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Item 9A. Controls and Procedures

2026-03-23 compared with 2025-03-31 · 217 added, 922 removed, 741 unchanged (61% of the section changed)

28 unchanged sentences

Rule 10b5-1 Trading Plans

During the fiscal quarter ended on December 31, 2024, none of our directors and officers (as defined in Rule 16a-1(f) under the Exchange Act) adopted , modified or terminated a “Rule 10b5-1 trading arrangement” or “non-Rule 10b5-1 trading arrangement,” as those terms are defined in Item 408(a) of Regulation S-K, except as described in the table below:

Name and Title

Duration of Trading Arrangements (1)

Rule 10b5-1 Trading Arrangement?

Aggregate Number of Securities Subject to Trading Arrangement

Steven Nichtberger

Chief Executive Officer

Terminate (2)

October 18, 2024

July 8, 2024 - July

Up to 350,000 shares to be sold

Steven Nichtberger

Chief Executive Officer

October 18, 2024

February 16, 2025 – July 27, 2026

Up to 350,000 shares to be sold

Gwendolyn Binder

President of Science and Technology

November 21, 2024

February 20, 2024 – February 21, 2025

Up to 100,756 shares to be sold

Gwendolyn Binder

President of Science and Technology

December 18, 2024

March 27, 2025 to December 12, 2025

Up to 100,756 shares to be sold

* Denotes whether the trading plan is intended, when adopted, to satisfy the affirmative defense of Rule 10b5-1(c).

(1) Except as indicated by footnote, each trading arrangement permitted or permits transactions through and including the earlier to occur of (a) the completion of all purchases or sales or (b) the date listed in the table.

(2) Represents the modification, as described in Rule 10b5-1(c)(1)(iv) under the Exchange Act, of a written trading arrangement adopted on November 9, 2023 that was intended to satisfy the affirmative defense conditions of Rule 10b5-1(c) under the Exchange Act.

During the fiscal quarter ended on December 31, 2025, none of our directors and officers (as defined in Rule 16a-1(f) under the Exchange Act) adopted , modified or terminated a “Rule 10b5-1 trading arrangement” or “non-Rule 10b5-1 trading arrangement,” as those terms are defined in Item 408(a) of Regulation S-K.

Disclosure Regarding Foreign Jurisdictions that Prevent Inspections.

Not applicable.

Directors, Executive Off icers and Corporate Governance.

The following table sets forth information about our directors and executive officers as of March 27, 2025.

Positions and Offices Held with Cabaletta

Officer/Director

Class and Year in Which Term Will Expire

Executive Officers

Steven Nichtberger, M.D.

Chief Executive Officer, President, Chairman of the Board of Directors and Director

Class III—2025

Binder, Ph.D.

President, Science and Technology

Anup Marda, MBA

Chief Financial Officer

Chang, M.D., M.P.H.

Chief Medical Officer

Michael Gerard, J.D.

General Counsel and Secretary

Arun Das, M.D.

Chief Business Officer

Non-Employee Directors

Mark Simon, MBA (1)(2)(3)

Class III—2025

Scott Brun, M.D.

Shawn Tomasello, MBA (2)

Catherine Bollard, MBChB, M.D.

Class II—2027

Richard Henriques, MBA (1)(2)

Class II—2027

(1) Member of the Audit Committee.

(2) Member of the Compensation Committee.

(3) Member of the Nominating and Corporate Governance Committee.

Executive Officers

Steven Nichtberger, M.D.

Nichtberger has served as our Chief Executive Officer, President and Chairman of our board of directors since our founding in 2017.

He is also a Professor of Professional Practice in the Vagelos LSM program and adjunct professor at The Wharton School of the University of Pennsylvania in addition to being a member of the board of directors of the BioAdvance Greenhouse Fund.

Previously, Dr.

Nichtberger served as president, chief executive officer, and a member of the board of directors of Tengion, Inc.

from 2004 to 2011.

In 2008, his leadership was recognized nationally with the National Ernst & Young Entrepreneur of the Year Award for emerging companies.

Earlier in his career, Dr.

