Prime Medicine, Inc. 10-K

Item 9A. Controls and Procedures Evaluation of Disclosure Controls and Procedures Our management, with the participation of our Chief Executive Officer (who serves as both our principal executive officer and our principal financial officer), evaluated, as of the end of the period covered by this Annual Report on Form 10-K, the effectiveness of our disclosure controls and procedures as defined in Rules 13a-15(e) and 15d-15(e) under the Exchange Act. The term “disclosure controls and procedures,” as defined in Rules 13a-15(e) and 15d-15(e) under 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, or persons performing similar functions, as appropriate to allow timely decisions regarding required disclosure. Management 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, 2025, our Chief Executive Officer concluded that our disclosure controls and procedures as of such date are effective at the reasonable assurance level. Management’s Annual Report on Internal Controls Over Financial Reporting Our management is responsible for establishing and maintaining adequate internal control over our financial reporting. Internal control over financial reporting is defined in Rules 13a-15(f) and 15d-15(f) promulgated under the Exchange Act as a process designed by, or under the supervision of, our principal executive and principal financial officers and effected by our board of directors, management, and other personnel to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with United States GAAP. Our internal control over financial reporting includes those policies and procedures that: • pertain to the maintenance of records that, in reasonable detail, accurately, and fairly reflect our transactions and dispositions of our assets; • provide reasonable assurance that transactions are recorded as necessary to permit preparation of financial statements in accordance with United States GAAP, and that our receipts and expenditures are being made only in accordance with authorizations of our management and directors; and • provide reasonable assurance regarding prevention or timely detection of unauthorized acquisition, use or disposition of our assets that could have a material effect on our financial statements. Because of its inherent limitations, internal control over financial reporting may not prevent or detect misstatements. 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 assessed the effectiveness of our internal control over financial reporting as of December 31, 2025. In making this assessment, management used the criteria set forth by the Committee of Sponsoring Organizations of the Treadway Commission in its 2013 Internal Control – Integrated Framework. Based on our assessment, our management has concluded that, as of December 31, 2025, our internal control over financial reporting is effective based on those criteria. 125 Attestation Report of the Registered Public Accounting Firm This Annual Report does not include an attestation report of out registered public accounting firm regarding our internal control over financial reporting due to an exemption provided by the JOBS Act for “emerging growth companies.” Changes in Internal Control over Financial Reporting We continuously seek to improve the efficiency and effectiveness of our internal controls, which may result in changes to our systems and refinements to our processes. However, there were no changes in our internal control over financial reporting (as defined in Rules 13a-15(f) and 15d-15(f) under the Exchange Act) during the fiscal quarter ended December 31, 2025 that have materially affected, or are reasonably likely to materially affect, our internal control over financial reporting. Item 9B. Other Information (a) None. (b) From time to time, our officers (as defined in Rule 16a–1(f)) and directors may enter into Rule 10b5-1 or non-Rule 10b5-1 trading arrangements (as each such term is defined in Item 408 of Regulation S-K). During the three months ended December 31, 2025, none of our directors or officers adopted , modified or terminated a plan or other arrangement intended to satisfy the affirmative defense conditions of Rule 10b5-1(c) or any non-Rule 10b5-1 trading arrangements (as defined in Item 408(c) of Regulation S-K). Item 9C. Disclosure Regarding Foreign Jurisdictions that Prevent Inspections Not applicable. 126 PART III Item 10. Directors, Executive Officers and Corporate Governance Executive officers and directors Our executive officers and directors, and their ages and positions as of March 3, 2026, are as set forth below. Name Age Position Allan Reine, M.D. 51 Chief Executive Officer and Director (Class II) Ann Lee, Ph.D. 64 Chief Technical Officer Thomas Cahill, M.D., Ph.D. 39 Director (Class III) Wendy Chung, M.D., Ph.D. 57 Director (Class II) Kaye Foster 66 Director (Class II) Michael Kelly 69 Director (Class I) Jeffrey Marrazzo 47 Director (Class II) Robert Nelsen 62 Director (Class III) David Schenkein, M.D. 68 Director (Class I) Executive Officers Allan Reine, M.D. has served as our Chief Executive Officer and a member of our board of directors since May 2025. He previously served as our former Chief Financial Officer from January 2024 to May 2025 . Prior to joining Prime, Dr. Reine served as Chief Financial Officer of Foghorn Therapeutics Inc. from September 2019 to January 2024, and as Chief Financial Officer of Pieris Pharmaceuticals, Inc. from August 2017 to September 2019. From August 2012 through August 2017, Dr. Reine was a portfolio manager at Lombard Odier Asset Management, where he ran a healthcare portfolio focused on biotechnology and pharmaceutical companies. Before joining Lombard Odier, from 2003 through August 2012, Dr. Reine served as a healthcare portfolio manager at various funds, including Citi Principal Strategies, SAC Capital, Trivium Capital and Alexandra Investment Management. Dr. Reine began his career in 2001 at CIBC World Markets where he worked in both biotechnology investment banking and biotechnology equity research. Dr. Reine received his M.D. from the University of Toronto and his B.Sc. in Statistical Sciences from the University of Western Ontario. We believe that Dr. Reine is qualified to serve on our board of directors based on his extensive experience as a senior executive in the pharmaceutical industry, his public company experience, as well as his knowledge of our company based on his role as our former Chief Financial Officer and current Chief Executive Officer. Ann L. Lee, Ph.D. has served as our Chief Technical Officer since October 2021. Prior to that, Dr. Lee served as Senior Vice President and Head of Cell Therapy Development and Operations at BMS from November 2019 to July 2021, as Executive Vice President of Cell Therapy Development and Operations at Celgene Corporation, a biopharmaceutical company, from April 2018 to November 2019 and as Executive Vice President of Technical Operations at Juno from November 2017 to April 2018. From April 2009 to November 2017, Dr. Lee served as Senior Vice President and Global Head of Pharma Technical Development at Genentech, Inc., a Roche Group subsidiary and a biotechnology company. She currently serves on the board of directors and audit and compensation committees of Coya Therapeutics, Inc. Dr. Lee received her Ph.D. in biochemical engineering from Yale University and her B.S. in chemical engineering from Cornell University. Non-employee directors Thomas Cahill, M.D., Ph.D. has served as a member of our board of directors since November 2021. Dr. Cahill is the Founder and has served as the Managing Partner of Newpath Partners, a Boston-based life science venture fund focused on therapeutic companies, since October 2018. Dr. Cahill is the founding investor and director of nChroma Bio, Inc., Exo Therapeutics, Inc., Kisbee Therapeutics, Inc., Magnet Biomedicine, Inc., Myeloid Therapeutics, Inc., or Myeloid, Convergence Bio, Inc., Autobahn Therapeutics, Inc., Leal Therapeutics, Inc. and Amplitude Therapeutics , Inc. Prior to Newpath Partners, Dr. Cahill served as an Advisor at Raptor Group Holdings, where he 127 helped further establish and lead the life science and technology investment portfolio, from September 2016 to May 2018. Dr. Cahill received both his M.D. and Ph.D. from Duke University and his M.S. from Stanford University. We believe that Dr. Cahill is qualified to serve on our board of directors based on his experience in the medical and venture capital industries. Wendy Chung, M.D., Ph.D. has served as a member of our board of directors since November 2021. Dr. Chung is an American Board of Medical Genetics certified clinical and molecular geneticist and serves as the Chair of the Department of Pediatrics at Boston Children’s Hospital, a position she has held since July 2023. Previously, she led the Precision Medicine Resource in the Irving Institute at Columbia University from February 2014 to June 2023. Dr. Chung was on the faculty at Columbia University from 2002 to June 2023, most recently as the Kennedy Family Professor of Pediatrics and Medicine at Columbia University. Prior to that, she was an Associate Professor at Columbia University. Dr. Chung has served as a member of the board of directors of Rallybio Corporation, a public biotechnology company, since August 2022. She received her B.A. in Biochemistry from Cornell University, her M.D. from Cornell University Medical College, and her Ph.D. in Genetics from The Rockefeller University. We believe that Dr. Chung is qualified to serve on our board of directors because of her extensive experience in medicine and genetics research. Kaye Foster has served as a member of our board of directors since December 2021. Ms. Foster has been a Senior Advisor at the Boston Consulting Group since August 2014 and a Venture Partner at ARCH since January 2022. Previously, she was Senior Vice President, Global Human Resources at Onyx Pharmaceuticals, Inc., an Amgen, Inc. subsidiary and a biopharmaceutical company, from October 2010 to January 2014. At Onyx, she led all aspects of human resources for U.S. and global operations. Prior to joining Onyx, Ms. Foster was Global Vice President of Human Resources and an Executive Committee member at Johnson and Johnson Corporation, a healthcare company, from May 2003 to March 2010. Before Johnson and Johnson, Ms. Foster held several senior human resources executive positions with Pfizer Inc., a pharmaceuticals company. She currently serves on the board of directors and compensation committee of National Resilience Inc.; on the board of directors and the compensation and nominating and corporate governance committees of Agios Pharmaceuticals, Inc.; and on the board of trustees and the human resources committee of Spelman College. Ms. Foster previously served on the board of directors and real estate and nominations committees of Stanford Health Care, a hospital and healthcare system, and chaired the Glide Memorial Foundation Board of Trustees. She received her B.B.A. in Business Administration from Baruch College of the City University of New York and her M.B.A. from Columbia University, Graduate School of Business. We believe Ms. Foster is qualified to serve on our board of directors because of her extensive experience as an executive in the pharmaceuticals industry, including her experience in people management, compensation planning and driving and maintaining corporate culture. Michael A. Kelly has served as a member of our board of directors since November 2021. Mr. Kelly is currently acting as Founder & President of Sentry Hill Partners, LLC, a global life sciences transformation and management consulting business founded by Mr. Kelly in January 2018. From February 2003 to December 2017, he was a senior executive of Amgen, Inc., a biotechnology company, where he most recently served as Senior Vice President, Global Business Services and Vice President & Chief Financial Officer, International Commercial Operations. He also serves on the boards of directors of: Amicus Therapeutics, Inc., a biotechnology company, which he joined in December 2020; DMC Global Inc., a composite materials and oil field products company, which he joined in July 2020; NeoGenomics Laboratories, Inc., a genetics testing company, which he joined in July 2020, and nChroma Bio, Inc., a biotechnology company, which he joined in December 2024. Mr. Kelly previously served on the boards of directors of Aprea Therapeutics, Inc., a biotechnology company, from September 2020 to May 2022, Hookipa Pharma Inc., a biopharmaceutical company, from February 2019 to April 2023, and Chroma Medicine (which merged with Nvelop Therapeutics in December 2024 to form nChroma Bio, Inc.), a biotechnology company, from February 2023 to December 2024 . Mr. Kelly has also held positions at Tanox, Inc., Biogen, Inc., and Nutrasweet Kelco Company, a division of Monsanto Life Sciences. He also serves on the Council of Advisors and was the former audit committee chairman for Direct Relief, a humanitarian aid organization focused on health outcomes and disaster relief. Mr. Kelly received his B.Sc. in Business Administration from Florida A&M University, concentrating in Finance and Industrial Relations. We believe that Mr. Kelly is qualified to serve on our board of directors because of his extensive experience in managing and growing global healthcare and biotechnology companies. 128 Jeffrey D. Marrazzo has served as a member of our board of directors since May 2023 and as Executive Chair of our board of directors since May 2025. Currently, Mr. Marrazzo chairs the board of directors of several privately-held biotechnology companies including Dispatch Biotherapeutics and nChroma Bio. Previously, Mr. Marrazzo served as co-founder and Chief Executive Officer of Spark Therapeutics, Inc. from May 2013 to April 2022 and as a member of its board of directors from May 2013 to December 2019. In addition, Mr. Marrazzo launched and was Chief Business Officer of the U.S. division of Molecular Health, Inc. from 2011 to 2013. Mr. Marrazzo was part of the founding management of Generation Health from 2009 to 2011, up to and through the acquisition of a majority of the company’s shares by CVS Caremark. From 2008 to 2009, Mr. Marrazzo served as an employee and independent consultant to the business development and finance teams at Tengion Inc. and, from 2011 to 2013, Mr. Marrazzo served as an independent consultant to the Children’s Hospital of Philadelphia, or CHOP. Previously, Mr. Marrazzo served as healthcare advisor to former Pennsylvania Governor Edward G. Rendell and as an IBM management consultant to global pharmaceutical companies. Mr. Marrazzo holds a B.S.E. and B.A. in Systems Science and Engineering and Economics from the University of Pennsylvania and a dual M.B.A./M.P.A. from The Wharton School and Harvard University. We believe that Mr. Marrazzo is qualified to serve on our board of directors because of his extensive leadership experience in the life sciences industry. Robert Nelsen has served as a member of our board of directors since September 2020. Mr. Nelsen co-founded ARCH Venture Partners, L.P., a venture capital firm focused on early-stage technology companies, in 1986 and has served as a Managing Director of ARCH Venture Partners or its affiliated entities since 1994. Mr. Nelsen currently serves on the board of directors of Sana Biotechnology, Inc. and Hua Medicine, Inc., each a public biotechnology company, and currently serves on the board of directors of a number of private companies. Mr. Nelsen previously served on the board of directors of a number of public biotechnology companies, including Vir Biotechnology, Inc., from 2017 to May 2025, Lyell Immunopharma, Inc. from 2018 to May 2025, Brii Biosciences Limited from 2019 to June 2024, Revolution Healthcare Acquisition Corp. from 2021 to April 2022, Denali Therapeutics Inc. from 2015 to June 2022, Beam from 2017 to June 2021, Karuna Therapeutics, Inc. from 2018 to June 2021, Unity Biotechnology, Inc. from 2015 to December 2020, Agios Pharmaceuticals, Inc. from 2007 to June 2017, Syros Pharmaceuticals, Inc. from 2012 to June 2018, Juno Therapeutics, Inc. (acquired by Celgene Corporation in January 2018) from 2013 to March 2018, Sienna Biopharmaceuticals, Inc. from 2015 to September 2018 and Gossamer Bio, Inc. from 2017 to December 2018 (prior to its initial public offering). Mr. Nelsen received his M.B.A. from the University of Chicago and his B.S. from the University of Puget Sound in Economics and Biology. We believe that Mr. Nelsen is qualified to serve on our board of directors because of his extensive experience as a venture capitalist, building and serving boards of many public and private emerging companies, including multiple life sciences, biotechnology and pharmaceutical companies. David Schenkein, M.D. has served as a member of our board of directors since September 2019. Dr. Schenkein currently serves as a partner in GV, the venture capital investment arm of Alphabet Inc., which he joined in February 2019. Previously, Dr. Schenkein served as President and Chief Executive Officer of Agios Pharmaceuticals, Inc. from August 2009 to February 2019. From April 2006 to July 2009, Dr. Schenkein served as a Senior Vice President of Oncology Development at Genentech Inc. Dr. Schenkein currently serves on the board of directors of Denali Therapeutics Inc. and Regeneron Pharmaceuticals, Inc. He is also on the boards of the private companies Leyden Laboratories B.V., Aera Therapeutics, Inc. and Treeline Biosciences, Inc. Previously, Dr. Schenkein served on the board of directors of Agios Pharmaceuticals, Inc. from 2009 to February 2025 and bluebird bio, Inc. from 2013 to 2021. He also currently serves as an adjunct attending physician in hematology at Tufts Medical Center. Dr. Schenkein received his M.D. from the State University of New York Upstate Medical School and his B.A. in Chemistry from Wesleyan University. We believe that Dr. Schenkein is qualified to serve on our board of directors because of his extensive background in the biotechnology industry and leadership experience as a senior executive and director of biotechnology companies. We believe that all of our current board of directors members possess the professional and personal qualifications necessary for service on our board of directors and have highlighted particularly noteworthy attributes for each board of directors member in the individual biographies above. Role of Board in Risk Oversight Process Our board of directors has an active role, as a whole and also at the committee level, in overseeing the management of our risks. Our board of directors is responsible for general oversight of risks and regular review of information 129 regarding our risks, including credit risks, liquidity risks, operational risks and cybersecurity. The audit committee is responsible for overseeing the management of risks relating to accounting matters and financial reporting. The compensation committee is responsible for overseeing the management of risks relating to our executive compensation plans and arrangements. The nominating and corporate governance committee is responsible for overseeing the management of risks associated with the independence of our board of directors and potential conflicts of interest. Although each committee is responsible for evaluating certain risks and overseeing the management of such risks, the entire board of directors is regularly informed through discussions from committee members about such risks. Our board of directors believes its administration of its risk oversight function has not negatively affected our board of director’s leadership structure. Board Committees Our board of directors has established an audit committee, a compensation committee, and a nominating and corporate governance committee, each of which operates pursuant to a charter adopted by our board of directors. We believe that the composition and functioning of all of our committees comply with the applicable requirements of Nasdaq, the Sarbanes-Oxley Act of 2002, and SEC rules and regulations that are applicable to us. We intend to comply with future requirements to the extent they become applicable to us. The full text of our audit committee charter, compensation committee charter and nominating and corporate governance committee charter are posted on the “Corporate Governance” portion of our website at https://www.primemedicine.com . We do not incorporate the information contained on, or accessible through, our corporate website into this Annual Report on Form 10-K, and you should not consider it a part of this Annual Report on Form 10-K. The following table describes which directors serve on each of our board of directors’s committees as of March 3, 2026. Name Audit Committee Compensation Committee Nominating and Corporate Governance Committee Thomas Cahill, M.D., Ph.D. Member Member Wendy Chung, M.D., Ph.D. Member Member Kaye Foster Chair Michael Kelly Chair Robert Nelsen Member David Schenkein, M.D. Member Chair Audit Committee Among other things, our audit committee’s responsibilities include: • appointing, approving the compensation of, and assessing the independence of our independent registered public accounting firm; • pre-approving auditing and permissible non-audit services, and the terms of such services, to be provided by our independent registered public accounting firm; • reviewing the overall audit plan with our independent registered public accounting firm and members of management responsible for preparing our financial statements; • reviewing and discussing with management and our independent registered public accounting firm our annual and quarterly financial statements and related disclosures as well as critical accounting policies and practices used by us; • coordinating the oversight and reviewing the adequacy of our internal control over financial reporting; • establishing policies and procedures for the receipt and retention of accounting-related complaints and concerns; 130 • recommending based upon the audit committee’s review and discussions with management and our independent registered public accounting firm whether our audited financial statements shall be included in our Annual Report on Form 10-K; • monitoring the integrity of our financial statements and our compliance with legal and regulatory requirements as they relate to our financial statements and accounting matters; • preparing the audit committee report required by SEC rules to be included in our annual proxy statement; • reviewing all related person transactions for potential conflict of interest situations and approving all such transactions; • discussing and reviewing items of enterprise risk management and considering major risk exposures, including financial, operational, privacy, security, cybersecurity, competition, legal, regulatory, hedging and accounting risk exposures; • evaluating the performance, responsibilities, budget and staffing of our internal audit function and reviewing the internal audit plan; and • reviewing quarterly earnings releases. All audit services and all permitted non-audit services to be provided to us by our independent registered public accounting firm must be approved in advance by our audit committee. The members of our audit committee are Michael Kelly, Thomas Cahill and Wendy Chung. Mr. Kelly chairs the audit committee. All members of our audit committee meet the requirements for financial literacy under the applicable rules and regulations of the SEC and the Nasdaq listing rules. Our board of directors has determined that Mr. Kelly qualifies as an “audit committee financial expert” within the meaning of applicable SEC regulations. In making this determination, our board of directors considered the nature and scope of experience that Michael Kelly has previously had with public reporting companies, including service as a principal financial officer and principal accounting officer. Our board of directors has determined that all of the members of our audit committee satisfy the relevant independence requirements for service on the audit committee set forth in the rules of the SEC and the Nasdaq listing rules. Both our independent registered public accounting firm and management periodically meet privately with our audit committee. Our audit committee charter, which has been adopted by our board of directors, is available on our website. Compensation Committee Among other things, our compensation committee’s responsibilities include: • reviewing and reassessing periodically (and making recommendations to our board of directors if advisable) our processes and procedures for the consideration and determination of director and executive officer compensation; • annually reviewing and approving the corporate goals and objectives relevant to the compensation of our Chief Executive Officer; • evaluating the performance of our Chief Executive Officer in light of such corporate goals and objectives and based on such evaluation (i) recommending to our board of directors the cash compensation of our Chief Executive Officer and (ii) recommending to our board of directors any grants and awards to our Chief Executive Officer under equity-based plans; • reviewing and approving the compensation of our other executive officers; • providing oversight of management’s decisions regarding the compensation of our other members of senior management; • overseeing and administering our incentive-based compensation and equity-based plans; • evaluating and assessing potential and current compensation consultants or advisors in accordance with the independence standards identified in the applicable Nasdaq listing rules; 131 • reviewing and approving grants and awards under incentive-based compensation plans and equity-based plans, in each case consistent with the terms of such plans; • reviewing and recommending to our board of directors our policies and procedures for the grant of equity-based awards; • administering our compensation recovery policy; • reviewing and recommending to our board of directors the compensation of our directors; • preparing our compensation committee report if and when required by SEC rules, to be included in our annual proxy statement or Annual Report on Form 10-K in accordance with the rules and regulations of the SEC, the Nasdaq Stock Market rules and any other rules and regulations applicable to us; • reviewing and discussing annually with management our “Compensation Discussion and Analysis,” if and when required, to be included in our annual proxy statement or Annual Report on Form 10-K; and • reviewing and approving the retention or termination of any consulting firm or outside advisor to assist in the evaluation of compensation matters. The members of our compensation committee are Kaye Foster, David Schenkein and Robert Nelsen. Ms. Foster chairs the compensation committee. Each member of our compensation committee is a non-employee director, as defined in Rule 16b-3 promulgated under the Exchange Act. Our compensation committee may delegate any of the responsibilities of the full committee to subcommittees and may delegate certain responsibilities of the full committee to our executive officers and other persons as may be permitted by applicable laws, rules or regulations and in accordance with the listing standards set forth by Nasdaq. Accordingly, our compensation committee has delegated authority to our Chief Executive Officer to make certain equity awards under our 2022 Stock Option and Incentive Plan, or the 2022 Plan, to our new hires and our existing employees at the senior vice president level and below who are not (and are not reasonably expected to be upon hiring) officers (as defined in Section 16 of the Exchange Act and Rule 16a-1 promulgated thereunder) in connection with promotions, market adjustments, employee recognition or retention, in each case, subject to certain limitations. Our compensation committee charter, which has been adopted by our board of directors, is available on our website. Compensation Consultant Our compensation committee has engaged Alpine Rewards, LLC, or Alpine Rewards, as its independent compensation consultant. When requested, Alpine Rewards consultants attend meetings of our compensation committee, including executive sessions in which executive compensation-related matters are discussed without the presence of our management. Alpine Rewards reports to our compensation committee and not to our management, although Alpine Rewards meets with our management for purposes of gathering information for its analyses and recommendations. Our compensation committee assessed the independence of Alpine Rewards from management, taking into consideration relevant factors, including the other services provided to our Company by Alpine Rewards, the amount of fees our Company paid to Alpine Rewards as a percentage of Alpine Rewards’ total revenue, the policies and procedures of Alpine Rewards that are designed to prevent conflicts of interest, any business or personal relationship of the individual compensation advisors employed by Alpine Rewards with any executive officer of the Company, any business or personal relationship the individual compensation advisors employed by Alpine Rewards have with any member of our compensation committee and any stock of our Company owned by Alpine Rewards or the individual compensation advisors employed by Alpine Rewards. On the basis of that assessment and taking into consideration the independence factors that are required to be considered under applicable stock exchange rules, our compensation committee determined that no relationships existed that would create a conflict of interest or that would compromise Alpine Rewards’ independence, and that Alpine Rewards is independent pursuant to the independence standards set forth in the Nasdaq listing standards promulgated pursuant to Section 10C of the Exchange Act. 132 Nominating and Corporate Governance Committee Among other things, our nominating and corporate governance committee’s responsibilities include: • developing and recommending to our board of directors criteria for our board of directors and committee membership; • establishing procedures for identifying and evaluating our board of director candidates, including nominees recommended by stockholders; • to the extent deemed appropriate, retaining third-party search firms or other advisors to identify and evaluate director nominee candidates; • reviewing the composition of our board of directors to ensure that it is composed of members containing the appropriate skills and expertise to advise us; • identifying individuals qualified to become members of our board of directors; • recommending to our board of directors the persons to be nominated for election as directors and to each of the committees of our board of directors; • developing, recommending to