DEF 14A of Solid Biosciences Inc., Apr 23, 2026

DEF 14A of Solid Biosciences Inc.

Filed Apr 23, 2026 · FY20250001193125-26-173642

Open on EDGAR

  1. PROPOSAL NO. 1—ELECTION OF CLASS II DIRECTORS

    PROPOSAL NO. 1—ELECTION OF CLASS II DIRECTORS Our Board is divided into three classes, with one class of our directors standing for election each year. Directors in each class are elected at the annual meeting of stockholders held in the year in which the term for their class expires and hold office for a three-year term until the election and qualification of their successors and subject to their earlier death, resignation or removal. In accordance with our Certificate of Incorporation and bylaws, our directors may fill existing vacancies on the Board by appointment. The members of the classes are divided as follows: • the Class I Directors are Alexander Cumbo, Ilan Ganot and Sukumar Nagendran and their term will expire at the annual meeting of stockholders to be held in 2028; • the Class II Directors are Clare Kahn, Adam Stone and Lynne Sullivan and their term expires at the Annual Meeting; and • the Class III Directors are Martin Freed, Georgia Keresty and Ian Smith and their term expires at the annual meeting of stockholders to be held in 2027. Our Certificate of Incorporation and bylaws provide that the authorized number of directors may be changed only by resolution of our Board. Our Certificate of Incorporation and bylaws also provide that our directors may be removed only for cause by the affirmative vote of the holders of at least two-thirds of the votes that all our stockholders would be entitled to cast in an annual election of directors, and that any vacancy on our Board, including a vacancy resulting from an enlargement of our Board, may be filled only by vote of a majority of our directors then in office. Our Board, on the recommendation of our nominating and corporate governance committee, has nominated Clare Kahn, Adam Stone and Lynne Sullivan for election as Class II Directors at the Annual Meeting. Dr. Kahn, Mr. Stone and Ms. Sullivan are standing for re-election by the stockholders at this Annual Meeting. Each director that is elected at the Annual Meeting will be elected to serve for a three-year term that will expire at our annual meeting of stockholders to be held in 2029. If no contrary indication is made, proxies in the accompanying form will be voted “FOR” Clare Kahn, Adam Stone and Lynne Sullivan or, in the event that any of these candidates is not a candidate or is unable to serve as a director at the time of election (which is not currently expected), for any nominee who is designated by our Board to fill the vacancy. We have no formal policy regarding board diversity, but our corporate governance guidelines provide that the background and qualifications of the members of our Board considered as a group should provide a significant breadth of experience, knowledge, and ability to assist our Board in fulfilling its responsibilities. Our priority in selection of board members is identification of members who will further the interests of our stockholders through their established record of professional accomplishment, the ability to contribute positively to the collaborative culture among board members, knowledge of our business, understanding of the competitive landscape and adherence to high ethical standards. Certain individual skills and qualifications of our directors, which we believe contribute to the effectiveness of the Board as a whole, are described in this proxy statement.

  2. Information Regarding Directors

    Information Regarding Directors The information set forth below as to the directors and Director Nominees, which includes their name and age as of April 1, 2026, has been furnished to us by the directors and Director Nominees. OUR BOARD UNANIMOUSLY RECOMMENDS THAT THE STOCKHOLDERS VOTE “FOR” THE ELECTION OF EACH OF THE DIRECTOR NOMINEES.

  3. Nominees for Election to the Board

    Nominees for Election to the Board

  4. Term Expiring at the 2029 Annual Meeting of Stockholders, if elected at the Annual Meeting (Class II)

    Clare Kahn, Ph.D. has served as a member of our Board of Directors since March 2021 and has served as a consultant to us since June 2022. Dr. Kahn has served as R&D Strategy Officer at X-VAX Technology Inc. (“X-VAX”), a biotechnology company developing vaccines against pathogens acquired by mucosal infection such as herpes, since September 2019. She served as Chief Regulatory and Preclinical Development Officer at X-VAX from September 2018 to September 2019. Dr. Kahn has also been the president of Clare Kahn Pharma Consulting LLC, through which she provides consulting services on regulatory strategy since July 2016. Dr. Kahn was previously Vice President, Worldwide Regulatory Strategy, Global Innovative Pharma at Pfizer from January 2014 to June 2016 and Vice President, Worldwide Regulatory Strategy, Specialty Care Business at Pfizer from June 2010 to December 2013. Prior to Pfizer, she was Vice President of Regulatory Affairs for a variety of therapeutic areas including cardiovascular, metabolic, urology, oncology and vaccines at GlaxoSmithKline from 1999 to 2010. Dr. Kahn has a Ph.D. in Biochemical Pharmacology from The Royal Postgraduate Medical School, London and served as Assistant Professor of Pharmacology and of Pathology and Laboratory Medicine at The University of Pennsylvania from 1981 to 1985. Dr. Kahn is qualified to serve on our Board of Directors because of her extensive leadership experience and her experience working in the healthcare sector. Adam Stone has served as a member of our Board of Directors since November 2015. Mr. Stone is currently the Chief Investment Officer of Perceptive Advisors, a life sciences focused investing firm, where he has worked since 2006. Since July 2021 and February 2021, respectively, Mr. Stone has served as a director and Chief Executive Officer Perceptive Capital Solutions Corp. Mr. Stone is currently a member of the Board of Directors of Immatics N.V., a public biopharmaceutical company, and LianBio and Xontogency LLC, both private companies, and he previously served as a member of the Board of Directors of Renovia Inc. and Prometheus Biosciences, Inc. Mr. Stone received a B.A. in molecular biology from Princeton University. Mr. Stone is qualified to serve on our Board of Directors because of his extensive experience developing early-stage biotech and healthcare companies. Lynne Sullivan has served as a member of our Board of Directors since November 2015. Ms. Sullivan served as the Chief Financial Officer for UNITY Biotechnology, Inc., a biotechnology company, from August 2020 to July 2025. Prior to that, Ms. Sullivan served as the Chief Financial Officer for Compass Therapeutics, LLC (“Compass”), a biotechnology company, from December 2018 to August 2019. Prior to Compass, Ms. Sullivan served as Biogen Inc.’s senior vice president of Finance from 2016 to December 2018, where she also served as vice president of Tax and Corporate Finance from February 2015 to March 2016 and vice president of Tax from April 2008 to February 2015. Ms. Sullivan previously served as a member of the Board of Directors of Inozyme Pharma, Inc., a public biopharmaceutical company, and BiomX Inc. She received an M.S. in Taxation from Bentley University and a B.S.B.A. from Suffolk University. Ms. Sullivan was a Certified Public Accountant for over 20 years. Ms. Sullivan is qualified to serve on our Board of Directors because of her extensive experience in public accounting and financial expertise and her experience working in the healthcare sector.