Nichtberger served as the head of global marketing for Merck and in various commercial operating roles at the company from 1995 to 2003.

He has previously served as a member of the boards of directors of the Alliance for Regenerative Medicine (as a founding member), Pennsylvania Bio (including as chairman), and Biotechnology Industry Organization.

From 2008 to 2019, he was a member of the board of overseers for the School of Arts & Sciences at the University of Pennsylvania.

Nichtberger received his M.D.

from the State University of New York at Buffalo, his B.S.

from The Wharton School at the University of Pennsylvania and his B.A.

from the University of Pennsylvania.

He completed internship, residency and fellowship in the Department of Medicine and the Division of Cardiology of the Mount Sinai Medical Center in New York.

We believe Dr.

Nichtberger is qualified to serve as a member and Chairman of our board of directors because of his scientific and medical background as well as his corporate leadership experience.

Binder, Ph.D.

Binder joined our company in February 2019 as our Executive Vice President, Science and Technology and was appointed President, Science and Technology in January 2022.

Binder is an R&D executive with specialized expertise in the discovery and early clinical development and optimization of engineered T cell therapies.

Prior to joining Cabaletta, Dr.

Binder was the Chief Technology Officer of Adaptimmune Therapeutics Plc from March 2016 to January 2019, where she ultimately led the research team focusing on understanding mechanisms of tumor response and resistance and translating this understanding to next generation products and clinical study designs.

In prior roles, from March 2011 to February 2016, she established and led the translational research group, in addition to the manufacturing and quality teams including oversight of the buildout of an in-house manufacturing facility.

Earlier in her career, Dr.

Binder served as Director of Operations for the Translational Research Program at the University of Pennsylvania, where she where she progressed multiple investigational new drug submissions for novel engineered T-cell therapies in HIV and oncology, including the CD19 CAR IND acquired by Novartis (now Kymriah), the first human gene editing IND, and three TCR engineered T cell therapy studies in oncology and HIV.

Prior to that, she served as the

Director of Scientific Affairs at VIRxSYS Corporation in Gaithersburg Maryland where she supported the development of the first clinical lentiviral vector used in humans, for the application of engineered T cell therapy for HIV.

In addition, Dr.

Binder has served on the Board of Directors of Instil Bio (Nasdaq:

TIL), a clinical-stage biopharmaceutical company focused on developing a pipeline of novel therapies including a lead PD-L1xVEGF bispecific antibody for solid tumors, since July 2020, and as a member of the Scientific Advisory Board for Immatics, which is a publicly traded company developing engineered T cell immunotherapy for cancer, since July 2020.

Binder studied viral immunology and translational research at the Johns Hopkins University in Baltimore, Maryland where she earned a Ph.D.

in Cellular and Molecular Medicine in 2002.

She has authored over 30 publications in the field, including top international journals such as “Science”, and “Nature Medicine”.

She is a recognized leader in the biotechnology sector for the translational and clinical advancement of novel T cell therapies for patients with serious diseases.

Anup Marda, MBA.

Marda joined our company in January 2019 as our Chief Financial Officer.

From April 2001 to January 2019, Mr.

Marda held positions at Bristol-Myers Squibb, including, most recently, as Vice President, Head of Global Corporate Financial Planning & Analysis, and previously as Head of Finance, R&D Operations and Head of Finance, R&D Portfolio Management and Global Medical from 2014 to 2018.

Prior to this, Mr.

Marda held the role of Executive Director, U.S.

Pharmaceuticals from 2012 to 2014 and Assistant Treasurer, Capital Markets from 2008 to 2012.

Marda received his MBA from the Krannert School of Business of Purdue University and his B.Tech in Chemical Engineering from the Indian Institute of Technology Bombay.

Chang, M.D., M.P.H.

Chang joined our company in June 2019 as our Chief Medical Officer.

From June 2015 to May 2019, he was Senior Vice President and Head, Inflammation, Autoimmunity & Neuroscience, or IA&NS, Global Medicines Development at AstraZeneca Pharmaceuticals LP, where he oversaw development projects of both biologics and small molecules in a variety of indications and led the late-stage clinical development organization for IA&NS.

