ( 155,636 ) ​ Adjustments to reconcile net loss to net cash used in operating activities ​ ​ ​ ​ ​ ​ ​ Stock-based compensation expense ​ 16,964 ​ 14,977 ​ 7,531 ​ Non-cash interest expense ​ 4,853 ​ 4,628 ​ 4,415 ​ Change in fair value of derivative liability ​ ​ ( 13,841 ) ​ ​ ( 78,121 ) ​ ​ 86,189 ​ Depreciation and amortization expense ​ 2,109 ​ 2,421 ​ 2,773 ​ Gain (loss) on disposal of property and equipment ​ 1 ​ ( 1 ) ​ — ​ Changes in operating assets and liabilities: ​ ​ ​ ​ ​ ​ ​ Accounts receivable ​ ( 190 ) ​ ( 8,883 ) ​ ( 9,704 ) ​ Prepaid expenses and other current assets ​ 723 ​ ( 101 ) ​ ( 2,419 ) ​ Inventory ​ ( 724 ) ​ ( 49 ) ​ ( 247 ) ​ Operating lease assets ​ ​ ( 3,175 ) ​ ​ 977 ​ ​ 811 ​ Accounts payable ​ ( 621 ) ​ 1,796 ​ ( 452 ) ​ Accrued expenses ​ 1,644 ​ 3,717 ​ 2,311 ​ Deferred revenue ​ ​ 963 ​ ​ 1,000 ​ ​ 12,000 ​ Operating lease liabilities ​ 2,729 ​ ( 1,358 ) ​ ( 1,125 ) ​ Net cash used in operating activities ​ ( 59,603 ) ​ ( 65,550 ) ​ ( 53,554 ) ​ Cash flows from investing activities: ​ ​ ​ ​ Purchases of property and equipment ​ ( 3,715 ) ​ ( 1,194 ) ​ ( 841 ) ​ Net cash used in investing activities ​ ( 3,715 ) ​ ( 1,194 ) ​ ( 841 ) ​ Cash flows from financing activities: ​ ​ ​ ​ Proceeds from issuance of notes payable, net ​ — ​ 3,722 ​ — ​ Proceeds from exercise of stock options ​ 514 ​ 2,586 ​ 2,585 ​ Proceeds from issuance of common stock pursuant to employee stock purchase plan ​ 940 ​ 985 ​ 747 ​ Proceeds from the Paycheck Protection Program Loan ​ ​ — ​ ​ — ​ ​ 3,201 ​ Repayment of the Paycheck Protection Program Loan ​ ​ — ​ ​ — ​ ​ ( 3,201 ) ​ Proceeds from issuance of common stock upon public offering, net of issuance costs ​ — ​ — ​ 224,682 ​ Issuance costs from the issuance of common stock upon public offering ​ — ​ ( 275 ) ​ — ​ Repayment of notes payable ​ — ​ ( 4,167 ) ​ — ​ Net cash provided by financing activities ​ 1,454 ​ ​ 2,851 ​ 228,014 ​ Net decrease in cash, cash equivalents and restricted cash ​ ( 61,864 ) ​ ( 63,893 ) ​ 173,620 ​ Cash, cash equivalents and restricted cash at beginning of period ​ 165,928 ​ 229,821 ​ 56,201 ​ Cash, cash equivalents and restricted cash at end of period ​ $ 104,064 ​ $ 165,928 ​ $ 229,821 ​ Supplemental disclosure of cash flow information: ​ ​ ​ ​ Cash paid for interest ​ $ 2,147 ​ $ 1,932 ​ $ 2,354 ​ Supplemental disclosure of non-cash investing and financing activities: ​ ​ ​ ​ ​ ​ ​ Additions to property and equipment included in accounts payable and accrued expenses ​ $ 1,384 ​ $ 181 ​ $ 91 ​ Public offering costs included in accounts payable and accrued expenses at balance sheet dates ​ $ — ​ $ — ​ $ 184 ​ ​ The accompanying notes are an integral part of these consolidated financial statements. ​ ​ F-7 Table of Contents OCULAR THERAPEUTIX, INC. ​ NOTES TO CONSOLIDATED FINANCIAL STATEMENTS ​ (Amounts in thousands, except share and per share data) ​ 1. Nature of the Business and Basis of Presentation ​ Ocular Therapeutix, Inc. (the “Company”) was incorporated on September 12, 2006 under the laws of the State of Delaware. The Company is a biopharmaceutical company focused on the formulation, development and commercialization of innovative therapies for diseases and conditions of the eye using its proprietary bioresorbable hydrogel-based formulation technology. The Company’s mission is to build an ophthalmology-focused biopharmaceutical company that capitalizes on the gaps that the Company believes increasingly exist in the ophthalmology sector between single product companies and large, multi-product pharmaceutical companies. ​ The Company is subject to risks common to companies in the biotechnology industry including, but not limited to, new technological innovations, protection of proprietary technology, dependence on key personnel, compliance with government regulations, regulatory approval and compliance, reimbursement, uncertainty of market acceptance of products and the need to obtain additional financing. Recently approved products will require significant sales, marketing and distribution support up to and including upon their launch. Product candidates currently under development will require significant additional research and development efforts, including extensive preclinical and clinical testing and regulatory approval, prior to commercialization. ​ The Company is currently commercializing DEXTENZA® (dexamethasone insert) 0.4mg, an intracanalicular insert for the treatment of post-surgical ocular inflammation and pain and for the treatment of ocular itching associated with allergic conjunctivitis, in the United States. The Company suspended the production of ReSure® Sealant, an ophthalmic device designed to prevent wound leaks in corneal incisions following cataract surgery, as of the fourth quarter of 2021 in order to focus our manufacturing resources on DEXTENZA. Currently, ReSure Sealant is not commercially available in the United States, and we have received only limited revenues from ReSure Sealant to date. The Company’s most advanced product candidates are in either Phase 1 or Phase 2 of clinical stage development. There can be no assurance that the Company’s research and development will be successfully completed, that adequate protection for the Company’s intellectual property will be obtained, that any products developed will obtain necessary government regulatory approval and adequate reimbursement or that any approved products will be commercially viable. Even if the Company’s product development efforts are successful, it is uncertain when, if ever, the Company will generate significant revenue from product sales. The Company operates in an environment of rapidly changing technology and substantial competition from pharmaceutical and biotechnology companies. In addition, the Company is dependent upon the services of its employees and consultants. The Company may not be able to generate significant revenue from sales of any product for several years, if at all. Accordingly, the Company will need to obtain additional capital to finance its operations. ​ The Company has incurred losses and negative cash flows from operations since its inception, and the Company expects to continue to generate operating losses and negative cash flows from operations in the foreseeable future. As of December 31, 2022, the Company had an accumulated deficit of $ 616,842 . Based on its current operating plan which includes estimates of anticipated cash inflows from product sales and cash outflows from operating expenses, the Company believes that its existing cash and cash equivalents of $ 102,300 as of December 31, 2022 will enable it to fund its planned operating expenses, debt service obligations and capital expenditures at least through the next 12 months from the issuance date of these consolidated financial statements. The future viability of the Company beyond that point is dependent on its ability to generate cash flows from the sale of DEXTENZA and raise additional capital to finance its operations. The Company will need to finance its operations through public or private securities offerings, debt financings, collaborations, strategic alliances, licensing agreements, royalty agreements, or marketing and distribution agreements. Although the Company has been successful in raising capital in the past, there is no assurance that it will be successful in obtaining such additional financing on terms acceptable to the Company, if at all. If the Company is unable to obtain funding, the Company could be forced to delay, reduce or eliminate some or all of its research and development programs for product candidates, product portfolio expansion or commercialization efforts, which could adversely affect its business prospects, or the Company may be unable to continue operations. ​ ​ F-8 Table of Contents 2. Summary of Significant Accounting Policies ​ Basis of Presentation and Principles of Consolidation ​ The accompanying consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (“GAAP”). The accompanying consolidated financial statements reflect the operations of the Company and its wholly-owned subsidiaries. All intercompany accounts and transactions have been eliminated. ​ Use of Estimates ​ The preparation of consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the consolidated financial statements, and the reported amounts of revenues and expenses during the reporting periods. Significant estimates and assumptions reflected in these consolidated financial statements include, but are not limited to, the measurement and recognition of reserves for variable consideration related to product sales, revenue recognition related to a collaboration agreement that contains multiple promises, the fair value of derivatives, stock-based compensation, and realizability of net deferred tax assets. Estimates are periodically reviewed in light of changes in circumstances, facts and experience. Actual results could differ from the Company’s estimates. ​ Cash Equivalents ​ The Company considers all short-term, highly liquid investments with original maturities of ninety days or less at date of purchase to be cash equivalents. Cash equivalents, which primarily consist of investments in money market funds, are stated at fair value. ​ Revenue Recognition ​ The Company recognizes revenue in accordance with Accounting Standards Codification (“ASC”) Topic 606 – Revenue from Contracts with Customers (“ASC 606”). Under ASC 606, an entity recognizes revenue when a customer obtains control of promised goods or services, in an amount that reflects the consideration which the entity expects to be entitled to in exchange for those goods or services. To determine revenue recognition for arrangements that an entity determines are within the scope of ASC 606, the entity performs the following five steps: (i) identify the contract(s) with a customer, (ii) identify the performance obligations in the contract, (iii) determine the transaction price, (iv) allocate the transaction price to the performance obligations in the contract, and (v) recognize revenue when (or as) the entity satisfies a performance obligation. At contract inception, the Company assesses the goods or services promised within each contract, determines those that are performance obligations, and assesses whether each promised good or service is distinct. The Company then recognizes as revenue the amount of the transaction price that is allocated to the respective performance obligation when (or as) the performance obligation is satisfied. ​ Product Revenue ​ The Company sells DEXTENZA in the United States primarily to a limited number of specialty distributors (“SDs”) under individually negotiated distribution agreements. These customers then subsequently resell DEXTENZA to physicians, clinics and certain medical centers or hospitals. The Company also sells DEXTENZA directly to a small population of ambulatory surgery centers, or ASCs, based on individually negotiated direct distribution agreements (the “Direct Customers”). In addition, the Company enters into arrangements with health care providers and payors that provide for government mandated or privately negotiated rebates and chargebacks with respect to the purchase of DEXTENZA. ​ The Company recognizes revenue on product sales when the customer obtains control of the Company's product, which occurs at a point in time (upon delivery to the customer). Product revenues are recorded net of applicable reserves for variable consideration, including discounts and allowances. ​ F-9 Table of Contents Transaction Price, including Variable Consideration — Revenues from product sales are recorded net of off-invoice discounts and reserves which are established for our estimate of variable consideration. Components of variable consideration include trade discounts and allowances, product returns, government chargebacks, discounts and rebates, and other incentives, such as voluntary patient assistance, and other fee-for-service amounts that are detailed within contracts between the Company and its customers. These reserves, as detailed below, are based on the amounts earned, or to be claimed on the related sales, and are classified as reductions of accounts receivable or a current liability. These estimates take into consideration a range of possible outcomes which are probability-weighted in accordance with the expected value method in ASC 606 for relevant factors such as current contractual and statutory requirements, specific known market events and trends, industry data, and forecasted customer buying and payment patterns. Overall, these reserves reflect the Company’s best estimates of the amount of consideration to which it is entitled based on the terms of the respective underlying contracts. ​ The amount of variable consideration which is included in the transaction price may be constrained, and is included in the net sales price, only to the extent that it is probable that a significant reversal in the amount of the cumulative revenue recognized under the contract will not occur in a future period. Actual amounts of consideration ultimately received may differ from the Company’s estimates. If actual results in the future vary from the Company’s original estimates, the Company will adjust these estimates, which would affect net product revenue and earnings in the period such variances become known. ​ Trade Discounts and Allowances —The Company compensates (through trade discounts and allowances) its customers for sales order management, data, and distribution services. However, the Company has determined such services received