  5. 2028 Annual Meeting of Stockholders (Class I)

    Alexander Cumbo has served as our President and Chief Executive Officer and as a director since December 2022. Prior to that, Mr. Cumbo served as the President and Chief Executive Officer and as a director of AavantiBio, Inc. (“AavantiBio”), a gene therapy company, from October 2020 to December 2022, when we acquired AavantiBio. From January 2013 to October 2020, Mr. Cumbo held positions of increasing responsibility at Sarepta Therapeutics, Inc. (“Sarepta”), a precision genetic medicine company, ultimately serving as Executive Vice President, Chief Commercial Officer. From 2011 to 2013, Mr. Cumbo served as Vice President of Sales and Treatment Education for Vertex Pharmaceuticals Incorporated , a biotechnology company (“Vertex”), launching Incivek, a treatment for hepatitis C, and from 2010 to 2011, he served as area director for Vertex. Prior to Vertex, Mr. Cumbo served in multiple commercial roles supporting the HIV, HBV and cardiovascular franchises at Gilead Sciences, Inc., a biopharmaceutical company. Mr. Cumbo has served on the Board of Directors of Climb Bio, Inc. since March 2025, and the Board of Directors of Vor Biopharma Inc. since July 2025. Mr. Cumbo previously served on the Board of Directors of RA Pharmaceuticals, Inc., a clinical stage biopharmaceutical company acquired by UCB, Brussels, from November 2018 to April 2020 and Verve Therapeutics Inc., a biopharmaceutical company acquired by Eli Lilly, from June 2022 to July 2025. Mr. Cumbo received a Bachelor of Science in Laboratory Technology from Auburn University. Mr. Cumbo is qualified to serve on our Board of Directors based on his extensive and broad range of experience in the biopharmaceutical industry and his deep knowledge of our company as our Chief Executive Officer. Ilan Ganot is one of our founders and has served as a member of our Board of Directors since our inception in 2013. He also served as our Chief Executive Officer from 2013 to December 2022 and as our President from June 2018 to December 2022. From December 2022 to December 2023, Mr. Ganot assisted with the transition of his duties to Mr. Cumbo and provided other consulting and advisory services, as requested from time to time by us. Mr. Ganot is currently the Chief Executive Officer and a member of the Board of Alesta Therapeutics, a biotechnology company focused on the development of innovative therapies for rare diseases. Mr. Ganot is also a member of the Board of Directors of Minovia Therapeutics, a biotechnology company. Previously, Mr. Ganot served as an investment banker at JPMorgan Chase & Co., Nomura Securities Co., Ltd., and Lehman Brothers. Mr. Ganot received his MBA from London Business School and holds law and business degrees from Reichman University in Herzliya, Israel. Mr. Ganot also practiced corporate law in Israel and was a Captain in the Israeli Defense Forces. He is qualified to serve on our Board of Directors because of his personal dedication to improving treatments available for Duchenne patients, his extensive leadership experience and his extensive knowledge of our company based on his previous role as our Chief Executive Officer. Sukumar Nagendran, M.D. has served as a member of our Board of Directors since September 2018. Since December 2022, Dr. Nagendran has served as President, Head of Research and Development at Taysha Gene Therapies, Inc., a gene therapy company, and he has served as a member of their Board of Directors since July 2020. Prior to that, he was the Chief Medical Officer and President of Research and Development at Jaguar Gene Therapy, a biotechnology company (“Jaguar”), from February 2020 to December 2022. Prior to Jaguar, Dr. Nagendran was Chief Medical Officer and Senior Vice President of AveXis Inc., a clinical-stage gene therapy company (“AveXis”), from September 2015 to July 2018, prior to the company’s acquisition by Novartis Pharmaceuticals Corporation (“Novartis”). Prior to AveXis, Dr. Nagendran was Vice President of Medical Affairs of Quest Diagnostics, a provider of diagnostic information services, from March 2013 to September 2015. Prior to Quest Diagnostics, Dr. Nagendran held key leadership positions at Pfizer Inc. (“Pfizer”), Novartis, Daiichi Sankyo, and Reata Pharmaceuticals. Prior to moving to the biotech industry, Dr. Nagendran practiced internal medicine, with a focus on diabetes and cardiovascular disease. He is a Mayo Alumni Laureate and founding member of the Robert Wood Johnson Legacy Society. He is also the sponsor for the Fonseca-Nagendran Scholar award at the American Diabetes Association to enhance research in minority populations. Dr. Nagendran currently serves on the Board of Directors of SalioGen Therapeutics. Dr. Nagendran received his undergraduate degree in Biochemistry from Rutgers University and his M.D. from Rutgers Medical School and trained in Internal Medicine at Mayo Clinic, Rochester. Dr. Nagendran is qualified to serve on our Board of Directors because of his extensive leadership experience and his experience working in the healthcare sector.