From October 2007 to June 2015, Dr.

Chang served in various positions at GlaxoSmithKline plc, including VP and Head, Immuno-Inflammation, Clinical Development.

While at AstraZeneca and GlaxoSmithKline, he provided leadership in driving the clinical development and registration of the only two products approved for systemic lupus erythematosus in the US in over 60 years.

He received his M.D.

from New York University School of Medicine, his M.P.H.

from Emory University and his B.S.

from Yale University.

Chang completed his internship and residency in internal medicine at the New York Hospital—Cornell University Medical Center and fellowship in rheumatology at the Hospital for Special Surgery—Cornell University Medical Center.

Michael Gerard, J.D.

Gerard joined our company in September 2021 as our General Counsel and Secretary.

Prior to joining Cabaletta, Mr.

Gerard served as Associate General Counsel of Spark Therapeutics, Inc., or Spark, from September 2020 to August 2021.

Prior to Spark, Mr.

Gerard served in various legal roles at Sandoz, Inc., a division of the Novartis Group, beginning in 2013, with the most recent role being Executive Director, Associate General Counsel, Business Development and Licensing, Strategy and Portfolio.

Earlier in his career, Mr.

Gerard served as Assistant General Counsel at Aramark and as a litigator at the law firms of Morrison & Foerster, LLP and K&L Gates, LLP in New York.

Gerard received a B.A.

in Political Science from the University of Michigan, Ann Arbor and a J.D.

from Cornell Law School.

Arun Das, M.D.

Das joined our company in July 2019 after serving as a consultant to the company since 2017, and served in several roles, most recently Executive Director of New Product Planning and Business Development, prior to being appointed Chief Business Officer in January 2022.

He is also a Lecturer in the Health Care Management Department at the Wharton School of the University of Pennsylvania.

Prior to joining Cabaletta, Dr.

Das was a resident physician in General Pediatrics at the Children’s Hospital of Philadelphia from June 2018 to June 2019.

Previously, he was an investment banking analyst in the healthcare group at Goldman Sachs from 2010 to 2012.

In addition, Dr.

Das has spent multiple years consulting in business development and operations for several start-ups in the biotechnology space.

Das received his M.D.

from Johns Hopkins University School of Medicine and a B.A.

dual degree from the University of Pennsylvania.

Non-Employee Directors

Mark Simon, MBA .

Simon joined our board of directors in October 2018.

He is a Strategic Advisor since 2020 to the Founder and CEO of Sun Pharmaceutical Industries Ltd., which is the largest pharmaceutical company in India, and a board observer of Sun Pharma Advanced Research Company Ltd., both public companies in India, where Mr.

Simon is focused on accelerating their innovation initiatives.

He is also a consultant to Stifel Nicolaus & Company (NYSE:

SF) and co-founder of Torreya Partners, LLC, a global investment banking firm serving companies in the life sciences industry that Stifel acquired in 2023.

Prior to co-founding Torreya, Mr.

Simon was a managing director and head of life sciences investment banking at Citigroup from 2002 to 2005 where he covered global pharmaceutical companies with a focus on large-capitalization players in the U.S., Europe and Japan.

Prior to Citigroup, Mr.

Simon served as a Managing Director at Robertson Stephens in San Francisco and New York where he was responsible for covering the biotechnology investment banking sector.

During his tenure overseeing the group, he was involved in raising 45% of all biotechnology dollars raised in the U.S.

from 1999-2001.

Prior to joining the investment banking group, Mr.

Simon was a senior biotechnology research analyst at Robertson Stephens, and was named a Wall Street All-Star Analyst for three years in a row.

He began his career at Kidder Peabody as a biotechnology research associate in 1984 and participated in the IPO of Genzyme and the early financings of companies such as Amgen.

Simon currently serves on the boards of directors of several disease advocacy and philanthropic foundations in the oncology, CNS/neuroscience and metabolic areas.

He previously served on the board of directors of Portage Biotech Inc.

PRTG) until April 2024.