our board of directors and periodically assessing the adequacy of a set of corporate governance guidelines and a code of conduct and business ethics; • overseeing the evaluation of our board of directors; and • reviewing and discussing with our board of directors corporate succession plans for our Chief Executive Officer and our other key officers. The members of our nominating and corporate governance committee are David Schenkein, Wendy Chung and Thomas Cahill. Dr. Schenkein chairs our nominating and corporate governance committee. Our board of directors has determined that each member of our nominating and corporate governance committee satisfies the independence standards of the applicable rules of Nasdaq. Our nominating and corporate governance committee charter, which has been adopted by our board of directors, is available on our website. Code of Business Conduct and Ethics Our board of directors adopted a Code of Business Conduct and Ethics, which applies to all of our employees, officers (including our principal executive officer, principal financial officer, principal accounting officer or controller, or persons performing similar functions), agents and representatives, including directors and consultants. If we make any substantive future amendments to certain provisions of our Code of Business Conduct and Ethics, or grant any waivers from our Code of Business Conduct and Ethics for any officer or director, we will disclose the nature of such amendment or waiver on our website identified below or in a Current Report on Form 8-K. The full text of our Code of Business Conduct and Ethics and our Code of Ethics is posted on our website at https://www.primemedicine.com . The inclusion of our website address in this Annual Statement on Form 10-K does not include or incorporate by reference the information on our website into this Annual Report on Form 10-K, and you should not consider that information a part of this Annual Report on Form 10-K. Director Nomination Process No material changes have been made to the procedures by which our stockholders may recommend nominees to our board of directors from those that were described in our annual proxy statement filed with the SEC on April 22, 2025. Policy on Trading, Pledging and Hedging of Company Stock Certain transactions in our securities (such as purchases and sales of publicly traded put and call options, and short sales) create a heightened compliance risk or could create the appearance of misalignment between management and stockholders. In addition, securities held in a margin account or pledged as collateral may be sold without consent if the owner fails to meet a margin call or defaults on the loan, thus creating the risk that a sale may occur at a time 133 when an officer or director is aware of material, non-public information or otherwise is not permitted to trade in our securities. Our insider trading policy expressly prohibits short sales and derivative transactions of our stock and purchases or sales of puts, calls, or our other derivative securities or any derivative securities that provide the economic equivalent of ownership of any of our securities or an opportunity, direct or indirect, to profit from any change in the value of our securities or engage in any other hedging transaction with respect to our securities, at any time, by our executive officers, directors and employees. Insider Trading Policy We have adopted an Insider Trading Policy governing the purchase, sale, and/or other dispositions of our securities by directors, officers, employees and designated consultants and contractors that we believe is reasonably designed to promote compliance with insider trading laws, rules and regulations, and the Nasdaq Stock Market listing standards that are applicable to us. A copy of our Second Amended and Restated Insider Trading Policy is included as Exhibit 19.1 in this Annual Report on Form 10-K. Our Insider Trading Policy permits our officers, directors, employees and certain other persons to enter into trading plans complying with Rule 10b5-1 under the Exchange Act. Generally, under these trading plans, the individual relinquishes control over the transactions once the trading plan is put into place and can only put such plans into place while the individual is not in possession of material non-public information. Accordingly, sales under these plans may occur at any time, including possibly before, simultaneously with, or immediately after significant events involving us. A copy of our Second Amended and Restated Insider Trading Policy is filed as Exhibit 19.1 to this Annual Report on Form 10-K. In addition, with regard to trading in our own securities, it is the our policy to comply with applicable insider trading laws, rules and regulations, and any exchange listing standards when engaging in transactions in our securities. Compensation Recovery Policy In accordance with the requirements of the SEC and Nasdaq listing rules, our board of directors adopted a compensation recovery policy on September 15, 2023, effective as of October 2, 2023. The compensation recovery policy provides that in the event we are required to prepare a restatement of financial statements due to material noncompliance with any financial reporting requirement under securities laws, we will seek to recover any incentive-based compensation that was based upon the attainment of a financial reporting measure and that was received by any current or former executive officer during the three-year period preceding the date that the restatement was required if such compensation exceeds the amount that the executive officers would have received based on the restated financial statements. Policies and Practices Related to the Grant of Certain Equity Awards We have adopted an Equity Award Grant Policy that sets forth the process and timing for us to follow when we grant equity awards for shares of our common stock to our employees or advisors or consultants (other than our non-employee directors) pursuant to our equity compensation plans. All grants of equity awards must be approved in advance by our board of directors, the compensation committee or, subject to the delegation requirements in the policy, our Chief Executive Officer. The equity award granting authority delegated to our Chief Executive Officer applies to employees at the senior vice president level and below who are not (and are not reasonably expected to be upon hiring) officers (as defined in Section 16 of the Exchange Act and Rule 16a-1 promulgated thereunder) and to equity awards within the specific ranges and subject to a maximum annual aggregate amount as may be set forth in the policy, as approved by the compensation committee from time to time. Generally, equity awards are granted on the following regularly scheduled basis as set forth in the Equity Award Grant Policy: (a) equity awards granted in connection with the hiring of a new employee or the promotion of an existing employee or the engagement of a new consultant will generally be granted, if at all, regularly (either monthly or quarterly) and will be effective on the first day of the month immediately following the month in which such individual’s employment or consulting term begins or promotion occurs, as applicable; (b) equity awards granted to existing employees (other than in connection with a promotion or other special grant) will generally be 134 granted, if at all, on an annual basis and will be effective on the date such grant is approved or such future date as approved by our board of directors, compensation committee or Chief Executive Officer, as applicable; and (c) any special grants to existing employees will be made, if at all, periodically and will be effective on the date such grant is approved or such future date as approved by our board of directors, compensation committee or Chief Executive Officer, as applicable. Our board of directors, compensation committee and Chief Executive Officer do not take into account any material nonpublic information when determining the timing and terms of equity awards. We do not time our equity award grants either to take advantage of a depressed stock price, or an anticipated increase in stock price, and we have limited the amount of discretion that can be exercised in connection with the timing of equity award grants. We also do not time the release of material nonpublic information based on equity award grant dates. The following table contains information required by Item 402(x)(2) of Regulation S-K about stock options granted to the our named executive officers, or NEOs, in the last completed fiscal year during the period beginning four business days before and ending one business day after the filing of our Annual Report on Form 10-K, our Quarterly Reports on Form 10-Q, or the filing or furnishing of any of our Current Reports on Form 8-K that discloses material nonpublic information. Name Grant Date Number of Securities Underlying the Award Exercise Price of the Award ($ per share) Grant Date Fair Value of the Award ($) Percentage change in the closing market price of the securities underlying the award between the trading day ending immediately prior to the disclosure of material nonpublic information and the trading day beginning immediately following the disclosure of material nonpublic information Allan Reine, M.D. 02/27/2025 275,000 2.42 471,598 (1) 4% Ann Lee, Ph.D. 02/27/2025 275,000 2.42 471,598 (1) 4% Jeremy Duffield, M.D., Ph.D., FRCP 02/27/2025 275,000 2.42 471,598 (1) 4% Keith Gottesdiener, M.D. 02/28/2025 500,000 2.52 892,200 (1) 4% Allan Reine, M.D. 05/19/2025 2,000,000 1.34 1,911,400 (1) (16)% Allan Reine, M.D. 05/19/2025 500,000 1.34 — (1) (16)% Allan Reine, M.D. 08/01/2025 850,000 4.04 445,801 (2) 8% Ann Lee, Ph.D. 08/01/2025 180,995 4.04 197,786 (2) 8% Ann Lee, Ph.D. 08/01/2025 180,995 4.04 120,691 (2) 8% (1) Amounts reflect the aggregate grant date fair value of option awards granted during the applicable year calculated in accordance with the provisions of Financial Accounting Standards Board, or FASB, Accounting Standards Codification, or ASC, Topic 718, Compensation—Stock Compensation . Such grant date fair values do not take into account any estimated forfeitures. Refer to Note 2, Summary of Significant Accounting Policies , to our consolidated financial statements appearing elsewhere within this Annual Report on Form 10-K for assumptions underlying the valuation of equity awards. The grant date fair value of Dr. Reine’s performance-based stock options grant for 500,000 shares, based on probable achievement of the applicable performance metrics, was $0; the grant date fair value of such performance-based stock option grant, based on maximum achievement of the applicable performance metrics, was $556,800. The amounts reported in this column reflect the accounting cost for these options and do not correspond to the actual economic value that may be received by our NEOs upon the exercise of the options or any sale of the underlying shares of common stock. (2) These options were repriced on August 1, 2025 under our stockholder approved option repricing plan, which is discussed in greater detail in Note 8, Stock-based Compensation , to our consolidated financial statements appearing elsewhere within this Annual Report on Form 10-K. Amounts reflect the aggregate incremental fair value of the repriced options, calculated in accordance with the provisions of FASB ASC Topic 718. Such grant date fair values do not take into account any estimated forfeitures. Refer to Note 2, Summary of Significant 135 Accounting Policies , to our consolidated financial statements appearing elsewhere within this Annual Report on Form 10-K for assumptions underlying the valuation of equity awards. The amounts reported in this column reflect the accounting cost for these options and do not correspond to the actual economic value that may be received by our NEOs upon the exercise of the options or any sale of the underlying shares of common stock. Director Compensation The following table presents the total compensation for each person who served as a non-employee member of our board of directors during the fiscal year ended December 31, 2025. Other than as set forth in the table and described more above, we did not pay any compensation, grant any equity awards or non-equity awards to, or pay any other compensation to any of the non-employee members of our board of directors during the fiscal year ended December 31, 2025. Dr. Reine, who is our Chief Executive Officer, and Dr. Gottesdiener, who was our former Chief Executive Officer, did not receive any additional compensation for their services as directors. The compensation received by Dr. Reine and Dr. Gottesdiener, as NEOs of the Company, are presented in the “2025 Summary Compensation Table”. Name Fees Earned or Paid in Cash ($) (1) Option Awards ($) (2) All Other Compensation ($) Total ($) Thomas Cahill, M.D., Ph.D. (3) 60,000 133,924 — 193,924 Wendy Chung, M.D., Ph.D. (3) 60,000 162,079 — 222,079 Kaye Foster (3) 60,000 162,359 — 222,359 Michael Kelly (3) 65,000 162,079 — 227,079 Jeffrey Marrazzo (4) 45,000 1,199,949 95,161 1,340,110 Robert Nelsen (3) 52,500 133,924 — 186,424 David Schenkein, M.D. (3) 62,500 133,924 — 196,424 (1) Amounts represent annual cash compensation earned for services rendered as directors by non-employee members of our board of directors and the committees thereof during the fiscal year ended December 31, 2025. (2) Amounts reflect the aggregate grant date fair value of option awards granted during 2025 in accordance with our Non-employee Director Compensation Policy, described below, calculated in accordance with the provisions of FASB ASC Topic 718, Compensation—Stock Compensation . Such grant date fair values do not take into account any estimated forfeitures. The grant date fair value of Mr. Marrazzo’s performance-based stock option grant for 200,000 shares, based on probable achievement of the applicable performance metrics, was $0; the grant date fair value of such performance-based stock option grants, based on maximum achievement of the applicable performance metrics, was $223,900. In addition to grant date fair value of options granted during 2025, the amounts also include the incremental fair value of options repriced during 2025. The aggregate incremental fair value of repriced options were $83,456 for each of Dr. Cahill, Mr. Nelsen, and Dr. Schenkein; $111,611 for each of Dr. Chung and Mr. Kelly; $111,891 for Ms. Foster; and $348,821 for Mr. Marrazzo. Refer to Note 2, Summary of Significant Accounting Policies, to our consolidated financial statements appearing elsewhere within this Annual Report on Form 10-K for assumptions underlying the valuation of equity awards. The amounts reported in this column reflect the accounting cost for these options and do not correspond to the actual economic value that may be received by our directors upon the exercise of the options or any sale of the underlying shares of common stock. (3) As part of the annual board of directors member grants, Dr. Cahill, Dr. Chung, Ms. Foster, Mr. Kelly, Mr. Nelsen, and Dr. Schenkein received options to purchase 55,000 shares of our common stock. As of December 31, 2025, Dr. Cahill, Mr. Nelsen, and Dr. Schenkein each held options to purchase an aggregate of 139,062 shares of common stock, and Dr. Chung, Ms. Foster, and Mr. Kelly each held options to purchase an aggregate of 161,578 shares of common stock. (4) Upon his appointment as the Executive Chair of the our board of directors, Mr. Marrazzo received options to purchase 1,000,000 shares of our common stock. In addition, for his services as a director, as part of the annual board of directors member grants, Mr. Marrazzo received options to purchase an additional 55,000 shares of our common stock. Under his advisory services agreement with the Company, the details of which are discussed in 136 the “Item 13. Certain Relationships and Related Transactions, and Director Independence”, Mr. Marrazzo also received fees totaling $95,161 during the year ended December 31, 2025. As of December 31, 2025, Mr. Marrazzo held options to purchase an aggregate of 1,442,000 shares of common stock. Non-Employee Director Compensation Policy We adopted a non-employee director compensation policy in May 2022 designed to enable us to attract and retain, on a long-term basis, highly qualified non-employee directors, which was amended and restated on May 17, 2024. On May 16, 2025, our board of directors approved a second amended and restated non-employee director compensation policy based upon the recommendations of our compensation committee and Alpine Rewards, our independent compensation consultant. Under the second amended and restated policy, our non-employee directors are eligible to receive annual cash retainers (which are payable quarterly in arrears and prorated for partial years of service) and equity awards as set forth below: Annual Retainer for Board of Directors All non-employee members $ 45,000 Additional Retainer for Board Chair $ 30,000 Additional Retainer for Audit Committee Chair $ 20,000 Non-chair members $ 10,000 Additional Retainer for Compensation Committee Chair $ 15,000 Non-chair members $ 7,500 Additional Retainer for Nominating and Corporate Governance Committee Chair $ 10,000 Non-chair members $ 5,000 In addition, our policy provides that, upon initial election or appointment to our board of directors, each new non-employee director will be granted a one-time grant of a non-statutory stock option to purchase 110,000 shares of our common stock on the date of such director’s election or appointment to our board of directors (the “Initial Director Grant”). The Initial Director Grant will vest in substantially equal annual installments over three years, subject to the non-employee director’s continued services to the Company. On the date of each annual meeting of stockholders of the Company, each non-employee director who will continue as a non-employee director following such meeting, other than a non-employee director receiving an Initial Director Grant, will be granted an annual award of a non-statutory stock option to purchase 55,000 shares of common stock (the “Annual Director Grant”). Notwithstanding the foregoing, if a non-employee director was initially elected to our board of directors on a date other than the date of an annual meeting, then upon such initial election or appointment, the non-employee director shall receive, in lieu of an Annual Director Grant, a grant that is pro-rated on a monthly basis for time served as a non-employee director between the date of the non-employee director’s initial election or appointment and the date of the next annual meeting. The Annual Director Grant (including any pro-rated amount) will vest in full on the earlier of the one-year anniversary of the grant date or on the date of our next annual meeting of stockholders, subject to the non-employee director’s continued services to the Company. Such awards are subject to fully accelerated vesting upon the sale of the Company. All vested options remain exercisable for twelve months if a non-employee director resigns from the board of directors or otherwise ceases to serve as a director. The aggregate amount of compensation, including both equity compensation and cash compensation, paid to any non-employee director for service as a non-employee director in a calendar year period will not exceed $1,600,000 in the first calendar year such individual becomes a non-employee director and $1,000,000 in any other calendar year. We reimburse all reasonable out-of-pocket expenses incurred by directors for their attendance at meetings of our board of directors or any committee thereof. 137 Employee directors receive no additional compensation for their service as a director. 138 Item 11. Executive Compensation Our NEOs for the fiscal year ended December 31, 2025 were: • Allan Reine, M.D., our current Chief Executive Officer; • Keith Gottesdiener, M.D., our former President and Chief Executive Officer from January to May 2025; • Ann Lee, Ph.D., our Chief Technical Officer; and • Jeremy Duffield, M.D., Ph.D., FRCP, our former Chief Scientific Officer from January to July 2025. 2025 Summary Compensation Table The following table sets forth the compensation provided to our NEOs for the fiscal years ended December 31, 2025 and 2024. Name and Principal Position Year Salary ($) Bonus ($) Option Awards ($) (1) Non-Equity Incentive Plan Compensation ($) (2) All Other Compensation ($) Total ($) Allan Reine, M.D. (3) (4) 2025 606,212 — 2,828,798 402,000 57,177 3,894,187 Chief Executive Officer 2024 479,489 176,000 3,699,775 200,000 68,538 4,623,802 Keith Gottesdiener, M.D. (5) 2025 259,568 — 1,185,802 — 762,400 2,207,770 Former Chief Executive Officer 2024 652,792 — 1,165,030 395,010 32,785 2,245,617 Ann Lee, Ph.D. (6) 2025 505,375 — 790,075 243,960 10,706 1,550,116 Chief Technical Officer Jeremy Duffield, M.D., Ph.D., FRCP (7) 2025 268,271 — 668,600 — 380,926 1,317,797 Former Chief Scientific Officer 2024 480,417 — 1,092,033 293,400 11,727 1,877,577 (1) Amounts reflect the aggregate grant date fair value of option awards granted during the applicable year calculated in accordance with the provisions of FASB ASC Topic 718, Compensation—Stock Compensation . Such grant date fair values do not take into account any estimated forfeitures. Refer to Note 2, Summary of Significant Accounting Policies , to our consolidated financial statements appearing elsewhere within this Annual Report on Form 10-K for assumptions underlying the valuation of equity awards. The amounts reported in this column reflect the accounting cost for these options and do not correspond to the actual economic value that may be received by our NEOs upon the exercise of the options or any sale of the underlying shares of common stock. For the year ended December 31, 2025, Dr. Reine was granted time-based and performance-based stock options. The grant date fair value of Dr. Reine’s time-based stock option grant was $2,382,997. The grant date fair value of Dr. Reine’s performance-based stock option grant, based on probable achievement of the applicable performance metrics, was $0; the grant date fair value of such performance-based stock option grant, based on maximum achievement of the applicable performance metrics, was $556,800. Dr. Gottesdiener, Dr. Lee, and Dr. Duffield were granted only time-based stock options during the year ended December 31, 2025. Additionally, the aggregate incremental fair value, calculated in accordance with FASB ASC Topic 718, for the repricing of certain options in 2025 were $445,801 for Dr. Reine and $318,478 for Dr. Lee. Dr. Gottesdiener and Dr. Duffield were not eligible to participate in our option repricing program. Furthermore, the aggregate incremental fair value, calculated in accordance with FASB ASC Topic 718, with respect to the extension of the post-termination exercise period in 2025 for certain options held by Dr. Gottesdiener and Dr. Duffield were $293,602 and $197,002, respectively. (2) The amounts reflect the annual cash incentive compensation earned by our NEOs for the applicable year based on our achievement of certain corporate performance goals. 139 (3) Dr. Reine was appointed as our Chief Executive Officer in May 2025. Prior to his appointment, Dr. Reine served as our Chief Financial Officer. Dr. Reine’s 2025 base salary represents his salary as our former Chief Financial Officer through his transition to Chief Executive Officer and, subsequently, his salary in the role as our Chief Executive Officer. Similarly, Dr. Reine’s annual bonus includes a proration for his tenure as our former Chief Financial Officer. (4) All other compensation for Dr. Reine for 2025 consists of (i) $32,965 in reimbursements for housing expenses, which includes $8,965 for related tax gross-ups, (ii) $13,352 in reimbursement for commuting expenses, which includes $1,702 related tax gross-ups, (iii) $10,500 for matching contributions under our 401(k) plan, and (iv) $360 in wellness reimbursements. (5) All other compensation for Dr. Gottesdiener for 2025 consists of (i) $646,067 of severance, which includes $10,000 of legal reimbursements, (ii) $99,299 in consulting fees under the KMG Consulting Agreement, which is described in greater detail below, (iii) $6,534 in reimbursements for commuting expenses, which includes $846 for related tax gross-ups, and (iv) $10,500 for matching contributions under our 401(k) plan. (6) Dr. Lee was not an NEO for 2024. All other compensation for Dr. Lee for 2025 consists of (i) $10,500 for matching contributions under our 401(k) plan, and (ii) $206 in reimbursements for commuting expense. (7) All other compensation for Dr. Duffield for 2025 consists of (i) $321,154 of severance payments, (ii) $48,900 in consulting fees under the Duffield Consulting Agreement, which is described in greater detail below, (iii) $10,500 for matching contributions under our 401(k) plan, and (iv) $372 in reimbursements for commuting expense. Overview Our executive compensation program is designed to attract, motivate and retain key employees who we believe best represent our values and can make significant contributions towards achieving our purpose of delivering a new class of differentiated one-time curative genetic therapies to address the widest spectrum of diseases by deploying our Prime Editing technology. Our program’s purpose is to incentivize them based on the achievement of key performance goals, and to align their interests with the interests of our stockholders. Under this program, our NEOs’ compensation is based on the achievement of key strategic and business goals that were developed based on our mission. The program consists of a combination of base salary, an annual cash bonus, long-term equity incentive compensation and other employee benefits generally available to our employees, and is designed to align our executive compensation program with the interests of our stockholders by reflecting a pay-for-performance philosophy that supports our business strategy. At the same time, our board of directors believes that the program does not encourage excessive risk-taking by management. Our compensation committee is generally responsible for determining the compensation of our executive officers (and recommending to our board of directors such compensation for our Chief Executive Officer). In setting executive base salaries and bonuses and granting equity incentive awards, the compensation committee considers compensation for comparable positions in the market, the historical compensation levels of our executive officers, internal equity, our desire to motivate our employees to achieve short- and long-term results that are in the best interests of our stockholders, and a long-term commitment to us. We target a general competitive position, based on independent third-party benchmark analytics to inform the mix of compensation of base salary, bonus and long-term incentives. Our compensation committee typically reviews and discusses management’s proposed compensation with our Chief Executive Officer for all executives other than the Chief Executive Officer. Based on those discussions and its discretion, taking into account the factors noted above, the compensation committee then sets the compensation for each executive officer other than the Chief Executive Officer. For the Chief Executive Officer, our compensation committee recommends our Chief Executive Officer’s compensation for approval by our board of directors. Our compensation committee may delegate certain authorities to one of our officers, as described above in “ Corporate Governance—Compensation Committee ”. Our compensation committee has the authority to engage the services of a consulting firm or other outside advisor to assist it in designing our executive compensation programs and in making compensation decisions. During the fiscal year ended December 31, 2025, our compensation committee engaged Alpine Rewards to assist it in evaluating our executive and director compensation practices, including program design, identification of an 140 appropriate peer group for compensation comparison purposes and providing pay benchmarking data. Alpine Rewards also provided (i) analysis and recommendations to our compensation committee regarding trends and emerging topics with respect to executive compensation; (ii) compensation programs for executives, directors and our employees generally; and (iii) stock utilization and related metrics. For further information, see “Corporate Governance—Compensation Committee—Compensation Consultant.” Alpine Rewards reports directly to our compensation committee and did not provide any additional services other than as described above. Our compensation committee annually assesses its independence consistent with Nasdaq listing standards and concluded that the engagement of such consultant did not raise any conflict of interest. 2025 Base Salary Our NEOs each receive a base salary to compensate them for services rendered to us. The base salary payable to each NEO is intended to provide a fixed component of compensation reflecting the executive’s skill set, experience, role and responsibilities. Base salaries may be adjusted from time to time to realign salaries with market levels after taking into account individual responsibilities, performance and experience. For the fiscal year ended December 31, 2025, the annual base salaries for our NEOs were as follows: Name Annual Base Salary from January 1, 2025 through February 28, 2025 Annual Base Salary from March 1, 2025 through May 18, 2025 Annual Base Salary from May 19, 2025 through December 31, 2025 Allan Reine, M.D. (1) $500,000 $517,500 $665,000 Keith Gottesdiener, M.D. (2) $658,350 $681,500 $0 Ann Lee, Ph.D. $491,000 $508,250 $508,250 Jeremy Duffield, M.D., Ph.D., FRCP (2) $483,500 $500,500 $500,500 (1) Dr. Reine was appointed as our Chief Executive Officer effective May 19, 2025. Prior to May 19, 2025, Dr. Reine served as our Chief Financial Officer. (2) Dr. Gottesdiener’s employment with us ceased on May 18, 2025 and Dr. Duffield’s employment with us ceased on July 15, 2025. These NEOs’ base salaries were pro-rated accordingly. 