  6. 2027 Annual Meeting of Stockholders (Class III)

    Martin Freed, M.D., F.A.C.P. has served as a member of our Board of Directors since June 2018. Dr. Freed has served as an independent consultant to several private pharmaceutical, biotechnology, and healthcare companies, specializing in clinical and general pharmaceutical development and clinical and regulatory strategy since February 2015. He co-founded and served as Chief Medical Officer of Civitas Therapeutics, Inc., a biopharmaceutical company acquired by Acorda Therapeutics, Inc., from December 2010 to October 2014, and as Senior Vice President, Clinical Development of Acorda Therapeutics, Inc. from October 2014 to January 2015. He has also served as Chief Medical Officer at Adnexus Therapeutics, Inc. (acquired by Bristol-Myers Squibb) and Vitae Pharmaceuticals, Inc. Dr. Freed spent nearly 14 years at GlaxoSmithKline and its predecessor, SmithKline Beecham Pharmaceuticals or SmithKline Beecham, where he served numerous roles including vice president, clinical development and medical affairs in the metabolism therapeutic area. Dr. Freed currently serves on the Board of Directors for Avilar Therapeutics, Inc. He previously served on the Board of Directors for Sojournix, Inc., Dicerna Pharmaceuticals and Intekrin Therapeutics. Dr. Freed has been Board Certified in Internal Medicine, Nephrology and Clinical Pharmacology. He performed his internal medicine residency at Temple University Hospital and nephrology fellowship at Yale-New Haven Hospital. A Fellow of the American College of Physicians, Dr. Freed received a B.S. with distinction in biology from the University of Delaware and an M.D. from Pennsylvania State University’s College of Medicine. Dr. Freed is qualified to serve on our Board of Directors because of his extensive leadership experience, his public company board experience and his experience working in the healthcare sector. Georgia Keresty, Ph.D., M.PH. has served as a member of our Board of Directors since March 2021. Dr. Keresty served as the Chief Operating Officer at Volnay Therapeutics, a biotechnology start-up company, from March 2023 to November 2024. Prior to this role, Dr. Keresty served as a senior advisor to Takeda R&D in 2021 and was their R&D Chief Operating Officer from 2017 to 2020. From 2003 to 2017 and from 1997 to 1999, she was an executive at Johnson & Johnson. From 1999 to 2003 and from 1983 to 1997, she held roles at Bristol-Myers Squibb Company and Novartis, respectively. Dr. Keresty holds BSc degrees in Chemical Engineering and Computer Science from Clarkson University and Ramapo College of New Jersey, an M.S. degree in Information Systems from Pace University, an MBA in Operations Management from Rutgers University, a Ph.D. in Operations Management from Rutgers University, and an MPH in Global Health Leadership from the University of Southern California. Dr. Keresty currently serves on the Board of Directors of Intellia Therapeutics, Inc. Dr. Keresty previously served on the Board of Directors of Aspen Technology, Inc. and Commissioning Agents, Inc. Dr. Keresty is also an NACD Board Leadership Fellow and Directorship Certified® since September 2020 and earned an NACD CERT Certificate in Cyber-Risk Oversight in January 2024. Dr. Keresty is qualified to serve on our Board of Directors because of her extensive leadership and governance experience, and her experience working in the healthcare sector. Ian F. Smith is Executive Chairman of our Board of Directors and has served as a member of our Board of Directors since April 2020 and served as a consultant to us from February 2020 to December 2021. Mr. Smith is also the Chief Executive Officer and a member of the Board of Directors of Stoke Therapeutics, the Chairman of the Board of Directors of Rivus Pharmaceuticals, Inc., and a member of the Board of Directors of Foghorn Therapeutics Inc., Odyssey Therapeutics, Inc. and Alkeus Pharmaceuticals, Inc., which are all biotechnology companies. He is also a Senior Advisor to Bain Capital Life Sciences. Between 2001 and 2019, Mr. Smith served as Chief Financial Officer and then Chief Operating Officer at Vertex. He received a B.A. with honors in accounting and finance from Manchester Metropolitan University (UK). Mr. Smith is qualified to serve on our Board of Directors because of his more than 25 years of finance and broad operating experience for public companies in the biopharmaceutical industry. PROPOSAL NO. 2—THE RATIFICATION OF THE APPOINTMENT OF ILAN GANOT, ON AN ADVISORY BASIS, TO OUR BOARD OF DIRECTORS AS A CLASS I DIRECTOR TO HOLD OFFICE UNTIL THE 2028 ANNUAL MEETING OF STOCKHOLDERS Our Certificate of Incorporation requires that our Board of Directors be divided into three classes, as nearly equal in number as possible. In accordance with our Certificate of Incorporation and bylaws, our directors may fill existing vacancies (including vacancies as a result of a director resignation) on the Board by appointment and without a vote of the stockholders. In order to ensure that the classes of directors be as nearly equal in number as possible, Ilan Ganot, a then-Class III Director (which class is up for election by our stockholders at the annual meeting of stockholders to be held in 2027), resigned from the Board of Directors effective at 4:00 p.m., Eastern Time, on April 10, 2026 (the “Ganot Resignation”). The Board of Directors, upon the recommendation of the nominating and corporate governance committee, simultaneously with the effectiveness of the Ganot Resignation, appointed Mr. Ganot to the Board of Directors as a Class I Director with a term that expires at the annual meeting of stockholders to be held in 2028. Because Mr. Ganot will move from Class III to Class I and therefore will not stand for re-election by our stockholders at the annual meeting of stockholders to be held in 2027, the nominating and corporate governance committee and the Board of Directors believe that, in keeping with our commitment to good corporate governance practices, it is appropriate for the appointment of Mr. Ganot as a Class I Director to be ratified by the stockholders in an advisory manner at the Annual Meeting. Therefore, the Board of Directors adopted a resolution to have our stockholders vote, on an advisory basis, to ratify the appointment of Mr. Ganot to the Board of Directors as a Class I Director. This Proposal No. 2 is advisory and therefore is not binding on us or the Board of Directors. However, the Board and the nominating and corporate governance committee value the opinions of the stockholders. As such, if a majority of the shares present online or represented by proxy at the Annual Meeting do not approve the ratification of Mr. Ganot’s appointment to the Board of Directors as a Class I Director, the nominating and corporate governance committee will consider whether to ask Mr. Ganot to resign from the Board of Directors. If the nominating and corporate governance committee requests that Mr. Ganot resign from the Board of Directors, and if Mr. Ganot resigns and the Board of Directors accepts such resignation, Mr. Ganot will no longer be a member of the Board of Directors. In that case, the Board of Directors may appoint a replacement to fill the vacancy or decrease the number of directors to eliminate the vacancy. If the Board of Directors rejects such resignation, we will publicly disclose that decision and the rationale behind it. OUR BOARD UNANIMOUSLY RECOMMENDS THAT THE STOCKHOLDERS VOTE “FOR” THE RATIFICATION OF THE APPOINTMENT OF ILAN GANOT, ON AN ADVISORY BASIS, TO THE BOARD OF DIRECTORS AS A CLASS I DIRECTOR TO HOLD OFFICE UNTIL THE 2028 ANNUAL MEETING OF STOCKHOLDERS