to date are not distinct from the Company’s sale of products to the customer and, therefore, these payments have been recorded as a reduction of revenue within the statement of operations and comprehensive loss, as well as a reduction to accounts receivables, net on the consolidated balance sheets. ​ Product Returns — Consistent with industry practice, the Company generally offers customers a limited right of return for product that has been purchased from the Company based on the products expiration date. The Company estimates the amount of its product sales that may be returned by its customers and records this estimate as a reduction of revenue in the period the related product revenue is recognized, as well as within accrued expenses and other current liabilities, in the accompanying consolidated balance sheets. The Company currently estimates product return reserves using available industry data and its own sales information, including its visibility into the inventory remaining in the distribution channel. ​ Government Chargebacks — Chargebacks for fees and discounts to qualified government healthcare providers represent the estimated obligations resulting from contractual commitments to sell products to qualified U.S. Department of Veterans Affairs hospitals and entities that are subject to the U.S. federal government 340B Drug Discount Program entities at prices lower than the list prices charged to SDs and Direct Customers. Chargeback amounts are generally determined at the time of resale to the qualified government healthcare provider by SDs and Direct Customers, and the Company generally issues credits for such amounts within a few weeks of the Customer’s notification to the Company of the resale. Allowance for chargebacks also consist of credits that the Company expects to issue for units that remain in the distribution channel inventories at each reporting period-end that the Company expects will be sold to qualified healthcare providers, and chargebacks that customers have claimed, but for which the Company has not yet issued a credit. These allowances are established in the same period that the related revenue is recognized, resulting in a reduction of product revenue and accounts receivables, net. Government Rebates — The Company is subject to discount obligations under state Medicaid programs and Medicare. These reserves are recorded in the same period the related revenue is recognized, resulting in a reduction of product revenue and the establishment of a current liability which is included in accrued expenses and other current liabilities on the consolidated balance sheets. For Medicare, the Company also estimates the number of patients in the prescription drug coverage gap for whom the Company will owe an additional liability under the Medicare Part D program. For Medicaid programs, the Company estimates the portion of sales attributed to Medicaid patients and records a liability for the rebates to be paid to the respective state Medicaid programs. The Company’s liability for these rebates consists of invoices received for claims from prior quarters that have not been paid or for which an invoice has not yet been received, estimates of claims for the current quarter, and estimated future claims that will be made for product that has been recognized as revenue, but which remains in the distribution channel inventories at the end of each reporting period. ​ F-10 Table of Contents Purchaser/Provider Discounts and Rebates — The Company offers rebate payments for which ASCs, hospital out-patient departments and other prescribers qualify by meeting quarterly purchase volumes of DEXTENZA under the Company’s volume-based rebate program. The Company calculates rebate payment amounts due under this program quarterly, based on actual qualifying purchases and applies a contractual discount rate. In the third quarter of 2022, the Company implemented a separate off-invoice discount (“OID”) rebate program whereby end- users receive the discounted price immediately upon purchase, rather than having to wait until the end of the quarter for a rebate payment. The OID amounts are generally determined at the time of resale by SDs or direct sales to ASCs by the Company. The Company generally issues credits for such amounts within a few weeks of the SD’s notification to the Company of the resale. The Company includes the OID on the invoice when it sells to an ASC directly. The calculation of the accrual for all rebates is based on an estimate of claims that the Company expects to receive associated with product that has been recognized as revenue but also remains in the distribution channel inventories at the end of each reporting period. The adjustments are recorded in the same period the related revenue is recognized, resulting in a reduction of product revenue and the establishment of a current liability which is included as an accrued expenses and other current liabilities for volume-based rebates and as a reduction of accounts receivable for OID rebates. ​ Other Incentives — Other incentives which the Company offers include voluntary patient assistance programs, such as the co-pay assistance program, which are intended to provide financial assistance to qualified commercially-insured patients with prescription drug co-payments required by payors. The calculation of the accrual for co-pay assistance is based on an estimate of claims and the cost per claim that the Company expects to receive associated with product that has been recognized as revenue, but remains in the distribution channel inventories at the end of each reporting period. The adjustments are recorded in the same period the related revenue is recognized, resulting in a reduction of product revenue and the establishment of a current liability which is included as an accrued expenses and other current liabilities on the consolidated balance sheets. ​ Collaboration Revenue ​ The Company evaluates contracts that contain multiple promises to determine which promises are distinct. Promises are considered to be distinct and therefore, accounted for as separate performance obligations, provided that: (i) the customer can benefit from the good or service either on its own or together with other resources that are readily available to the customer and (ii) the promise to transfer the good or service to the customer is separately identifiable from other promises in the contract. In assessing whether a promise is distinct, the Company considers factors such as whether: (i) the Company provides a significant service of integrating goods and/or services with other goods and/or services promised in the contract; (ii) one or more of the goods and/or services significantly modifies or customizes, or are significantly modified or customized by one or more of the other goods and/or services promised in the contract; and (iii) the goods and/or services are highly interdependent or highly interrelated. Individual goods or services (or bundles of goods and/or services) that meet both criteria for being distinct are accounted for as separate performance obligations. Promises that are not distinct at contract inception are combined and accounted for as a single performance obligation. Options to acquire additional goods and/or services are evaluated to determine if such option provides a material right to the customer that it would not have received without entering into the contract. If so, the option is accounted for as a separate performance obligation. If not, the option is considered a marketing offer which would be accounted for as a separate contract upon the customer’s election. ​ The Company considers the existence of any significant financing component within its arrangements based on whether a substantive business purposes exist to support the payment structure other than to provide a significant benefit of financing. The Company measures the transaction price based on the amount of consideration to which the Company expects to be entitled in exchange for transferring the promised goods and/or services to the customer. The Company utilizes either the expected value method or the most likely amount method to estimate the amount of variable consideration, depending on which method is expected to better predict the amount of consideration to which the Company will be entitled. Amounts of variable consideration are included in the transaction price to the extent that it is probable that a significant reversal in the amount of cumulative revenue recognized will not occur when the uncertainty associated with the variable consideration is subsequently resolved. With respect to arrangements that include payments for a development or regulatory milestone payment, the Company evaluates whether the associated event is considered likely of achievement and estimates the amount to be included in the transaction price using the most likely amount method. Milestone payments that are not within the Company’s control or the licensee, such as those dependent upon receipt of regulatory approval, are not considered to be likely of achievement until the triggering event occurs. At the end of each reporting period, the Company re-evaluates the probability of achievement of each milestone and any related constraint, and if necessary, adjust its estimate of the overall transaction price. Any such adjustments are recorded on a F-11 Table of Contents cumulative catch-up basis, which would affect revenue and net loss in the period of adjustment. For arrangements that include sales-based royalties, including milestone payments based upon the achievement of a certain level of product sales, wherein the license is deemed to be the sole or predominant item to which the payments relate, the Company recognizes revenue upon the later of: (i) when the related sales occur or (ii) when the performance obligation to which some or all of the payment has been allocated has been satisfied (or partially satisfied). Consideration that would be received for optional goods and/or services is excluded from the transaction price at contract inception. Accounts Receivable ​ Accounts receivable arise from product sales and are recognized at the amounts invoiced to customers, net of applicable reserves for variable consideration. The Company analyzes the actual payment history of its customers, the aging of receivables, current customer-specific developments and economic trends to estimate the reserve for current expected credit losses. ​ Inventory ​ The Company values its inventories at the lower of cost or estimated net realizable value. Costs, which include amounts related to direct labor, materials and manufacturing overhead, are determined using standard costs, which approximate average cost. The Company performs an assessment of the recoverability of capitalized inventory during each reporting period, and it writes down any excess and obsolete inventories to their estimated realizable value in the period in which the impairment is first identified. Such impairment charges, should they occur, are recorded within cost of product revenue. The Company capitalizes inventory costs associated with the Company’s products after regulatory approval when, based on management’s judgment, future commercialization is considered probable and the future economic benefit is expected to be realized. Inventory acquired prior to receipt of marketing approval of a product candidate is expensed as research and development expense as incurred. Inventory that can be used in either the production of clinical or commercial product is expensed as research and development expense when selected for use in a clinical manufacturing campaign. Inventory produced that will be used in promotional marketing campaigns is expensed to selling and marketing expense when it is selected for use in a marketing program. ​ Fair Value Measurements ​ Certain assets and liabilities are carried at fair value under GAAP. Fair value is defined as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. Valuation techniques used to measure fair value must maximize the use of observable inputs and minimize the use of unobservable inputs. Financial assets and liabilities carried at fair value are to be classified and disclosed in one of the following three levels of the fair value hierarchy, of which the first two are considered observable and the last is considered unobservable: ​ ● Level 1—Quoted prices in active markets for identical assets or liabilities. ​ ● Level 2—Observable inputs (other than Level 1 quoted prices) such as quoted prices in active markets for similar assets or liabilities, quoted prices in markets that are not active for identical or similar assets or liabilities, or other inputs that are observable or can be corroborated by observable market data. ​ ● Level 3—Unobservable inputs that are supported by little or no market activity and that are significant to determining the fair value of the assets or liabilities, including pricing models, discounted cash flow methodologies and similar techniques. ​ Derivative Instruments ​ The Company recognizes all derivative instruments as either assets or liabilities at fair value through profit or loss on the Company's consolidated balance sheet. Changes in the estimated fair value of derivative instruments are recognized in other income (expense), net in the consolidated statements of operations and comprehensive loss. F-12 Table of Contents If the Company determines that a financial or non-financial contract, a ‘host contract’, includes implicit or explicit terms that affect the cash flows of