Simon received his MBA from Harvard Business School and his B.A.

from Columbia College.

We believe that Mr.

Simon is qualified to serve on our board of directors because of his extensive experience of over 35 years in the life sciences industry and biotechnology and specialty pharmaceutical transactions.

Scott Brun, M.D.

Brun joined our board of directors in June 2021.

Brun is currently President at Gold Mast Consulting, LLC, an advisory firm he founded in 2019 to provide technical advice and strategic guidance related to biopharmaceutical research and development, pipeline portfolio management, commercialization of new therapeutics and strategic communications related to R&D activities.

Brun serves as a Venture Partner at Abingworth LLP and a Senior Medical Advisor to Launch Therapeutics.

Prior to his current roles, Dr.

Brun had two decades of experience in various leadership roles at AbbVie, Inc., including 15 years at the predecessor company, Abbott Laboratories.

The majority of his career has been focused on leading teams and clinical development organizations across a broad variety of therapeutic areas including autoimmune, neurologic, and renal among others.

He was most recently Corporate Vice President of Scientific Affairs and Head of AbbVie Ventures, a corporate venture fund responsible for investment opportunities within AbbVie’s R&D therapeutic areas as well as technology platforms of interest from 2016 to 2019.

Previously, Dr.

Brun served as Corporate Vice President and Head of Pharmaceutical Development at AbbVie from 2013 to 2016.

During his tenure at AbbVie, Dr.

Brun oversaw a global organization with responsibilities for AbbVie’s entire portfolio of early and late-stage clinical pre-registration pipeline compounds as well as marketed compounds within oncology, neurology, immunology, renal, infectious disease, and women’s and men’s health therapeutic areas.

Prior to joining AbbVie, Dr.

Brun spent over 15 years at Abbott Laboratories, where he held positions of increasing leadership responsibility in drug development within the R&D organization.

Brun is a member of the boards of directors of Axial Biotherapeutics, Inc.

and Trishula Therapeutics, Inc., both private, clinical-stage biopharmaceutical companies, Jasper Therapeutics, Inc.

JSPR) a biotechnology company focused on targeting mast cells and stem cells to treat chronic diseases and Forte Biosciences, Inc.

FBRX) a preclinical-stage company focused on autoimmune diseases.

Previously, Dr.

Brun served as a Senior Advisor to the business development team at Horizon Therapeutics plc (Nasdaq:

HZNP) from 2020 to 2023.

Brun received his B.S.

in Biochemistry from the University of Illinois at Urbana-Champaign and earned his M.D.

from the Johns Hopkins University School of Medicine.

He completed his residency in ophthalmology at the Massachusetts Eye and Ear Infirmary, Harvard Medical School.

We believe Dr.

Brun is qualified to serve as a member of our board of directors because of his scientific background and significant experience in clinical and research efforts.

Shawn Tomasello, MBA .

Tomasello joined our Board of Directors in July 2023.

She is currently Chief Executive Officer at CoRegen, Inc., a private company.

Prior to her current role, Ms.

Tomasello served as the Chief Commercial Officer of Kite Pharma, where she oversaw the global commercialization of Yescarta, from 2015 to 2018 including through its acquisition by Gilead for $11.9 billion in October 2017.

She was previously Chief Commercial Officer at Pharmacyclics, where she led commercial and medical affairs activities for Imbruvica®, a first-in-class treatment for hematologic malignancies, from August 2014 until its acquisition by AbbVie for $21.0 billion in August 2015.

Prior to Pharmacyclics, Ms.

Tomasello served in leading commercial roles with multiple major pharmaceutical companies, including Celgene as President of the Americas Hematology and Oncology, where she led the company through five successful product launches encompassing 11 indications and played a critical role in acquisitions.

At Genentech for 14 years prior, Ms.

Tomasello was the National Director of Hematology for Rituxan.

She currently serves on the board of directors of AlloVir, Inc.

ALVR) since March 2022, 4D Molecular Therapeutics Inc.

FDMT) since November 2020 and Centrexion Therapeutics Corp., a private, clinical-stage biopharmaceutical company, since 2017.