  7. Identification and Evaluation of Nominees for Directors

    Identification and Evaluation of Nominees for Directors The nominating and corporate governance committee identifies nominees for director by first evaluating the current members of our Board willing to continue in service. Current members with qualifications and skills that are consistent with the nominating and corporate governance committee’s criteria for Board service and who are willing to continue in service are considered for re-nomination, balancing the value of continuity of service by existing members of our Board with that of obtaining a new perspective or expertise. If any member of our Board does not wish to continue in service or if our Board decides not to re-nominate a member for re-election, the nominating and corporate governance committee will identify a new nominee that meets the criteria above. The committee generally inquires of our Board and members of management for their recommendations. The committee may also review the composition and qualification of the boards of directors of our competitors and may seek input from industry experts or analysts. The nominating and corporate governance committee reviews the qualifications, experience and background of suggested candidates. Final candidates, if other than our current directors, would be interviewed by the members of the nominating and corporate governance committee and by certain of our other independent directors and executive management. In making its determinations, the nominating and corporate governance committee evaluates each individual in the context of our Board as a whole, with the objective of assembling a group that can best contribute to the success of the Company and represent stockholder interests through the exercise of sound judgment. After review and deliberation of all feedback and data, the nominating and corporate governance committee makes its recommendation to our Board. We have not received director candidate recommendations from our stockholders and do not have a formal policy regarding consideration of such recommendations. However, any recommendations received from stockholders will be evaluated in the same manner that potential nominees suggested by Board members, management or other parties are evaluated. We do not intend to treat stockholder recommendations in any manner different from other recommendations. Under our bylaws, stockholders wishing to propose a candidate for director should write to our secretary. In order to give the nominating and corporate governance committee sufficient time to evaluate a recommended candidate and/or include the candidate in our proxy statement for the 2027 annual meeting of stockholders, the recommendation should be received by our secretary at our principal executive offices in accordance with our procedures detailed in the section below entitled “Stockholder Proposals”. Such submissions must state the nominee’s name, together with appropriate biographical information and background materials, and information with respect to the stockholder or group of stockholders making the recommendation, including the number of shares of common stock owned by such stockholder or group of stockholders, as well as other information required by our bylaws. We may require any proposed nominee to furnish such other information as we may reasonably require to determine the eligibility of such proposed nominee to serve as an independent director or that could be material to a reasonable stockholder’s understanding of the independence, or lack thereof, of such proposed nominee.