the contract in a manner similar to a stand-alone derivative instrument, an ‘embedded derivative’, the Company analyzes whether to account for the embedded derivative separately. The Company accounts for an embedded derivative not separately from the host contract if it is clearly and closely related to the host contract or if the entire contract is measured at fair value through profit or loss. In other cases, the Company accounts for an embedded derivative separately. ​ The 2026 Convertible Notes, as discussed in Note 9, allow the holders to convert all or part of the outstanding principal of their 2026 Convertible Notes into shares of the Company’s common stock provided that no conversion results in a holder beneficially owning more than 19.99 % of the issued and outstanding common stock of the Company. The entire embedded conversion option is required to be separated from the 2026 Convertible Notes and accounted for as a freestanding derivative instrument subject to derivative accounting. The main input when determining the fair value of the 2026 Convertible Notes is the bond yield that pertains to the host instrument without the conversion option. The significant assumption used in determining the bond yield is the market yield movements of a comparable instrument issued as of the valuation date, which is assessed and updated each period. Therefore, the entire conversion option is bifurcated from the underlying debt instrument and accounted for and valued separately from the host instrument. The Company measures the value of the embedded conversion option at its estimated fair value and recognizes changes in the estimated fair value in other income (expense), net in the consolidated statements of operations and comprehensive loss during the period of change. The embedded conversion is recognized as a derivative liability in the Company’s consolidated balance sheet. Property and Equipment ​ Property and equipment are stated at cost less accumulated depreciation. Depreciation expense is recognized using the straight-line method over a three - to five-year estimated useful life. Leasehold improvements are amortized over the shorter of the lease term or the estimated useful life of the related asset. Expenditures for repairs and maintenance of assets are charged to expense as incurred. Upon retirement or sale, the cost and related accumulated depreciation of assets disposed of are removed from the accounts and any resulting gain or loss is included in loss from operations. ​ Leases ​ The Company determines whether an arrangement is or contains a lease at inception. Operating leases are recognized on the consolidated balance sheets as operating lease assets, current portion of lease liabilities and long-term lease liabilities. Operating lease assets represent the Company’s right to use an underlying asset for the lease term and lease liabilities represent the Company’s obligation to make lease payments arising from the lease. Operating lease liabilities and their corresponding operating lease assets are recorded based on the present value of lease payments over the expected remaining lease term. The operating lease assets also include any lease payments made and adjustments for prepayments and lease incentives. The interest rate implicit in lease contracts is typically not readily determinable. As a result, the Company utilized its incremental borrowing rate, which is the rate incurred to borrow on a collateralized basis over a similar term an amount equal to the lease payments in a similar economic environment. Lease terms may include options to extend or terminate the lease when it is reasonably certain that the Company will exercise that option. The Company reassesses the lease term and remeasures the lease liability if triggering events occur. Lease expense for lease payments is recognized on a straight-line basis over the lease term. Impairment of Long-Lived Assets ​ Long-lived assets consist of property and equipment and right-of-use assets. Long-lived assets to be held and used are tested for recoverability whenever events or changes in business circumstances indicate that the carrying amount of the assets may not be fully recoverable. Factors that the Company considers in deciding when to perform an impairment review include significant underperformance of the business in relation to expectations, significant negative industry or economic trends, and significant changes or planned changes in the use of the assets. If an impairment review is performed to evaluate a long-lived asset for recoverability, the Company compares forecasts of undiscounted cash flows expected to result from the use and eventual disposition of the long-lived asset to its carrying value. An impairment loss would be recognized when estimated undiscounted future cash flows expected to result from the use of an asset are less than its carrying amount. The impairment loss would be based on the excess of the carrying value of the impaired asset over its fair value, determined based on discounted cash flows. The Company has had no impairment triggers of long-lived assets. F-13 Table of Contents ​ Research and Development Costs ​ Research and development costs are expensed as incurred. Included in research and development expenses are salaries, stock-based compensation and benefits of employees and other operational costs related to the Company’s research and development activities, including external costs of outside vendors engaged to conduct preclinical studies and clinical trials, manufacturing costs of the Company’s products prior to regulatory approval, costs related to collaboration agreements and facility-related expenses. ​ The Company records accruals for estimated ongoing research and development costs. When evaluating the adequacy of the accrued liabilities, the Company analyzes progress of the studies, including the phase or completion of events, invoices received and contracted costs. Judgments and estimates are made in determining the accrued balances at the end of any reporting period. Actual results could differ from the Company’s estimates. The Company’s historical accrual estimates have not been materially different from the actual costs. ​ Advertising Costs ​ Advertising costs are expensed as incurred. ​ ​ Accounting for Stock-Based Compensation ​ The Company measures all stock options and other stock-based awards granted to employees, directors, and nonemployees at the fair value on the date of the grant. The fair value of the awards is recognized as expense, net of estimated forfeitures, over the requisite service period, which is generally the vesting period of the respective award. The straight-line method of expense recognition is applied to all awards with service-only conditions. ​ The Company recognizes compensation expense for only the portion of awards that are expected to vest. In developing a forfeiture rate estimate, the Company has considered its historical experience to estimate pre-vesting forfeitures for service-based awards. The impact of a forfeiture rate adjustment will be recognized in full in the period of adjustment, and if the actual forfeiture rate is materially different from the Company’s estimate, the Company may be required to record adjustments to stock-based compensation expense in future periods. ​ Compensation cost related to shares purchased through the Company’s employee stock purchase plan, which is considered compensatory, is based on the estimated fair value of the shares on the offering date, including consideration of the discount and the look-back period. The Company estimates the fair value of the shares using a Black-Scholes option pricing model. Compensation expense is recognized over the six -month withholding period prior to the purchase date. ​ The Company classifies stock-based compensation expense in its consolidated statement of operations and comprehensive loss in the same manner in which the award recipient’s payroll costs are classified or in which the award recipient’s service payments are classified. ​ Income Taxes ​ The Company accounts for income taxes using the asset and liability method, which requires the recognition of deferred tax assets and liabilities for the expected future tax consequences of events that have been recognized in the consolidated financial statements or in the Company’s tax returns. Deferred taxes are determined based on the difference between the financial statement and tax basis of assets and liabilities using enacted tax rates in effect in the years in which the differences are expected to reverse. Changes in deferred tax assets and liabilities are recorded in the provision for income taxes. The Company assesses the likelihood that its deferred tax assets will be recovered from future taxable income and, to the extent it believes, based upon the weight of available evidence, that it is more likely than not that all or a portion of deferred tax assets will not be realized, a valuation allowance is established through a charge to income tax expense. ​ The Company accounts for uncertainty in income taxes recognized in the consolidated financial statements by applying a two-step process to determine the amount of tax benefit to be recognized. First, the tax position must be evaluated to determine the likelihood that it will be sustained upon external examination by the taxing authorities. If the F-14 Table of Contents tax position is deemed more-likely-than-not to be sustained, the tax position is then assessed to determine the amount of benefit to recognize in the consolidated financial statements. The amount of the benefit that may be recognized is the largest amount that has a greater than 50% likelihood of being realized upon ultimate settlement. The provision for income taxes includes the effects of any resulting tax reserves, or unrecognized tax benefits, that are considered appropriate. ​ Interest and penalties related to income taxes are recorded as part of the income tax provision. ​ ​ Segment Data ​ The Company manages its operations as a single segment for the purposes of assessing performance and making operating decisions. The Company’s singular focus is on advancing its bioresorbable hydrogel product candidates for the programed-release delivery of therapeutic agents, specifically for ophthalmology. All property and equipment, net and all operating lease assets are held in the United States. All product revenue, net is attributable to the United States. Collaboration revenue is attributable to a customer in China (Note 3). ​ Comprehensive Loss ​ Comprehensive loss includes net loss as well as other changes in stockholders’ equity (deficit) that result from transactions and economic events other than those with stockholders. For the years ended December 31, 2022, 2021 and 2020, there were no items that gave rise to other comprehensive loss and therefore, there was no difference between net loss and comprehensive loss. ​ Net Loss Per Share ​ Basic net loss per share attributable to common stockholders is computed by dividing the net loss attributable to common stockholders by the weighted average number of shares of common stock outstanding for the period. Diluted net loss attributable to common stockholders is computed by adjusting net loss attributable to common stockholders to reallocate undistributed earnings based on the potential impact of dilutive securities, outstanding stock options and common stock warrants, except where the result would be anti-dilutive. Diluted net loss per share attributable to common stockholders is computed by dividing the diluted net loss attributable to common stockholders by the weighted average number of common shares outstanding for the period, including potential dilutive common shares assuming the dilutive effect of the conversion of convertible debt securities, the exercise of outstanding stock options and common stock warrants. In the diluted net loss per share calculation, net loss would also be adjusted for the elimination of interest expense on convertible debt securities and the mark-to-market gain or loss on bifurcated conversion options, if the impact was not anti-dilutive. ​ Recently Adopted Accounting Pronouncements ​ In August 2020, the FASB issued ASU No. 2020-06, Debt – Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging—Contracts in Entity’s Own Equity (Subtopic 815-40) (“ASU 2020-06”). This standard amends the guidance on convertible instruments and the derivatives scope exception for contracts in an entity’s own equity and improves and amends the related earnings per share guidance for both Subtopics. The amendments in the ASU are effective for public business entities that meet the definition of an SEC filer, excluding entities eligible to be smaller reporting companies as defined by the SEC, for fiscal years beginning after December 15, 2021, including interim periods within those fiscal years. The Company adopted this accounting pronouncement as required effective January 1, 2022 and its adoption did not have a material impact on the consolidated financial statements. ​ Recently Issued Accounting Pronouncements From time to time, new accounting pronouncements are issued by the FASB and adopted by us as of the specified effective date. The Company believes that recently issued accounting pronouncements that are not yet effective will not have a material impact on our consolidated financial statements and disclosures. ​ F-15 Table of Contents 3. Licensing Agreements and Deferred Revenue ​ Incept License Agreement (in-licensing) ​ On September 13, 2018, the Company