She previously served as a board member of TCR2 Therapeutics Inc.

TCRR) until June 2023, Urogen Pharma Ltd (Nasdaq:

URGN) until 2022, Mesoblast, Ltd.

MESO) until August 2022, Clementia Pharmaceuticals, Diplomat Pharmacy, Inc.

until 2020, Abeona Therapeutics (Nasdaq:

ABEO) until 2020, Principia Biopharma until 2020, and Gamida Cell Ltd.

GMDA) until 2024, as well as several private boards.

On such boards, she at various times has served and serves on the Compensation, Nominating and Corporate Governance, Compliance, and Transaction committees.

Tomasello received her B.S.

in Marketing from the University of Cincinnati and her M.B.A.

from Murray State University in Kentucky.

We believe Ms.

Tomasello is qualified to serve as a member of our Board of Directors because of her experience serving in various commercial roles in the life sciences industry.

Catherine Bollard, MBChB, M.D.

Bollard joined our board of directors in April 2019.

She currently serves as Senior Vice President and Chief Research Officer and Director of the Center for Cancer and Immunology Research at the Children’s National Research Institute (CNRI).

She is also a faculty member of the Division of the Blood and Marrow Transplantation at CNH.

Since 2013, Dr.

Bollard has served as a tenured Professor of Pediatrics and Microbiology, Immunology and Tropical Medicine at the George Washington University and is the Associate Center Director (ACD) for Translational Research and Innovation within the George Washington Cancer Center.

Prior to her move in 2013, Dr.

Bollard was Professor of Pediatrics, Medicine and

Immunology at Baylor College of Medicine.

She is a past president of the International Society for Cell Therapy (ISCT), and she served on the Cellular, Tissues and Gene Therapy Advisory Committee of the FDA until 2019.

Bollard chaired the Non-Hodgkin’s Lymphoma Committee of the Children’s Oncology Group from 2012 to 2020 and in 2021 became the President of the Foundation for the Accreditation of Cellular Therapy (FACT).

Bollard was the scientific co-founder of Catamaran Bio, a company developing novel, off-the-shelf chimeric antigen receptor (CAR)-NK cell therapies designed to treat a broad range of cancers and served on its Scientific Advisory Board until 2024.

Bollard was previously on the board of directors and subsequently the Scientific Advisory Board of Mana Therapeutics.

She currently serves on the SAB of Minovia Tx Ltd and serves as Chair of the DSMB for SOBI.

Bollard also serves on the board of directors for Alliance for Regenerative Medicine and a nonprofit organization she co-founded called Access4Kids.

Bollard received her medical degree (MBChB) and her doctor of medicine (MD) from the University of Otago Medical School in New Zealand.

We believe Dr.

Bollard is qualified to serve as a member of our board of directors because of her scientific background and significant experience in clinical and translational research efforts.

Richard Henriques, MBA.

Henriques joined our board of directors in February 2019.

Since 2015, he has been a senior fellow at the Center for High Impact Philanthropy at the University of Pennsylvania, with a focus on impact investing.

From 2010 to 2014, Mr.

Henriques was the Chief Financial Officer of the Bill & Melinda Gates Foundation, where he was responsible for finance and accounting, financial planning and analysis, strategic planning, measurement and evaluation, program related investments and information technology.

From 1981 to 2008, Mr.

Henriques held positions at Merck & Co., Inc., including as Senior Vice President of Finance for Global Human Health, Vice President and Corporate Controller, and Principal Accounting Officer.

Henriques serves on the boards of directors or trustees of the Bucks County Playhouse, International Vaccine Institute, Heritage Conservancy, Delaware Canal 21, Fisherman’s Mark and The Franklin Institute.

Henriques served on the board of directors of Arbutus Biopharma Corporation (Nasdaq:

ABUS) from December 2014 to February 2025.

Henriques received his MBA from the Wharton School of the University of Pennsylvania and a BA from the University of Pennsylvania.

We believe that Mr.

Henriques is qualified to serve as a member of our board of directors because of his extensive corporate leadership experience and expertise in finance and investment management.