2025 Annual Bonus For the fiscal year ended December 31, 2025, each of the NEOs was eligible to earn an annual cash bonus determined by our compensation committee for NEOs other than the Chief Executive Officer and by our board of directors on the recommendation of our compensation committee, for our principal executive officer, based on our corporate performance. The target annual bonus for each of our NEOs for the fiscal year ended December 31, 2025 was equal to the percentage of the executive’s respective annual base salary as of December 31, 2025 specified below: Name Target Bonus Percentage Allan Reine, M.D. (1) 60% Keith Gottesdiener, M.D. 60% Ann Lee, Ph.D. 40% Jeremy Duffield, M.D., Ph.D., FRCP 40% (1) During his tenure as our former Chief Financial Officer, Dr. Reine’s target bonus percentage was 40%. Upon becoming our Chief Executive Officer, Dr. Reine’s target bonus percentage increased to 60%. In 2025, annual bonuses for our Chief Executive Officer and Chief Technical Officer were based entirely on the level of corporate achievement against our 2025 corporate objectives. With respect to the fiscal year ended December 31, 2025, our compensation committee approved a cash bonus payout in an amount of 120% of target for Dr. Lee and our board of directors approved a cash bonus payout in an amount of 120% of target for Dr. Reine. Dr. Gottesdiener and Dr. Duffield did not earn any annual bonuses for 2025 as a result of their separations from us. 141 Equity-Based Compensation We believe that long-term equity incentives provide our executives with a strong link to our long-term performance and create an ownership culture. These equity awards are a key aspect of our compensation philosophy and serve to align the interests of our executive officers with our stockholders, as they are tied to future increases in the value of our stock. Further, we believe that equity awards with a time-based vesting feature promote retention because this feature incentivizes our NEOs to remain in our employment during the vesting period. Additionally, we believe that equity awards with a performance-based vesting feature further incentivize our executive officers to achieve important milestones. Accordingly, our compensation committee periodically reviews the equity incentive compensation of our NEOs and may grant equity incentive awards to them from time to time. For additional information regarding outstanding equity awards held by our NEOs as of December 31, 2025, see the “Outstanding Equity Awards at Fiscal Year End” table below. Perquisites/Personal Benefits We do not provide significant perquisites or other personal benefits to our executive officers, including our NEOs, except for reimbursements for wellness, commuting and/or housing for certain NEOs, as well as certain related tax gross-ups as described above in the “2025 Summary Compensation Table.” 401(k) Plan We maintain a retirement savings plan, or the 401(k) plan, that is intended to qualify for favorable tax treatment under Section 401(a) of the Code and contains a cash or deferred feature that is intended to meet the requirements of Section 401(k) of the Code. U.S. employees are generally eligible to participate in the 401(k) plan, subject to certain criteria. Participants may make pre-tax and certain after-tax (Roth) salary deferral contributions to the plan from their eligible earnings up to the statutorily prescribed annual limit under the Code. Participants who are 50 years of age or older may contribute additional amounts based on the statutory limits for catch-up contributions. Participants who are 60 to 63 years of age may also contribute additional amounts based on the statutory limits for super catch-up contributions. All deferrals made to the standard catch-up or the super catch-up may only be made on Roth contributions. Participant contributions are held in trust as required by law. We provide matching contributions equal to 50% of an employee’s contributions, subject to a maximum of six percent of eligible compensation. 142 Outstanding Equity Awards at 2025 Fiscal Year-End Table The following table lists all outstanding equity awards held by our NEOs as of December 31, 2025. Equity awards granted prior to our IPO in October 2022 were under our 2019 Stock Option and Grant Plan, as amended from time to time, or the 2019 Plan, and equity awards granted following our IPO were under our 2022 Plan. Options Name Grant Date Vesting Commencement Date Number of Securities Underlying Unexercised Option (#) Exercisable Number of Securities Underlying Unexercised Option (#) Unexercisable Equity Incentive Plan Awards: Number of Securities Underlying Unexercised Unearned Option (#) Option Exercise Price ($) Option Expiration Date Allan Reine, M.D. 05/19/2025 (1) 05/19/2025 — 2,000,000 — 1.34 05/19/2035 05/19/2025 (2) 05/19/2025 — — 500,000 1.34 05/19/2035 02/27/2025 (3) 02/27/2025 57,291 217,709 — 2.42 02/27/2035 01/17/2024 (1) 01/17/2024 287,500 312,500 — 4.04 (8) 01/17/2034 01/17/2024 (4) 01/17/2024 250,000 — — 4.04 (8) 01/17/2034 Keith Gottesdiener, M.D. 02/28/2025 (5) 02/28/2025 104,166 395,834 — 2.52 02/28/2035 02/25/2024 (5) 02/25/2024 45,833 54,167 — 8.32 02/25/2034 02/25/2024 (6) 02/25/2025 200,000 — 200,000 8.32 02/25/2034 03/31/2023 (5) 03/31/2023 342,194 155,544 — 12.30 03/31/2033 10/27/2021 (5) 10/27/2021 241,250 — — 3.67 10/27/2031 Ann Lee, Ph.D. 02/27/2025 (3) 02/27/2025 57,291 217,709 — 2.42 02/27/2035 02/21/2024 (3) 02/21/2024 82,956 98,039 — 4.04 (8) 02/21/2034 03/31/2023 (3) 03/31/2023 124,434 56,561 — 4.04 (8) 03/31/2033 10/27/2021 (4) 10/04/2021 482,501 — — 3.67 10/26/2031 10/27/2021 (4) 10/04/2021 241,248 — — 3.67 10/26/2031 Jeremy Duffield, M.D., Ph.D., FRCP 02/27/2025 (7) 02/27/2025 57,291 217,709 — 2.42 02/27/2035 02/21/2024 (7) 02/21/2024 82,956 98,039 — 8.49 02/21/2034 03/31/2023 (7) 03/31/2023 124,434 56,561 — 12.30 03/31/2033 10/27/2021 (7) 10/27/2021 16,083 — — 3.67 10/27/2031 143 (1) The shares underlying these options vest as follows: 25 percent vest on the 1-year anniversary of the vesting commencement date, and 1/48th of the shares vest on a monthly basis thereafter, in each case subject to the applicable NEO’s continuous service relationship with us through each applicable vesting date. The stock options are also subject to certain acceleration of vesting provisions as provided in the applicable NEO’s employment agreement. (2) The underlying shares vest upon the achievement of pre-determined milestone(s), subject to the applicable NEO’s continuous service relationship with us through the applicable vesting date. As of December 31, 2025, the applicable milestone(s) have not been satisfied. (3) The shares underlying these options vest in equal monthly installments over 48 months commencing on the vesting commencement date, subject to the applicable NEO’s continuous service relationship with us through each applicable vesting date. The stock options are also subject to certain acceleration of vesting provisions as provided in the applicable NEO’s employment agreement. (4) The underlying shares are fully vested as of December 31, 2025. (5) The shares underlying these options vest in equal monthly installments over 48 months commencing on the vesting commencement date. Under the terms of the Gottesdiener Separation Agreement, as defined and described in greater detail below, options granted to Dr. Gottesdiener while an employee will continue to vest for one additional year following the cessation of his employment, subject to Dr. Gottesdiener’s continued service relationship with us through each applicable vesting date. (6) The underlying shares vest in four tranches (consisting of 100,000 shares each) upon the achievement of a pre-determined milestone for each tranche prior to one year additional vesting period provided for under the defined the Gottesdiener Separation Agreement, subject to Dr. Gottesdiener’s continued service relationship with us through each applicable vesting date. As of December 31, 2025, two of the four tranches have not vested. (7) The shares underlying these options vest in equal monthly installments over 48 months commencing on the vesting commencement date and through March 31, 2026, the last date of Duffield Consulting Agreement, as defined and described in detail below, subject to Dr. Duffield’s continued service relationship with us through each applicable vesting date. (8) All options issued under the 2019 Plan and 2022 Plan to Dr. Lee and Dr. Reine with an exercise price greater than $4.04 were repriced on August 1, 2025, as approved by our stockholders. Refer to Note 8, Stock-based Compensation, to our consolidated financial statements appearing elsewhere within this Annual Report on Form 10-K for greater detail. Agreements with our NEOs We have entered into a new employment agreement with Dr. Reine that was effective as of May 2025. Previously, we entered into an employment agreement with Dr. Reine that was effective as of January 2024. We entered into employment agreements with Dr. Gottesdiener, Dr. Duffield, and Dr. Lee that were effective in July 2022. We entered into a separation agreement with Dr. Gottesdiener and a consulting agreement with a limited liability company managed by Dr. Gottesdiener in May 2025. We entered into a separation agreement and consulting agreement with Dr. Duffield in July 2025. Each of our NEOs are subject to standard confidentiality and nondisclosure, assignment of intellectual property work product and post-termination non-solicitation of employees, consultants and customers covenants and, in certain circumstances, non-competition covenants. Allan Reine, M.D. CEO Agreement In connection with Dr. Reine’s appointment as our Chief Executive Officer, we entered into an Amended and Restated Employment Agreement, or the Reine CEO Employment Agreement, effective May 19, 2025. The Reine CEO Employment Agreement provides for at-will employment. The agreement also sets forth initial base salary, initial annual target bonus and eligibility to participate in our benefit plans generally. In addition, Dr. Reine is 144 entitled to reimbursement for commuting expenses, which include all reasonable costs for his commute between his residence in New York, New York and our corporate headquarters in Cambridge, Massachusetts, as well as reimbursement for housing expenses in or near Cambridge, Massachusetts. Pursuant to the Reine CEO Employment Agreement, in the event Dr. Reine is terminated by us without “Cause” or he resigns for “Good Reason” (as such terms are defined in the Reine CEO Employment Agreement), in each case subject to the delivery of and compliance with a fully effective separation agreement that shall include, without limitation, a general release of claims, reaffirmation of applicable restrictive covenants and, in our discretion, a one year non-competition agreement, Dr. Reine will be entitled to (i) an amount equal to the sum of (A) twelve (12) months of his then-current base salary plus (B) 1.0 times his target annual bonus for the then current year, in each case subject to reductions by any amount received by him pursuant to a restrictive covenant agreement, and (ii) subject to Dr. Reine’s co-payment of premium amounts at the applicable active employees’ rate and proper election to continue COBRA health coverage, payment of the portion of the premium equal to the amount we would have paid to provide health insurance had he remained employed by us until the earliest of (A) twelve (12) months following his termination, (B) his eligibility for group medical plan benefits under any other employer’s group medical plan or (C) the end of his COBRA health continuation period. These amounts shall be paid out in substantially equal installments in accordance with our payroll practice over a period of twelve (12) months. In addition, subject to the delivery of the fully effective separation agreement, the bonus amount (if any) that Dr. Reine would have been paid if he had remained employed through the payment date, if such termination occurs on or after January 1 but before the date bonuses are paid for the prior year to our other executives, will be paid to Dr. Reine on the date our other executives receive their bonuses. In the event Dr. Reine is terminated by us without “Cause” or he resigns for “Good Reason”, in each case within three months prior and 12 months following a “Change in Control” (as such terms are defined in the Reine CEO Employment Agreement), subject to the delivery of and compliance with a fully effective separation agreement (as described above), Dr. Reine will be entitled to the following, in lieu of the benefits above: (i) a lump sum cash payment equal to the sum of (A) 18 months of his then-current base salary (or his base salary in effect immediately prior to the “Change in Control,” if higher) plus (B) 1.5 times his target annual bonus for the then current year (or target in effect immediately prior to the “Change in Control,” if higher), in each case subject to reductions by any amount received by him pursuant to a restrictive covenant agreement, (ii) subject to Dr. Reine’s co-payment of premium amounts at the applicable active employees’ rate and proper election to continue COBRA health coverage, payment of the portion of the premium equal to the amount we would have paid to provide health insurance had he remained employed by us until the earliest of (A) 18 months from the date of his separation, (B) his eligibility for group medical plan benefits under any other employer’s group medical plan or (C) the end of his COBRA health continuation period, and (iii) the bonus amount (if any) that Dr. Reine would have been paid if he had remained employed through the payment date, if such termination occurs on or after January 1 but before the date bonuses are paid for the prior year to our other executives. In addition, in the event Dr. Reine is terminated by us without Cause or he resigns for Good Reason, in each case within three months prior and 12 months following a “Change in Control,” all of the then-outstanding and unvested portion of his stock options and other stock-based awards that are subject solely to time-based vesting shall become fully vested and exercisable or non-forfeitable immediately as of the date of termination, with any such performance-based awards vesting at target. The payments and benefits provided under the Reine CEO Employment Agreement in connection with a “Change in Control” may not be eligible for federal income tax deduction for us pursuant to Section 280G of the Code. These payments and benefits may also be subject to an excise tax under Section 4999 of the Code. If the payments or benefits payable to Dr. Reine in connection with a “Change in Control” would be subject to the excise tax imposed under Section 4999 of the Code, then those payments or benefits will be reduced if such reduction would result in a higher net after-tax benefit to him. CFO Agreement In January 2024, we entered into an employment agreement with Dr. Reine pursuant to which we employed Dr. Reine as our former Chief Financial Officer, or the Reine CFO Employment Agreement. The agreement set forth Dr. Reine’s initial base salary, initial annual target bonus and eligibility to participate in our benefit plans generally. In addition, Dr. Reine was entitled to reimbursement for commuting expenses, which include all reasonable costs for his commute between his residence in New York, New York and our corporate headquarters in Cambridge, 145 Massachusetts, as well as reimbursement for housing expenses in or near Cambridge, Massachusetts, for up to $2,000 per month for 12 months from the commencement of his employment. Keith M. Gottesdiener, M.D. Employment Agreement The employment agreement with Dr. Gottesdiener, or the Gottesdiener Employment Agreement, provided for at-will employment. The agreement also set forth initial base salary, initial annual target bonus and eligibility to participate in our benefit plans generally. In addition, pursuant to Amendment No. 1 to the Gottesdiener Employment Agreement, Dr. Gottesdiener was entitled to reimbursement for commuting expenses, which include all reasonable costs for his commute between his family’s residence in New York, New York and our corporate headquarters in Cambridge, Massachusetts. Separation Agreement In May 2025, we entered into a separation agreement with Dr. Gottesdiener, or the Gottesdiener Separation Agreement, pursuant to which Dr. Gottesdiener is entitled to receive certain severance benefits in accordance with the terms of the Gottesdiener Employment Agreement. Pursuant to the Gottesdiener Separation Agreement, in exchange for, among other things, a release of claims, reaffirmation of applicable restrictive covenants, and a one-year non-competition agreement, Dr. Gottesdiener is entitled to (i) an amount equal to the sum of (A) 12 months of his then-current base salary plus (B) one times his target bonus (as defined in the Gottesdiener Employment Agreement) for 2025, to be paid out in substantially equal installments in accordance with our payroll practices over a period of 12 months, (ii) subject to his copayment of premium amounts at the applicable active employees’ rate and his proper election to receive COBRA health coverage, payment of the portion of the premium equal to the amount we would have paid to provide health insurance had he remained employed by us until the earliest of (A) 12 months following his termination, (B) his eligibility for group medical plan benefits under any other employer’s group medical plan or (C) the end of his COBRA health continuation period. The Gottesdiener Separation Agreement also provides that, if Dr. Gottesdiener enters into the Gottesdiener Advisor Agreement, as defined and described below, with us, he will continue to vest in his outstanding unvested equity awards during the advisory period (for up to one-year following the date of separation of employment), subject to the terms of the Gottesdiener Advisor Agreement, the applicable equity award agreements, and the 2019 Plan and 2022 Plan. Consulting Agreement In May 2025, pursuant to the Gottesdiener Separation Agreement and Gottesdiener Employment Agreement, we entered into a consulting agreement with KMG Strategic Consulting, LLC, or the KMG Consulting Agreement, a limited liability company managed by Dr. Gottesdiener, to provide for Dr. Gottesdiener’s continued consulting services to us. Pursuant to the KMG Consulting Agreement, Dr. Gottesdiener will provide advice and assistance in the area of his expertise. In exchange, we agreed to pay KMG an hourly rate of $1,000 and reimburse KMG for any pre-approved actual expenses incurred. The KMG Consulting Agreement has a term of one-year unless (i) earlier terminated by one of the parties or (ii) extended upon mutual written agreement of the parties. Advisory Services Agreement In May 2025, pursuant to the Gottesdiener Separation Agreement and Gottesdiener Employment Agreement, we entered into an advisory services agreement with Dr. Gottesdiener, or the Gottesdiener Advisor Agreement, to retain certain non-exclusive, limited consulting and advisory services of Dr. Gottesdiener for a period of up to one year from the date of his separation. Pursuant to the Gottesdiener Advisor Agreement, Dr. Gottesdiener will provide advice and assistance in the area of his expertise. In exchange, (i) Dr. Gottesdiener will continue to vest in his outstanding, unvested equity awards 146 during the term of the Gottesdiener Advisor Agreement; (ii) following the termination of the Gottesdiener Advisor Agreement, the post-termination exercise period for any vested stock options as of the last date of the term of the Gottesdiener Advisor Agreement will be extended to the earlier of (A) the 48 month anniversary of the last date of the term, or (B) the original expiration of such stock options, as applicable; and (iii) we agreed to reimburse Dr. Gottesdiener for any pre-approved actual expenses incurred. The Gottesdiener Advisor Agreement has a term of one-year unless earlier terminated in accordance with the terms described therein. Ann L. Lee, Ph.D. The employment agreement with Dr. Lee, or the Lee Employment Agreement, provides for at-will employment. The agreement also sets forth initial base salary, initial annual target bonus and eligibility to participate in our benefit plans generally. The agreement also sets forth initial base salary, initial annual target bonus and eligibility to participate in our benefit plans generally. Pursuant to the Lee Employment Agreement, in the event Dr. Lee is terminated by us without “Cause” or she resigns for “Good Reason” (as such terms are defined in the Lee Employment Agreement), in each case subject to the delivery of and compliance with a fully effective separation agreement that shall include, without limitation, a release of claims, reaffirmation of applicable restrictive covenants and, in our discretion, a one year non-competition agreement, Dr. Lee will be entitled to (i) an amount equal to the sum of (A) nine months of her then-current base salary plus (B) 0.75 times her target annual bonus for the then current year, in each case subject to reductions by any amount received by her pursuant to a restrictive covenant agreement, and (ii) subject to Dr. Lee’s co-payment of premium amounts at the applicable active employees’ rate and proper election to continue COBRA health coverage, payment of the portion of the premium equal to the amount we would have paid to provide health insurance had she remained employed by us until the earliest of (A) nine months following her termination, (B) her eligibility for group medical plan benefits under any other employer’s group medical plan or (C) the end of her COBRA health continuation period. These amounts shall be paid out in substantially equal installments in accordance with our payroll practice over a period of nine months. In addition, subject to the delivery of the fully effective separation agreement, the bonus amount (if any) that Dr. Lee would have been paid if she had remained employed through the payment date, if such termination occurs on or after January 1 but before the date bonuses are paid for the prior year to our other executives, will be paid to Dr. Lee on the date our other executives receive their bonuses. In the event Dr. Lee is terminated by us without “Cause” or she resigns for “Good Reason”, in each case within 12 months following a ”Change in Control” (as defined in the Lee Employment Agreement), subject to the delivery of and compliance with a fully effective separation agreement (as described above), Dr. Lee will be entitled to the following, in lieu of the benefits above: (i) a lump sum cash payment equal to the sum of (A) 12 months of her then-current base salary (or her base salary in effect immediately prior to the “Change in Control,” if higher) plus (B) 1.0 times her target annual bonus for the then current year (or target in effect immediately prior to the “Change in Control,” if higher), in each case subject to reductions by any amount received by her pursuant to a restrictive covenant agreement, (ii) subject to Dr. Lee’s co-payment of premium amounts at the applicable active employees’ rate and proper election to continue COBRA health coverage, payment of the portion of the premium equal to the amount we would have paid to provide health insurance had she remained employed by us until the earliest of (A) 12 months from the date of her separation, (B) her eligibility for group medical plan benefits under any other employer’s group medical plan or (C) the end of her COBRA health continuation period, and (iii) the bonus amount (if any) that Dr. Lee would have been paid if she had remained employed through the payment date, if such termination occurs on or after January 1 but before the date bonuses are paid for the prior year to our other executives. In addition, in the event Dr. Lee is terminated by us without Cause or she resigns for Good Reason, in each case within 12 months following a “Change in Control” (as defined in the Lee Employment Agreement), all of the then-outstanding and unvested portion of her stock options and other stock-based awards that (i) are subject solely to time-based vesting or (ii) were granted to Dr. Lee prior to the effective date of the Lee Employment Agreement and are subject to performance-based vesting shall become fully vested and exercisable or non-forfeitable immediately as of the date of termination, with any such performance-based awards vesting at target. The payments and benefits provided under the Lee Employment Agreement in connection with a “Change in Control” may not be eligible for federal income tax deduction for us pursuant to Section 280G of the Code. These payments and benefits may also be subject to an excise tax under Section 4999 of the Code. If the payments or benefits payable to Dr. Lee in connection with a “Change in Control” would be subject to the excise tax imposed 147 under Section 4999 of the Code, then those payments or benefits will be reduced if such reduction would result in a higher net after-tax benefit to her. Jeremy Duffield, M.D. Ph.D., FRCP Employment Agreement The employment agreement with Dr. Duffield, or the Duffield Employment Agreement, provided for at-will employment. The agreement also set forth his initial base salary, initial annual target bonus and eligibility to participate in our benefit plans generally. Separation Agreement In July 2025, Dr. Duffield entered into a Separation Agreement with us, or the Duffield Separation Agreement, pursuant to which Dr. Duffield is entitled to receive certain severance benefits in accordance with the terms of the Duffield Employment Agreement. Pursuant to the Duffield Separation Agreement, in exchange for, among other things, a release of claims, reaffirmation of applicable restrictive covenants, and a one-year noncompetition agreement, Dr. Duffield is entitled to (i) an amount equal to the sum of (A) nine months of his then-current base salary plus (B) 0.75 his target bonus (as defined in the Duffield Employment Agreement) for 2025, to be paid out in substantially equal installments in accordance with our payroll practices over a period of nine months, (ii) subject to his copayment of premium amounts at the applicable active employees’ rate and his proper election to receive COBRA health coverage, payment of the portion of the premium equal to the amount we would have paid to provide health insurance had he remained employed by us until the earliest of (A) 12 months following his termination, (B) his eligibility for group medical plan benefits under any other employer’s group medical plan or (C) the end of his COBRA health continuation period. The Duffield Separation Agreement also provides that his service relationship for the purposes of vesting in any of the Company’s outstanding unvested stock options ends on the later of (i) the date his employment terminated, or (ii) the termination of a consulting agreement entered into between Dr. Duffield and us in July 2025, or the Duffield Consulting Agreement. The Duffield Separation Agreement further provides that upon the termination of the Duffield Consulting Agreement, any and all stock options held by him that are outstanding and vested shall be exercisable until the date that is four months following the termination of the Duffield Consulting Agreement. In July 2025, our compensation committee approved an extension of the post-termination exercise period for such options until 12 months following the termination of the Duffield Consulting Agreement. Consulting Agreement In July 2025, Dr. Duffield entered into the Duffield Consulting Agreement with us, pursuant to which Dr. Duffield will provide advice and assistance in the area of his expertise. In exchange, we agree to pay Dr. Duffield an hourly rate of $600 and reimburse him for any pre-approved actual expenses incurred. The Duffield Consulting Agreement will continue until March 31, 2026, unless (i) earlier terminated by one of the parties or (ii) extended upon mutual written agreement of the parties. 148 Item 12. Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters. Equity Compensation Plan Information The following table provides information as of December 31, 2025 with respect to the shares of our common stock that may be issued under our existing equity compensation plans: Plan category Number of securities to be issued upon exercise of outstanding options, warrants and rights Weighted-average exercise price of outstanding options, warrants and rights Number of securities remaining available for future issuance under equity compensation plans (excluding securities reflected in first column) Equity compensation plans approved by security holders Stock options (1) (2) 17,966,867 $ 3.76 7,891,263 2022 Employee Stock Purchase Plan (3) (4) — — 1,522,025 Equity compensation plans not approved by security holders — — — Total 17,966,867 $ 3.76 9,413,288 (1) Number of shares to be issued pursuant to outstanding options includes 15,637,303 time-based stock options with a weighted-average exercise price of $3.76 outstanding under our 2019 Plan and our 2022 Plan, 2,029,564 performance-based stock options with a weighted-average exercise price of $4.10 under our 2019 Plan and our 2022 Plan, and 300,000 market-based stock options with a weighted-average exercise price of $1.34 under our 2022 Plan. (2) Shares of our common stock available for future issuance as of December 31, 2025 pursuant to the 2022 Plan excludes the 9,025,700 shares that were added to the plan as a result of the automatic annual increase on January 1, 2026. The 2022 Plan provides that the number of shares reserved and available for issuance under the 2022 Plan will automatically increase on January 1, 2023 and each January 1 thereafter, by five percent of the outstanding number of shares of common stock on the immediately preceding December 31 or such lesser number of shares as determined by the compensation committee. The Company no longer makes grants under the 2019 Plan. The shares of common stock underlying any awards under the 2022 Plan and the 2019 Plan that are forfeited, cancelled, held back upon exercise or settlement of an award to satisfy the exercise price or tax withholding, reacquired by the Company prior to vesting, satisfied without the issuance of stock, expire or are otherwise terminated (other than by exercise) will be added back to the shares of common stock available for issuance under the 2022 Plan. (3) Number of securities to be issued upon exercise of outstanding options, warrants and rights excludes purchase rights accruing under the 2022 Employee Stock Purchase Plan, as amended from time to time, or the 2022 ESPP, because the purchase rights (and, therefore, the number of shares to be purchased) will not be determined until the end of the offering period, which will occur after December 31, 2025. (4) Shares of our common stock available for future issuance as of December 31, 2025 pursuant to the 2022 ESPP includes shares that are expected to be issued at the close of the ESPP offering period that was ongoing at December 31, 2025, as the exact number of shares to be issued will not be known until the end of the offering period, which will occur after December 31, 2025. The 2022 ESPP provides that the number of shares common stock that may be issued under the 2022 ESPP plan shall cumulatively increase beginning on January 1, 2023 and each January 1 thereafter through January 1, 2032, by the least of (i) 971,350 shares of common stock, (ii) one percent of the outstanding number of shares of common stock on the immediately preceding December 31 or (iii) such number of shares of common stock as determined by the administrator of the 2022 ESPP. The Company did not add shares to the 2022 ESPP on January 1, 2026. 