entered into a second amended and restated license agreement (the “Second Amended Agreement”) with Incept, LLC (“Incept”) to use and develop certain intellectual property (the “Incept License”). Under the Incept License, as amended and restated, the Company was granted a worldwide, perpetual, exclusive license to develop and commercialize products that are delivered to or around the human eye for diagnostic, therapeutic or prophylactic purposes relating to ophthalmic diseases or conditions. The Company is obligated to pay low single-digit royalties on net sales of commercial products developed using the licensed technology, commencing with the date of the first commercial sale of such products and until the expiration of the last to expire of the patents covered by the license. Any of the Company’s sublicensees also will be obligated to pay Incept a royalty equal to a low single-digit percentage of net sales made by it and will be bound by the terms of the agreement to the same extent as the Company. The Company is obligated to reimburse Incept for its share of the reasonable fees and costs incurred by Incept in connection with the prosecution of the patent applications licensed to the Company under the Incept License. ​ Royalties paid under this agreement related to product sales were $ 1,466 , $ 1,333 and $ 269 for the years ended December 31, 2022, 2021 and 2020, respectively. Royalties have been charged to cost of product revenue. ​ AffaMed License Agreement (out-licensing) ​ On October 29, 2020, the Company entered into license agreement (“License Agreement”) with AffaMed Therapeutic Limited (“AffaMed”) for the development and commercialization of the Company’s DEXTENZA product regarding ocular inflammation and pain following cataract surgery and allergic conjunctivitis (collectively, the “DEXTENZA Field”) and for the Company’s OTX-TIC product candidate (collectively with DEXTENZA, the “AffaMed Licensed Products”) regarding open-angle glaucoma or ocular hypertension (collectively, the “TIC Field” and, with the DEXTENZA Field, each a “Field”), in each case in mainland China, Taiwan, Hong Kong, Macau, South Korea, and the countries of the Association of Southeast Asian Nations (collectively, the “Territories”). The Company retains development and commercialization rights for the AffaMed Licensed Products in the rest of the world. ​ Under the License Agreement, the Company received a non-refundable upfront payment of $ 12,000 in December 2020, a $ 1,000 milestone in the fourth quarter of 2021 and a $ 2,000 clinical support payment in the second quarter of 2022. The Company is also eligible to receive up to an additional $ 88,000 in aggregate upon the achievement of certain regulatory, development and commercial milestones. The Company is also entitled to receive tiered, escalating royalties on the net sales of the AffaMed Licensed Products ranging from a low-teen to low-twenties percentage. Royalties under the License Agreement are payable on an AffaMed Licensed Product-by-AffaMed Licensed Product and jurisdiction-by-jurisdiction basis and are subject to potential reductions in specified circumstances, subject to a specified floor. ​ Under the License Agreement, the Company is generally responsible for expenses related to the development of the AffaMed Licensed Products in the applicable Fields in the Territories, provided that AffaMed (i) reimburse the Company a low-teen percentage of expenses incurred in connection with certain clinical trials conducted by the Company and designed to support marketing approval of the AffaMed Licensed Product by the FDA or the European Medicines Agency (“Global Studies”); (ii) is solely responsible for expenses incurred in connection with territory-specific clinical trials that it conducts in furtherance of the development plan agreed between the parties in the applicable Fields in the Territories (“Local Studies”); and (iii) reimburse the Company in full for expenses incurred in connection with obtaining and maintaining regulatory approvals of the AffaMed Licensed Products in the applicable Fields in the Territories. In the event AffaMed declines to participate in a Global Study or to conduct a Local Study in any jurisdiction in which the Company determines to conduct such a study, the Company is relieved of its obligation to provide AffaMed clinical data from such study, other than safety data, unless AffaMed subsequently reimburses the Company in the amounts described above plus a prespecified premium. ​ The License Agreement expires upon the expiration of the last royalty term for the last AffaMed Licensed Product in any applicable Field in the Territories. Either party may, subject to specified cure periods, terminate the License Agreement in the event of the other party’s uncured breach. Either party may also terminate the License Agreement under specified circumstances relating to the other party’s insolvency. AffaMed has the right to terminate the License Agreement at any time after completion of a Phase 3 clinical trial for OTX-TIC for any or no reason upon providing the Company three months’ notice. During an established period following its change of control or its entry into a global F-16 Table of Contents licensing agreement that includes the Territories with a third party, the Company has the option to terminate the License Agreement, subject to a specified notice period and the repayment of any costs and expenses incurred by AffaMed in connection with the License Agreement, including upfront and milestone payments AffaMed has previously paid to the Company, at a prespecified premium. ​ The Company concluded that AffaMed is a customer in this arrangement, and as such, the arrangement falls within the scope of the revenue recognition guidance in ASC 606. ​ At the inception of the License Agreement, the Company identified the following performance obligations in the agreement: ​ ● the license, regulatory filings and manufacturing of DEXTENZA (the “DEXTENZA Field performance obligation”); ​ ● the license, regulatory filings and manufacturing for the Company’s OTX-TIC product candidate regarding open-angle glaucoma or ocular hypertension in the Territories (the “OTX-TIC Field performance obligation”); ​ ● the conduct of a Phase 2 clinical trial of OTX-TIC (the “Phase 2 Clinical Trial of OTX-TIC performance obligation”); and ​ ● obligations to participate on various joint research, development and project committees; the Company has concluded that this performance obligation is not material. ​ The transaction price was allocated to the performance obligations based on the relative estimated standalone selling prices of each performance obligation. ​ The Company developed the estimated standalone selling price for the services and/or manufacturing and supply included in each of the performance obligations, as applicable, primarily based on the nature of the services to be performed and/or goods to be manufactured and estimates of the associated costs, adjusted for a reasonable profit margin that would be expected to be realized under similar contracts. ​ The Company has determined that any sales-based royalties and milestones will be recognized as the Company delivers the clinical and commercial manufactured product to AffaMed. Any changes in estimates may result in a cumulative catch-up based on the number of units of manufactured product delivered. ​ As of December 31, 2022, the transaction price was determined to be $ 15,000 . All potential regulatory, development and commercial milestone payments in the amount of $ 88,000 did not meet the recognition criteria under the most likely method, because their achievement was highly dependent on factors outside the control of the Company and therefore, were excluded from the transaction price as of December 31, 2022. Furthermore, under the expected value method the Company excluded the potential royalties from the transaction price. ​ We recognize revenue related to the amounts allocated to the DEXTENZA Field performance obligation and the OTX-TIC Field performance obligation based on the point in time upon which control of supply is transferred to AffaMed for each delivery of the associated supply. The Company currently expects to recognize the revenue over a period of approximately seven to eight years commencing on the date the Company begins delivering product to AffaMed. This estimate of this period considers the timing of development and commercial activities under the License Agreement and may be reduced or increased based on the various activities as directed by the joint committees, decisions made by AffaMed, regulatory feedback or other factors not currently known. ​ The Company recognized $ 1,037 , $ 0 and $ 0 of collaboration revenue related to the Phase 2 Clinical Trial of OTX-TIC performance obligation for the years ended December 31, 2022, 2021 and 2020, respectively. ​ As of December 31, 2022, the aggregate amount of the transaction price allocated to the partially unsatisfied Phase 2 Clinical Trial of OTX-TIC performance obligation was $ 963 . This amount is expected to be recognized as this performance obligation is satisfied through June 2025. ​ F-17 Table of Contents Deferred revenue activity for the year ended December 31, 2022 was as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ Deferred Revenue Deferred revenue at December 31, 2021 ​ $ 13,000 Additions ​ ​ 2,000 Amounts recognized into revenue ​ ​ ( 1,037 ) Deferred revenue at December 31, 2022 ​ $ 13,963 ​ ​ ​ ​ ​ Regeneron Collaboration Agreement ​ On October 10, 2016, the Company entered into a Collaboration, Option and License Agreement (the “Regeneron Collaboration Agreement”) with Regeneron Pharmaceuticals, Inc. (“Regeneron”) for the development and potential commercialization of products using the Company’s hydrogel in combination with Regeneron’s large molecule VEGF-targeting compounds for the treatment of retinal diseases. ​ Under the terms of the Collaboration Agreement, the Company and Regeneron had agreed to conduct a joint research program with the aim of developing a sustained-release formulation of aflibercept, currently marketed under the tradename Eylea, that is suitable for advancement into clinical development. The Company had granted Regeneron an option (the “Option”) to enter into an exclusive, worldwide license to develop and commercialize products using the Company’s hydrogel in combination with Regeneron’s large molecule VEGF-targeting compounds (“Licensed Products”). Under the term of the Collaboration Agreement, Regeneron was responsible for funding an initial preclinical tolerability study. The Regeneron Collaboration Agreement was subsequently amended on May 8, 2020 (the “Regeneron Amendment”). Pursuant to the Regeneron Amendment, the Company and Regeneron had adopted a new work plan to transition joint efforts under the Regeneron Collaboration Agreement to the research and development of an extended-delivery formulation of aflibercept to be delivered to the suprachoroidal space. Regeneron had agreed to pay personnel and material costs of the Company for specified preclinical development activities in connection with the revised work plan, as well as certain other costs. In addition, the Regeneron Amendment provided for the modification of the terms of the Option previously granted to Regeneron under the Regeneron Collaboration Agreement. As amended, the Option was exclusive for twenty-four months following May 8, 2020. On August 5, 2021, Regeneron notified the Company of its termination of the Regeneron Collaboration Agreement, as amended. The termination became effective immediately. In connection with the termination of the Regeneron Collaboration Agreement, all licenses, options and other rights granted to either party under the Regeneron Collaboration Agreement automatically terminated, other than the surviving joint intellectual property rights described below. The Company and Regeneron also became obligated to undertake certain transition activities upon the termination, including the return of specified property of the other party. Each party retains an equal, undivided ownership interest, which may be transferred, licensed and otherwise exploited without a duty to account to the other party, in certain intellectual property rights jointly developed under the collaboration. As a result of the termination, the Company is no longer eligible to receive (i) reimbursement from Regeneron for ongoing research and development activities, (ii) a fee upon exercise of the Option, (iii) payments upon the achievement of specified development and regulatory milestones of the Regeneron Licensed Products, or (iv) tiered, escalating royalties in a range from a high-single digit to a low-to-mid teen percentage of net sales of Regeneron Licensed Products, in each case pursuant to the Regeneron Collaboration Agreement. The Company is also no longer obligated to reimburse Regeneron for certain development costs, up to an aggregate amount of $ 30,000 in certain circumstances, were Regeneron to have exercised the Option. For the years ended December 31, 2022, 2021 and 2020, the Company had recorded $ 0 , $ 768 and $ 1,256 related to work performed for preclinical development activities in connection with the revised work plan which the Company has recorded as a reduction of research and development expense as this research is not an output of the Company’s ordinary business activities. As of December 31, 2022 and 2021, the Company had not recorded any assets or liabilities with regard to the Regeneron Collaboration Agreement. ​ ​ F-18 Table of Contents 4. Cash Equivalents and Restricted Cash ​ The Company’s statements of cash flows include restricted cash with cash and cash equivalents when reconciling the beginning-of-period and end-of-period total amounts shown on such statements. A reconciliation of the cash, cash equivalents, and restricted cash reported within the balance sheet that sum to the total of the same amounts shown in the statement of cash flows is as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ December 31, ​ ​ December 31, ​ 2022 2021 2020 Cash and cash equivalents ​ $ 102,300 ​ $ 164,164 ​ $ 228,057 Restricted cash ​ ​ 1,764 ​ ​ 1,764 ​ ​ 1,764 Total cash, cash equivalents and restricted cash as shown on the statements of cash flows ​ $ 104,064 ​ $ 165,928 ​ $ 229,821 ​ As of December 31, 2022, 2021 and 2020, the Company held restricted cash of $ 1,764 , respectively, on its consolidated balance sheet. The Company held restricted cash as security deposits for its real estate leases. 