Family Relationships and Legal Proceedings

There are no family relationships between or among any of our directors or executive officers.

Our executive officers are appointed by, and serve at the discretion of, our board of 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 above, 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, officers or affiliate, any owner of record or beneficially of more than five percent of any class of our voting securities, or any associate of any such director, officer, affiliate, or security holder is a party adverse to us or any of our subsidiaries or in which any such person has a material interest adverse to us or our subsidiary.

Board Committees

Our board of directors has established an audit committee, a compensation committee, and a nominating and corporate governance committee.

Each of the audit committee, compensation committee, and nominating and corporate governance committee operates under a charter that satisfies the applicable standards of the SEC and Nasdaq.

Our board of directors has also established a science and technology committee, an advisory committee of the board of directors which operates under a charter duly adopted by the board of directors.

Each such committee reviews its respective charter at least annually.

A current copy of the charter for each of the audit committee, compensation committee, nominating and corporate governance committee and science and technology committee is posted on the corporate governance section of our website, www.cabalettabio.com/investors/corporate-governance/governance-documents .

From time to time, our board of directors may establish certain committees for scientific, business or other matters.

Audit Committee

Scott Brun, M.D., Richard Henriques, MBA and Mark Simon, MBA serve on the audit committee, which is chaired by Richard Henriques, MBA.

Our board of directors has determined that each member of the audit committee is “independent” for audit committee purposes as that term is defined in the rules of the SEC and the applicable Nasdaq rules, and each has sufficient knowledge in financial and auditing matters to serve on the audit committee.

Our board of directors has designated Mr.

Henriques as an “audit

committee financial expert,” as defined under the applicable rules of the SEC.

During the fiscal year ended December 31, 2024, the audit committee met seven times.

The 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;

• recommending based upon the audit committee’s review and discussions with management and our independent registered public accounting firm whether our audited financial statements and our related disclosures under the “Management’s Discussion and Analysis” section shall be included in our 2024 Annual Report;

• 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;

• reviewing quarterly earnings releases;

• discussing the Company’s risk assessment and management guidelines, including the Company’s major financial risk exposures, cybersecurity risks and the steps that the Company’s management has taken to monitor and control such exposures and risks.

All audit and non-audit services, other than de minimis non-audit services, to be provided to us by our independent registered public accounting firm must be approved in advance by our audit committee.

Compensation Committee

Richard Henriques, MBA, Mark Simon, MBA and Shawn Tomasello, MBA serve on the compensation committee, which is chaired by Mark Simon, MBA.

Our board of directors has determined that each member of the compensation committee is “independent” as defined in the applicable Nasdaq rules.

During the fiscal year ended December 31, 2024, the compensation committee met four times.

The compensation committee’s responsibilities include:

• annually reviewing and recommending to the board of directors 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 the board of directors the cash compensation of our chief executive officer and (ii) reviewing and approving grants and awards to our chief executive officer under equity-based plans;

• reviewing and approving the compensation of our other executive officers;

• reviewing and establishing our overall management compensation, philosophy, and policy;

• overseeing and administering our compensation and similar plans;

• evaluating and assessing potential and current compensation advisors in accordance with the independence standards identified in the applicable Nasdaq rules;

• reviewing and making recommendations to our board of directors about our policies and procedures for the grant of equity-based awards;

• preparing the compensation committee report required by SEC rules, if and when required, to be included in our annual proxy statement;

• reviewing and discussing annually with management our “Compensation Discussion and Analysis,” if and when required, to be included in our annual proxy statement;

• reviewing and approving the retention or termination of any consulting firm or outside advisor to assist in the evaluation of compensation matters.

Nominating and Corporate Governance Committee

Catherine Bollard, MBChB, M.D., Scott Brun, M.D., and Mark Simon, MBA, serve on the nominating and corporate governance committee, which is chaired by Scott Brun, M.D.

Our board of directors has determined that each member of the nominating and corporate governance committee is “independent” as defined in the applicable Nasdaq rules.

During the fiscal year ended December 31, 2024, the nominating and corporate governance committee met two times.