149 Security Ownership of Certain Beneficial Owners and Management The following table sets forth information, as of February 12, 2026, unless otherwise indicated, regarding the beneficial ownership of our common stock for (i) stockholders who beneficially owned more than 5% of our common stock, (ii) each of our directors and NEOs, and (iii) all of our directors and executive officers as a group. The number of shares beneficially owned by each stockholder is determined under rules issued by the SEC. Under these rules, a person is deemed to be a “beneficial” owner of a security if that person has or shares voting power or investment power, which includes the power to dispose of or to direct the disposition of such security. Except as indicated in the footnotes below, we believe, based on the information furnished to us, that the individuals and entities named in the table below have sole voting and investment power with respect to all shares of common stock beneficially owned by them, subject to any applicable community property laws. In computing the number of shares beneficially owned by an individual or entity, shares of common stock subject to options, warrants, restricted stock units or other rights held by such person that are currently exercisable or have vested or that will become exercisable or will have vested within 60 days of February 12, 2026 are considered outstanding, although these shares are not considered outstanding for purposes of computing the percentage ownership of any other person. On February 12, 2026, there were 180,551,436 shares of our common stock outstanding. Unless noted otherwise, the address of all listed stockholders is c/o Prime Medicine, Inc., 60 First Street, Cambridge, MA 02141. Shares of Common Stock Beneficially Owned Percentage of Shares Beneficially Owned 5% or Greater Stockholders David Liu (1) 20,334,460 11.26 % Entities affiliated with ARCH Venture Partners (2) 18,486,894 10.24 % Entities affiliated with GV (3) 16,562,498 9.17 % Bristol-Myers Squibb Company (4) 11,006,163 6.10 % Directors and Named Executive Officers Allan Reine (5) 774,479 * Keith Gottesdiener (6) 5,363,130 2.97 % Ann Lee (7) 1,128,242 * Jeremy Duffield (8) 1,285,577 * Thomas Cahill (9) 84,062 * Wendy Chung (9) 106,578 * Kaye Foster (9) 106,578 * Michael Kelly (9) 106,578 * Jeffrey Marrazzo (9) 564,666 * Robert Nelsen (2) (10) 18,587,036 10.29 % David Schenkein (9) 84,062 * All executive officers and directors as a group (11 persons) 28,190,988 15.61 % * Less than one percent. (1) Consists of: (a) 20,240,945 shares of common stock, and (b) 93,515 shares of common stock underlying options exercisable within 60 days of February 12, 2026. (2) Information herein is based on Schedule 13D/A filed with the SEC on August 11, 2025 by (1) ARCH Venture Fund X, L.P., or AVF X, (2) ARCH Venture Partners X, L.P., or AVP X LP, which is the sole general partner of AVF X, (3) ARCH Venture Partners X, LLC, or AVP X LLC, which is the sole general partner of AVP X LP and AVP X Overage LP (defined below), (4) ARCH Venture Fund X Overage, L.P., or AVF X Overage, (5) ARCH Venture Partners X Overage, L.P., or AVP X Overage LP, which is the sole general partner of AVF X 150 Overage, (6) ARCH Venture Fund XII, L.P., or AVF XII, (7) ARCH Venture Partners XII, L.P., or AVP XII LP, which is the sole general partner of AVF XII, (8) ARCH Venture Partners XII, LLC, or AVP XII LLC, which is the sole general partner of AVP XII LP, (9) Keith Crandell, or Crandell, (10) Robert Nelsen, or Nelsen, a member of our board of directors, (11) Kristina Burow, or Burow, and (12) Steven Gillis, or Gillis”, and together with Nelsen, Crandell and Burow, referred to individually as “Committee Member or collectively as either the “AVP X Investment Committee Members” or the “AVP XII Investment Committee Members. Each of the individuals and entities above shall be referred to herein as an “ARCH Reporting Person” and collectively as the “ARCH Reporting Persons.” AVP X LP and AVP X Overage LP may be deemed to beneficially own the shares held by AVF X and AVF X Overage, respectively; AVP X LLC may be deemed to beneficially own the shares held by AVF X; AVP XII LP may be deemed to beneficially own the shares held by AVF XII; AVP XII LLC may be deemed to beneficially own the shares held by AVF XII; and each of the Committee Members may be deemed to share the power to direct the disposition and vote of the shares held by AVF X, AVF X Overage and AVF XII. The ARCH Reporting Persons each disclaims beneficial ownership except to any pecuniary interest therein. Consists of: (a) 6,128,297 shares of common stock held by AVF X, (b) 6,128,297 shares of common stock held by AVF X Overage, and (c) 6,230,300 shares of common stock held by AVF XII. The address of all entities and individuals referenced in this footnote is 8755 W. Higgins Road, Suite 1025, Chicago, IL 60631. (3) Information herein is based on Schedule 13G/A filed with the SEC on November 12, 2025 by GV 2019, L.P., GV 2019 GP, L.P., GV 2019 GP, L.L.C., GV 2021, L.P., GV 2021 GP, L.P., GV 2021 GP, L.L.C., GV 2023, L.P., GV 2023 GP, L.P., GV 2023 GP, L.L.C., Alphabet Holdings LLC, XXVI Holdings Inc. and Alphabet Inc. Consists of: (a) 10,100,058 shares of common stock held by GV 2019, L.P., or GV 2019, (b) 3,262,440 shares of common stock held by GV 2021, L.P., or GV 2021, and (c) 3,200,000 shares of common stock held by GV 2023, L.P., or GV 2023. The general partner of the GV 2019, L.P., or the 2019 Partnership, is GV 2019 GP, L.P., or 2019 GP. The general partner of 2019 GP is GV 2019 GP, L.L.C., or 2019 LLC. The sole member of 2019 LLC is Alphabet Holdings LLC, or Alphabet Holdings. The sole member of Alphabet Holdings is XXVI Holdings Inc., or XXVI. The controlling stockholder of XXVI is Alphabet Inc. (Alphabet Inc., together with 2019 GP, 2019 LLC, Alphabet Holdings, and XXVI may be collectively referred to as the 2019 Partnership Affiliates. Each of the 2019 Partnership Affiliates may be deemed to indirectly beneficially own (as that term is defined in Rule 13d-3 of the Exchange Act) the securities directly beneficially owned by the 2019 Partnership. The general partner of the GV 2021, L.P., or the 2021 Partnership is GV 2021 GP, L.P., or 2021 GP. The general partner of 2021 GP is GV 2021 GP, L.L.C., or 2021 LLC. The sole member of 2021 LLC is Alphabet Holdings. The sole member of Alphabet Holdings is XXVI. The controlling stockholder of XXVI is Alphabet Inc. (Alphabet Inc., together with 2021 GP, 2021 LLC, Alphabet Holdings, and XXVI may be referred to as the 2021 Partnership Affiliates). Each of the 2021 Partnership Affiliates may be deemed to indirectly beneficially own (as that term is defined in Rule 13d-3 of the Exchange Act) the securities directly beneficially owned by the 2021 Partnership. The general partner of the GV 2023, L.P., or the 2023 Partnership is GV 2023 GP, L.P., or 2023 GP. The general partner of 2023 GP is GV 2023 GP, L.L.C., or 2023 LLC. The sole member of 2023 LLC is Alphabet Holdings. The sole member of Alphabet Holdings is XXVI. The controlling stockholder of XXVI is Alphabet Inc. (Alphabet Inc., together with 2023 GP, 2023 LLC, Alphabet Holdings, and XXVI may be referred to as the 2023 Partnership Affiliates. Each of the 2023 Partnership Affiliates may be deemed to indirectly beneficially own (as that term is defined in Rule 13d-3 of the Exchange Act) the securities directly beneficially owned by the 2023 Partnership. The principal business address for all entities referenced in this footnote is 1600 Amphitheatre Parkway, Mountain View, CA 94043. (4) Information herein is based on Schedule 13G filed with the SEC on October 4, 2024 by BMS. The address of BMS is Route 206 & Province Line Road, Princeton, NJ 08543. 151 (5) Consists of: (a) 125,000 shares of common stock held by Dr. Reine, and (b) 649,479 shares of common stock underlying options exercisable within 60 days of February 12, 2026. (6) Information herein is based solely on Form 4 filed with the SEC on October 10, 2024 by the Company on behalf of Dr. Gottesdiener and on the Company’s records. Dr. Gottesdiener shareholdings consists of: (a) 2,310,837 shares of common stock held by Dr. Gottesdiener, (b) 50,241 shares of common stock held by Dr. Gottesdiener’s spouse, (c) 682,259 shares of common stock held by the Coolidge GST Trust-2022, or the Coolidge Trust Shares, and (d) 1,317,741 shares of common stock held by the Gottesdiener Family GST Trust, or the Gottesdiener Family Trust Shares. Dr. Gottesdiener disclaims beneficial ownership of the Coolidge Trust Shares and the Gottesdiener Family Trust Shares. In addition, this is also inclusive of 1,002,052 shares of common stock underlying options exercisable within 60 days of February 12, 2026. (7) Consists of: (a) 100,000 shares of common stock held by Dr. Lee, and (b) 1,028,242 shares of common stock underlying options exercisable within 60 days of February 12, 2026. (8) Information herein is based solely on Form 4 filed with the SEC on October 19, 2022 by the Company on behalf of Dr. Duffield and on the Company’s records. Dr. Duffield directly holds 965,001 shares of common stock. In addition, this is also inclusive of 320,576 shares of common stock underlying options exercisable within 60 days of February 12, 2026. (9) Consists entirely of shares of common stock underlying options exercisable within 60 days of February 12, 2026. (10) Consists of: (a) 84,062 shares of common stock underlying options exercisable within 60 days of February 12, 2026 and (b) 16,080 shares of common stock held by a trust for the benefit of Mr. Nelsen’s family members. 152 Item 13. Certain Relationships and Related Transactions, and Director Independence Other than the compensation arrangements for our NEOs and our directors described in Item 11, Executive Compensation , of this Annual Report on Form 10-K, set forth below is a description of transactions or series of transactions since January 1, 2024, to which we were or will be a party, and in which: • the amount involved in the transaction exceeds, or will exceed, $120,000 (or, if less, 1% of the average of our total asset amounts at December 31, 2024 and 2025); and • in which any of our executive officers, directors or holder of five percent or more of any class of our capital stock, including their immediate family members or affiliated entities, had or will have a direct or indirect material interest. Participation in our Follow-on Public Offerings Our 5% stockholders, their affiliates, and certain affiliated entities affiliated with our directors purchased an aggregate of (i) 7,200,000 shares of our common stock in our follow-on public offering in February 2024 at the public offering price, and (ii) an aggregate of 4,545,455 shares of our common stock in our follow-on public offering in August 2025 at the public offering price. The following table sets forth the number of shares of our common stock purchased by our 5% stockholders, their affiliates, and certain affiliated entities affiliated with our directors and the aggregate purchase price paid for such shares. Stockholder(1) Shares of common stock Total purchase price February 2024 follow-on public offering GV 2023, L.P. (2) 3,200,000 $ 20,000,000 Entities affiliated with ARCH Venture Partners (3) 3,200,000 $ 20,000,000 Newpath Partners, L.P. (4) 800,000 $ 5,000,000 August 2025 follow-on public offering Entities affiliated with ARCH Venture Partners (3) 3,030,303 $ 9,999,990 GV 2021, L.P. (2) 1,515,152 $ 5,000,002 (1) Additional details regarding certain of these investors and their equity holdings are provided in Item 12, Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters , of this Annual Report on Form 10-K. (2) David Schenkein serves as a member of our board of directors and is an affiliate of GV, of which GV 2021, L.P. and GV 2023, L.P. are affiliated funds. Entities affiliated with GV collectively hold more than five percent of our voting securities. (3) Robert Nelsen serves as a member of our board of directors and is an affiliate of ARCH Venture Partners, of which ARCH Venture Fund X Overage, L.P., ARCH Venture Fund X, L.P., and ARCH Venture Fund XII, L.P. are affiliated funds. Entities affiliated with ARCH Venture Partners collectively hold more than five percent of our voting securities. (4) Thomas Cahill serves as a member of our board of directors and is an affiliate of Newpath Partners, of which Newpath Partners, L.P. is an affiliated fund. Agreements with BMS Research Collaboration and License Agreement In September 2024, we entered into the BMS Collaboration Agreement with Juno. BMS became a beneficial owner of more than 5% of our voting securities as a result of this transaction. Pursuant to the BMS Collaboration Agreement, we granted to BMS an exclusive worldwide license to certain Prime Editing technology for developing, manufacturing and commercializing ex vivo T-cell therapeutic products directed to select targets. Under the BMS Collaboration Agreement, we received a $55.0 million upfront payment and received a $55.0 million equity 153 investment from BMS (as described below). We are also eligible to receive more than $3.5 billion in milestones, including up to $185.0 million in preclinical milestones, up to $1.2 billion in development milestones, and up to $2.1 billion in commercialization milestones, along with royalties on net sales. Unless earlier terminated, the term of the BMS Collaboration Agreement continues until expiration of the last royalty term for the applicable product in the applicable country. The BMS Collaboration Agreement is subject to customary termination provisions, including termination by a party for the other party’s uncured, material breach. Stock Purchase Agreement In September 2024, we entered into a stock purchase agreement with BMS, or the BMS Purchase Agreement, pursuant to which we agreed to issue and sell, and BMS agreed to purchase, 11,006,163 shares of our common stock, or the BMS Shares, for an aggregate purchase price of $55.0 million pursuant to the terms and conditions thereof. Pursuant to the terms of the BMS Purchase Agreement, BMS has agreed not to, directly or indirectly, sell or transfer any of the BMS Shares until September 30, 2027 subject to specified conditions and exceptions. In addition, we agreed, among other things, to file with the SEC a registration statement covering the resale of the BMS Shares and to use commercially reasonable efforts to cause such registration statement to become effective on or prior to ninety (90) calendar days after closing. We filed the registration statement on Form S-3 covering the resale of the BMS Shares with the SEC on December 13, 2024, which became effective on December 20, 2024. We have also agreed to customary indemnification obligations under the BMS Purchase Agreement. Advisory Services Agreement with Jeffrey Marrazzo Pursuant to an advisory services agreement with Jeffrey Marrazzo, a member of our board of directors, or the Marrazzo Agreement, dated February 29, 2024, Mr. Marrazzo agreed to provide certain professional services to the Company separate from and in addition to his service as a member of our board of directors, and we agreed to pay Mr. Marrazzo an annual fee of $50,000 per year in addition to the grant of an option to purchase 250,000 shares of the Company’s common stock. The Marrazzo Agreement expired in February 2025. From January 1, 2024 through the termination date, we paid Mr. Marrazzo $50,000 and granted Mr. Marrazzo 250,000 stock options under the Marrazzo Agreement. Executive Chair Agreement with Jeffrey Marrazzo Pursuant to an executive chair agreement with Jeffrey Marrazzo, a member of our board of directors, or the Executive Chair Agreement, dated May 19, 2025, Mr. Marrazzo agreed to provide services as the executive chair of our board of directors, and we agreed to pay Mr. Marrazzo an annual fee of $100,000 per year in addition to the grant of options to purchase a total of 1,000,000 shares of the Company’s common stock consisting of (i) a time-based option to purchase 500,000 shares, (ii) a performance-based option to purchase 200,000 shares, and (iii) a stock price-based option to purchase 300,000 shares. The Executive Chair Agreement will continue indefinitely until terminated in accordance with its terms. If the Executive Chair Agreement is terminated between six-months and one-year of its effective date, a minimum of 250,000 shares subject to the time-based option will vest. In the event of a Sale Event (as defined in the 2022 Plan), all of the then-outstanding and unvested portions of the time-based option, 50% of the then-outstanding and unvested portions of the performance-based option, and any of the then-outstanding and unvested portions of the stock price-based option for which the applicable stock-price milestone has been satisfied in connection with the Sale Event, will become vested and exercisable. Settlement Agreement with Myeloid In December 2021, we entered into a research collaboration and exclusive option agreement, or the Myeloid Collaboration Agreement, with Myeloid, during which time we and Myeloid had one common board member, Dr. Cahill, who is also an affiliate of Newpath Partners, L.P. and holds more than 30% of Myeloid’s voting securities. In 2023, we terminated the Myeloid Collaboration Agreement. In January 2024, we entered into a settlement agreement, or the Settlement Agreement, with Myeloid resolving two arbitration proceedings. Under the terms of the Settlement Agreement, the parties agreed to resolve and settle all 154 disputes between the parties and release all claims between them relating to the Myeloid Collaboration Agreement and the arbitrations in exchange for our payment to Myeloid of $13.5 million, certain mutual covenants, and other consideration. Accordingly, for the year ended December 31, 2023, we recorded a charge of $13.5 million, and paid the $13.5 million during the year ended December 31, 2024. Indemnification Agreements We have entered into agreements to indemnify our directors and executive officers. These agreements, among other things, require us to indemnify these individuals for certain expenses (including attorneys’ fees), judgments, fines and settlement amounts reasonably incurred by such person in any action or proceeding, including any action by or in our right, on account of any services undertaken by such person on behalf of our company or that person’s status as a member of our board of directors or our executive officer to the maximum extent allowed under Delaware law. Policies for Approval of Related Party Transactions Our board of directors reviews and approves transactions with directors, officers and holders of 5 percent or more of our voting securities and their affiliates, each a related party. The material facts as to the related party’s relationship or interest in the transaction were disclosed to our board of directors prior to their consideration of such transaction, and the transaction was not considered approved by our board of directors unless a majority of the directors who are not interested in the transaction approved the transaction. Further, when stockholders were entitled to vote on a transaction with a related party, the material facts of the related party’s relationship or interest in the transaction were disclosed to the stockholders, who were obligated to approve the transaction in good faith. We adopted a written related party transactions policy that provides that such transactions must be approved by our audit committee. Pursuant to this policy, the audit committee has the primary responsibility for reviewing and approving or disapproving “related party transactions,” which are transactions between us and related persons in which the aggregate amount involved exceeds or may be expected to exceed $120,000 and in which a related person has or will have a direct or indirect material interest. In reviewing any such proposal, our audit committee or other committee of independent directors are to consider the relevant facts of the transaction, including the risks, costs and benefits to us and whether the transaction is on terms no less favorable than terms generally available to an unaffiliated third party under the same or similar circumstances. For purposes of this policy, a related person is defined as a director, executive officer, nominee for director, or greater than 5 percent beneficial owner of our common stock, in each case since the beginning of the most recently completed year, and their immediate family members. Director Independence Our common stock is listed on the Nasdaq Global Market. Under the Nasdaq listing rules, independent directors must comprise a majority of a listed company’s board of directors within twelve months from the date of listing. In addition, the Nasdaq listing rules require that, subject to specified exceptions, each member of a listed company’s audit, compensation and nominating and corporate governance committees be independent within twelve months from the date of listing. Audit committee members must also satisfy additional independence criteria, including those set forth in Rule 10A-3 under the Exchange Act and compensation committee members must also satisfy the independence criteria set forth in Rule 10C-1 under the Exchange Act. Under Nasdaq listing rules, a director will only qualify as an “independent director” if, in the opinion of that company’s board of directors, that person does not have a relationship that would interfere with the exercise of independent judgment in carrying out the responsibilities of a director. In order to be considered independent for purposes of Rule 10A-3 under the Exchange Act, a member of an audit committee of a listed company may not, other than in his or her capacity as a member of the audit committee, the board of directors or any other board committee: (i) accept, directly or indirectly, any consulting, advisory or other compensatory fee from the listed company or any of its subsidiaries, other than compensation for board service; or (ii) be an affiliated person of the listed company or any of its subsidiaries. In order to be considered independent for purposes of Rule 10C-1, the board of directors must consider, for each member of a compensation committee of a listed company, all factors specifically relevant to determining whether a director has a relationship to such company which is material to that director’s ability to be independent from management in connection with the duties of a compensation committee member, including, but not limited to: the source of compensation of the director, including any consulting advisory or other compensatory fee paid by such 155 company to the director, and whether the director is affiliated with the company or any of its subsidiaries or affiliates. In February of 2026, our board of directors undertook a review of the composition of our board of directors and its committees and the independence of each director. Based upon information requested from and provided by each director concerning his or her background, employment and affiliations, including family relationships, our board of directors has determined that all members of our board of directors, except Allan Reine and Jeffrey Marrazzo, are independent directors, including for purposes of Nasdaq and the SEC rules. In making that determination, our board of directors considered the relationships that each director has with us and all other facts and circumstances the board of directors deemed relevant in determining independence, including the potential deemed beneficial ownership of our capital stock by each director, including non-employee directors that are affiliated with certain of our major stockholders. We believe that the composition and functioning of our board of directors and each of our committees complies with all applicable requirements of Nasdaq and the rules and regulations of the SEC. There are no family relationships between or among any of our executive officers and directors. The principal occupation and employment during the past five years of each of our directors was carried on, in each case except as specifically identified, with a corporation or organization that is not a parent, subsidiary or other affiliate of us. There is no arrangement or understanding between any of our directors and any other person or persons pursuant to which he or she is to be selected as a director. There are no material legal proceedings to which any of our directors, executive officers, or affiliates is a party adverse to us or our subsidiary or in which any such person has a material interest adverse to us or our subsidiary. 156 Item 14. Principal Accountant Fees and Services PricewaterhouseCoopers LLP, or PwC, served as independent registered public accounting firm for our Company with respect to the audit of the Company’s consolidated financial statements for the fiscal year ended December 31, 2025 The aggregate fees billed by categories of services are as follows for each of the years ended December 31: Fee Category 2025 2024 Audit Fees (1) $ 970,000 $ 1,092,000 Audit-Related Fees — — Tax Fees — — All Other Fees (2) 2,125 2,125 Total Fees $ 972,125 $ 1,094,125 (1) “Audit Fees” consist of fees billed for professional services performed by PwC for the audit of our annual consolidated financial statements, the review of interim consolidated financial statements, review of the registration statement on Form S-3 and Form S-8, comfort letters issued for financing, and related services that are normally provided in connection with statutory and regulatory filings or engagements. (2) All other fees consist of database subscription fees. Pre-Approval by Audit Committee of Principal Accountant Services Our audit committee (or a subcommittee delegated to it by the audit committee) approves in advance all services proposed to be performed for our Company or its subsidiaries by any independent registered public accounting firm that performs (or proposes to perform) audit, review or attest services for our Company or its subsidiaries. 157 PART IV Item 15. Exhibits and Financial Statement Schedules (1) Financial Statements For a list of the financial statements included herein, see Index to the Consolidated Financial Statements on page F-1 of this Annual Report on Form 10-K, incorporated into this Item by reference. (2) Financial Statement Schedules Schedules have been omitted since they are either not required or not applicable or the information is otherwise included herein. (3) Exhibits Exhibit number Description of exhibit 3.1 Third Amended and Restated Certificate of Incorporation of Prime Medicine, Inc. (incorporated by reference to Exhibit 3.1 to the Registrant’s Current Report on Form 8-K, filed with the SEC on October 24, 2022) 3.2 Certificate of Amendment to Third Amended and Restated Certificate of Incorporation of Prime Medicine, Inc. (incorporated by reference to Exhibit 3.1 to the Registrant’s Current Report on Form 8-K, filed with the SEC on June 12, 2024). 3.3 Second Amended and Restated Bylaws of Prime Medicine, Inc. (incorporated by reference to Exhibit 3.1 to the Registrant’s Current Report on Form 8-K, filed with the SEC on May 21, 2024). 4.1 Amended and Restated Investors’ Rights Agreement among the Registrant and certain of its stockholders, dated April 20, 2021 (incorporated by reference to Exhibit 4.1 of the Registrant’s Registration Statement on Form S-1/A (File No. 333-267579) filed with the SEC on October 17, 2022) 4.2 Form of Common Stock Certificate (incorporated by reference to Exhibit 4.2 of the Registrant’s Registration Statement on Form S-1/A (File No. 333-267579) filed with the SEC on October 17, 2022) 4.3 Description of Securities (incorporated by reference to Exhibit 4.3 of the Registrant’s Annual Report on Form 10-K, filed with the SEC on March 9, 2023) 10.1# 2019 Stock Option and Grant Plan, as amended, and forms of award agreements thereunder (incorporated by reference to Exhibit 10.1 of the Registrant’s Registration Statement on Form S-1/A (File No. 333-267579) filed with the SEC on October 17, 2022) 10.2# 2022 Stock Option and Incentive Plan and forms of award agreements thereunder (incorporated by reference to Exhibit 10.2 of the Registrant’s Registration Statement on Form S-1/A (File No. 333-267579) filed with the SEC on October 17, 2022) 10.3# 2022 Employee Stock Purchase Plan (incorporated by reference to Exhibit 10.3 of the Registrant’s Registration Statement on Form S-1/A (File No. 333-267579) filed with the SEC on October 17, 2022) 10.4# Form of Executive Employment Agreement (incorporated by reference to Exhibit 10.23 of the Registrant’s Registration Statement on Form S-1/A (File No. 333-267579) filed with the SEC on October 17, 2022) 10.5# Senior Executive Cash Incentive Bonus Plan (incorporated by reference to Exhibit 10.4 of the Registrant’s Registration Statement on Form S-1/A (File No. 333-267579) filed with the SEC on October 17, 2022) 10.6# Second Amended and Restated Non-Employee Director Compensation Policy (incorporated by reference to Exhibit 10.1 of the Registrant’s Quarterly Report on Form 10-Q, filed with the SEC on August 7 , 202 5 ) 10.7# Form of Officer Indemnification Agreement (incorporated by reference to Exhibit 10.6 of the Registrant’s Registration Statement on Form S-1/A (File No. 333-267579) filed with the SEC on October 17, 2022) 10.8# Form of Director Indemnification Agreement (incorporated by reference to Exhibit 10.7 of the Registrant’s Registration Statement on Form S-1/A (File No. 333-267579) filed with the SEC on October 17, 2022) 158 Exhibit number Description of exhibit 10.9# Amended and Restated Employment Agreement, dated July 7, 2022, between the Registrant and Keith Gottesdiener (incorporated by reference to Exhibit 10.8 of the Registrant’s Registration Statement on Form S-1/A (File No. 333-267579) filed with the SEC on October 17, 2022) 10.10# Amended and Restated Employment Agreement, dated July 7, 2022, between the Registrant and Carman Alenson (incorporated by reference to Exhibit 10.11 of the Registrant’s Registration Statement on Form S-1/A (File No. 333-267579), filed with the SEC on October 17, 2022) 10.11# Amended and Restated Employment Agreement, dated July 11, 2022, between the Registrant and Ann Lee (incorporated by reference to Exhibit 10.10 of the Registrant’s Registration Statement on Form S-1/A (File No. 333-267579) filed with the SEC on October 17, 2022) 10.12# Amended and Restated Employment Agreement, dated July 20, 2022, between the Registrant and Jeremy Duffield (incorporated by reference to Exhibit 10.9 of the Registrant’s Registration Statement on Form S-1/A (File No. 333-267579) filed with the SEC on October 17, 2022) 10.13# Amendment No. 1 to Amended and Restated Employment Agreement, dated July 6, 2023, between Registrant and Keith Gottesdiener (incorporated by reference to Exhibit 10.1 to the Registrant’s Quarterly Report on Form 10-Q filed with the SEC on November 3, 2023). 