5. Inventory ​ Inventory consisted of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ December 31, ​ ​ 2022 2021 Raw materials ​ $ 309 ​ $ 388 ​ Work-in-process ​ ​ 899 ​ ​ 605 ​ Finished goods ​ 766 ​ 257 ​ ​ ​ $ 1,974 ​ $ 1,250 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 6. Property and Equipment, net ​ Property and equipment, net consisted of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ December 31, ​ 2022 2021 Equipment ​ $ 12,485 ​ $ 10,989 Leasehold improvements ​ 9,074 ​ 9,074 Furniture and fixtures ​ 1,268 ​ 1,286 Software ​ 236 ​ 236 Construction in progress ​ 4,071 ​ 578 ​ ​ 27,134 ​ 22,163 Less: Accumulated depreciation and amortization ​ ( 17,278 ) ​ ( 15,207 ) ​ ​ $ 9,856 ​ $ 6,956 ​ Depreciation and amortization expense was $ 2,109 , $ 2,421 and $ 2,773 for the years ended December 31, 2022, 2021 and 2020, respectively. 7 . Leases ​ The Company leases real estate, including laboratory, manufacturing and office space. The Company’s leases have remaining lease terms ranging from less than 1 year to approximately 4.5 years. Certain leases include one or more options to renew , exercised at the Company’s sole discretion, with renewal terms that can extend the lease term from one year to six years . All of the Company’s leases qualify as operating leases. ​ The lease for the Company’s 20,445 square feet of manufacturing space located at 36 Crosby Drive in Bedford, Massachusetts commenced on June 30, 2018 and is scheduled to expire on July 31, 2023. On October 18, 2022, the F-19 Table of Contents Company exercised its option to extend the lease agreement by an additional five -year term, resulting in a new expiration date of July 31, 2028. Under the terms of the existing lease, rent for the five -year extension period will be based on the current fair market rent for comparable space in the building and in other similar buildings in the same rental market as of August 1, 2023, the commencement date of the additional five -year term. We have estimated the prevailing market rental rates at the time when we exercised the renewal option, and have included these in our remeasurement of the operating lease asset and the lease liability. This has resulted in an increase of the Operating lease assets and Operating lease liabilities of $ 4,284 as of the remeasurement date. As this is an estimate for variable payments that depend on an index or a rate, we will not remeasure the payments for the five -year renewal period even if actual rent as of the commencement date of the five -year extension term, August 1, 2023, is different from our estimate. ​ ​ The lease for approximately 70,712 square feet of general office, research and development and manufacturing space located at 15 Crosby Drive in Bedford, Massachusetts. The lease term commenced on February 1, 2017 and will expire on July 31, 2027. The Company has the option to extend the lease for two additional periods of five years each by delivering written notice of the exercise not earlier than fifteen months nor later than 12 months before expiration of the original term. ​ The lease for 30,036 square feet of office space located at 24 Crosby Drive in Bedford, Massachusetts commenced on April 18, 2019 and terminates on March 24, 2024 and does not include any lease renewal options . ​ Recognized lease costs were as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ For the ​ For the ​ For the ​ ​ Year Ended ​ Year Ended ​ Year Ended ​ ​ December 31, ​ December 31, ​ December 31, ​ ​ 2022 ​ 2021 ​ 2020 Operating lease costs ​ $ 2,369 ​ $ 2,482 ​ $ 2,418 Variable lease costs ​ ​ 756 ​ ​ 629 ​ ​ 677 Total lease costs ​ $ 3,125 ​ $ 3,111 ​ $ 3,095 ​ The minimum lease payments for the next five years and thereafter are expected to be as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, Year Ending December 31, ​ ​ 2022 2023 ​ ​ ​ ​ 2,663 2024 ​ ​ ​ ​ 2,796 2025 ​ ​ ​ ​ 2,674 2026 ​ ​ ​ ​ 2,709 2027 ​ ​ ​ ​ 2,111 Thereafter ​ ​ ​ ​ 716 Total lease payments ​ ​ ​ $ 13,669 Less: interest ​ ​ ​ ​ 3,392 Present value of operating lease liabilities ​ ​ ​ $ 10,277 ​ The following table summarizes the weighted average remaining lease term and the weighted average incremental borrowing rate used to determine the operating lease liability: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ ​ December 31, ​ 2022 ​ ​ 2021 Weighted average remaining lease term in years ​ ​ 4.9 ​ ​ 4.8 ​ Weighted average discount rate ​ ​ 13.41 % ​ 13.55 % ​ F-20 Table of Contents Supplemental disclosure of cash flow information related to the Company’s operating leases included in cash flows provided by operating activities in its consolidated statements of cash flows is as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ For the ​ ​ For the ​ For the ​ ​ Year Ended ​ ​ Year Ended ​ Year Ended ​ ​ December 31, ​ ​ December 31, ​ December 31, ​ 2022 ​ ​ 2021 ​ 2020 Cash paid for amounts included in the measurement of lease liabilities ​ $ 2,549 ​ $ 2,482 ​ $ 2,418 ​ ​ 8. Expenses ​ The Company recognized $ 1,166 , $ 1,925 , and $ 1,344 of advertising expenses for the years ended December 31, 2022, 2021 and 2020, respectively. ​ Accrued expenses consisted of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ December 31, ​ 2022 2021 Accrued payroll and related expenses ​ $ 7,509 ​ $ 6,597 Accrued rebates and programs ​ ​ 3,560 ​ ​ 3,615 Accrued professional fees ​ 1,228 ​ 1,227 Accrued research and development expenses ​ 1,816 ​ 1,102 Accrued interest payable on 2026 convertible notes ​ 8,756 ​ 6,475 Accrued other ​ 1,228 ​ 1,105 ​ ​ $ 24,097 ​ $ 20,121 ​ ​ ​ ​ ​ ​ ​ ​ 9. Financial Liabilities ​ Convertible Notes ​ On March 1, 2019, the Company issued $ 37,500 of convertible notes which accrue interest at an annual rate of 6 % of their outstanding principal amount, which is payable, along with the principal amount at maturity, on March 1, 2026, unless earlier converted, repurchased or redeemed (the “2026 Convertible Notes”). The Company presents accrued interest in accrued current liabilities because the notes are currently convertible and the interest is payable in cash. The effective annual interest rate for the 2026 Convertible Notes was 14.8 % through December 31, 2022. ​ The holders of the 2026 Convertible Notes may convert all or part of the outstanding principal amount of their 2026 Convertible Notes into shares of the Company’s common stock, par value $ 0.0001 per share, prior to maturity and provided that no conversion results in a holder beneficially owning more than 19.99 % of the issued and outstanding common stock of the Company. The conversion rate is initially 153.8462 shares of the Company’s common stock per $ 1,000 principal amount of the 2026 Convertible Notes, which is equivalent to an initial conversion price of $ 6.50 per share. The conversion rate is subject to adjustment in customary circumstances such as stock splits or similar changes to the Company’s capitalization. ​ Upon conversion by the holder, other than a conversion based on a Corporate Transactions as defined below, the Company has the right to select the settlement of the conversion in either shares of common stock, cash, or in a combination thereof. Upon any conversion of any 2026 Convertible Note, the Company is obligated to make a cash payment to the holder of such 2026 Convertible Note for any interest accrued but unpaid on the principal amount converted. ​ ● If the Company elects to satisfy such conversion by shares of common stock, the Company shall deliver to the converting holder in respect of each $ 1,000 principal amount of 2026 Convertible Notes being converted a number of common shares equal to the conversion rate in effect on the conversion date; F-21 Table of Contents ​ ● If the Company elects to satisfy such conversion by cash settlement, the Company shall pay to the converting holder in respect of each $ 1,000 principal amount of 2026 Convertible Notes being converted cash in an amount equal to the sum of the Daily Conversion Values (as defined below) for each of the twenty (20) consecutive trading days during a specified period. The “Daily Conversion Values” is defined as each of the 20 consecutive trading days during the specified period, 5.0 % of the product of (a) the conversion rate on such trading day and (b) the “Daily VWAP” on such trading day. The Daily VWAP is defined as each of the 20 consecutive trading days during the applicable Observation Period, the per share volume-weighted average price as displayed under the heading “Bloomberg VWAP” on the Bloomberg page for the Company. ​ ● If the Company elects to satisfy such conversion by combination, the Company shall pay or deliver, as the case may be, in respect of each $ 1,000 principal amount of 2026 Convertible Notes being converted, a settlement amount equal to the sum of the “Daily Settlement Amounts” (as defined below) for each of the twenty (20) consecutive trading days during the specified period. The “Daily Settlement Amount” is defined as, for each of the 20 consecutive trading days during the specified period: (a) cash in an amount equal to the lesser of (i) the Daily Measurement Value (as defined below) and (ii) the Daily Conversion Value on such Trading Day; and (b) if the Daily Conversion Value on such trading day exceeds the Daily Measurement Value, a number of Shares equal to (i) the difference between the Daily Conversion Value and the Daily Measurement Value, divided by (ii) the Daily VWAP for such Trading Day. The “Daily Measurement Value” is defined as the Specified Dollar Amount (as defined below), if any, divided by 20. The “Specified Dollar Amount” is defined as the maximum cash amount per $ 1,000 principal amount of Notes to be received upon conversion as specified in the notice specifying the Company’s chosen settlement method. In the event of a Corporate Transaction, the noteholder shall have the right to either (a) convert all of the unpaid principal at the conversion rate and receive a cash payment equal to (i) the outstanding accrued but unpaid interest under the 2026 Convertible Note to, but excluding, the corporate transaction conversion date (to the extent such date occurs prior to March 1, 2026, the maturity date of the 2026 Convertible Notes) plus (ii) and an additional amount of consideration based on a sliding scale depending on the date of such as Corporate transaction or (b) require the Company to repurchase all or part of the outstanding principal amount of such 2026 Convertible Note at a repurchase price equal to 100 % of the outstanding principal amount of the 2026 Convertible Note to be repurchased, plus accrued and unpaid interest to, but excluding, the repurchase date. ​ A corporate transaction includes (i) a merger or consolidation executed through a tender offer or change of control (other than one in which stockholders of the Company own a majority by voting power of the outstanding shares of the surviving or acquiring corporation); (ii) a sale, lease, transfer, of all or substantially all of the assets of the Company; or (iii) if the Company’s common stock ceases to be listed or quoted on any of the New York Stock Exchange, the Nasdaq Global Select Market, the Nasdaq Global Market or the Nasdaq Capital Market (the “Corporate Transaction”). ​ If the last reported sale price of the common stock has been at least 130 % of the conversion rate then in effect for 20 of the preceding 30 trading days (including the last trading day of such period), the Company is entitled, at its option, to redeem all or part of the outstanding principal amount of the 2026 Convertible Notes, on a pro rata basis, at an optional redemption price equal to 100 % of the outstanding principal amount of the 2026 Convertible Notes to be redeemed, plus accrued and unpaid interest to, but excluding, the optional redemption date. ​ The 2026 Convertible Notes are subject to acceleration upon the occurrence of specified events of default, including a default or breach of certain contracts material to the Company and the delisting and deregistration of the Company’s common stock. ​ The Company determined that the embedded conversion option is required to be separated from the 2026 Convertible Notes and accounted for as a freestanding derivative instrument subject to derivative accounting. The allocation of proceeds to the conversion option results in a discount on the 2026 Convertible Notes. The Company is amortizing the discount to interest expense over the term of the 2026 Convertible Notes using the effective interest method. ​ F-22 Table of Contents A summary of the 2026 Convertible Notes at December 31, 2022 and 