  8. Non-Employee Director Compensation

    Non-Employee Director Compensation Non-employee director compensation is set by our Board of Directors at the recommendation of our compensation committee. In 2025, the compensation committee retained Radford, an AON Hewitt company, to assist in assessing our non-employee director compensation program and provide recommendations with respect to the compensation program. Under our current director compensation program, we pay our non-employee directors a cash retainer for their service on the Board of Directors and for their service on each committee of which the director is a member. The chairs of each committee receive higher retainers for such service. These fees are payable in arrears in equal semi-annual installments not later than the 15th business day following the end of the second and fourth calendar quarters, provided that the amount of such payment will be prorated for any portion of such semi-annual period that the director is not serving on the Board of Directors, on such committee or in such position. The fees paid to non-employee directors for their service on the Board of Directors and for their service on each committee of the Board of Directors of which the director is a member are as follows:

  9. Non-Employee Director Compensation

    | | Member Annual Fee ($) | Chairperson Incremental Annual Fee ($) | | Board of Directors | 40,000 | 35,000 | | Audit Committee | 10,000 | 10,000 | | Clinical Committee | 7,500 | 7,500 | | Compensation Committee | 6,000 | 6,000 | | Nominating and Corporate Governance Committee | 5,000 | 5,000 |

  10. Non-Employee Director Compensation

    We also reimburse our non-employee directors for reasonable out-of-pocket business expenses incurred in connection with the performance of their duties as directors, including travel expenses in connection with their attendance in person at our Board of Directors and committee meetings. In addition, under our current director compensation program, each new non-employee director elected to our Board of Directors will receive an option to purchase 155,000 shares of our common stock under our Amended and Restated 2020 Equity Incentive Plan, as amended (the “2020 Plan”). Each of these options vests in equal annual installments over a three-year period measured from the date of grant, subject to the director’s continued service as a director. Further, on the date of our annual meeting of stockholders, each non-employee director that has served on our Board of Directors for at least six months prior to such annual meeting will receive an option to purchase 77,500 shares of our common stock under our 2020 Plan. Each of these options vests in full on the earlier to occur of the one-year anniversary of the grant date and immediately prior to our first annual meeting of stockholders occurring after the grant date, subject to the director’s continued service as a director. All options granted to our non-employee directors under our director compensation program will be issued at exercise prices equal to the fair market value of our common stock on the date of grant and will become exercisable in full in the event of a change in control. This program is intended to provide compensation for our non-employee directors in a manner that enables us to attract and retain outstanding director candidates and reflects the substantial time commitment necessary to oversee our affairs. We also seek to align the interests of our directors and our stockholders, and we have chosen to do so by compensating our non-employee directors with a mix of cash and equity-based compensation. The table below shows the compensation paid to our non-employee directors during 2025.

  11. Non-Employee Director Compensation

    | Name | Fees Earned or Paid in Cash ($) | Option Awards ($) (1)(2) | Stock Awards ($)(3) | All Other Compensation ($) | Total ($) | | Ian Smith | 75,000 | 372,682(4) | 75,001(5) | — | 522,683 | | Martin Freed, M.D., F.A.C.P. | 60,553 | 297,685(6) | — | — | 358,238 | | Ilan Ganot | 40,000 | 297,685(6) | — | — | 337,685 | | Clare Kahn, Ph.D. | 52,053 | 297,685(6) | — | — | 349,738 | | Georgia Keresty, Ph.D., M.PH. | 59,990 | 297,685(6) | — | — | 357,675 | | Sukumar Nagendran, M.D. | 53,053 | 297,685(6) | — | — | 350,738 | | Adam Stone | 57,990 | 297,685(6) | — | — | 355,675 | | Lynne Sullivan | 62,321 | 297,685(6) | — | — | 360,006 |

  12. Non-Employee Director Compensation

    (1) The amounts in this column represent the aggregate grant date fair value of the options granted to the non-employee directors as computed in accordance with Financial Accounting Standards Board Accounting Standards Codification Topic 718 (“FASB ASC Topic 718”). The assumptions used in calculating the grant date fair value of the options are set forth in Note 9 to our audited consolidated financial statements in our Annual Report on Form 10-K for the year ended December 31, 2025. As of December 31, 2025, our non-employee directors held options to purchase shares of our common stock as follows: Mr. Smith: 303,554 shares; Dr. Freed: 142,930 shares; Mr. Ganot: 227,814 shares; Dr. Kahn: 139,932 shares; Dr. Keresty: 137,266 shares; Dr. Nagendran: 141,265 shares; Mr. Stone: 139,932 shares; and Ms. Sullivan: 139,932 shares. The amount in this column represents the aggregate grant date fair value of the restricted stock units (“RSUs”) as computed in accordance with FASB ASC Topic 718. The assumptions used in calculating the grant date fair value of the award are set forth in Note 9 to our audited consolidated financial statements in our Annual Report on Form 10-K for the year ended December 31, 2025. As of December 31, 2025, our non-employee directors held RSUs with respect to shares of our common stock as follows: Mr. Smith: 4,573 RSUs and Mr. Ganot: 3,884 RSUs. (4) Consists of (i) an option to purchase 22,148 shares of our common stock granted on January 6, 2025 in respect of his services as Executive Chairman and (ii) an option to purchase 77,500 shares of our common stock granted on June 12, 2025 in accordance with our non-employee director compensation program. (5) Consists of 18,293 RSUs granted on January 6, 2025 in respect of his services as Executive Chairman. (6) Consists of an option to purchase 77,500 shares of our common stock granted on June 12, 2025 in accordance with our non-employee director compensation program. In respect of his services as Executive Chairman of our Board of Directors, on January 2, 2026, we granted Mr. Smith an option to purchase 18,012 shares of our common stock and 13,761 RSUs. Annie Ganot, who is the wife of Ilan Ganot and one of our co-founders, serves as our Senior Vice President, Patient Advocacy. The compensation she receives in connection with such service is set forth below under “Certain Relationships and Related Person Transactions—Related Person Transactions.” During 2025, we did not provide any compensation to Mr. Cumbo, our President and Chief Executive Officer, for his service as a member of our Board of Directors. Mr. Cumbo’s compensation for his service as an executive officer is set forth below under “Executive Compensation—2025 Summary Compensation Table.” REPORT OF THE AUDIT COMMITTEE OF THE BOARD OF SOLID BIOSCIENCES INC. The audit committee is appointed by the Board to assist the Board in fulfilling its oversight responsibilities with respect to (1) the integrity of our financial statements and financial reporting process and systems of internal controls regarding finance, accounting, and compliance with legal and regulatory requirements, (2) the qualifications, independence, and performance of our independent registered public accounting firm, (3) the performance of our internal audit function, if any, and (4) other matters as set forth in the charter of the audit committee approved by the Board. Management is responsible for the preparation of the Company’s financial statements and the financial reporting process, including its system of internal control over financial reporting and its disclosure controls and procedures. The independent registered public accounting firm is responsible for performing an audit of the Company’s financial statements in accordance with the standards of the Public Company Accounting Oversight Board (“PCAOB”) and issuing a report thereon. The audit committee’s responsibility is to monitor and oversee these processes. In connection with these responsibilities, the audit committee reviewed and discussed with management and the independent registered public accounting firm the audited consolidated financial statements of the Company for the fiscal year ended December 31, 2025. The audit committee also discussed with the independent registered public accounting firm the matters required to be discussed by the applicable requirements of the PCAOB and SEC. In addition, the audit committee received written communications from the independent registered public accounting firm confirming their independence as required by the applicable requirements of the PCAOB and has discussed with the independent registered public accounting firm their independence. Based on the reviews and discussions referred to above, the audit committee recommended to the Board that the audited consolidated financial statements of the Company be included in its Annual Report on Form 10-K for the fiscal year ended December 31, 2025 that was filed with the SEC. THE AUDIT COMMITTEE OF THE BOARD OF DIRECTORS OF SOLID BIOSCIENCES INC. Lynne Sullivan, Chairperson Georgia Keresty, Ph.D. Adam Stone