10.14# Employment Agreement, effective as of January 17, 2024, between the Registrant and Allan Reine (incorporated by reference to Exhibit 10.1 of the Registrant’s Current Report on Form 8-K filed with the SEC on January 5, 2024) 10.15# Separation Agreement, dated May 18, 2025, between the Registrant and Keith Gottesdiener (incorporated by reference to Exhibit 10.2 of the Registrant’s Quarterly Report on Form 10-Q filed with the SEC on August 7, 2025) 10.16# Consulting Agreement, dated May 18, 2025, between the Registrant and KMG Strategic Consulting LLC (incorporated by reference to Exhibit 10.3 of the Registrant’s Quarterly Report on Form 10-Q filed with the SEC on August 7, 2025) 10.17# Amended and Restated Employment Agreement, effective May 19, 2025, between the Registrant and Allan Reine (incorporated by reference to Exhibit 10.4 of the Registrant’s Quarterly Report on Form 10-Q filed with the SEC on August 7, 2025) 10.18# Consulting Agreement, dated July 15, 2025, between the Registrant and Jeremy Duffield (incorporated by reference to Exhibit 10.6 of the Registrant’s Quarterly Report on Form 10-Q filed with the SEC on August 7, 2025) 10.19# Separation Agreement, dated July 17, 2025, between the Registrant and Jeremy Duffield (incorporated by reference to Exhibit 10.5 of the Registrant’s Quarterly Report on Form 10-Q filed with the SEC on August 7, 2025) 10.20† Collaboration and License Agreement, dated September 26, 2019, between Beam Therapeutics Inc. and the Registrant (incorporated by reference to Exhibit 10.13 of the Registrant’s Registration Statement on Form S-1/A (File No. 333-267579) filed with the SEC on October 17, 2022) 10.21† License Agreement, dated September 26, 2019, between The Broad Institute, Inc. and the Registrant, as amended (incorporated by reference to Exhibit 10.14 of the Registrant’s Registration Statement on Form S-1/A (File No. 333-267579) filed with the SEC on October 17, 2022) 10.22† Amendment No. 1 to License Agreement, dated May 5, 2020, between The Broad Institute, Inc. and the Registrant (incorporated by reference to Exhibit 10.15 of the Registrant’s Registration Statement on Form S-1/A (File No. 333-267579) filed with the SEC on October 17, 2022) 10.23† Amendment No. 2 to License Agreement, dated February 18, 2021, between The Broad Institute, Inc. and the Registrant (incorporated by reference to Exhibit 10.16 of the Registrant’s Registration Statement on Form S-1/A (File No. 333-267579) filed with the SEC on October 17, 2022) 10.24† Amendment No. 3 to License Agreement, dated December 22, 2022, between The Broad Institute, Inc. and the Registrant (incorporated by reference to Exhibit 10.17 of the Registrant’s Annual Report on Form 10-K, filed with the SEC on March 9, 2023) 10.25† Side Letter No. 1 to License Agreement, dated September 27, 2024, between The Broad Institute, Inc. and the Registrant (incorporated by reference to Exhibit 10.3 of the Registrant’s Quarterly Report on Form 10-Q filed with the SEC on November 12, 2024) 10.26† License Agreement, dated December 22, 2022, between The Broad Institute, Inc. and the Registrant (incorporated by reference to Exhibit 10.18 of the Registrant’s Annual Report on Form 10-K, filed with the SEC on March 9, 2023) 159 Exhibit number Description of exhibit 10.27† Pledge from Prime Medicine, amended and restated August 2022, between The Broad Institute, Inc. and the Registrant (incorporated by reference to Exhibit 10.17 of the Registrant’s Registration Statement on Form S-1/A (File No. 333-267579) filed with the SEC on October 17, 2022) 10.28† Amendment No. 4 to License Agreement, dated September 11, 2025, between The Broad Institute, Inc. and the Registrant (incorporated by reference to Exhibit 10. 1 of the Registrant’s Quarterly Reporting on Form 10-Q filed with the SEC on November 7, 2025) 10.29† Amendment No. 5 to License Agreement, dated September 11, 2025, between The Broad Institute, Inc. and the Registrant (incorporated by reference to Exhibit 10. 2 of the Registrant’s Quarterly Reporting on Form 10-Q filed with the SEC on November 7, 2025) 10.30† Side Letter No. 2 to License Agreement, dated September 11, 2025, between The Broad Institute, Inc. and the Registrant (incorporated by reference to Exhibit 10.3 of the Registrant ’ s Quarterly Reporting on Form 10-Q filed with the SEC on November 7, 2025) 10.31 Lease Agreement, dated as of November 22, 2021, between NW Cambridge Property Owner, LLC and the Registrant (incorporated by reference to Exhibit 10.1 of the Registrant’s Quarterly Report on Form 10-Q filed with the SEC on August 7, 2023) 10.32+† Securities Purchase Agreement, dated September 28, 2024, by and between Juno Therapeutics, Inc. and the Registrant (incorporated by reference to Exhibit 10.1 of the Registrant’s Quarterly Report on Form 10-Q, filed with the SEC on November 12, 2024) 10.33+† Research Collaboration and License Agreement, dated September 28, 2024, by and between Juno Therapeutics, Inc. and the Registrant (incorporated by reference to Exhibit 10.2 of the Registrant’s Quarterly Report on Form 10-Q filed with the SEC on November 12, 2024) 19.1*† Prime Medicine, Inc. Second Amended and Restated Insider Trading Policy 21.1* Subsidiaries of the Registrant 23.1* Consent of PricewaterhouseCoopers, LLP, Independent Registered Public Accounting Firm 31.1* Certification of Principal Executive Officer and Prin cipal Financial Officer Pursuant to Rules 13a-14(a) and 15d-14(a) under the Securities Exchange Act of 1934, as Adopted Pursuant to Section 302 of the Sarbanes-Oxley Act of 2002 32.1** Certification of Principal Executive Officer and Principal Financial Officer Pursuant to 18 U.S.C. Section 1350, as Adopted Pursuant to Section 906 of the Sarbanes-Oxley Act of 2002. 97.1 Prime Medicine, Inc. Compensation Recovery Policy, dated September 15, 2023 (incorporated by reference to Exhibit 97.1 of the Registrant’s Annual Report on Form 10-K, filed with the SEC on March 1, 2024) 101.INS* Inline XBRL Instance Document 101.SCH* Inline XBRL Taxonomy Extension Schema Document 101.CAL* Inline XBRL Taxonomy Extension Calculation Linkbase Document 101.DEF* Inline XBRL Taxonomy Extension Definition Linkbase Document 101.LAB* Inline XBRL Taxonomy Extension Label Linkbase Document 101.PRE* Inline XBRL Taxonomy Extension Presentation Linkbase Document 104* Cover Page Interactive Data File (embedded within the Inline XBRL document) __________________ * Filed herewith. ** The certifications furnished in Exhibit 32.1 and Exhibit 32.2 hereto are deemed to accompany this Annual Report on Form 10-K and will not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended. Such certifications will not be deemed to be incorporated by reference into any filings under the Securities Act of 1933, as amended, or the Securities Exchange Act of 1934, as amended, except to the extent that the Registrant specifically incorporates it by reference. # Indicates a management contract or any compensatory plan, contract or arrangement. † Portions of this exhibit (indicated by asterisks) have been omitted pursuant to Item 601(b)(10) of Regulation S-K. + Certain exhibits and schedules to these agreements have been omitted pursuant to Item 601(a)(5) and (6) of Regulation S-K. The registrant will furnish copies of any of the exhibits and schedules to the Securities and Exchange Commission upon request. 160 Item 16. Form 10-K Summary None. 161 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. Prime Medicine, Inc. March 3, 2026 By: /s/ Allan Reine Allan Reine Chief Executive Officer POWER OF ATTORNEY AND SIGNATURES Each person whose individual signature appears below hereby authorizes and appoints Allan Reine and Carman Alenson, and each of them, with full power of substitution and resubstitution and full power to act without the other, as his or her true and lawful attorney-in-fact and agent to act in his or her name, place and stead and to execute in the name and on behalf of each person, individually and in each capacity stated below, and to file any and all amendments to this Annual Report on Form 10-K and to file the same, with all exhibits thereto, and other documents in connection therewith, with the Securities and Exchange Commission, granting unto said attorneys-in-fact and agents, and each of them, full power and authority to do and perform each and every act and thing, ratifying and confirming all that said attorneys-in-fact and agents or any of them or their or his or her substitute or substitutes may lawfully do or cause to be done by virtue thereof. Pursuant to the requirements of the Securities Exchange Act of 1934, this report has been signed below by the following persons on behalf of the registrant and in the capacities and on the dates indicated. Signature Title Date /s/ Allan Reine Chief Financial Officer (Principal Executive Officer and Principal Financial Officer) March 3, 2026 Allan Reine /s/ Carman Alenson Chief Accounting Officer (Principal Accounting Officer) March 3, 2026 Carman Alenson /s/ Thomas Cahill Director March 3, 2026 Thomas Cahill /s/ Wendy Chung Director March 3, 2026 Wendy Chung /s/ Kaye Foster Director March 3, 2026 Kaye Foster /s/ Michael Kelly Director March 3, 2026 Michael Kelly /s/ Jeff Marrazzo Director March 3, 2026 Jeff Marrazzo /s/ Robert Nelsen Director March 3, 2026 Robert Nelsen /s/ David Schenkein Director March 3, 2026 David Schenkein 162 PRIME MEDICINE, INC. INDEX TO CONSOLIDATED FINANCIAL STATEMENTS Page Report of Independent Registered Public Accounting Firm (PCAOB ID: 238 ) F- 2 Consolidated Balance Sheets F- 3 Consolidated Statements of Operations and Comprehensive Loss F- 4 Consolidated Statements of Stockholders’ Equity F- 5 Consolidated Statements of Cash Flows F- 6 Notes to Consolidated Financial Statements F- 8 F-1 REPORT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM To the Board of Directors and Stockholders of Prime Medicine, Inc. Opinion on the Financial Statements We have audited the accompanying consolidated balance sheets of Prime Medicine, Inc. and its subsidiary (the "Company") as of December 31, 2025 and 2024, and the related consolidated statements of operations and comprehensive loss, of stockholders' equity and of cash flows for the years then ended, 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, 2025 and 2024, and the results of its operations and its cash flows for the years then ended in conformity with accounting principles generally accepted in the United States of America. Substantial Doubt About the Company's Ability to Continue as a Going Concern The accompanying consolidated financial statements have been prepared assuming that the Company will continue as a going concern. As discussed in Note 1 to the consolidated financial statements, the Company has incurred recurring losses from operations and has an accumulated deficit, which raises substantial doubt about its ability to continue as a going concern. Management's plans in regard to these matters are also described in Note 1. The consolidated financial statements do not include any adjustments that might result from the outcome of this uncertainty. 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. /s/ PricewaterhouseCoopers LLP Boston, Massachusetts March 3, 2026 We have served as the Company's auditor since 2021. F-2 PRIME MEDICINE, INC. CONSOLIDATED BALANCE SHEETS December 31, (in thousands, except share and per share amounts) 2025 2024 Assets Current assets: Cash and cash equivalents $ 63,032 $ 182,476 Short-term investments 114,648 2,998 Short-term investment — related party — 4,968 Prepaid expenses 2,939 6,777 Other current assets 674 14,667 Total current assets 181,293 211,886 Property and equipment, net 20,572 24,404 Operating lease right-of-use assets 126,177 47,156 Restricted cash 13,691 14,062 Other assets 1,000 — Total assets $ 342,733 $ 297,508 Liabilities and Stockholders’ Equity Current liabilities: Accounts payable $ 8,887 $ 11,351 Accrued expenses and other current liabilities 12,600 15,904 Deferred revenue — related party 7,824 7,092 Operating lease liability 8,137 3,614 Total current liabilities 37,448 37,961 Deferred revenue, net of current — related party 58,127 63,218 Operating lease liability, net of current 108,290 37,180 Research and development funding liability 18,000 6,000 Total liabilities 221,865 144,359 Commitments and contingencies (Note 12) Stockholders’ equity Common stock, par value of $ 0.00001 per share; 775,000,000 shares authorized; 180,514,014 and 131,160,842 shares issued and outstanding as of December 31, 2025 and 2024, respectively 2 2 Additional paid-in capital 1,009,138 840,358 Accumulated other comprehensive income 82 1 Accumulated deficit ( 888,354 ) ( 687,212 ) Total stockholders’ equity 120,868 153,149 Total liabilities and stockholders’ equity $ 342,733 $ 297,508 The accompanying notes are an integral part of these consolidated financial statements. F-3 PRIME MEDICINE, INC. CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS Year Ended December 31, (in thousands, except share and per share amounts) 2025 2024 Revenue: Collaboration revenue — related party $ 4,586 $ 1,609 Collaboration revenue 46 1,374 Total revenue 4,632 2,983 Operating expenses: Research and development 160,636 155,289 General and administrative 52,346 50,161 Total operating expenses 212,982 205,450 Loss from operations ( 208,350 ) ( 202,467 ) Other income: Interest income 4,149 3,522 Accretion (amortization) of investments 2,479 3,507 Change in fair value of short-term investment — related party 432 ( 485 ) Other income, net 148 41 Total other income, net 7,208 6,585 Net loss attributable to common stockholders $ ( 201,142 ) $ ( 195,882 ) Net loss per share attributable to common stockholders, basic and diluted $ ( 1.35 ) $ ( 1.65 ) Weighted-average common shares outstanding, basic and diluted 148,758,527 118,600,381 Comprehensive loss: Net loss $ ( 201,142 ) $ ( 195,882 ) Change in unrealized loss on investments, net of tax 81 16 Comprehensive loss $ ( 201,061 ) $ ( 195,866 ) The accompanying notes are an integral part of these consolidated financial statements. F-4 PRIME MEDICINE, INC. CONSOLIDATED STATEMENTS OF STOCKHOLDERS’ EQUITY Common Stock Additional Paid-in Capital Accumulated Other Comprehensive Income Accumulated Deficit Total Stockholders' Equity (in thousands, except share amounts) Shares Amount Balances at December 31, 2023 97,377,121 $ 2 $ 624,414 $ ( 15 ) $ ( 491,330 ) $ 133,071 Issuance of common stock from public offering, net of issuance costs of $ 8.9 million 22,560,001 — 132,055 — — 132,055 Issuance of pre-funded warrants, net of issuance costs of $ 1.2 million — — 18,800 — — 18,800 Issuance of common stock under the Securities Purchase Agreement to BMS — related party (Note 9) 11,006,163 — 38,081 — — 38,081 Issuances of common stock under the employee stock purchase plan 189,509 — 837 — — 837 Issuances of common stock upon exercise of stock options 28,048 — 103 — — 103 Stock-based compensation expense — — 26,068 — — 26,068 Change in unrealized loss on investments, net of tax — — — 16 — 16 Net loss — — — — ( 195,882 ) ( 195,882 ) Balances at December 31, 2024 131,160,842 $ 2 $ 840,358 $ 1 $ ( 687,212 ) $ 153,149 Issuance of common stock from public offering, net of issuance costs of $ 5.8 million 43,700,000 — 138,390 — — 138,390 Issuance of restricted stock units 2,000,000 — — — — — Exercise of pre-funded warrants 3,199,984 — — — — — Issuance of common stock under the employee stock purchase plan 231,166 — 341 — — 341 Issuance of common stock upon exercise of stock options 222,022 — 781 — — 781 Stock-based compensation expense — — 29,268 — — 29,268 Change in unrealized loss on investments, net of tax — — — 81 — 81 Net loss — — — — ( 201,142 ) ( 201,142 ) Balances at December 31, 2025 180,514,014 $ 2 $ 1,009,138 $ 82 $ ( 888,354 ) $ 120,868 The accompanying notes are an integral part of these consolidated financial statements. F-5 PRIME MEDICINE, INC. CONSOLIDATED STATEMENTS OF CASH FLOWS Year Ended December 31, (in thousands) 2025 2024 Cash flows used in operating activities: Net loss $ ( 201,142 ) $ ( 195,882 ) Adjustments to reconcile net loss to net cash used in operating activities: Stock-based compensation expense 29,268 26,068 Non cash lease expense 9,698 12,355 Depreciation expense 7,321 6,128 Change in fair value of short-term investment — related party ( 432 ) 484 Amortization of premiums and discount on short-term investments ( 1,937 ) ( 3,094 ) Changes in operating assets and liabilities: Prepaid expenses and other current assets 4,545 ( 15,859 ) Accounts payable 996 ( 5,257 ) Accrued expenses and other current liabilities ( 1,160 ) 1,843 Accrued settlement payment — related party — ( 13,500 ) Deferred revenue — related party ( 4,359 ) 70,310 Lease liability ( 5,362 ) ( 6,461 ) Net cash used in operating activities ( 162,564 ) ( 122,865 ) Cash flows (used in) provided by investing activities: Maturities of investments 95,781 204,200 Sales of investments — related party 5,400 — Purchases of investments ( 205,413 ) ( 129,449 ) Purchases of property and equipment ( 4,531 ) ( 7,294 ) Return (payment) of security deposit — 1,000 Net cash (used in) provided by investing activities ( 108,763 ) 68,457 Cash flows provided by financing activities: Proceeds from follow-on offering, net of issuance costs 138,390 132,055 Proceeds from research and development funding liability 12,000 6,000 Net proceeds from stock option exercises 781 103 Proceeds from ESPP offerings 341 837 Proceeds from issuance of common stock under the BMS Securities Purchase Agreement — related party — 38,081 Proceeds from issuance of pre-funded warrants, net of issuance costs — 18,800 Net cash provided by financing activities 151,512 195,876 Net change in cash, cash equivalents, and restricted cash ( 119,815 ) 141,468 Cash, cash equivalents, and restricted cash at beginning of period 196,538 55,070 Cash, cash equivalents, and restricted cash at end of period $ 76,723 $ 196,538 The accompanying notes are an integral part of these consolidated financial statements. F-6 PRIME MEDICINE, INC. CONSOLIDATED STATEMENTS OF CASH FLOWS Year Ended December 31, (in thousands) 2025 2024 Reconciliation of cash, cash equivalents and restricted cash: Cash, cash equivalents, and restricted cash at end of period $ 76,723 $ 196,538 Less: restricted cash 13,691 14,062 Total cash, and cash equivalents $ 63,032 $ 182,476 Supplemental cash flow information: Right-of-use assets obtained in exchange for new operating lease liabilities $ 83,757 $ 44,935 Decrease in right-of-use assets due to lease termination $ 3,120 $ — Increase in right-of-use assets upon settlement with landlord $ 10,911 $ — Supplemental disclosure of non-cash investing and financing activities: Purchases of property and equipment included in accounts payable and accrued expenses $ 114 $ 1,154 The accompanying notes are an integral part of these consolidated financial statements. F-7 PRIME MEDICINE, INC. NOTES TO CONSOLIDATED FINANCIAL STATEMENTS 1. Nature of the Business and Basis of Presentation Prime Medicine, Inc., together with its consolidated subsidiary, or the Company, is a biotechnology company committed to delivering a new class of differentiated one-time curative treatments. The Company is deploying Prime Editing technology, which it believes is a versatile, precise, and efficient gene editing technology. The Company was incorporated in the State of Delaware in September 2019. Its principal offices are in Cambridge, Massachusetts. Liquidity and Capital Resources Since its inception, the Company has devoted substantially all of its resources to building its Prime editing platform and advancing development of its portfolio of programs, establishing and protecting its intellectual property, conducting research and development activities, organizing and staffing the company, business planning, raising capital and providing general and administrative support for these operations. To date, the Company has funded its operations primarily with proceeds from sales of preferred stock, public offerings of its common stock, and through payments from our collaboration partners. In August 2025, the Company issued and sold 43,700,000 shares of its common stock, including 5,700,000 shares pursuant to the exercise of the underwriters’ option to purchase additional shares, at a price to the public of $ 3.30 per share. As a result of the offering, the Company received approximately $ 138.4 million in net proceeds, after deducting underwriting discounts, commissions and offering costs of $ 5.8 million. Since its inception, the Company has incurred substantial losses. As of December 31, 2025, the Company had an accumulated deficit of $ 888.4 million and expects to generate operating losses and negative operating cash flows for the foreseeable future. As of December 31, 2025, the Company maintains cash, cash equivalents, short-term investments, and related party short-term investments of $ 177.7 million. Going Concern In accordance with Accounting Standards Codification, or ASC, 205-40, Going Concern , or ASC 205-40, the Company evaluated whether there are conditions and events, considered in the aggregate, that raise substantial doubt about the Company’s ability to continue as a going concern within one year after the date on which this Annual Report on Form 10-K is filed. Based on the Company's cash, cash equivalents, and short-term investments as of December 31, 2025, the Company's current and forecasted level of operations, and its forecasted cash flows, the Company’s ability to continue as a going concern is dependent upon its ability to obtain the necessary financing to meet its obligations and repay its liabilities arising from normal business operations when they come due. Management plans to provide for the Company’s capital requirements through financing or other transactions, and selling shares under the Company's “at the market offering” program. There can be no assurance that the Company will be able to raise additional capital to fund operations with terms acceptable to the Company, or at all. Because certain elements of management’s plans to mitigate the conditions that raised substantial doubt about the Company’s ability to continue as a going concern are outside of the Company’s control, including the ability to raise capital through an equity or other financing, those elements cannot be considered probable according to ASC 205-40, and therefore cannot be considered in the evaluation of mitigating factors. As a result, management has concluded that substantial doubt exists about the Company’s ability to continue as a going concern for 12 months from the date these consolidated financial statements are issued. The consolidated financial statements as of December 31, 2025 have been prepared under the assumption that the Company will continue as a going concern for the next 12 months and that contemplates the realization of assets and satisfaction of liabilities and commitments in the normal course of business. The Company’s ability to continue as a going concern is dependent upon its uncertain ability to obtain additional capital, reduce expenditures and/or execute on its business plan. These consolidated financial statements do not include any adjustments that might result from the outcome of this uncertainty. F-8 Risks and Uncertainties The Company is subject to risks and uncertainties common to early stage companies in the biotechnology industry, including, but not limited to, completing preclinical studies and clinical trials, obtaining regulatory approval for product candidates, market acceptance of products, development by competitors of new technological innovations, dependence on key personnel, the ability to attract and retain qualified employees, reliance on third-party organizations, protection of proprietary technology, compliance with government regulations, and the ability to raise additional capital to fund operations. The Company’s 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. These efforts require significant amounts of additional capital, adequate personnel and infrastructure, and extensive compliance-reporting capabilities. Even if the Company’s development efforts are successful, it is uncertain when, if ever, the Company will realize significant revenue from product sales. The Company will need to raise additional capital to support its continuing operations and to pursue its growth strategy. Until such time as the Company can generate significant revenue from product sales, if ever, it expects to finance its operations through a combination of private and public equity offerings, debt financings, collaborations, strategic alliances, licensing or other arrangements with third parties, or other similar transactions. The Company may be unable to raise additional capital or enter into such other agreements when needed on favorable terms or at all. The inability to raise capital as and when needed would have a negative impact on the Company’s financial condition and its ability to pursue its business strategy. The Company will need to generate significant revenue to achieve profitability, and it may never do so. Basis of Presentation The accompanying consolidated financial statements reflect the operations of the Company and its wholly-owned subsidiary. Intercompany balances and transactions have been eliminated in consolidation. The accompanying consolidated financial statements have been prepared in conformity with generally accepted accounting principles in the United States of America, or GAAP. Any reference in these notes to applicable guidance is meant to refer to the authoritative GAAP as found in the ASC and Accounting Standards Updates, or ASU of the Financial Accounting Standards Board, or FASB. Principles of Consolidation The Company’s consolidated financial statements include the accounts of Prime Medicine, Inc. and its wholly owned subsidiary, Prime Medicine Securities Corp., a Massachusetts securities corporation. All significant intercompany balances and transactions have been eliminated in consolidation. 2. Summary of Significant Accounting Policies Use of Estimates The preparation of the Company’s consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and 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 within these consolidated financial statements include, but are not limited to, the valuation of the Company’s stock-based awards. The Company bases its estimates on historical experience, known trends and other market-specific or other relevant factors that it believes to be reasonable under the circumstances. On an ongoing basis, management evaluates its estimates, as there are changes in circumstances, facts and experience. Actual results may differ materially from those estimates or assumptions. Concentrations of Credit Risk Financial instruments that potentially expose the Company to concentrations of credit risk consist primarily of cash and cash equivalents, short-term investments, and restricted cash. Under its investment policy, the Company invests in U.S. Treasury, government securities, and corporate debt and maintains its cash and cash equivalents at high- F-9 quality and accredited financial institutions in amounts that could exceed federally insured limits. Cash equivalents are invested in money market funds. However, the Company does not believe that it is subject to unusual credit risk beyond the normal credit risk associated with commercial banking relationships. Cash and Cash Equivalents The Company considers all highly liquid investments with an original maturity of three months or less at the time of initial purchase to be cash equivalents. Restricted Cash Restricted cash consists of letters of credit that are required to be maintained in connection with the Company’s lease arrangements. Short-term Investments and Related Party Short-Term Investment The Company’s short-term investments consist of investments in securities with remaining maturities beyond three months at the date of purchase and one year or less from the balance sheet date. The Company classifies its investments as available-for-sale and carries them at fair market value. The unrealized losses on the Company’s available-for-sale debt securities are recorded in other comprehensive loss in the consolidated statements of operations and comprehensive loss. Short-term debt securities are considered impaired when a decline in fair value is judged to be other-than-temporary. The Company consults with its investment managers and considers available quantitative and qualitative evidence in evaluating potential impairment of its short-term investments on a quarterly basis. If the cost of an individual investment exceeds its fair value, the Company evaluates, among other factors, general market conditions, the duration and extent to which the fair value is less than cost and its intent and ability to hold the investment. Once a decline in fair value is determined to be other-than-temporary, an impairment charge will be recorded to other income (expense), net, in the consolidated statements of operations and comprehensive loss. The Company’s short-term investment — related party was obtained from the collaboration agreement with Beam Therapeutics, Inc., or Beam, which is a public company trading on the Nasdaq Exchange. At each reporting date, the Company recognizes the fair value of the short-term investment — related party on the consolidated balance sheets. Unrealized and realized gains and losses on the Company’s equity investment is included as a component of other income (expense) in the consolidated statements of operations and comprehensive loss. The costs of debt and equity securities for purposes of computing realized and unrealized gains and losses is based on the specific identification method. 