2021 is as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ December 31, ​ 2022 2021 2026 Convertible Notes ​ $ 37,500 ​ $ 37,500 Less: unamortized discount ​ ​ ( 8,751 ) ​ ​ ( 11,065 ) Total ​ $ 28,749 ​ $ 26,435 ​ Notes Payable ​ The Company entered into a credit and security agreement in 2014 (as amended to date, the “Credit Agreement”) establishing the Company’s credit facility (the “Credit Facility”). ​ In December 2018, the Company’s total indebtedness under the Credit Facility was increased to $ 25,000 . The Company was required to make interest-only payments under the Credit Facility until December 2020. Commencing in January 2021, the Company was required to make 36 equal monthly installments of principal in the amount of $ 694 , plus interest, through December 2023. Amounts borrowed under the Credit Facility were at LIBOR base rate, subject to 2.00 % floor, plus 7.25 %. Prior to the Fourth Amendment (as defined below), the effective interest rate was 9.25 % . ​ In June 2021, the Company entered into a Fourth Amended and Restated Credit and Security Agreement (the “Fourth Amendment”) to amend the terms of its debt with existing lenders for total indebtedness of $ 20,833 and borrowed an incremental $ 4,167 , for a total of $ 25,000 (the “2021 Amended Credit Facility”). The Company is required to make interest-only payments under the 2021 Amended Credit Facility through April 2024. Commencing in May 2024, the Company is required to make 19 equal monthly installments of principal in the amount of $ 1,042 , plus interest, then on the maturity date, November 30, 2025 the remaining balance of $ 5,208 plus the exit fee, as defined below. In the event the Company achieves certain milestones under the 2021 Amended Credit Facility, the Company has the right to extend through April 1, 2026 and make 5 equal monthly installments of principal in the amount of $ 1,042 , plus interest. The Company has not assumed the achievement of these milestones for purposes of disclosures herein. Amounts borrowed under the 2021 Amended Credit Facility are at LIBOR base rate, subject to 1.00 % floor, plus 6.75 %. The interest rate on the date of the amendment was 8.8 %. In addition, a final payment (exit fee) equal to 3.5 % of amounts drawn under the Amended Credit Facility, or $ 875 based on borrowings of $ 25,000 , is due upon the maturity date of November 30, 2025. The Company is accruing the exit fee through November 30, 2025. ​ The Company accounted for the Fourth Amendment as a modification in accordance with the guidance in ASC 470-50, Debt. Amounts paid to the lenders were recorded as debt discount and a new effective interest rate was established. The effective annual interest rate of the outstanding debt under the Fourth Amendment is 8.8 % . ​ There are no financial covenants associated with the Fourth Amendment. However, the Fourth Amendment does contain negative covenants restricting the Company’s activities, including limitations on dispositions, mergers or acquisitions; encumbering its intellectual property; incurring indebtedness or liens; paying dividends; making certain investments; and engaging in certain other business transactions. As of December 31, 2022, the Company was not in violation of any of its covenants under the Fourth Amendment. The obligations under the Fourth Amendment are subject to acceleration upon the occurrence of specified events of default, including a material adverse change in the Company’s business, operations or financial or other condition. The debt is collateralized by substantially all of the Company’s assets, including its intellectual property. ​ In accordance with the Credit Agreement, in connection with the Company’s desire to issue and sell the 2026 Convertible Notes, the Company amended the terms of its debt with existing lenders in February 2019. The amendment added to the Credit Agreement, among other provisions, a negative covenant restricting the Company from paying the holders of the 2026 Convertible Notes ahead in priority to the existing lenders, for so long as indebtedness remains outstanding under the Credit Facility, and a cross-default provision to establish that an event of default under the purchase agreement for the 2026 Convertible Notes also constitutes an event of default under the Credit Agreement. ​ The Company has a total borrowing capacity of $ 25,000 under the 2021 Amended Credit Facility, which was fully drawn down as of December 31, 2022. ​ F-23 Table of Contents Borrowings outstanding are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, December 31, ​ 2022 2021 Borrowings outstanding ​ $ 25,000 ​ $ 25,000 Accrued exit fee ​ ​ 335 ​ ​ 110 Unamortized discount ​ ​ ( 78 ) ​ ​ ( 110 ) Long-term notes payable ​ $ 25,257 ​ $ 25,000 ​ As of December 31, 2022, the annual repayment requirements for the Credit Facility, inclusive of the final payment of $ 875 due at expiration, were as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ending December 31, Principal Final Payment Total 2023 ​ ​ — ​ ​ — ​ ​ — 2024 ​ ​ 8,333 ​ ​ — ​ ​ 8,333 2025 ​ ​ 16,667 ​ ​ 875 ​ ​ 17,542 ​ ​ $ 25,000 ​ $ 875 ​ $ 25,875 ​ ​ 10. Derivatives ​ Derivative Liability ​ The 2026 Convertible Notes (Note 9) contain an embedded conversion option that meets the criteria to be bifurcated and accounted for separately from the 2026 Convertible Notes (the "Derivative Liability"). The Derivative Liability was recorded at fair value upon the issuance of the 2026 Convertible Notes and is subsequently remeasured to fair value at each reporting period. The 2026 Convertible Notes, including the Derivative Liability, were initially valued and are remeasured using a "with-and-without" method. The "with-and-without" methodology involves valuing the whole instrument on an as-is basis and then valuing the 2026 Convertible Notes without the embedded conversion option. The difference between the entire instrument with the embedded conversion option compared to the instrument without the embedded conversion option is the fair value of the derivative, recorded as the Derivative Liability. Refer to Note 11 for details regarding the determination of fair value. A roll forward of the derivative liability is as follows: ​ ​ ​ ​ ​ ​ ​ As of Balance at December 31, 2020 ​ $ 98,313 Change in fair value ​ ​ ( 78,121 ) Balance at December 31, 2021 ​ $ 20,192 Change in fair value ​ ​ ( 13,841 ) Balance at December 31, 2022 ​ $ 6,351 ​ Warrants ​ In April 2014, the Company entered into a credit facility with Silicon Valley Bank and MidCap Financial SBIC, LP, and it issued the lenders warrants to purchase 100,000 shares of its Series D-1 redeemable convertible preferred stock with an exercise price of $ 3.00 per share. Upon the closing of the Company’s IPO in July 2014, the preferred stock warrants became warrants to purchase an aggregate of 37,878 shares of its common stock with an exercise price of $ 7.92 per share, with Silicon Valley Bank and MidCap Financial SBIC, LP., each holding warrants of 18,939 shares of common stock. The Company had warrants for the purchase of 18,939 shares of common stock outstanding with MidCap Financial SBIC, LP at December 31, 2020 at a weighted average exercise price of $ 7.92 per share and an expiration date of April 17, 2021. On January 29, 2021, holders of warrants to purchase 18,939 shares of common stock at an exercise price of $ 7.92 exercised their right to purchase their warrants. The exercise price of the warrants was paid through a net F-24 Table of Contents share settlement mechanism and as a result the Company issued 11,737 shares of common stock to satisfy the exercise of all the warrants. There are no warrants outstanding as of December 31, 2022 and 2021, respectively. 11. Risks and Fair Value ​ Concentration of Credit Risk and of Significant Suppliers and Customers ​ Financial instruments that potentially expose the Company to concentrations of credit risk consist primarily of cash and cash equivalents and accounts receivable. The Company has all cash and cash equivalents balances at one accredited financial institution, in amounts that exceed federally insured limits. The Company does not believe that it is subject to unusual credit risk beyond the normal credit risk associated with commercial banking relationships. ​ ​ The Company is dependent on a small number of third-party manufacturers to supply products for research and development activities in its preclinical and clinical programs and for sales of its products. The Company’s development programs as well as revenue from future sales of its product sales could be adversely affected by a significant interruption in the supply of any of the components of these products. ​ For the year ended December 31, 2022, three specialty distributor customers accounted for 44 %, 25 % and 17 % of the Company’s total revenue, and at December 31, 2022, three specialty distributor customers accounted for 52 %, 24 % and 15 % of the Company’s total accounts receivable. No other customer accounted for more than 10% of total revenue for the year ended December 31, 2022, or accounts receivable at December 31, 2022. ​ For the year ended December 31, 2021, three specialty distributor customers accounted for 42 %, 26 % and 17 % of the Company’s total revenue, and at December 31, 2021 and three specialty distributor customers accounted for 42 %, 26 % and 21 % of the Company’s total accounts receivable. No other customer accounted for more than 10% of total revenue for the year ended December 31, 2022, or accounts receivable at December 31, 2021. ​ For the year ended December 31, 2020, three specialty distributor customers accounted for 42 %, 29 % and 12 % of the Company’s total revenue. ​ Fair Value of Financial Assets and Liabilities ​ The following tables present information about the Company’s financial assets and liabilities that are measured at fair value on a recurring basis as of December 31, 2022 and 2021 and indicate the level of the fair value hierarchy utilized to determine such fair value: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair Value Measurements as of ​ ​ December 31, 2022 Using: ​ Level 1 Level 2 Level 3 Total Assets: ​ ​ ​ ​ Cash equivalents: ​ ​ ​ ​ Money market funds ​ $ 30,188 ​ $ — ​ $ — ​ $ 30,188 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Liability: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Derivative liability (Note 10) ​ $ — ​ $ — ​ $ 6,351 ​ $ 6,351 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair Value Measurements as of ​ ​ December 31, 2021 Using: ​ Level 1 Level 2 Level 3 Total Assets: ​ ​ ​ ​ Cash equivalents: ​ ​ ​ ​ Money market funds ​ $ 62,392 ​ $ — ​ $ — ​ $ 62,392 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Liability: ​ ​ ​ ​ Derivative liability (Note 10) ​ $ — ​ $ — ​ $ 20,192 ​ $ 20,192 ​ F-25 Table of Contents During the year ended December 31, 2022 and 2021, there were no transfers between Level 1 and 2. ​ The carrying value of accounts receivable, prepaid expenses and other current assets, accounts payable and accrued expenses approximate their fair value due to the short-term nature of these assets and liabilities. The carrying value of the Company’s variable interest rate notes payable are recorded at amortized costs, which approximates fair value due to the variable interest rate. ​ At December 31, 2022, the 2026 Convertible Notes, net of the Derivative Liability, were carried at amortized cost totaling $ 37,505 , comprised of the $ 28,749 non-current liability (Note 9) and $ 8,756 accrued interest (Note 8). At December 31, 2021, the 2026 Convertible Notes, net of the Derivative Liability, were carried at amortized cost totaling $ 32,910 , comprised of the $ 26,435 non-current liability (Note 9) and $ 6,475 accrued interest (Note 8). The estimated fair value of the 2026 Convertible Notes, without the Derivative Liability, was $ 33,177 and $ 32,598 at December 31, 2022 and 2021, respectively. ​ The fair value of the 2026 Convertible Notes with and without the conversion option is estimated using a binomial lattice approach. The use of this approach requires the use of Level 3 unobservable inputs. The main input when determining the fair value of the 2026 Convertible Notes is the bond yield that pertains to the host instrument without the conversion option. The significant assumption used in determining the bond yield is the market yield movements of a comparable instrument issued as of the valuation date, which is assessed and updated each period. The main input when determining the fair value for disclosure purposes is the bond yield which is updated each period to reflect the yield of a comparable instrument issued as of the valuation date. The estimated fair value presented is not necessarily indicative of an amount that could be realized in a current market exchange. The use of alternative inputs and estimation methodologies could have a material effect on these estimates of fair value. ​ The main inputs to valuing the 2026 Convertible Notes with the conversion option are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ As of ​ ​ ​ December 31, ​ December 31, ​ ​ ​ 2022 ​ 2021 ​ Company's stock price ​ $ 2.81 ​ $ 6.97 ​ Volatility ​ ​ 93.8 % ​ 82.6 % Bond yield ​ ​ 16.2 % ​ 12.6 % ​ The bond yield was derived by making the fair value of the 2026 Convertible Notes equal to the face value on the issuance date. Fair value measurements are highly sensitive to changes in these inputs and significant changes in these inputs would result in a significantly higher or lower fair value. 