The nominating and corporate governance committee’s responsibilities include:

• developing and recommending to the board of directors criteria for board and committee membership;

• establishing procedures for identifying and evaluating board of director candidates, including nominees recommended by stockholders;

• reviewing the composition of the 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 the board of directors;

• recommending to the board of directors the persons to be nominated for election as directors and to each of the board’s committees;

• reviewing and discussing with the board of directors corporate succession plans for our chief executive officer and other key officers;

• developing and recommending to the board of directors a code of business conduct and ethics and a set of corporate governance guidelines;

• overseeing the evaluation of our board of directors.

The nominating and corporate governance committee considers candidates for board of directors membership suggested by its members and the chief executive officer.

Additionally, in selecting nominees for directors, the nominating and corporate governance committee will review candidates recommended by stockholders in the same manner and using the same general criteria as candidates recruited by the committee and/or recommended by our board of directors.

Any stockholder who wishes to recommend a candidate for consideration by the committee as a nominee for director should follow the procedures described in our proxy statement under the heading “Stockholder Proposals.” The nominating and corporate governance committee will also consider whether to nominate any person proposed by a stockholder in accordance with the provisions of our bylaws relating to stockholder nominations as described in our proxy statement under the heading “Stockholder Proposals.”

Identifying and Evaluating Director Nominees.

Our board of directors is responsible for filling vacancies on our board of directors and for nominating candidates for election by our stockholders each year in the class of directors whose term expires at the relevant annual meeting.

The board of directors delegates the selection and nomination process to the nominating and corporate governance committee, with the expectation that other members of the board of directors, and of management, will be requested to take part in the process as appropriate.

Generally, the nominating and corporate governance committee identifies candidates for director nominees in consultation with management, through the recommendations submitted by stockholders or through such other methods as the nominating and corporate governance committee deems to be helpful to identify candidates.

Once candidates have been identified, the nominating and corporate governance committee confirms that the candidates meet all of the minimum qualifications for director nominees established by the nominating and corporate governance committee.

The nominating and corporate governance committee may gather information about the candidates through interviews, detailed questionnaires, comprehensive background checks or any other means that the nominating and corporate governance committee deems to be appropriate in the evaluation process.

The nominating and corporate governance committee then meets as a group to discuss and evaluate the qualities and skills of each candidate, both

on an individual basis and taking into account the overall composition and needs of our board of directors.

Based on the results of the evaluation process, the nominating and corporate governance committee recommends candidates for the board of directors’ approval to fill a vacancy or as director nominees for election to the board of directors by our stockholders each year in the class of directors whose term expires at the relevant annual meeting.

Science and Technology Committee

Catherine Bollard, MBChB, M.D., Scott Brun, M.D., and Shawn Tomasello, MBA, serve on the science and technology committee, which is chaired by Catherine Bollard, MBChB, M.D.

The science and technology committee supports Board oversight of the Company’s research and development, manufacturing and supply activities, by providing a forum for review of strategic considerations and issues in such areas, as well as to evaluate relevant emerging technology and advances in the field.

The science and technology committee was formed in July 2023 and held four meetings in during the fiscal year ended December 31, 2024.

Code of Business Conduct and Ethics

We have adopted a written code of business conduct and ethics that applies to our directors, officers and employees, including our principal executive officer, principal financial officer, principal accounting officer or controller, or persons performing similar functions.

A current copy of the code is posted on the corporate governance section of our website, which is located at www.cabalettabio.com/investors/corporate-governance/governance-documents .

If we make any substantive amendments to, or grant any waivers from, the code of business conduct and ethics for any officer or director, we will disclose the nature of such amendment or waiver on our website or in a current report on Form 8-K.

Insider Trading Policies and Procedures

We have adopted an insider trading policy that governs the purchase, sale, and/or other transactions of our securities by our directors, officers, employees and designated consultants that we believe is reasonably designed to promote compliance with applicable insider trading laws, rules and regulations, and listing standards applicable to us.