  13. 2025 Summary Compensation Table

    2025 Summary Compensation Table The following table contains information about the compensation paid to or earned by each of our Named Executive Officers for the years ended December 31, 2025 and 2024.

  14. 2025 Summary Compensation Table

    | Name and Principal Position | Year | Salary ($) | Bonus ($)(1) | Stock Awards ($)(2) | Option Awards ($)(3) | All Other Compensation ($)(4) | Total ($) | | Alexander Cumbo, | 2025 | 650,988 | 449,182 | 2,318,275 | 1,792,397 | 12,600 | 5,223,442 | | President and Chief Executive Officer | 2024 | 608,400 | 334,620 | 2,215,183 | 1,699,286 | 12,420 | 4,869,909 | | Gabriel Brooks, M.D., | 2025 | 502,164 | 259,870 | 798,634 | 756,790 | 10,698 | 2,328,156 | | Chief Medical Officer | 2024 | 468,000 | 187,200 | 785,378 | 618,887 | 11,907 | 2,071,372 | | David Tyronne Howton, | 2025 | 513,422 | 265,696 | 1,000,488 | 796,621 | 12,600 | 2,588,827 | | Chief Operating Officer and Secretary | 2024 | 473,200 | 189,280 | 1,057,038 | 831,076 | 12,420 | 2,563,014 |

  15. 2025 Summary Compensation Table

    (1) Except where noted otherwise, represents annual cash bonuses earned in the calendar year and paid to the Named Executive Officers after the completion of each calendar year at the discretion of our Board of Directors. (2) The amounts in this column represent the aggregate grant date fair value of the RSUs granted to the Named Executive Officers in 2025 and performance-based restricted stock unit awards (“PSUs”) and RSUs granted to the Named Executive Officers in 2024 as computed in accordance with FASB ASC Topic 718. The assumptions used in calculating the grant date fair value of the PSUs and RSUs are set forth in Note 9 to our audited consolidated financial statements in our Annual Report on Form 10-K for the year ended December 31, 2025. The grant date fair value of the PSUs granted in 2024 included in this column reflects the value of the award based on the probable outcomes of performance conditions. The grant date fair value assuming the highest level of performance conditions being achieved for these PSUs granted in 2024 is $5,088,807, $1,767,764, and $2,383,403 for Mr. Cumbo, Dr. Brooks, and Mr. Howton, respectively. (3) The amounts in this column represent the aggregate grant date fair value of the options granted to the Named Executive Officers in the respective calendars years as computed in accordance with FASB ASC Topic 718. The assumptions used in calculating the grant date fair value of the options are set forth in Note 9 to our audited consolidated financial statements in our Annual Report on Form 10-K for the year ended December 31, 2025. (4) Reflects a matching contribution under our 401(k) plan.

  16. Outstanding Equity Awards at 2025 Fiscal Year-End

    Outstanding Equity Awards at 2025 Fiscal Year-End The following table sets forth information regarding equity awards held by our Named Executive Officers as of December 31, 2025.