12. Equity ​ Preferred Stock ​ The Amended and Restated Certificate of Incorporation authorized 5,000,000 shares of preferred stock, $ 0.0001 par value, all of which is undesignated and none of which are issued or outstanding at December 31, 2022 and 2021. Common Stock ​ The Amended and Restated Certificate of Incorporation authorized 100,000,000 shares of the Company’s common stock. Each share of common stock entitles the holder to one vote on all matters submitted to a vote of the Company’s stockholders. In June 2021, the Company adopted an amended and restated certificate of incorporation increasing the number of its authorized shares of its common stock to 200,000,000 shares. ​ On April 5, 2019, the Company entered into an Open Market Sales Agreement (the “2019 Sales Agreement”) with Jefferies, under which the Company may offer and sell its common stock having aggregate proceeds of up to $ 50,000 from time-to-time through Jefferies, acting as agent. In the twelve months ended December 31, 2020, the Company sold 2,984,381 shares of common stock under the 2019 Sales Agreement, resulting in net proceeds of approximately F-26 Table of Contents $ 14,359 , respectively, after commissions and expenses. From inception through March 1, 2021, the Company sold an aggregate of 10,321,840 shares of common stock under the 2019 Sales Agreement, resulting in net proceeds of approximately $ 46,985 after commissions and expenses. On August 9, 2021, the Company and Jefferies mutually terminated the 2019 Sales Agreement and entered into another Open Market Sale Agreement (the “2021 Sales Agreement”) under which the Company may offer and sell shares of common stock of the Company having an aggregate offering price of up to $ 100,000 from time to time through Jefferies, acting as agent. As of March 3, 2023, the Company has no t sold any shares of common stock under the 2021 Sales Agreement. ​ On December 14, 2020, the Company entered into an underwriting agreement with Jefferies LLC (“Jefferies”) and Piper Sandler & Co. (collectively with Jefferies, “the Underwriters”) in connection with an underwritten public offering of 3,725,000 shares of the Company’s common stock. Under the terms of this underwriting agreement, the Company also granted the Underwriters an option to purchase up to an additional 558,750 shares of common stock at the public offering price, less the underwriting discounts and commissions. The Underwriters subsequently exercised this option to purchase such option shares in full. The public offering price of the shares in this offering was $ 21.50 per share, and the Underwriters purchased all of the shares from the Company at a price of $ 20.21 per share. After deducting underwriting discounts and commissions and offering expenses, the Company received net proceeds from the offering of $ 86,390 . ​ On October 13, 2020, the Company entered into an underwriting agreement with the Underwriters, in connection with an underwritten public offering of 7,180,000 shares of the Company’s common stock. Under the terms of this underwriting agreement, the Company also granted the Underwriters an option to purchase up to an additional 1,077,000 shares of common stock at the public offering price, less the underwriting discounts and commissions. The Underwriters subsequently exercised this option to purchase such option shares in full. The public offering price of the shares in this offering was $ 9.75 per share, and the Underwriters purchased all of the shares from the Company at a price of $ 9.17 per share. After deducting underwriting discounts and commissions and offering expenses, the Company received net proceeds from the offering of $ 75,406 . ​ In May 2020, the Company entered into an underwriting agreement with the Underwriters, in connection with an underwritten public offering of 8,181,819 shares of the Company’s common stock. Under the terms of this underwriting agreement, the Company also granted the Underwriters an option to purchase up to an additional 1,227,272 shares of common stock at the public offering price, less the underwriting discounts and commissions. The Underwriters subsequently exercised this option to purchase such option shares in full. The public offering price of the shares in this offering was $ 5.50 per share, and the Underwriters purchased all of the shares from the Company at a price of $ 5.17 per share. After deducting underwriting discounts and commissions and offering expenses, the Company received net proceeds from the offering of $ 48,327 . ​ As of December 31, 2022, the Company had reserved 21,653,015 shares of common stock for the exercise of outstanding stock options, the vesting of restricted stock units, and the number of shares remaining available for grant under the Company’s 2021 Stock Incentive Plan, 2014 Stock Incentive Plan, the 2019 Inducement Stock Incentive Plan, and the 2014 Employee Stock Purchase Plan (Note 13). ​ 13. Stock-Based Awards ​ For the years ended December 31, 2022 and 2021, the Company had four stock-based compensation plans under which it was able to grant stock-based awards, the 2014 Stock Incentive Plan (the “2014 Plan”), the 2021 Stock Incentive Plan (the “2021 Plan”), the 2019 Inducement Plan, and the 2014 Employee Stock Purchase Plan (the “ESPP”), collectively the “Stock Plans”. Certain inducement awards made prior to inception of the 2019 Inducement Plan were issued outside of the Stock Plans. The purpose of the Stock Plans is to provide incentives to employees, directors, and nonemployee consultants. The 2014 Plan and the 2021 Plan provide for the grant of incentive stock options, non-statutory stock options, restricted stock awards, restricted stock units (“RSUs”), stock appreciation rights and other stock-based awards. As of December 31, 2022 and 2021, respectively, the Company had an immaterial number of vested stock awards outstanding that were granted under the Company’s 2006 Stock Incentive Plan (the “2006 Plan”). Effective as of the adoption of the 2014 Plan by the Company’s stockholders in 2014, no new awards have been granted under the 2006 Plan. As of December 31, 2022, all then outstanding awards under the 2006 Plan remained in effect and continued to be governed by the terms of the 2006 Plan. ​ 2014 Plan - The number of shares initially reserved for issuance under the 2014 Plan was 1,336,907 shares of common stock. Between 2014 and 2021, the number of shares reserved for issuance under the 2014 Plan increased to F-27 Table of Contents 8,622,647 as of January 1, 2021. On June 18, 2021, the Company’s stockholders approved the adoption of the 2021 Plan previously approved by the board of directors. Effective as of the adoption of the 2021 Plan by the Company’s stockholders, no new awards have been granted under the 2014 Plan. However, as of December 31, 2022, all then-outstanding awards under the 2014 Plan remained in effect and continued to be governed by the terms of the 2014 Plan. 2021 Plan - The number of shares initially reserved for issuance under the 2021 Plan was 6,000,000 shares of common stock; plus 456,334 shares remaining available for grant under the 2014 Plan as of immediately prior to the effective date of the 2021 Plan and 9,766,336 shares subject to awards granted under the 2014 Plan or the 2006 Plan, which awards expire, terminate or are otherwise surrendered, canceled, forfeited or repurchased by the Company at their original issuance price pursuant to a contractual repurchase right (subject to certain limitations). On June 16, 2022, the Company’s stockholders approved an increase of the number of shares of common stock that is reserved for issuance by 3,600,000 . As of December 31, 2022, 5,863,174 shares remained available for issuance under the 2021 Plan. 2019 Inducement Plan - The 2019 Inducement Plan provides for the following types of awards, each of which is referred to as an “Award”: non-statutory stock options, stock appreciation rights, restricted stock, restricted stock units and other stock-based awards. Awards under the 2019 Inducement Plan may only be granted to persons who (a) were not previously an employee or director of the Company or (b) are commencing employment with the Company following a bona fide period of non-employment, in either case as an inducement material to the individual’s entering into employment with the Company and in accordance with the requirements of Nasdaq Stock Market Rule 5635(c)(4). For the avoidance of doubt, neither consultants nor advisors shall be eligible to participate in the 2019 Inducement Plan. Each person who is granted an Award under the 2019 Inducement Plan is deemed a “Participant”. On December 10, 2020, the board of directors of the Company amended the 2019 Inducement Plan to increase the aggregate number of shares issuable by 554,000 shares of common stock to 1,054,000 . As of December 31, 2022, 545,375 shares remained available for issuance under the 2019 Inducement Plan. ​ ESPP – The number of shares initially reserved for issuance under the ESPP was 207,402 shares of common stock. The number of shares of common stock that may be issued under the ESPP will automatically increase on the first day of each fiscal year, commencing on January 1, 2015 and ending on December 31, 2024, in an amount equal to the least of 207,402 shares of the Company’s common stock, 0.5 % of the number of shares of the Company’s common stock outstanding on the first day of the applicable fiscal year, and an amount determined by the Company’s board of directors. On January 1, 2022, the number of shares available for issuance under the ESPP increased by 207,402 . As of December 31, 2022, 482,073 shares of common stock remained available for issuance. Stock options granted pursuant to the Stock Plans, excluding awards under the ESPP, are granted at exercise prices not to be less than the fair value of common shares as of the date of grant. They generally require a service period of 4 years and generally vest monthly, or 1/4 on the first anniversary of the grant date, with the remainder vesting monthly over the remaining three years. Stock Options granted under the 2019 Inducement Plan may in addition be subject to performance-based vesting. The maximum contractual term of Stock Options granted under the Stock Plans is generally 10 years . RSUs granted pursuant to the Stock Plans generally require a service period of 3 years and generally vest 1/3 on each anniversary of the grant date. Valuation of Awards ​ The fair value of each stock option grant is estimated on the date of grant using the Black-Scholes option-pricing model. The expected life of the options was calculated using the simplified method. The simplified method defines the life as the average of the contractual term of the options and the weighted-average vesting period for all option tranches. The Company utilizes the simplified method because the Company does not have sufficient historical exercise data over the life of awards to provide a reasonable basis upon which to estimate expected term. The expected term of stock options granted to nonemployees is equal to the contractual term of the option award. The risk-free interest rate is determined by reference to the U.S. Treasury yield curve in effect at the time of grant of the award for time periods approximately equal to the expected term of the award. Expected dividend yield is based on the fact that the Company has never paid cash dividends and does not expect to pay any cash dividends in the foreseeable future. The Company uses its historical volatility to estimate expected volatility. ​ F-28 Table of Contents The assumptions that the Company used to determine the fair value of the stock options granted to employees and directors are as follows, presented on a weighted average basis: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended ​ ​ December 31, ​ 2022 2021 2020 Risk-free interest rate 2.10 % 0.80 % 1.12 % Expected term (in years) 6 6 6 ​ Expected volatility 81.14 % 87.65 % 86.00 % Expected dividend yield — % — % — % ​ For RSUs, the grant date fair value is the closing price of the Company’s stock on the grant date. ​ Stock Options ​ The following table summarizes the Company’s stock option activity: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted ​ ​ ​ ​ ​ ​ ​ Weighted ​ Average ​ ​ ​ ​ ​ ​ ​ Average ​ Remaining ​ Aggregate ​ ​ Shares Issuable ​ Exercise ​ Contractual ​ Intrinsic ​ Under Options Price Term Value ​ ​ ​ ​ ​ ​ ​ (In years) ​ ​ ​ Outstanding as of December 31, 2021 10,934,828 ​ $ 9.60 7.1 ​ $ 13,283 Granted 3,834,053 ​ 4.95 ​ ​ ​ ​ ​ Exercised ( 137,502 ) ​ 3.69 ​ ​ ​ ​ ​ Cancelled/forfeited ( 961,668 ) ​ 8.45 ​ ​ ​ ​ ​ Outstanding as of December 31, 2022 13,669,711 ​ $ 8.45 ​ 7.0 ​ $ 7 Options vested and expected to vest as of December 31, 2022 12,179,808 ​ $ 8.14 ​ 6.8 ​ $ 7 Options exercisable as of December 31, 2022 8,565,338 ​ $ 8.54 ​ 6.0 ​ $ 7 ​ The aggregate intrinsic value of stock options is calculated as the difference between the exercise price of the stock options and the fair value of the Company’s common stock for those stock options that had exercise prices lower than the fair value of the Company’s common stock. The aggregate intrinsic value of stock options exercised was $ 186 , $ 6,779 and $ 4,307 during the years ended December 31, 2022, 2021 and 2020, respectively. ​ The weighted average grant date fair value of stock options granted to employees and directors during the years ended December 31, 2022, 2021 and 2020 was $ 4.95 , $ 12.48 and $ 5.93 per share, respectively. ​ As of December 31, 2022, there were 563,880 outstanding unvested service-based stock options held