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 that are significant to determining the fair value of the assets or liabilities, including pricing models, discounted cash flow methodologies and similar techniques. F-10 The Company’s cash equivalents and short-term investments are carried at fair value, determined according to the fair value hierarchy described above. The carrying values of the Company’s accounts payable and accrued expenses approximate their fair values due to the short-term nature of these liabilities. Property and Equipment Property and equipment are stated at cost less accumulated depreciation. Depreciation expense is recognized using the straight-line method over the estimated useful life of each asset as follows: Asset Class Estimated Useful Life Laboratory equipment 5 years Furniture and fixtures 5 years Computer hardware and software 3 years Leasehold improvements Shorter of remaining lease term or useful life Costs for capital assets not yet placed into service are capitalized and are depreciated once placed into service. Upon retirement or sale, the cost of assets disposed of and the related accumulated depreciation and amortization are removed from the accounts and any resulting gain or loss is included in loss from operations. Expenditures for repairs and maintenance that do not improve or extend the life of the respective assets are charged to expense as incurred. Leases The Company accounts for leases in accordance with ASC 842, Leases . In accordance with ASC 842, the Company determines if an arrangement is or contains a lease at inception. A contract is or contains a lease if the contract conveys the right to control the use of an identified asset for a period of time in exchange for consideration. The Company classifies leases at the lease commencement date as operating or finance leases and records a right-of-use asset and a lease liability on the consolidated balance sheet for all leases with an initial lease term of greater than 12 months. Leases with an initial term of 12 months or less are not recorded in the balance sheet, but payments are recognized as expense on a straight-line basis over the lease term. The Company has elected not to recognize leases with terms of 12 months or less. A lease qualifies as a finance lease if any of the following criteria are met at the inception of the lease: (i) there is a transfer of ownership of the leased asset to the Company by the end of the lease term, (ii) the Company holds an option to purchase the leased asset that it is reasonably certain to exercise, (iii) the lease term is for a major part of the remaining economic life of the leased asset, (iv) the present value of the sum of lease payments equals or exceeds substantially all of the fair value of the leased asset, or (v) the nature of the leased asset is specialized to the point that it is expected to provide the lessor no alternative use at the end of the lease term. All other leases are recorded as operating leases. The Company enters into contracts that contain both lease and non-lease components. Non-lease components may include maintenance, utilities, and other operating costs. The Company combines the lease and non-lease components of fixed costs in its lease arrangements as a single lease component. Variable costs, such as utilities or maintenance costs, are not included in the measurement of right-of-use assets and lease liabilities, but rather are expensed when the event determining the amount of variable consideration to be paid occurs. Finance and operating lease assets and liabilities are recognized at the lease commencement date based on the present value of the lease payments over the lease term using the discount rate implicit in the lease. If the rate implicit is not readily determinable, the Company utilizes an estimate of its incremental borrowing rate based upon the available information at the lease commencement date. Operating lease assets are further adjusted for prepaid or accrued lease payments. Operating lease payments are expensed using the straight-line method as an operating expense over the lease term. Certain of the Company’s leases include options to extend or terminate the lease. The amounts determined for the Company’s right-of-use assets and lease liabilities generally do not assume that renewal options or early-termination provisions, if any, are exercised, unless it is reasonably certain that the Company will exercise such options. If initially determined that it is not reasonably certain but subsequently the Company F-11 determines that it is reasonably certain to exercise its renewal options or early-termination provisions, the Company would reassess the lease classification, remeasure the lease liability, and adjust the right-of-use asset. In addition to evaluating arrangement that are leases, the Company examines other contracts with suppliers, vendors and outside parties to identify whether such contracts contain an embedded lease and, as applicable, records such embedded leases in accordance with ASC 842. Impairment of Long-Lived Assets Long-lived assets consist primarily of property and equipment, and operating lease 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 group for recoverability, the Company compares forecasts of undiscounted cash flows expected to result from the use and eventual disposition of the long-lived asset group to its carrying value. An impairment loss would be recognized in loss from operations when estimated undiscounted future cash flows expected to result from the use of an asset group are less than its carrying amount. If such asset group is considered to be impaired, the impairment loss to be recognized is measured based on the excess of the carrying value of the impaired asset group over its fair value. Revenue recognition The Company recognizes revenue in accordance with ASC Topic 606, Revenue from Contracts with Customers . This standard applies to all contracts with customers, except for contracts that are within the scope of other standards. Under ASC 606, an entity recognizes revenue when its customer obtains control of promised goods or services, in an amount that reflects the consideration which the entity expects to receive in exchange for those goods or services. The Company enters into collaboration and licensing agreements with partners under which it may exclusively license rights to research, develop, manufacture, and commercialize product candidates to third parties. The terms of these arrangements typically include payment to the Company of one or more of the following: (1) non-refundable, upfront fees; (2) equity investment; (3) reimbursement of certain costs; (4) customer option fees for additional goods or services; (5) milestone payments; and (6) royalties on net sales of licensed products. In determining the appropriate amount of revenue to be recognized as it fulfills its obligations under each of its agreements, the Company performs the following steps: (i) identification of the promised goods or services in the contract; (ii) determination of whether the promised goods or services are performance obligations including whether they are distinct in the context of the contract; (iii) measurement of the transaction price, including the constraint on variable consideration; (iv) allocation of the transaction price to the performance obligations; and (v) recognition of revenue when (or as) the Company satisfies each performance obligation. As part of the accounting for these arrangements, the Company must use its judgment to determine: (a) the number of performance obligations based on the determination under step (ii) above; (b) the transaction price under step (iii) above; (c) the stand-alone selling price for each performance obligation identified in the contract for the allocation of transaction price in step (iv) above; and (d) the contract term and pattern of satisfaction of the performance obligations under step (v) above. The Company also uses judgment to determine whether milestones or other variable consideration, except for royalties, should be included in the transaction price as described further below. The transaction price is allocated to each performance obligation on a relative stand-alone selling price basis, for which the Company recognizes revenue as or when the performance obligations under the contract are satisfied. The Company evaluates the measure of progress each reporting period and, if necessary, adjusts the measure of performance and related revenue recognition. Amounts due to the Company for satisfying the revenue recognition criteria or that are contractually due based upon the terms of the collaboration agreements are recorded as collaboration receivable in the Company’s consolidated balance sheet. Amounts received prior to satisfying the revenue recognition criteria are recorded as deferred revenue F-12 in the Company’s consolidated balance sheets. Deferred revenue expected to be recognized as revenue within 12 months following the balance sheet date are classified as current deferred revenue. Amounts not expected to be recognized as revenue within the 12 months following the balance sheet date are classified as deferred revenue, net of current. Milestone payments At the inception of each arrangement that includes milestone payments, the Company evaluates whether the milestones are considered probable of being achieved and estimates the amount to be included in the transaction price using the most likely amount method. If it is probable that a significant revenue reversal would not occur, the associated milestone value is included in the transaction price. Milestone payments that are not within the control of the Company or the licensee, such as regulatory approvals, are not considered probable of being achieved until those approvals are received. The Company evaluates factors such as the scientific, clinical, regulatory, commercial and other risks that must be overcome to achieve the particular milestone in making this assessment. There is considerable judgment involved in determining whether it is probable that a significant revenue reversal would not occur. At the end of each subsequent reporting period, the Company reevaluates the probability of achievement of all milestones subject to constraint and, if necessary, adjusts its estimate of the overall transaction price. Any such adjustments are recorded on a cumulative catch-up basis, which would affect revenues and earnings in the period of adjustment. Research and Development Expenses Research and development expenses are expensed as incurred. Research and development expenses may consist of costs incurred in connection with acquired in-process research and development and performing research and development activities, including amounts incurred under agreements with external vendors and consultants engaged to perform preclinical studies and to manufacture research and development materials for use in such studies, salaries and related personnel costs, stock-based compensation, consultant fees, and third-party license fees. Upfront payments payable by the Company under license agreements are expensed upon receipt of the license, and annual maintenance fees under license agreements are expensed over the maintenance period. Milestone payments payable by the Company under license agreements are accrued, with a corresponding expense being recognized, in the period in which the milestone is determined to be probable of achievement and the related amount is reasonably estimable. Nonrefundable advance payments made by the Company for goods or services to be received in the future for use in research and development activities are recorded as prepaid expenses. The prepaid amounts are expensed as the related goods are delivered or the services are performed. Acquired In-Process Research and Development The Company measures and recognizes asset acquisitions or licenses to intellectual property that are not deemed to be business combinations based on the cost to acquire or license the asset or group of assets, which includes transaction costs. Goodwill is not recognized in asset acquisitions or transactions to license intellectual property. In an asset acquisition or license to intellectual property, the cost allocated to acquire in-process research and development with no alternative future use is recognized as research and development expense on the acquisition date. Upfront and milestone payments made are accrued for and expensed when the achievement of the milestone is probable up to the point of regulatory approval. Milestone payments made upon regulatory approval are capitalized and amortized over the remaining useful life of the related product. Patent Costs The Company expenses all patent-related costs incurred in connection with filing and prosecuting patent applications in the period incurred due to the uncertainty about the recovery of the expenditure. Amounts incurred are classified as general and administrative expenses in the statements of operations and comprehensive loss. F-13 Contingencies The Company is subject to contingent liabilities, such as legal proceedings and claims, that arise in the ordinary course of business activities. The Company accrues for loss contingencies when losses become probable and are reasonably estimable. If the reasonable estimate of the loss is a range and no amount within the range is a better estimate, the minimum amount of the range is recorded as a liability on the consolidated balance sheets. The Company does not accrue for contingent losses that, in its judgment, are considered to be reasonably possible, but not probable; however, it discloses the range of reasonably possible losses. Stock-Based Compensation The Company measures stock-based awards granted to employees, directors and non-employees based on the fair value of the awards on the date of grant using the Black-Scholes option-pricing model. The Black-Scholes option pricing model estimates the fair value of the equity award using the expected term, expected volatility, risk-free interest rate, dividend rate, and the fair value of the common stock underlying the stock-based award. The Company estimates the expected life of stock options using the “simplified” method, whereby, the expected life equals the arithmetic average of the vesting term and the original contractual term of the option. Due to the lack of sufficient company-specific historical and implied volatility data, the Company has based its computation of expected volatility on the historical volatility of a representative group of public companies with similar characteristics to the Company, including stage of product development and life science industry focus. The risk-free interest rates for periods within the expected life of the option were based on the U.S. Treasury yield curve in effect during the period the options were granted. The expected dividend yield is assumed to be zero as the Company has never paid dividends and has no current plans to pay any dividends on its common stock. The Company recognizes forfeitures as they occur. The fair value of the common stock underlying shared based awards is the quoted market price of the Company’s common stock on the date of the grant. The Company recognizes stock-based compensation expense on a straight-line basis over the requisite service period of the awards for service-based awards, which is generally the vesting period. Stock-based compensation expense is classified in the consolidated statements 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. Warrants Management assesses warrants under ASC 480, Distinguishing Liabilities from Equity , to determine whether they should be classified as equity or liability. If the classification is determined to be equity, proceeds received for the warrants are recorded as an increase to additional paid-in capital in the consolidated balance sheets. If classified as a liability, the Company records the warrant as a liability on its consolidated balance sheet and remeasures this liability to fair value at each reporting date and recognizes changes in the fair value of the warrant liability as a component of other expense in the consolidated statements of operations and comprehensive loss. Comprehensive Loss Comprehensive loss includes net loss as well as other changes in stockholders’ equity that result from transactions and economic events other than those with stockholders. The Company’s only element of other comprehensive loss is unrealized gains and losses on marketable securities. Net Loss per Share Attributable to Common Stockholders The Company applies the two-class method when computing net loss per share attributable to common stockholders as the Company has issued shares that meet the definition of participating securities. The two-class method determines net loss per share for each class of common and participating securities according to dividends declared or accumulated and participation rights in undistributed earnings. The two-class method requires loss available to common stockholders for the period to be allocated between common and participating securities based upon their respective rights to share in the undistributed earnings as if all loss for the period had been distributed. There is no F-14 allocation required under the two-class method during periods of loss since the participating securities do not have a contractual obligation to share in the losses of the Company. The Company has no participating securities outstanding. 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 common shares outstanding for the period, excluding potentially dilutive common shares and of unvested restricted common stock. Diluted net loss per share 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. 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. In periods in which the Company reports a net loss attributable to common stockholders, diluted net loss per share attributable to common stockholders is generally the same as basic net loss per share attributable to common stockholders since dilutive common shares are not assumed to have been issued if their effect is anti-dilutive. 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 tax assets and liabilities are determined based on the differences between the financial statement basis and tax basis of assets and liabilities using enacted tax rates in effect for 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 the deferred tax assets will not be realized, a valuation allowance is established through a charge to income tax expense. Potential for recovery of deferred tax assets is evaluated by estimating the future taxable profits expected and considering prudent and feasible tax planning strategies. 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 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 percent 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 as well as the related net interest and penalties. Segment Information Under ASC 280, Segment Reporting , operating segment is a component of a public entity that 1) engages in business activities from which it may recognize revenues and incur expenses, 2) its operating results are regularly reviewed by the entity’s chief operating decision maker, or CODM, to make decisions about resource allocation or performance assessment, and 3) its discrete financial information is available. The Company operates and manages its business as a single segment for the purposes of assessing performance and making operating decisions. Our chief executive officer, who is the CODM, manages and allocates resources to the operations of our company on a total company basis by assessing the overall level of resources available and how to best deploy these resources across functions and research and development projects that are in line with our long-term company-wide strategic goals. In making these decisions, the CODM uses consolidated financial information for purposes of evaluating performance, forecasting future period financial results, allocating resources and setting incentive targets. The CODM performs this assessment based on the Company’s consolidated net loss. Through this analysis, the CODM assesses performance by comparing actual net loss verses the budget, and then decides how to allocate resources to invest in the Company’s research and development programs. The measure of segment assets is reported on the consolidated balance sheets as total assets. F-15 The following table contains additional information on our consolidated net loss, including significant segment expenses: Year Ended December 31, (in thousands) 2025 2024 Total revenue $ 4,632 $ 2,983 Operating expenses: Research and development expenses Personnel expenses 50,661 59,988 Facility related 46,506 35,509 Research costs 35,453 41,678 General and administrative expenses: Personnel expenses 23,026 26,569 Other segment items (1) 57,336 41,706 Total operating expenses 212,982 205,450 Total other income, net 7,208 6,585 Net loss $ ( 201,142 ) $ ( 195,882 ) (1) Other segment items consist of professional and consultant fees, license and intellectual property fees, clinical expense, and general and administrative facility costs. Recently Issued Accounting Pronouncements In December 2023, the FASB issued ASU, 2023-09, Income Taxes (Topics 740): Improvements to Income Tax Disclosures , to expand the disclosure requirements for income taxes. Upon adoption, companies will be required to disclose additional specified categories in the rate reconciliation. Companies will also be required to disclose the amount of income taxes paid disaggregated by jurisdiction, among other disclosure requirements. The standard is effective for annual periods beginning after December 15, 2024, and can be applied either prospectively or retrospectively. The Company adopted the standard during the year ended December 31, 2025 and have included required disclosures in Note 11, Income Taxes . In November 2024, the FASB issued ASU 2024-03, Disaggregation of Income Statement Expenses , and in January 2025, issued ASU 2025-01, Clarifying the Effective Date , which requires more detailed information about specified categories of expenses included in certain expense captions presented on the face of the income statement. This ASU is effective for the first annual reporting period beginning after December 15, 2026, and for interim reporting periods within annual reporting periods beginning after December 15, 2027. Early adoption is permitted. The amendments may be applied either (1) prospectively to financial statements issued for reporting periods after the effective date of this ASU or (2) retrospectively to all prior periods presented in the financial statements. The Company is currently evaluating the impact this ASU will have on its disclosures. In September 2025, the FASB issued ASU No. 2025-07, Derivatives and Hedging (Topic 815) and Revenue from Contracts with Customers (Topic 606): Derivatives Scope Refinements and Scope Clarification for Share-Based Noncash Consideration from a Customer in a Revenue Contract . This update introduces a scope exception to derivative accounting for certain contracts with underlyings tied to operations or activities specific to one of the parties. Additionally, the update clarifies that share-based noncash consideration received from a customer should be accounted for under Topic 606 until the right to receive or retain the consideration becomes unconditional. The amendments can be applied prospectively or modified retrospectively and are effective for annual and interim periods beginning after December 15, 2026. The Company is currently evaluating the impact to the Company’s consolidated financial statements. In December 2025, the FASB issue ASU No. 2025-11, Interim Reporting (Topic 270): Narrow-scope Improvements , which improves the navigability of interim reporting guidance. The ASU also addresses the form and content of financial statements, adds lists to ASC 270 of the interim disclosures required by all other codification topics, and establishes a principle under which an entity must “disclose events since the end of the last annual F-16 reporting period that have a material impact on the entity.” This ASU is effective for interim reporting periods within annual reporting periods beginning after December 15, 2027, with early adoption permitted. The Company is currently evaluating the impact this ASU will have on its interim disclosures. Other accounting standards that have been issued by the FASB or other standards-setting bodies that do not require adoption until a future date are not expected to have a material impact on the Company’s financial statements upon adoption. 3. Fair Value Measurements The following tables present the Company’s fair value hierarchy for its assets that are measured at fair value on a recurring basis and indicate the level of the fair value hierarchy utilized to determine such fair value: December 31, 2025 (in thousands) Level 1 Level 2 Level 3 Total Cash equivalents: Money market funds $ — $ 57,282 $ — $ 57,282 U.S. Treasury and government securities — 2,739 — 2,739 Corporate debt securities — 2,698 — 2,698 Short-term investments: U.S. Treasury and government securities — 78,152 — 78,152 Corporate debt securities — 36,496 — 36,496 Total cash equivalents and investments $ — $ 177,367 $ — $ 177,367 December 31, 2024 (in thousands) Level 1 Level 2 Level 3 Total Cash equivalents: Money market funds $ — $ 178,212 $ — $ 178,212 Corporate debt securities — 3,793 — 3,793 Short-term investment: U.S. Treasury and government securities — 2,998 — 2,998 Related party short-term investment: Beam equity securities 4,968 — — 4,968 Total cash equivalents and investments $ 4,968 $ 185,003 $ — $ 189,971 The Company classifies its investments as short-term based on each instrument’s underlying contractual maturity date. The fair value of investments classified as Level 2 are valued using observable inputs to quoted market prices, benchmark yields, reported trades, broker/dealer quotes or alternative pricing sources with reasonable levels of price transparency. Investments in Debt Securities Unrealized gains and losses of investments in debt securities consisted of the following: December 31, 2025 (in thousands) Amortized Cost Unrealized Gains Unrealized Losses Fair Value Short-term investments in debt securities: U.S. Treasury and government securities $ 78,074 $ 78 $ — $ 78,152 Corporate debt securities 36,492 7 ( 3 ) $ 36,496 Total short-term investments in debt securities $ 114,566 $ 85 $ ( 3 ) $ 114,648 F-17 December 31, 2024 (in thousands) Amortized Cost Unrealized Gains Unrealized Losses Fair Value Short-term investments in debt securities: U.S. Treasury and government securities $ 2,997 $ 1 $ — $ 2,998 The contractual maturities of the Company’s investments in debt securities held were as follows: (in thousands) December 31, 2025 December 31, 2024 Due within one year $ 114,648 $ 2,998 Marketable securities in unrealized loss positions consisted of the following: As of December 31, 2025: (in thousands, except number of securities) Number of Securities Fair Value Gross Unrealized Losses Investments in continuous loss position for less than 12 months: Corporate debt securities 8 8,446 ( 3 ) Based on factors such as historical experience, market data, issuer-specific factors, and current economic conditions, the Company did not record an allowance for credit losses as of December 31, 2025 related to these investments. Further, given the lack of significant change in the credit risk, the Company does not consider these investments to be impaired. 4. Property and Equipment, Net Property and equipment, net consisted of the following: December 31, (in thousands) 2025 2024 Property and equipment: Laboratory equipment $ 29,744 $ 27,343 Leasehold improvement 7,911 5,136 Furniture and fixture 1,864 1,075 Computer hardware and software 1,122 869 Construction in progress 365 3,578 Total property and equipment 41,006 38,001 Less: Accumulated depreciation ( 20,434 ) ( 13,597 ) Total property and equipment, net $ 20,572 $ 24,404 Depreciation expense related to property and equipment is as follows: Year ended December 31, (in thousands) 2025 2024 Depreciation expense $ 7,321 $ 6,128 F-18 5. Accrued Expenses and Other Current Liabilities Accrued expenses and other current liabilities consisted of the following: December 31, (in thousands) 2025 2024 Accrued expenses and other current liabilities Employee compensation and benefits $ 7,337 $ 8,976 License fee 1,562 1,938 Research and clinical costs 1,997 907 Facility related — 2,811 Other 1,704 1,272 Total accrued expenses and other current liabilities $ 12,600 $ 15,904 6. Leases 64 Sidney Street, Cambridge, Massachusetts Lease In July 2021, the Company entered into a non-cancelable operating lease to sublease office space located at 64 Sidney Street, Cambridge, Massachusetts . The lease commenced in April 2022 and contained escalating monthly rental payments. The lease term expired in April 2025. The lease required the Company to share in prorated expenses and property taxes based on actual amounts incurred . 