  17. Outstanding Equity Awards at 2025 Fiscal Year-End

    | | Option Awards | | | | Stock Awards | | | | | Name | Number of securities underlying unexercised options (#) exercisable | Number of securities underlying unexercised options (#) unexercisable | Option exercise price ($) | Option expiration date | Number of shares of stock that have not vested (#) | Market value of shares of stock that have not vested ($)(1) | Equity incentive plan awards: number of unearned shares, units or other rights that have not vested (#) | Equity incentive plan awards: market or payout value of unearned shares, units or other rights that have not vested ($)(1) | | Alexander Cumbo | 171,678 | 57,222(2) | 6.77 | 12/02/2032 | | | | | | | 110,113 | 130,137(3) | 7.85 | 2/13/2034 | | | | | | | | 337,500(4) | 6.17 | 8/14/2035 | | | | | | | | | | | 28,613(5) | 161,377(5) | | | | | | | | | 90,094(6) | 508,130(6) | | | | | | | | | 401,600(7) | 2,265,024(7) | | | | | | | | | 168,750(8) | 951,750(8) | | | | | | | | | | | 508,203(9) | 2,866,265(9) | | Gabriel Brooks | 42,254 | 35,746(10) | 2.15 | 10/18/2033 | | | | | | | 40,106 | 47,394(3) | 7.85 | 2/13/2034 | | | | | | | | 142,500(4) | 6.17 | 8/14/2035 | | | | | | | | | | | 19,500(11) | 109,980(11) | | | | | | | | | 32,813(6) | 185,065(6) | | | | | | | | | 112,900(7) | 636,756(7) | | | | | | | | | 71,250(8) | 401,850(8) | | | | | | | | | | | 176,542(9) | 995,697(9) | | David Tyronne Howton | 78,313 | 26,097(2) | 6.77 | 12/02/2032 | | | | | | | 53,856 | 63,644(3) | 7.85 | 2/13/2034 | | | | | | | | 150,000(4) | 6.17 | 8/14/2035 | | | | | | | | | | | 13,052(5) | 73,613(5) | | | | | | | | | 44,063(6) | 248,515(6) | | | | | | | | | 169,100(7) | 953,724(7) | | | | | | | | | 75,000(8) | 423,000(8) | | | | | | | | | | | 238,024(9) | 1,342,455(9) |

  18. Outstanding Equity Awards at 2025 Fiscal Year-End

    (1) Based on the $5.64 closing sale price of our common stock on December 31, 2025 as reported by the Nasdaq Global Select Market. (2) This option was granted on December 2, 2022 as an inducement grant. The option is subject to vesting with respect to 25% of the shares underlying the option on the first anniversary of the grant date and as to an additional 2.0833% of the original number of shares underlying the option monthly thereafter through the fourth anniversary of the grant date. (3) This option was granted on February 13, 2024 under the 2020 Plan and is subject to vesting with respect to 25% of the shares underlying the option on the first anniversary of the grant date and as to an additional 2.0833% of the original number of shares underlying the option monthly thereafter through the fourth anniversary of the grant date. (4) This option was granted on August 14, 2025 under the 2020 Plan and is subject to vesting with respect to 50% of the original number of shares vesting on the second anniversary of the grant date and 25% of the original number of shares annually thereafter until the fourth anniversary of the grant date. (5) These RSUs were granted on December 2, 2022 as inducement grants. The RSUs vest in equal annual installments over a term of four years from the date of grant. (6) These RSUs were granted on February 13, 2024 under the 2020 Plan and vest in equal annual installments over a term of four years from the date of grant. (7) These RSUs were granted on January 31, 2025 under the 2020 Plan and vest in equal annual installments over a term of four years from the date of grant These RSUs were granted on August 14, 2025 under the 2020 Plan and vest with respect to 50% of the original number of shares vesting on the second anniversary of the grant date and 25% of the original number of shares annually thereafter until the fourth anniversary of the grant date. These PSUs were granted on June 11, 2024 under the 2020 Plan. The PSUs provide for the vesting of 25% of the target number of underlying RSUs granted upon the achievement of each of four independent performance milestones. The performance milestones are tied to the achievement of certain business objectives and are non-market and non-financial in nature. In the first quarter of 2026, the Board determined that two performance conditions under the PSUs were achieved. For more information, the “Narrative to the Summary Compensation Table” above. The Board will determine whether the remaining two performance conditions have been satisfied and the remaining number of units that may vest on the 2027 Evaluation Date, which will occur in the first quarter of 2027. The number in the table assumes that performance conditions relating to 25% and an additional 50% of target PSUs will be achieved on the 2026 Evaluation Date and 2027 Evaluation Date, respectively. (10) This option was granted on October 18, 2023 under the 2020 Plan and is subject to vesting with respect to 25% of the shares underlying the option on the first anniversary of the grant date and as to an additional 2.0833% of the original number of shares underlying the option monthly thereafter through the fourth anniversary of the grant date. (11) These RSUs were granted on October 18, 2023 under the 2020 Plan and vest in equal annual installments over a term of four years from the date of grant.

  19. Pay Versus Performance Disclosure

    Pay Versus Performance Disclosure In accordance with rules adopted by the Securities and Exchange Commission pursuant to the Dodd-Frank Wall Street Reform and Consumer Protection Act of 2010, we provide the following disclosure regarding executive compensation for our principal executive officer (“PEO”) and other named executive officers (the “Non-PEO NEOs”) and Company performance for the fiscal years listed below. The compensation committee did not consider the pay versus performance disclosure below in making its compensation decisions for any of the years shown.