by nonemployees. ​ RSUs ​ The following table summarizes the Company’s activity of unvested RSUs: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted ​ ​ ​ ​ average ​ ​ ​ ​ grant date ​ RSU's fair value ​ ​ ​ ​ ​ ​ Unvested balance at December 31, 2021 — ​ $ — ​ Granted 1,173,898 ​ 5.04 ​ Cancelled/forfeited ( 81,216 ) ​ 5.14 ​ Unvested balance at December 31, 2022 1,092,682 ​ $ 5.03 ​ ​ ​ ​ ​ ​ ​ ​ ​ F-29 Table of Contents Each RSU is equivalent to one share of common stock upon vesting. Each RSU award vests on an annual basis over a three-year period. Holders of RSUs are not entitled to vote on any matters and are not entitled to dividends. The Company has determined the fair value of each RSU based on the closing price of the Company’s common stock on the date of grant and recognizes the compensation expense using the straight-line method over the service period, which coincides with the vesting period. ​ Stock-based Compensation ​ The Company recorded stock-based compensation expense in the following expense categories of its statements of operations and comprehensive loss: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 2022 2021 2020 Research and development ​ $ 4,166 ​ $ 3,750 ​ $ 1,514 ​ Selling and marketing ​ 4,684 ​ 4,014 ​ 1,719 ​ General and administrative ​ 8,114 ​ 7,214 ​ 4,298 ​ ​ ​ $ 16,964 ​ $ 14,978 ​ $ 7,531 ​ ​ As of December 31, 2022, the Company had an aggregate of $ 20,620 of unrecognized stock-based compensation cost, which is expected to be recognized over a weighted average period of 2.4 years. ​ 14. Employee Benefits ​ The Company established a defined contribution savings plan under Section 401(k) of the Internal Revenue Code (the “401(k) Plan”). The 401(k) Plan covers substantially all employees who meet minimum age and service requirements and allows participants to defer a portion of their annual compensation on a pre-tax basis. Company contributions to the plan may be made at the discretion of the board of directors. For the years ended December 31, 2022, 2021 and 2020, the Company has made contributions of $ 593 , $ 493 , and $ 0 , respectively, to the 401(k) Plan. ​ 15. Income Taxes ​ During the years ended December 31, 2022, 2021 and 2020, the Company recorded no income tax benefits for the net operating losses incurred or the research and development tax credits generated in each year, due to its uncertainty of realizing a benefit from those items. ​ A reconciliation of the U.S. federal statutory income tax rate to the Company’s effective income tax rate is as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ 2022 2021 2020 Federal statutory income tax rate 21.0 % 21.0 % 21.0 % Research and development tax credits 5.4 ​ 35.9 1.0 ​ State taxes, net of federal benefit 2.6 ​ 19.3 1.0 ​ Stock-based compensation ( 2.1 ) ​ ( 7.8 ) — ​ Derivative liability ​ 2.7 ​ 244.7 ​ ( 11.5 ) ​ Change in tax rate ​ 1.4 ​ ( 8.4 ) ​ — ​ Other ( 0.1 ) ​ ( 3.8 ) — ​ Change in the valuation allowance ( 30.9 ) ​ ( 300.9 ) ( 11.5 ) ​ Effective income tax rate — % — % — % ​ Changes in the valuation of the derivative liability do not provide a future tax benefit. To the extent the deferred tax asset related to the derivative liability exceeds the deferred tax liability related to the 2026 Convertible Notes, the excess is recorded as a permanent item. F-30 Table of Contents Net deferred tax assets consisted of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ 2022 2021 Deferred tax assets: ​ ​ ​ ​ ​ ​ Net operating loss carryforwards ​ $ 113,801 ​ $ 106,265 Tax credit carryforwards ​ 19,653 ​ 15,853 Capitalized start-up costs ​ 255 ​ 373 Capitalized research and development expenses, net - Sec. 59(e) : ​ 5,773 ​ 7,828 Capitalized research and development expenses, net Sec. 174 ​ ​ 10,046 ​ ​ — Operating lease liabilities ​ ​ 2,422 ​ ​ 1,705 Derivative liability ​ ​ 1,497 ​ ​ 2,499 Accrued expenses and other ​ 15,057 ​ 11,712 Total deferred tax assets ​ 168,504 ​ 146,235 Valuation allowance ​ ( 164,546 ) ​ ( 142,637 ) Net deferred tax assets ​ ​ 3,958 ​ ​ 3,598 ​ ​ ​ ​ ​ ​ ​ Deferred tax liabilities: ​ ​ ​ ​ ​ ​ Operating lease right of use assets ​ ​ ( 1,895 ) ​ ​ ( 1,099 ) 2026 Convertible Notes ​ ​ ( 2,063 ) ​ ​ ( 2,499 ) Total deferred tax liabilities ​ ​ ( 3,958 ) ​ ​ ( 3,598 ) Net deferred tax assets ​ $ 0 ​ $ — ​ Changes in the valuation allowance for deferred tax assets during the years ended December 31, 2022, 2021 and 2020 related primarily to the increase in net operating loss carryforwards, amortization of capitalized research and development expenses, and increase in research and development tax credit carryforwards were as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ 2022 2021 2020 Valuation allowance as of beginning of year ​ $ 142,637 ​ $ 123,020 ​ $ 105,062 Increases recorded to income tax provision ​ 21,909 ​ 19,617 ​ 17,958 Valuation allowance as of end of year ​ $ 164,546 ​ $ 142,637 ​ $ 123,020 ​ As of December 31, 2022, the Company had net operating loss (“NOL”) carryforwards for federal and state income tax purposes of $ 453,276 and $ 322,110 , respectively. The federal and state NOLs generated for annual periods prior to January 1, 2018 begin to expire in 2026. The Company’s federal NOLs generated for the years ended since December 31, 2018, which amounted to a total of $ 327,471 , can be carried forward indefinitely. As of December 31, 2022, the Company also had available research and development tax credit carryforwards for federal and state income tax purposes of $ 13,408 and $ 7,804 , respectively, which begin to expire in 2026 and 2025, respectively. Utilization of the NOL carryforwards and research and development tax credit carryforwards may be subject to a substantial annual limitation under Section 382 of the Internal Revenue Code of 1986 (“Section 382”) due to ownership changes that have occurred previously or that could occur in the future. These ownership changes may limit the amount of carryforwards that can be utilized annually to offset future taxable income. In general, an ownership change, as defined by Section 382, results from transactions increasing the ownership of certain shareholders or public groups in the stock of a corporation by more than 50% over a three-year period. The Company has not conducted a study to assess whether a change of control has occurred or whether there have been multiple changes of control since inception due to the significant complexity and cost associated with such a study. If the Company has experienced a change of control, as defined by Section 382, at any time since inception, utilization of the NOL carryforwards or research and development tax credit carryforwards would be subject to an annual limitation under Section 382, which is determined by first multiplying the value of the Company’s stock at the time of the ownership change by the applicable long-term tax-exempt rate, and then could be subject to additional adjustments, as required. Any limitation may result in expiration of a portion of the NOL carryforwards or research and development tax credit carryforwards before utilization. Further, until a study is completed and any limitation is known, no amounts are being presented as an uncertain tax position. ​ The Company has evaluated the positive and negative evidence bearing upon its ability to realize the deferred tax assets. Management considered the Company’s cumulative net losses and concluded that it is more likely than not that F-31 Table of Contents the Company would not realize the benefits of the deferred tax assets. Accordingly, a full valuation allowance was established against the net deferred tax assets as of December 31, 2022, 2021 and 2020. ​ The Company has no t recorded any amounts for unrecognized tax benefits as of December 31, 2022, 2021 or 2020. ​ The Company files tax returns as prescribed by the tax laws of the jurisdictions in which it operates. In the normal course of business, the Company is subject to examination by federal and state jurisdictions, where applicable. There are currently no pending income tax examinations. The Company’s tax years are still open under statute from the Company’s fiscal year 2019 to the present. Earlier years may be examined to the extent that tax credit or net operating loss carryforwards are used in future periods. ​ 16. Net Loss Per Share ​ Basic and diluted net loss per share attributable to common stockholders was calculated as follows for the years ended December 31, 2022, 2021 and 2020: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 2022 2021 2020 Numerator: ​ ​ ​ Net loss attributable to common stockholders ​ $ ( 71,038 ) ​ $ ( 6,553 ) ​ $ ( 155,636 ) Denominator: ​ ​ ​ Weighted average common shares outstanding, basic ​ 76,875,035 ​ 76,392,870 ​ 60,752,225 Net loss per share - basic ​ $ ( 0.92 ) ​ $ ( 0.09 ) ​ $ ( 2.56 ) ​ For the year ended December 31, 2020, there is no dilutive impact. Therefore, diluted net loss per share is the same as basic net loss per share. Basic and diluted net loss per share was calculated as follows for the years ended December 31, 2022 and 2021: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ ​ 2022 ​ 2021 Net loss attributable to common stockholders, basic ​ ​ $ ( 71,038 ) ​ $ ( 6,553 ) Interest expense on 2026 Convertible Notes ​ ​ 4,596 ​ 4,409 Change in fair value of derivative liability ​ ​ ​ ( 13,841 ) ​ ​ ( 78,121 ) Net loss attributable to common stockholders, diluted ​ ​ $ ( 80,283 ) ​ $ ( 80,265 ) ​ ​ ​ ​ ​ ​ ​ ​ Weighted average common shares outstanding, basic ​ ​ ​ 76,875,035 ​ ​ 76,392,870 Dilutive options (treasury stock method) ​ ​ ​ — ​ ​ — Shares issuable upon conversion of 2026 Convertible Notes, as if converted ​ ​ ​ 5,769,232 ​ ​ 5,769,232 Weighted average common shares outstanding, diluted ​ ​ 82,644,267 ​ 82,162,102 ​ ​ ​ ​ ​ ​ ​ ​ Net loss per share attributable to common stockholders, diluted ​ ​ $ ( 0.97 ) ​ $ ( 0.98 ) ​ The Company excluded the following common stock equivalents, outstanding as of December 31, 2022, 2021 and 2020 from the computation of diluted net loss per share attributable to common stockholders for the years ended December 31, 2022, 2021 and 2020 because they had an anti-dilutive impact due to the net loss incurred for the periods. F-32 Table of Contents The Company also excluded the shares issuable upon conversion of the 2026 Convertible Notes from the computation of diluted net loss per share for the year ended December 31, 2020 because they had an anti-dilutive impact. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ ​ 2022 2021 2020 Options to purchase common stock 13,669,711 10,934,828 9,114,735 ​ Restricted stock units ​ 1,092,682 ​ — ​ — ​ Shares issuable upon conversion of 2026 Convertible Notes, if converted — — 5,769,232 ​ Warrants for the purchase of common stock — — 18,939 ​ ​ 14,762,393 10,934,828 14,902,906 ​ ​ ​ 17. Commitments and Contingencies ​ Indemnification Agreements In the ordinary course of business, the Company enters into agreements that may include indemnification provisions. Pursuant to such agreements, the Company may indemnify, hold harmless and defend indemnified parties for losses suffered or incurred by the indemnified party. Some of the provisions will limit losses to those arising from third-party actions. In some cases, the indemnification will continue after the termination of the agreement. The maximum potential amount of future payments the Company could be required to make under these provisions is not determinable. To date, the Company has not incurred any material costs as a result of such indemnifications. 18. Related Party Transactions ​ In November 2020, the Company engaged Specialty Pharma Consulting, LLC (“Specialty Pharma”), an entity affiliated with Kevin Coughenour, to provide services for quality engineering and validation activities in the ordinary course of business. Mr. Coughenour is married to the Company’s former Chief Operating Officer Patricia Kitchen. On April 26, 2021, the Company and Specialty Pharma terminated their relationship. The Company incurred fees for quality engineering and validation activities rendered by Specialty Pharma of $ 0 , $ 155 and $ 47 for the years ended December 31, 2022, 2021 and 2020, respectively. As of December 31, 2022 and 2021, there were no liabilities recorded with regard to Specialty Pharma. ​ The Company has engaged Wilmer Cutler Pickering Hale and Dorr LLP (“WilmerHale”) to provide certain legal services to the Company. The Company's Chief Business Officer’s sister is a managing partner at WilmerHale, who has not participated in providing legal services to the Company. The Company incurred fees for legal services rendered by WilmerHale of approximately $ 959 , $ 1,396 and $ 1,772 for the years ended December 31, 2022, 2021 and 2020, respectively. As of December 31, 2022 and 2021, there was $ 0 and $ 119 recorded in accounts payable for WilmerHale. As of December 31, 2022 and 2021, there was $ 24 and $ 68 recorded in accrued expenses for WilmerHale. ​ ​ 19 . Subsequent Events ​ The number of shares of common stock that may be issued under the ESPP will automatically increase on the first day of each fiscal year, commencing on January 1, 2015 and ending on December 31, 2024, in an amount equal to the least of 207,402 shares of the Company’s common stock, 0.5 % of the number of shares of the Company’s common stock outstanding on the first day of the applicable fiscal year, and an amount determined by the Company’s board of directors. On January 1, 2023, the number of shares available for issuance under the ESPP increased by 207,402 . ​ ​ ​ ​ ​ ​ ​ F-33