60 First Street, Cambridge, Massachusetts Lease In November 2021, the Company entered into a lease for three floors of office and laboratory space at 60 First Street, Cambridge, Massachusetts, with rent commencing in March 2024, subject to any credits pursuant to the terms of the lease, or the 60 First Street Lease. Subsequent to the initial non-cancelable term of the lease of ten years , the Company has an option to extend the lease for an additional period of ten years with the rent during the extension term being the then fair market rent. The Company secured the lease with a $ 13.1 million security deposit, which was recorded as restricted cash on the consolidated balance sheets as of December 31, 2025 and 2024. Accounting Considerations The Company determined that the lease contained three separate lease components, each of which represents a right of use that the Company can benefit from on its own and are neither highly dependent nor highly related to each other. The Company allocated the consideration among the three lease components based on their relative fair market values. In accordance with ASC 842, the lease commenced for one of the lease components in March 2024 and the Company recorded a right-of-use asset of $ 44.9 million, and a corresponding lease liability of $ 33.6 million on the lease commencement date; this includes a reclass of $ 11.3 million from prepaid expenses to right-of-use asset related to build out costs which were determined to be owned by the lessor. In March 2025, the Company determined that the lease commenced on the remaining two lease components and recorded right-of-use assets of $ 76.8 million, and a corresponding lease liability of $ 78.6 million on the lease commencement date. As the exercise of the option to extend the lease term is not reasonably certain, the Company will recognize lease expense for this lease component through February 2034. In June 2024, the Company filed a complaint in Massachusetts Superior Court against NW Cambridge Property Owner, LLC, or NWC, the Company’s landlord at 60 First Street. While the lawsuit was pending, the Company continued to make the disputed payments under the 60 First Street Lease under protest. The disputed payments were recorded within other current assets on the Company’s consolidated balance sheets and was $ 10.8 million as of and December 31, 2024. In November 2025, the Company entered into a settlement agreement with NWC. Under the terms of the settlement agreement, the parties agreed to resolve and settle the lawsuit and release all claims between them relating to the F-19 disputed payments. As a result of the settlement, the Company reclassified $ 10.9 million of the disputed payments to right-of-use asset. This amount will be amortized over the remaining lease term of the 60 First Street Lease. Arsenal Street, Watertown, Massachusetts Lease In August 2024, the Company entered into the third amendment to its existing lease for approximately 16,000 square feet of combined laboratory and office space at 480 Arsenal Street, Watertown Massachusetts, or the 480 Arsenal Amendment. In September 2024, the Company entered into a new lease for approximately 48,500 square feet of combined laboratory and office space at 500 Arsenal Street, Watertown, Massachusetts, or the 500 Arsenal Lease. The landlords of the spaces at 480 Arsenal Street and 500 Arsenal Street are affiliates. The 480 Arsenal Amendment provides the Company with an additional 9,400 square feet of combined laboratory and office space, or the Expansion Space, at no additional cost and also provides an early termination date for the existing space and the Expansion Space. The lease for space at 480 Arsenal Street, including the Expansion Space, terminated on April 30, 2025. The 500 Arsenal Lease term commenced in December 2024 with a base term of 11 months. In December 2024, the Company began constructing improvements to the space, the construction for which was completed in 2025. Subsequent to the base term, the Company has an option to extend the lease through August 2028, which it exercised in February 2025. The Company secured the lease with a $ 0.6 million security deposit, which was recorded as restricted cash on the consolidated balance sheets as of December 31, 2025 and 2024. The 500 Arsenal Lease also provides a tenant improvement allowance of $ 2.4 million and an additional tenant improvement allowance of $ 1.2 million, which the Company would be obligated to repay to the landlord. The Company did not use the additional tenant improvement allowance. Accounting Considerations As the 480 Arsenal Amendment and the 500 Arsenal Lease met the criteria for combining contracts under ASC 842, the Company determined that both 480 Arsenal Amendment and the 500 Arsenal Lease are modifications to its existing lease at 480 Arsenal Street. Within the combined contract the Company identified two separate lease components, each of which represents a right of use that the Company can benefit from on its own and which are neither highly dependent nor highly related to the other. The Company allocated the consideration under the combined contract among the two lease components based on their relative fair market value. In calculating the allocable consideration and the fair market value of each lease component, the Company determined it is probable that it will exercise the option to extend the lease term provided under the 500 Arsenal Lease. In accordance with ASC 842, the Company possessed the ability to control and derive the economic benefit for its leased space at 480 Arsenal on the effective date of the modification. Therefore, on the effective date, the Company recorded a right-of-use asset and a corresponding lease liability, which were not materially different from the existing right-of-use asset and lease liability as of the modification date. For accounting purposes, as the construction of the lessor assets were completed, the Company determined that the 500 Arsenal Lease commenced in March 2025 and recorded right-of-use assets of $ 7.0 million, and a corresponding lease liability of $ 5.5 million on the lease commencement date. Concurrently, the Company also determined that the termination of its leased space at 480 Arsenal Street was reasonably certain, and the Company recorded a $ 3.1 million reduction to the Company’s operating lease liability and its operating lease right-of-use asset on the consolidated balance sheet. Summary of lease costs recognized The following tables contains a summary of the lease costs recognized under ASC 842 and other information pertaining to the Company’s operating leases for the years ended December 31, 2025 and 2024 . F-20 The components of lease cost were as follows: Year Ended December 31, (in thousands) 2025 2024 Lease cost: Operating lease cost $ 22,956 $ 15,175 Variable lease cost 9,454 5,716 Short-term lease cost 1,797 3,512 Sublease income ( 212 ) ( 168 ) Total lease cost $ 33,995 $ 24,235 The weighted-average remaining lease term and discount rate were as follows: December 31, 2025 2024 Weighted average remaining lease term (in years) 7.9 years 8.4 years Weighted average discount rate 12.24 % 12.83 % Future annual lease payments under non-cancelable operating leases as of December 31, 2025 w ere as follows: (in thousands) Undiscounted Amounts Undiscounted lease payments: 2026 $ 21,703 2027 22,355 2028 22,294 2029 21,478 2030 22,123 Thereafter 74,478 Total undiscounted lease payments 184,431 Less: imputed interest ( 68,004 ) Total operating lease liability $ 116,427 7. Stockholder’s Equity Common Stock Under the Third Amended and Restated of Certificate of Incorporation, the Company’s common stock had a par value of $ 0.0001 and each share of common stock entitles the holder to one vote on all matters submitted to the stockholders for a vote. The holders of common stock are entitled to receive dividends, if any, as declared by the Company’s board of directors. Pre-funded Warrants In February 2024, the Company sold pre-funded warrants to purchase 3,200,005 shares of common stock at a public offering price of $ 6.24999 per pre-funded warrant, which represents the per share public offering price of each share of common stock less the $ 0.00001 per share exercise price for each pre-funded warrant. Subject to certain requirements, the pre-funded warrants can be exercised by the holder at any time. In May 2025, the holder exercised all 3,200,005 of its pre-funded warrants on a cashless basis and received 3,199,984 shares of the Company’s common stock. Following this exercise, the Company has no pre-funded warrants outstanding. F-21 The pre-funded warrants met the definition of an equity instrument under ASC 815-40 and funds received were recorded as an increase in additional paid-in capital in the consolidated balance sheets. Funds received upon exercise of warrants will be recorded as common stock in the consolidated balance sheets as the exercise price represents the par value of the underlying common stock. August 2025 Offering In August 2025, the Company issued and sold 43,700,000 shares of its common stock, including 5,700,000 shares pursuant to the exercise of the underwriters’ option to purchase additional shares, at a price to the public of $ 3.30 per share. As a result of the offering, the Company received approximately $ 138.4 million in net proceeds, after deducting underwriting discounts, commissions and offering costs of $ 5.8 million. At-The-Market Equity Program In November 2023, the Company entered into Open Market Sale Agreement SM , or the Sales Agreement, with Jefferies LLC, acting as the Company’s agent and/or principal, or the Sales Agent, with respect to an “at the market offering” program under which the Company may, from time to time, at its sole discretion, issue and sell shares of its common stock having an aggregate offering price of up to $ 300.0 million through the Sales Agent. Pursuant to the Sales Agreement, any shares will be sold pursuant to the automatic shelf registration statement on Form S-3ASR (File No. 333-291348) filed with the SEC on November 7, 2025, which became automatically effective upon filing, including the base prospectus contained therein. Concurrently with the filing of this Annual Report on Form 10K, the Company plans to convert the Form S-3ASR to Form S-3 by post-effective amendments. The common stock will be sold at prevailing market prices at the time of the sale, and as a result, prices may vary. As of December 31, 2025, there have been no sales of common stock pursuant to the Sales Agreement. 8. Stock-Based Compensation 2019 Equity Incentive Plan The Company’s 2019 Stock Option and Grant Plan, or the 2019 Plan, provides for the Company to grant incentive stock options, non-qualified stock options, unrestricted stock awards, restricted stock awards and other stock-based awards to the officers, employees, consultants and other key persons of the Company. The 2019 Plan is administered by the board of directors, or at the discretion of the board of directors, by a committee of the board of directors. The exercise prices, vesting and other restrictions are determined at the discretion of the board of directors, or its committee if so delegated. In October 2022, the Company completed its IPO, and in connection with the closing, the board of directors determined that no further awards would be granted under the 2019 Plan. 2022 Stock Option and Incentive Plan In February 2022, the Company’s board of directors adopted, and in October 2022 its stockholders approved, the 2022 Plan, which became effective immediately preceding the date on which the registration statement for the Company’s IPO was declared effective by the SEC. The 2022 Plan allows the Company to make equity-based and cash-based incentive awards to its officers, employees, directors, and consultants. The 2022 Plan provides for the grant of incentive stock options, non-qualified stock options, stock appreciation rights, restricted common stock awards, restricted stock units and other stock-based awards. Stock options awarded under the 2022 Plan expire 10 years after the grant date and typically vest over four years . The shares of common stock underlying any awards under the 2022 Plan and the 2019 Plan that are forfeited, cancelled, held back upon exercise or settlement of an award to satisfy the exercise price or tax withholding, reacquired by the Company prior to vesting, satisfied without the issuance of stock, expire, or are otherwise terminated (other than by exercise) will be added back to the shares of common stock available for issuance under the 2022 Plan. The number of shares reserved and available for issuance under the 2022 Plan will increase on January 1 of each year, by five percent of the outstanding number of shares of common stock on the immediately preceding December 31 or such lesser number of shares as determined by the compensation committee. On January F-22 1, 2026, the annual increase for the 2022 Plan resulted in an additional 9,025,700 shares authorized for issuance being added to the 2022 Plan. As of December 31, 2025, the Company had 25,558,130 shares reserved under the 2022 Plan and the 2019 Plan, and 7,891,263 shares available for issuance under the 2022 Plan. 2022 Employee Stock Purchase Plan In February 2022, the Company’s board of directors adopted, and in October 2022 its stockholders approved, the 2022 Employee Stock Purchase Plan, or the 2022 ESPP. The 2022 ESPP provides for an annual increase on January 1 each year through January 1, 2032, by the least of (i) 971,350 shares of common stock, (ii) one percent of the outstanding number of shares of common stock on the immediately preceding December 31, or (iii) such number of shares of common stock as determined by the administrator of the 2022 ESPP. There was no annual increase for the 2022 ESPP on January 1, 2026. As of December 31, 2025, the Company had 1,522,025 shares available for issuance under the 2022 ESPP. Under the 2022 ESPP, the Company issued 231,166 shares of the Company’s common stock during the year ended December 31, 2025. 189,509 shares of the Company’s common stock were issued during the year ended December 31, 2024 under the 2022 ESPP. Stock Option Valuation The following table presents, on a weighted-average basis, the assumptions used in the Black-Scholes option-pricing model to determine the fair value of stock options granted: Year ended December 31, 2025 2024 Risk-free interest rate 3.9 % 4.2 % Expected term (in years) 6.2 5.8 Expected volatility 75.8 % 78.4 % Expected dividend yield — % — % Time-Based Stock Options The following table summarizes the Company’s time-based stock option activity for the year ended December 31, 2025: Number of Options Weighted-Average Exercise Price 1 Weighted-Average Remaining Contractual Term (in years) Aggregate Intrinsic Value (in thousands) Outstanding at December 31, 2024 11,410,691 $ 5.92 8.10 $ — Granted 7,952,594 2.21 Exercised ( 222,022 ) 3.52 Forfeited ( 3,503,960 ) 7.20 Outstanding at December 31, 2025 15,637,303 $ 3.76 7.29 $ 9,880 Vested and exercisable at December 31, 2025 7,184,947 $ 4.72 6.12 $ 976 Vested and expected to vest at December 31, 2025 15,637,303 $ 3.76 7.29 $ 9,880 1 Weighted-average exercise price for shares outstanding at the beginning of the period and at the end of period reflect the exercise price resulting from the one-time repricing, which is discussed in detail below. F-23 Other information related to the time-based stock option activity of the Company was as follows: Year ended December 31, 2025 2024 Weighted-average fair value of options granted $ 1.57 $ 5.60 Intrinsic value of options exercised (in thousands) $ 419 $ 70 As of December 31, 2025 there was $ 27.5 million of total unrecognized compensation cost related to time-based unvested stock options, and the Company expects to recognize such amount over a remaining weighted-average period of 2.5 years. Performance-Based Stock Options The Company has granted stock options to certain employees to purchase shares of common stock that contain performance-based vesting criteria related to corporate milestones. The fair value of each option grant was estimated on the date of grant. Recognition of stock-based compensation expense associated with these performance-based stock options commences when the performance condition is considered probable of achievement, using management’s best estimates, which consider the inherent risk and uncertainty regarding the future outcomes of the milestones. The following table summarizes the Company’s performance-based stock option activity for the year ended December 31, 2025: Number of Options Weighted-Average Exercise Price 1 Weighted-Average Remaining Contractual Term (in years) Aggregate Intrinsic Value (in thousands) Outstanding at December 31, 2024 1,061,730 $ 5.90 8.35 $ — Granted 1,000,000 2.30 Exercised — — Forfeited ( 32,166 ) 7.96 Outstanding at December 31, 2025 2,029,564 $ 4.10 7.53 $ 1,495 Vested and exercisable at December 31, 2025 813,480 $ 5.26 5.88 $ — 1 Weighted-average exercise price for shares outstanding at the beginning of the period and at the end of period reflect the exercise price resulting from the one-time repricing, which is discussed in detail below. Other information related to the performance-based stock option activity of the Company was as follows: Year ended December 31, 2025 2024 Weighted-average fair value of options granted $ 1.76 $ 5.27 As of December 31, 2025 there was $ 3.1 million of total unrecognized compensation cost related to performance-based stock options. Market-Based Stock Options The Company has granted stock options to purchase shares of common stock that contain market-based vesting criteria. The fair value of each option grant was estimated on the date of grant using the Monte Carlo valuation method. Expense is recognized when the option vests upon the satisfaction of certain performance criteria tied to the Company’s stock price. F-24 Number of Options Weighted-Average Exercise Price Weighted-Average Remaining Contractual Term (in years) Aggregate Intrinsic Value (in thousands) Outstanding at December 31, 2024 — $ — 0.00 $ — Granted 300,000 1.34 Exercised — — Forfeited — — Outstanding at December 31, 2025 300,000 $ 1.34 9.38 $ 641 Vested and exercisable at December 31, 2025 — $ — 0.00 $ — Other information related to the market-based stock option activity of the Company was as follows: Year ended December 31, 2025 2024 Weighted-average fair value of options granted $ 1.12 $ — Repricing of Certain Outstanding Stock Options On June 22, 2025, the Company’s board of directors approved, and on August 1, 2025, or the Repricing Date, the Company’s stockholders approved, a one-time repricing, or the Option Repricing, of certain outstanding stock options granted to, and held by, certain of the Company’s current employees, including its executive officers, and members of the board of directors through the Repricing Date, or, collectively, the Eligible Optionholders, under the 2019 Plan and 2022 Plan, or collectively, the Plans. The Option Repricing impacted shares of common stock, or Eligible Options, that have exercise prices in excess of $ 4.04 , or the Repriced Exercise Price, which was the closing trading price per share of the Company’s common stock on The Nasdaq Global Market on the Repricing Date. Effective as of the Repricing Date, the per share exercise price of each Eligible Option held by an Eligible Optionholder on the Repricing Date was automatically reduced to the Repriced Exercise Price. Under the terms of the Option Repricing, a Repriced Option will revert to its original exercise price per share if: i. exercised prior to the 18-month anniversary of the Repricing Date for Repriced Options held by members of the board of directors or executive officers of the Company, as applicable, or the one-year anniversary of the Repricing Date for Repriced Options held by all other employees of the Company, each referred to as a Retention Date; ii. an Eligible Optionholder’s Service Relationship (as defined in the Plans) is terminated by the Company for Cause (as defined in the applicable award agreement) prior to the applicable Retention Date; or iii. an Eligible Optionholder resigns from the Company (including as a member of the board of directors) for any reason prior to the applicable Retention Date, other than described below. Notwithstanding the foregoing, each Repriced Option shall retain the Repriced Exercise Price, to the extent it has not otherwise reverted to its original exercise price per share in accordance with the foregoing, and the ability to exercise such Repriced Option may be accelerated to earlier than the applicable Retention Date in the event of: i. a Sale Event (as defined in the Plans) prior to the applicable Retention Date; ii. the termination of the Eligible Optionholder’s Service Relationship by the Company without Cause or for “good reason,” or resignation by the Eligible Optionholder for “good reason,” to the extent provided for in the Eligible Optionholder’s employment agreement, offer letter or severance plan (as applicable); or iii. the Eligible Optionholder’s death or disability (as determined in accordance with the Plans, as applicable). Except as modified by the Option Repricing, all other terms and conditions of the Repriced Options, including, without limitation, any provisions with respect to vesting and term of the Repriced Options, will remain in full force and effect. As a result of the option repricing, the Company expects to recognize the incremental expense of F-25 $ 5.1 million over a weighted average period of 2.3 years. As of December 31, 2025, there was $ 3.5 million of unrecognized incremental expense, which is expected to be recognized over a period of 1.6 years. Performance-Based Restricted Common Stock Awards The Company awarded performance-based restricted common stock to employees and non-employees under its 2019 Plan. The fair value of each share of performance-based restricted common stock is based on the market price of the Company's common stock on the date of grant. Performance‑based restricted common stock awards vest upon the achievement of performance‑based milestones related to corporate milestones. Stock-based compensation expense associated with the performance-based restricted common stock is recognized if the performance condition is considered probable of achievement using the Company’s best estimates of the time to vesting for the achievement of the performance‑based milestones. Each reporting period, the Company updates its assessment of the probability that the performance-based milestones will be achieved. The fair value of the restricted common stock was based on the fair market value of the Company’s common stock on the date of grant. The following table summarizes the Company’s performance-based restricted common stock award activity for the year ended December 31, 2025: Number of Shares Weighted-Average Grant-Date Fair Value Unvested restricted common stock at December 31, 2024 3,472,546 $ 0.06 Issued — — Vested — — Repurchased — — Unvested restricted common stock at December 31, 2025 3,472,546 $ 0.06 Restricted Stock Units During the year ended December 31, 2025, the Company issued 2,000,000 restricted stock units. Further, the Company determined that as the obligation underlying the restricted stock units were satisfied during the period, the $ 8.2 million expense related to the restricted stock units shall be recognized in full during the year ended December 31, 2025. The amount is recorded as research and development expense on the Company’s consolidated statements of operations. Stock-Based Compensation The following table below summarizes the classification of the Company’s stock-based compensation expense related to stock options and restricted common stock awards in the consolidated statements of operations and comprehensive loss: Year ended December 31, (in thousands) 2025 2024 Stock-based compensation expense: Research and development $ 19,372 $ 12,704 General and administrative 9,896 13,364 Total stock-based compensation expense $ 29,268 $ 26,068 F-26 9. License and Collaboration Agreements License Agreements with Broad Institute 2019 License Agreement with Broad Institute In September 2019, the Company entered into a license agreement with Broad Institute, Inc., or Broad Institute, for certain patents related to the field of prevention or treatment of human disease by editing or targeting DNA, or the Broad License Agreement. In subsequent periods, the Broad License Agreement has been subject to amendments. Under the Broad License Agreement, Broad Institute granted the Company (i) an exclusive, worldwide license under the licensed patent rights solely to offer for sale, sell, have sold and import products covered by such licensed patent rights, or licensed products, solely for use within the Prime Broad Field (subject to certain specified limitations and exclusions with respect to certain applications), (ii) a non-exclusive, worldwide license under the licensed patent rights solely to make, have made, offer for sale, sell, have sold, and import licensed products solely for use in the Prime Broad Field, (iii) a non-exclusive, worldwide license under the licensed patent rights solely to make, have made, offer for sale, sell, have sold and import other products that are enabled by (a) the licensed patent rights or (b) the use of certain materials transferred to the Company by Broad Institute, solely for the prevention or treatment of human diseases and (iv) a non-exclusive, worldwide license solely for internal research. Further, with respect to DNA delivery or targeting applications covered by the licensed patent rights, the exclusive license granted to the Company by Broad Institute is limited only to “prime editor” products and specifically excludes applications relating to the production or processing of small or large molecules, including for the prevention or treatment of human disease. Under the Broad License Agreement, the Company also has the right to grant sublicenses to its affiliates and third parties, subject to certain requirements. As partial consideration for the license, the Company made a upfront payment of $ 0.5 million to Broad Institute. Under the Broad License Agreement, the Company is obligated to pay Broad Institute an annual license maintenance fee of low six-figures dollar amount beginning in 2022. Broad Institute is also entitled to receive clinical and regulatory milestone payments up to a total of $ 20.0 million and sales-based milestone payments up to a total of $ 54.0 million per licensed product. Further, the Broad Institute is entitled to receive mid-single digit percentage royalties, subject to customary offsets and reductions, on net sales of licensed products, and low single-digit percentage royalties of enabled products. Unless earlier terminated, the Broad License Agreement will remain in effect until the later of (i) the last to expire valid claim of an issued patent or pending patent application within the licensed patent rights covering the Company’s licensed products or (ii) the expiration of the last royalty term for a licensed product in a country. The Company can terminate the Broad License Agreement for convenience after a certain period of time following prior written notice to Broad Institute. Each party may terminate the Broad License Agreement for the other party’s uncured material breach within a specified time period following notice of such breach. Broad Institute may also immediately terminate the Broad License Agreement (i) to the extent the Company (or its affiliates or sublicensees) challenges a licensed patent right, (ii) upon the Company’s bankruptcy or insolvency or (iii) if the Company fails to procure and maintain insurance. 2022 License Agreement with Broad Institute In December 2022, the Company entered into a second license agreement with Broad Institute, or the 2022 Broad License Agreement. Under the 2022 Broad License Agreement, Broad Institute grants to us certain rights and licenses under the patent rights it owns or controls related to MMR inhibition and prime editing improvements and specifically, (i) an exclusive, worldwide license under the licensed patent rights solely to offer for sale, sell, have sold and import products covered by such licensed patent rights, or licensed products, solely for use within the Prime Broad Field (subject to certain specified limitations and exclusions with respect to certain applications), (ii) a non-exclusive, worldwide license under the licensed patent rights solely to make, have made, offer for sale, sell, have sold, and import licensed products solely for use in the Prime Broad Field, (iii) a non-exclusive, worldwide license under the licensed patent rights solely to make, have made, offer for sale, sell, have sold and import other products that are enabled by (a) the licensed patent rights or (b) the use of certain materials transferred to us by Broad Institute, solely for the prevention or treatment of human diseases and (iv) a non-exclusive, worldwide license solely for internal research. Further, with respect to DNA delivery or targeting applications covered by the licensed patent F-27 rights, the exclusive license granted to us by Broad Institute is limited only to “prime editor” products and specifically excludes applications relating to the production or processing of small or large molecules, including for the prevention or treatment of human disease. Under the Broad License Agreement, the Company also has the right to grant sublicenses to its affiliates and third parties, subject to certain requirements. The Company is also obligated to pay Broad Institute an annual license maintenance fee of mid five-figures for the term of the Agreement. Broad Institute is also entitled to receive clinical and regulatory milestone payments for a limited category of royalty-bearing products, up to a total of $ 2.0 million and sales-based milestone payments up to a total of $ 3.0 million. Further, Broad Institute is entitled to receive royalties of less than 0.2 % on net sales of royalty bearing products. Unless earlier terminated, the 2022 Broad License Agreement will remain in effect until the later of (i) the last to expire valid claim of an issued patent or pending patent application within the licensed patent rights covering our licensed products or (ii) the expiration of the last royalty term for a royalty bearing product in a country. The Company can terminate the 2022 Broad License Agreement for convenience following prior written notice to Broad Institute. Each party may terminate the 2022 Broad License Agreement for the other party’s uncured material breach. Broad Institute may also immediately terminate the 2022 Broad License Agreement (i) to the extent we (or our affiliates or sublicensees) challenge a licensed patent right, (ii) upon our bankruptcy or insolvency or (iii) if we fail to procure and maintain insurance. Side Letter No. 1 to The Broad Institute License Agreement In connection with the BMS Collaboration Agreement, discussed below, the Company entered into a Letter Agreement, or the First Letter Agreement, with Broad Institute in September 2024, which amends the Broad License Agreement to modify certain obligations of Company and rights of Broad Institute in relation to the BMS Collaboration Agreement as a sublicense under the Broad License Agreement. The First Letter Agreement, among other things, modifies the royalty and certain commercial milestones that the Company is obligated to pay to Broad Institute on net sales of products under the BMS Collaboration Agreement. Except as expressly stated in the 2024 Broad Amendment, all other terms and provisions of the Broad License Agreement remain in full force and effect. Amounts due to Broad Institute as a result of the BMS Collaboration Agreement are recorded as accrued expenses on the consolidated balance sheet as of December 31, 2025. Amendment No. 4 and Amendment No. 5 to The Broad Institute License Agreement In September 2025, the Company entered into a Fourth Amendment to License Agreement, or the Fourth Amendment, and Fifth Amendment to License Agreement, or the Fifth Amendment, and, together with the Fourth Amendment, the Amendments, with Broad Institute, which amended the Broad License Agreement, to, among other things, modify certain licensed patent applications listed therein. Except as expressly stated in the Amendments, all other terms and provisions of the Broad License Agreement shall remain in full force and effect. Side Letter No. 2 to The Broad Institute License Agreement In connection with the Amendments, the Company also entered into a second letter agreement, or the Second Letter Agreement, with Broad Institute in September 2025, which amends the Broad License Agreement. The Second Letter Agreement, among other things, modifies certain development milestones and related payment obligations under the BMS Collaboration Agreement. Except as expressly stated in the Second Letter Agreement, all other terms and provisions of the Broad License Agreement shall remain in full force and effect. Broad Pledge In February 2021, the Company committed to donate $ 5.0 million to Broad Institute and