  20. Pay Versus Performance Disclosure

    | Year | Summary Compensation Table Total for PEO¹ ($) | Compensation Actually Paid to PEO1,2,3 ($) | Average Summary Compensation Table Total for Non-PEO NEOs1 ($) | Average Compensation Actually Paid to Non-PEO NEOs1,2,3 ($) | Value of Initial Fixed $100 Investment based on Total Shareholder Return4 ($) | Net Income ($ Millions) | | 2025 | 5,223,442 | 7,791,053 | 2,458,492 | 3,484,643 | 104.83 | (174.33) | | 2024 | 4,869,909 | 3,451,845 | 2,317,193 | 1,646,659 | 74.35 | (124.70) | | 2023 | 918,630 | 862,406 | 1,184,878 | 1,051,672 | 114.13 | (96.02) |

  21. Pay Versus Performance Disclosure

    Alexander Cumbo was our PEO for all years presented. The individuals comprising the Non-PEO NEOs for each year presented are listed below.

  22. Pay Versus Performance Disclosure

    | 2023 | 2024 | 2025 | | Kevin Tan | Gabriel Brooks, M.D. | Gabriel Brooks, M.D. | | Carl Morris, Ph.D. | David Tyronne Howton | David Tyronne Howton | | David Tyronne Howton | | |

  23. Pay Versus Performance Disclosure

    2. The amounts shown for Compensation Actually Paid have been calculated in accordance with Item 402(v) of Regulation S-K and do not reflect the actual amount of compensation actually earned, realized, or received by the Company’s NEOs during the applicable years. These amounts reflect the Summary Compensation Table Total with certain adjustments as described in footnote 3 below. 3. Compensation Actually Paid reflects the exclusions and inclusions of certain amounts for the PEO and the Non-PEO NEOs as set forth below. Equity values are calculated in accordance with FASB ASC Topic 718. Amounts in the Exclusion of Stock Awards and Option Awards column are the totals from the Stock Awards and Option Awards columns set forth in the Summary Compensation Table (the amounts for the Non-PEO NEOs are averages for the group of Non-PEO NEOs).

  24. Pay Versus Performance Disclosure

    | Year | Summary Compensation Table Total for PEO ($) | Exclusion of Stock Awards and Option Awards for PEO ($) | Inclusion of Equity Values for PEO ($) | Compensation Actually Paid to PEO ($) | | 2025 | 5,223,442 | (4,110,672) | 6,678,283 | 7,791,053 |

  25. Pay Versus Performance Disclosure

    | Year | Average Summary Compensation Table Total for Non-PEO NEOs ($) | Average Exclusion of Stock Awards and Option Awards for Non-PEO NEOs ($) | Average Inclusion of Equity Values for Non-PEO NEOs ($) | Average Compensation Actually Paid to Non-PEO NEOs ($) | | 2025 | 2,458,492 | (1,676,267) | 2,702,418 | 3,484,643 |

  26. Pay Versus Performance Disclosure

    The amounts in the Inclusion of Equity Values in the tables above are derived from the amounts set forth in the following tables:

  27. Pay Versus Performance Disclosure

    | Year | Year-End Fair Value of Equity Awards Granted During Year That Remained Outstanding and Unvested as of Last Day of Year for PEO ($) | Change in Fair Value from Last Day of Prior Year to Last Day of Year of Outstanding and Unvested Equity Awards for PEO ($) | Vesting-Date Fair Value of Equity Awards Granted During Year that Vested During Year for PEO ($) | Change in Fair Value from Last Day of Prior Year to Vesting Date of Unvested Equity Awards that Vested During Year for PEO ($) | Fair Value at Last Day of Prior Year of Equity Awards Forfeited During Year for PEO ($) | Total - Inclusion of Equity Values for PEO ($) | | 2025 | 4,845,047 | 1,799,848 | — | 33,388 | — | 6,678,283 |

  28. Pay Versus Performance Disclosure

    | Year | Average Year-End Fair Value of Equity Awards Granted During Year That Remained Outstanding and Unvested as of Last Day of Year for Non-PEO NEOs ($) | Average Change in Fair Value from Last Day of Prior Year to Last Day of Year of Outstanding and Unvested Equity Awards for Non-PEO NEOs ($) | Average Vesting- Date Fair Value of Equity Awards Granted During Year that Vested During Year for Non-PEO NEOs ($) | Average Change in Fair Value from Last Day of Prior Year to Vesting Date of Unvested Equity Awards that Vested During Year for Non-PEO NEOs ($) | Average Fair Value at Last Day of Prior Year of Equity Awards Forfeited During Year for Non-PEO NEOs ($) | Total - Average Inclusion of Equity Values for Non-PEO NEOs ($) | | 2025 | 1,913,250 | 766,463 | — | 22,705 | — | 2,702,418 |

  29. Pay Versus Performance Disclosure

    The amounts shown assume $100 was invested for the period starting December 31, 2022, through the end of the listed year in the Company. Historical stock performance is not necessarily indicative of future stock performance. Description of Relationship Between PEO and Non-PEO NEO Compensation Actually Paid and Company Total Shareholder Return (“TSR”) The following chart sets forth the relationship between Compensation Actually Paid to our PEOs, the average of Compensation Actually Paid to our Non-PEO NEOs and the Company’s cumulative TSR over the three most recently completed fiscal years. Description of Relationship Between PEO and Non-PEO NEO Compensation Actually Paid and Net (Loss) Income The following chart sets forth the relationship between Compensation Actually Paid to our PEOs, the average of Compensation Actually Paid to our Non-PEO NEOs, and our Net (Loss) Income during the three most recently completed fiscal years.