Harvard University annually for 14 years, commencing in 2022, or the Pledge. The Pledge is intended to be used for research and development related to new genome editing technologies, for example Prime Editing, improve on existing genome-editing technologies, identify delivery mechanisms for these technologies and apply these technologies to the understanding and treatment of rare genetic diseases. The Company can terminate the Pledge at its discretion, subject to providing one year of funding from the date of termination. In August 2022, the Company amended and F-28 restated the Pledge to clarify that the funds may be used by the laboratory of David Liu, who is a member of Broad Institute and a faculty member at Harvard. The Company accounts for this Pledge as research and development expenses as it has access to certain data generated as a result of the Pledge. For both the years ended December 31, 2025 and 2024, the Company recognized $ 5.0 million of research and development expense in connection with the Pledge. Beam Collaboration Agreement — Related Party In September 2019, the Company entered into a collaboration agreement with Beam, or the Beam Collaboration Agreement, to collaborate on the research, development, manufacture and commercialization of certain Prime Editing products within a specified field and provide each other with access and licenses to certain proprietary technology to advance the other’s progress. Under the Beam Collaboration Agreement, the Company granted Beam an exclusive (even as to the Company and its affiliates), worldwide license under (i) certain Prime Editing technology, know-how and patent rights that the Company controls during the initial term, and improvements thereto that the Company controls for a specified number of years following the initial term, and (ii) the Company’s interest in certain jointly-owned collaboration technology, in each case, solely to develop, make, have made, use, offer for sale, sell, import and commercialize licensed products only in the Beam field. Beam granted to the Company certain non-exclusive, worldwide licenses under certain technology, know-how and patent rights, including under certain CRISPR or delivery-related technology, know-how and patent rights, that it controls during the initial term, and improvements thereto that Beam controls for a specified number of years following the initial term, solely to develop, make, have made, use, offer for sale, sell, import and commercialize products only in the Company’s field. Subject to certain provisions, on a licensed product-by-licensed product basis, we have the right to elect to share equally with Beam in the profits and losses in the United States for Beam’s licensed products. We may exercise such right for each licensed product within a specified period of time. Any such licensed product for which we exercise such right we refer to as a collaboration product. Before and within 30 days after the filing of an IND for a development candidate being developed under the Beam Collaboration Agreement, Beam has the option to designate up to a mid-single digit number of licensed products for which the Company is not permitted to exercise the profit share right, or the Beam Option. Under the Beam Collaboration Agreement, a licensed product for which the Company has not exercised its profit share option or for which Beam has exercised the Beam Option is collectively referred to as “protected product.” Unless the Company exercises its profit sharing option for a licensed product, Beam is solely responsible for the development and commercialization of licensed products in the Beam field under the Beam Collaboration Agreement. If Beam exercises its option for a protected product, Beam will owe Prime a payment of $ 5.0 million if the product is developed for non-sickle cell disease or $ 10.0 million if the product is developed for sickle cell disease. Under the terms of the Beam Collaboration Agreement, the Company is entitled to following milestones: Development milestones Protected product Up to $ 35.5 million Collaboration product Up to $ 17.8 million Sales milestones Protected product Up to $ 84.5 million Collaboration product Up to $ 42.3 million For eligible products, Beam is obligated to pay the Company tiered royalties, subject to customary offsets and reductions, ranging from a high-single digit percentage to a low double-digit percentage, but less than teens on net sales of protected products worldwide and net sales of collaboration products outside of the United States. In addition, Beam must reimburse the Company for certain payments the Company is required to make to its third-party licensors attributable to Beam’s exercise of any sublicense the Company grants to Beam, including payments it makes to Broad Institute under the Broad License Agreement. F-29 If the Company develops a product that is covered by the technology, know-how or patent rights that Beam licenses to the Company under the Beam Collaboration Agreement, which it refers to as a Prime product, the Company is obligated to pay to Beam a low single digit royalty on its worldwide net sales of such any product on a Prime product-by-Prime product and country-by-country basis, subject to certain customary reductions, to a floor. Unless earlier terminated in accordance with its terms, the Beam Collaboration Agreement will expire on the later of (a) expiration of the last royalty term for a product on which a party is obligated to pay royalties to the other party or (b) with respect to any collaboration product, the date on which neither party is developing or commercializing any such collaboration product in the United States. After expiration of the initial term, Beam can terminate the Beam Collaboration Agreement for convenience in its entirety, or on a licensed product-by-licensed product or subfield-by-subfield basis, with prior written notice to the Company. Each party may terminate the Beam Collaboration Agreement for (a) the other party’s uncured material breach, (b) upon the insolvency or bankruptcy of the other party or (c) immediately to the extent the other party (or its affiliates or sublicensees) challenges a patent right licensed to such party. On the first anniversary of the Beam Collaboration Agreement, the Company received 200,307 shares of Beam common stock, with a fair value of $ 5.5 million and, in return, the Company issued to Beam 1,608,337 shares of the Company’s common stock, with a fair value of $ 0.2 million. The Company is currently engaged in arbitration proceedings with Beam regarding the Beam Collaboration Agreement. A dispute arose between the parties following the Company’s March 18, 2025 announcement that it is developing a Prime Editing-based treatment for alpha-1 antitrypsin deficiency, or AATD. On April 16, 2025, Beam filed an arbitration demand with the American Arbitration Association, or AAA, alleging that the Company has breached the Agreement by developing a product for the treatment of AATD and by allegedly not complying with certain obligations to transfer technical information to Beam pursuant to the Beam Collaboration Agreement. Beam also makes related claims for trade secret misappropriation and various business torts based on similar allegations, including allegations made on information and belief. Beam seeks both declaratory, injunctive, and monetary relief, but has not yet quantified the amount of damages it seeks. On April 18, 2025, the Company filed an arbitration demand with the AAA seeking a declaration that the Company’s AATD program is within our “Field” as defined by the Beam Collaboration Agreement. The arbitrations have been consolidated, and the consolidated proceeding remains ongoing. If the final resolution of the matter is adverse to the Company, the arbitration panel may provide Beam with relief including, among other things, monetary damages and/or an order that the Company cease work on its AATD program and transfer such program to Beam. Accounting Considerations The Company concluded that the Beam Collaboration Agreement and the Beam Mutual Subscription Agreement should be combined and treated as a single arrangement for accounting purposes as the agreements were entered into contemporaneously and in contemplation of one another. The Company determined that the combined agreements are accounted for under ASC 606 . The Company identified the following performance obligations: (i) exclusive, worldwide license to certain Prime patents, (ii) non-exclusive, worldwide licenses to CRISPR technology and (iii) joint research committee participation. The Company also evaluated whether the Beam Option and the Company’s right to elect collaboration products in the Beam Collaboration Agreement represented material rights that would give rise to a performance obligation and concluded that neither the Beam Option nor the Company’s right to elect collaboration products convey a material right to Beam and therefore are not considered separate performance obligations within the Beam Collaboration Agreement. There have been no protected product or collaboration products to date. Under the Beam Collaboration Agreement, the Company is eligible to receive certain milestones and royalties regardless of whether any options are exercised, which are considered variable consideration. At each reporting period, the Company evaluates whether milestones are considered probable of being reached and, to the extent that a significant reversal would not occur in future periods, estimates the amount to be included in the transaction price. During the years ended December 31, 2025 and 2024 the Company did not receive any milestone payments and all variable consideration related to the Beam Collaboration Agreement remained fully constrained. The Company assessed the above promises and determined that the exclusive license for certain Prime products and non-exclusive licenses to CRISPR technology represent performance obligations within the scope of ASC 606. The exclusive license for certain Prime products F-30 and non-exclusive licenses to CRISPR technology are considered functional intellectual property and distinct from other promises under the contract. The exclusive license for certain Prime products and non-exclusive licenses to CRISPR technology are considered functional licenses that are distinct in the context of the Beam Collaboration Agreement as Beam can benefit from the licenses on its own or together with other readily available resources. As the exclusive license for certain Prime products and non-exclusive licenses to CRISPR technology are delivered at the same time, they are considered one performance obligation at contract inception. The joint research committee performance promise is immaterial in the context of the contract. The Company determined the transaction price under ASC 606 at the inception of the Beam Collaboration Agreement to be $ 5.2 million, consisting of the value of the Beam equity investment under the Beam Mutual Subscription Agreement, when measured at fair value, less the value of the Prime shares issued to Beam of $ 0.2 million. The shares Prime issued to Beam represents a payment to a customer and is therefore a reduction of the transaction price. The Company recognizes revenue for the license performance obligations at a point in time, as control of these licenses are transferred upon issuance and Beam could begin to use and benefit from the licenses. There was no revenue recognized under the Beam Collaboration Agreement during the years ended December 31, 2025 or 2024. The change fair value of the related party short-term investment consisting of Beam shares are recognized as unrealized gain (loss) i n the consolidated statements of operations and comprehensive loss. Bristol-Myers Squibb — Related Party In September 2024, the Company entered into the BMS Collaboration Agreement with Juno Therapeutics, Inc., a wholly-owned subsidiary of Bristol-Myers Squibb, or BMS. Under the terms of the BMS Collaboration Agreement, the Company granted to BMS an exclusive worldwide license to certain Prime Editing technology for developing, manufacturing and commercializing ex vivo T-cell therapeutic products directed to select targets. Additionally, on the Effective Date, the Company entered into the BMS Purchase Agreement with BMS, pursuant which the Company agreed to sell and issue shares of its common stock to BMS. Research Collaboration and License Agreement Pursuant to the BMS Collaboration Agreement, the Company will design Prime Editing reagents to be used by BMS to develop, manufacture and commercialize ex vivo T-cell therapeutic products directed to specific targets selected by BMS. Under the BMS Collaboration Agreement, the Company received a $ 55.0 million upfront payment and received a $ 55.0 million equity investment from BMS (as described below). The Company is also eligible to receive more than $ 3.5 billion in milestones, including up to $ 185 million in preclinical milestones, up to $ 1.2 billion in development milestones, and up to $ 2.1 billion in commercialization milestones, along with royalties on net sales. Unless earlier terminated, the term of the BMS Collaboration Agreement continues until expiration of the last royalty term for the applicable product in the applicable country. The BMS Collaboration Agreement is subject to customary termination provisions, including termination by a party for the other party’s uncured, material breach. Stock Purchase Agreement On the Effective Date, the Company entered into the BMS Purchase Agreement with BMS, pursuant to which the Company agreed to issue and sell, and BMS agreed to purchase, in the Offering, 11,006,163 Shares of the Company’s Common Stock for an aggregate purchase price of $ 55.0 million pursuant to the terms and conditions thereof. Pursuant to the terms of the BMS Purchase Agreement, BMS has agreed not to, directly or indirectly, sell or transfer any of the Shares until September 30, 2027 subject to specified conditions and exceptions. The BMS Collaboration Agreement and Stock Purchase Agreement were accounted for as a combined contract. The Common Stock were recorded at their fair value as permanent equity. F-31 Accounting Considerations The Company assessed the BMS Collaboration Agreement and concluded that BMS is a customer. The Company identified the following promises under the contract: (i) a license to develop, manufacture and commercialize the ex vivo T-cell therapeutic products to select targets, (ii) obligation to perform research services, (iii) participation in various committees, (iv) technology transfer services, and (v) regulatory support services. The Company assessed the promised goods and services to determine if they are distinct. Based on this assessment, the Company determined that BMS cannot benefit from the promised goods and services separately from the others as they are highly interrelated and interdependent and therefore not distinct. Accordingly, the promised goods and services represent one combined performance obligation and the entire transaction price will be allocated to that single combined performance obligation. At contract inception, the transaction price was determined to be $ 72.0 million, which represents the aggregate of the upfront nonrefundable payment for the BMS Collaboration Agreement and the premium paid by BMS on its equity investment in the Company. Development milestones were fully constrained. The Company recognizes the portion of the transaction price as the single performance obligation is satisfied, using an input method, in proportion to costs incurred to date as compared to total costs incurred and expected to be incurred in the future to satisfy the underlying obligation. The transfer of control occurs over this period and, in management’s judgment, is the best measure of progress towards satisfying the performance obligation. Cost to perform the Company’s obligations under the BMS Collaboration Agreement will be recognized as research and development expenses in the period incurred. Revenue recognized from the BMS Collaboration Agreement was as follows: Year Ended December 31, (in thousands) 2025 2024 Collaboration revenue — related party $ 4,586 $ 1,609 Supplemental information related to the BMS Collaboration Agreement consisted of the following: December 31, (in thousands) 2025 2024 Deferred revenue — related party $ 7,824 $ 7,092 Deferred revenue, net of current — related party 58,127 63,218 Cystic Fibrosis Foundation In July 2025, the Company entered into an agreement with the Cystic Fibrosis Foundation, or CFF, under which CFF has agreed to provide up to $ 24 million in additional funding to accelerate the development of Prime Editors designed to permanently correct cystic fibrosis-related lung disease. The $ 24 million funding includes two equal tranches, subject to certain closing conditions and scientific milestones. The first tranche included a $ 6 million cash funding, or Royalty Funding, received in August 2025, and a $ 6 million equity investment in the Company, which was received as part of the August 2025 offering. Any proceeds under the second tranche are payable subject to achieving specific milestones which have not been achieved to date. The Company is obligated to return any of the Royalty Funding not used in development of the program covered by this agreement. In return, the Company has agreed to pay to CFF royalties on future sales of any products covered under this agreement, to be determined based on the aggregate annual net sales of products and net amount of Royalty Funding received by the Company. In addition, in the event of a sale, license or transfer to a third-party of rights in the technology developed under this agreement, or a change of control transaction, the Company will pay a percentage of the proceeds received to CFF, up to 2.5 x the net Royalty Funding received. CFF’s additional investment builds on initial funding received under the Company’s therapeutic development agreement with CFF in January 2024. F-32 Accounting Considerations Due to the Company’s obligation to repay the Royalty Funding in the event of a change in control regardless of the outcome of the research and development associated with the payment, the Company determined that CFF’s $ 6 million Royalty Funding represented a liability. This amount, along with the $ 12.0 million received under the CFF agreement entered into in 2024, half of which was received in 2024 and half of which was received in 2025, is recorded as research funding liability on the condensed consolidated balance sheets. 10. Net Loss per Share As described in Note 2, Summary of Significant Accounting Policies , for periods in which the Company reports a net loss, potentially dilutive securities have been excluded from the computation of diluted net loss per share as their effects would be anti-dilutive. Therefore, the weighted average number of common shares outstanding used to calculate both basic and diluted net loss per share is the same. The Company excluded the following potential common shares presented based on amounts outstanding at period end, from the computation of diluted net loss per share for the periods indicated because including them would have had an anti-dilutive effect: Year Ended December 31, 2025 2024 Anti-dilutive common stock equivalents: Stock options to purchase common stock 16,450,783 11,900,921 Unvested restricted common stock awards 3,472,546 3,497,474 Total anti-dilutive common stock equivalents 19,923,329 15,398,395 Basic and diluted loss per share is computed by dividing net loss by the weighted-average common shares outstanding: Year Ended December 31, (in thousands, except share and per share data) 2025 2024 Numerator: Net loss attributable to common stockholders $ ( 201,142 ) $ ( 195,882 ) Denominator: Weighted-average common shares outstanding, basic and diluted 148,758,527 118,600,381 Net loss per share attributable to common stockholders, basic and diluted $ ( 1.35 ) $ ( 1.65 ) The weighted-average number of common shares outstanding used in the basic and diluted net loss per share calculations for the year ended December 31, 2024 includes the weighted-average effect of pre-funded warrants sold by the Company to purchase 3,200,005 shares of the Company's common stock. The shares of common stock underlying the pre-funded warrants are considered outstanding for the purposes of computing earnings per share, because the shares may be issued for little or no consideration, they are fully vested, and the pre-funded warrants are immediately exercisable upon their issuance date. Refer to Note 7, Stockholder’s Equity , for details on the holder’s May 2025 exercise of the pre-funded warrants. F-33 11. Income Taxes The Company did not have any income tax expense (benefit) during the years ended ended December 31, 2025 or 2024. A reconciliation of the U.S. federal statutory income tax rate to the Company’s effective income tax rate for the year ended December 31, 2025 is as follows: Rate (%) Amount (in thousands) U.S. federal statutory tax rate 21.0 % Year Ended $ ( 42,240 ) State and local taxes, net of federal effect — % Year Ended — Tax credits Year Ended Research and development credit 2.3 % Year Ended ( 4,634 ) Changes in valuation allowances ( 22.3 ) % Year Ended 44,865 Nontaxable or nondeductible items Year Ended Stock compensation ( 0.3 ) % Year Ended 633 162(m) Comp Limit — % Year Ended 62 Other items ( 0.1 ) % Year Ended 291 Other Adjustments ( 0.6 ) % Year Ended 1,023 Effective income tax rate — % Year Ended $ — A reconciliation of the U.S. federal statutory income tax rate to the Company’s effective income tax rate for the year ended December 31, 2024 is as follows: Rate (%) Federal income tax expense at statutory rate 21.0 % State income taxes, net of federal benefit 7.4 % Tax credits 2.6 % Permanent differences ( 0.9 ) % Other 0.8 % Change in valuation allowance ( 30.8 ) % Effective income tax rate — % F-34 Net deferred tax assets (liabilities) consisted of the following: December 31, (in thousands) 2025 2024 Deferred tax assets: Capitalized research and development costs $ 50,092 $ 74,605 U.S. and state net operating loss carryforwards 116,777 61,501 Depreciation and amortization 14,060 12,829 Tax credits 30,004 22,986 Accrual 19,830 2,334 Lease Liability 31,826 12,228 Stock Compensation 11,315 6,005 Other — 141 Total deferred tax assets 273,904 192,629 Deferred tax liabilities: Right of Use Asset ( 34,491 ) ( 12,852 ) Total deferred tax liabilities ( 34,491 ) ( 12,852 ) Valuation allowance ( 239,413 ) ( 179,777 ) Net deferred tax assets (liabilities) $ — $ — The following is a summary of the Company’s net operating loss and tax credit carryforwards, both of which may be available to reduce future tax liabilities: December 31, (in thousands) 2025 2024 U.S. federal net operating loss - do not expire $ 429,230 $ 226,904 State net operating loss - expire at various dates beginning in 2039 421,882 219,351 Federal research and development tax credits - expire at various dates beginning in 2040 19,717 15,082 State research and development tax credits - expire at various dates beginning in 2036 13,021 10,005 Utilization of the U.S. federal and state net operating loss carryforwards and research and development tax credit carryforwards may be subject to a substantial annual limitation under Sections 382 and 383 of the Internal Revenue Code of 1986, and corresponding provisions of state law, due to certain 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 and tax liabilities. In general, an ownership change, as defined by Section 382, results from transactions increasing the ownership of certain stockholders or public groups in the stock of a corporation by more than 50 percentage points 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 net operating loss carryforwards or research and development tax credit carryforwards would be subject to an annual limitation, 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. Any limitation may result in expiration of a portion of the net operating loss carryforwards or research and development tax credit carryforwards before their utilization. Further, until a study is completed by the Company and any limitation is known, no amounts are being presented as an uncertain tax position. On July 4, 2025, President Trump signed H.R. 1, the “One Big Beautiful Bill Act”, or the Act, into law. The legislation includes several changes to federal tax law that are designed to allow for more favorable deductibility of certain business expenses and more favorable rules for determining the limitation on business interest expense. The F-35 Company will continue to capitalize foreign R&D costs this year and amortize over 15 years. For US R&D costs, the Company expensed 2025 expenses and continues to amortize previously capitalized R&D costs over the original 5-year life. For the years ended December 31, 2025 and 2024, the Company capitalized foreign R&D costs of $ 11.7 million and $ 8.3 million, respectively. The Company has evaluated the positive and negative evidence bearing upon its ability to realize the deferred tax assets. Management has considered the Company’s history of cumulative net losses incurred since inception, expectation of future losses and lack of other positive evidence. For the years ended December 31, 2025 and 2024, the Company was in a net deferred tax asset position and therefore recorded a valuation allowance against the portion of its deferred tax assets that cannot be fully supported by the future reversal of existing deferred tax liabilities. The Company reevaluates the positive and negative evidence at each reporting period. For the year ended December 31, 2025, the valuation allowance increased primarily due to the increases in net operating loss carryforwards, capitalized research and development costs, and research and development tax credit carryforwards. The changes in the valuation allowance were as follows: Year Ended December 31, (in thousands) 2025 2024 Valuation allowance at beginning of year $ 179,777 $ 119,250 Increases (decreases) recorded to income tax provision 59,636 60,527 Valuation allowance at end of year $ 239,413 $ 179,777 The Company assesses the uncertainty in its income tax positions to determine whether a tax position of the Company is more likely than not to be sustained upon examination, including resolution of any related appeals of litigation processes, based on the technical merits of the position. For tax positions meeting the more-likely-than-not threshold, the tax amount recognized in the financial statements is reduced by the largest benefit that has a greater than 50 percent likelihood of being realized upon the ultimate settlement with the relevant taxing authority. As of December 31, 2025, the Company had not recorded any reserves for uncertain tax positions or related interest and penalties. The Company files income 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. Since the Company is in a loss carryforward position, the Company is generally subject to examination by the U.S. federal, state and local income tax authorities for all years in which a loss carryforward is available. As of December 31, 2025, there were no pending tax examinations. The Company is open to future tax examination under statute from 2019 to the present. 12. Commitments and Contingencies Leases The Company’s commitments under its operating leases are described in Note 6, Leases . License and Collaboration Agreements The Company entered into various license and collaboration agreements under which it is obligated to make fixed and contingent payments as described in Note 9, License and Collaboration Agreements . Legal Proceedings From time to time, the Company may become involved in legal proceedings or other litigation relating to claims arising in the ordinary course of business. The Company accrues a liability for such matters when it is probable that future expenditures will be made and that such expenditures can be reasonably estimated. Significant judgment is required to determine both probability and estimated exposure amount. Legal fees and other costs associated with such proceedings are expensed as incurred. Except as described in Note 9, License and Collaboration Agreements , F-36 we do not have any ongoing legal proceedings that, based on our estimates, could have a material effect on our consolidated financial statements. 13. Related Party Transactions Agreements with Jeffrey Marrazzo In February 2024, the Company entered into an advisory services agreement, or Marrazzo Agreement, with Jeffrey Marrazzo, a member of the board of directors. Under the Marrazzo Agreement, Mr. Marrazzo agreed to provide certain professional services to the Company separate from and in addition to his service as a member of our board of directors. For his services, the Company agreed to pay Mr. Marrazzo an annual fee of $ 50,000 per year in addition to the grant of an option to purchase 250,000 shares of the Company’s common stock, which has a grant date fair value of $ 1.5 million. The Marrazzo Agreement expired in February 2025. Additionally, Mr. Marrazzo and the Company entered into an executive chair agreement, or the Executive Chair Agreement, in May 2025. Under the Executive Chair Agreement, Mr. Marrazzo agreed to provide services as the executive chair of our board of directors, and the Company agreed to pay Mr. Marrazzo an annual fee of $ 100,000 per year in addition to the grant of options to purchase a total of 1,000,000 shares of the Company’s common stock consisting of (i) a time-based option to purchase 500,000 shares, (ii) a performance-based option to purchase 200,000 shares, and (iii) a market-based option to purchase 300,000 shares. The grant of options has a aggregate grant date fair value of $ 1.0 million. The Executive Chair Agreement will continue indefinitely until terminated in accordance with its terms. If the Executive Chair Agreement is terminated between six-months and one-year of its effective date, a minimum of 250,000 shares subject to the time-based option will vest. In the event of a Sale Event (as defined in the 2022 Plan), all of the then-outstanding and unvested portions of the time-based option, 50 % of the then-outstanding and unvested portions of the performance-based option, and any of the then-outstanding and unvested portions of the market-based option for which the applicable stock-price milestone has been satisfied in connection with the Sale Event, will become vested and exercisable. Bristol-Myers Squibb In September 2024, the Company and BMS, a related party, entered into the BMS Collaboration Agreement and the BMS Purchase Agreement. BMS is a related party due to its share of ownership of the Company. For amounts recognized under the BMS Collaboration Agreement, refer to Note 9, Licenses and Collaboration Agreements . F-37