A copy of our insider trading policy is filed as Exhibit 19.1 to this Annual Report on Form 10-K for the fiscal year ended December 31, 2024.

In addition, with regard to trading in our own securities, it is our policy to comply with the federal securities laws and the applicable exchange listing requirements.

Our insider trading policy prohibits our directors, officers, employees and certain designated consultants, and their affiliated persons, from trading in company securities while in possession of material nonpublic information about our company.

The policy also prohibits tipping (i.e., disclosing material nonpublic information about our company to others who may trade of the basis of that information).

Under our insider trading policy, designated insiders may only trade in company securities at a time when they do not possess material nonpublic information about our company.

We also require our directors, officers and certain other employees to receive approval before trading in company securities.

Our insider trading policy also expressly prohibits short sales;

purchases or sales of puts, calls, or other derivative securities or hedging transactions;

using company securities as collateral in a margin account;

or pledging company securities as collateral for a loan.

Any waiver of the provisions of this policy requires the approval of our Audit Committee.

To date, no such requests have been made or approved.

We have also adopted an additional policy that governs adoption, modification and termination of written securities trading plans, known as Rule 10b5-1 plans, by our directors, executive officers and certain other persons.

Our policy provides that all Rule 10b5-1 plans must comply with SEC rules applicable to the Rule 10b5-1 safe harbor and imposes additional requirements and limitations.

Executiv e Compensation.

Our named executive officers for the year ended December 31, 2024 are:

• Steven Nichtberger, M.D., our President and Chief Executive Officer;

• Gwendolyn Binder, Ph.D., our President, Science and Technology;

Chang, M.D., M.P.H., our Chief Medical Officer.

2024 Summary Compensation Table

The following table presents the compensation awarded to, earned by or paid to each of our named executive officers for the years indicated.

Nichtberger also serves as a member of our board of directors but does not receive any additional compensation for his service as a director.

Option Awards

Incentive Plan

Steven Nichtberger, M.D.

President and Chief Executive Officer

Binder, Ph.D.

President, Science and Technology

Chang, M.D., M.P.H.

Chief Medical Officer

(1) Amounts reflect the grant date fair value of option awards granted in 2024 and 2023 in accordance with the Financial Accounting Standards Board’s Accounting Standards Codification Topic 718, or ASC 718.

Such grant date fair value does not take into account any estimated forfeitures related to service-vesting conditions.

For information regarding assumptions underlying the valuation of equity awards, see Note 10 to our financial statements for the year ended December 31, 2024.

These amounts do not correspond to the actual value that may be recognized by the named executive officers upon vesting of applicable awards.

(2) The amounts represent bonuses earned in 2024 and 2023 and paid in 2025 and 2024, respectively, pursuant to the Company’s cash incentive plan based on the factors described under “Non-Equity Incentive Plan Compensation” below.

(3) Amount includes reimbursements for life insurance premiums.

Narrative to 2024 Summary Compensation Table

Our board of directors and compensation committee review compensation annually for our chief executive officer and his direct reports.

In setting executive base salaries and bonuses, and granting equity incentive awards, our board of directors considers compensation for comparable positions in the market, the historical compensation levels of our executives, individual performance as compared to our expectations and objectives, 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 our company.

We target a general competitive position, based on independent third-party benchmark analytics to inform the mix of compensation of base salary, bonus or long-term incentives.

Our board of directors has historically determined our executives’ compensation.

Our compensation committee typically reviews and discusses management’s proposed compensation with the chief executive officer for all of his direct reports.

Based on those discussions and its discretion, taking into account the factors noted above, the compensation committee determines the compensation for each executive officer other than the chief executive officer.

Our board of directors discusses the compensation committee’s recommendations and ultimately approves the compensation of our chief executive officer without the chief executive officer and chief financial officer present.

In 2024, the compensation committee continued to retain the services of Radford, an AON Hewitt company, as its external compensation consultant and the board of directors and the compensation committee considered Radford’s input on certain compensation matters as they deemed appropriate.

Annual base salary

Each named executive officer’s base salary is a fixed component of annual compensation for performing specific duties and functions, and has been established by our board of directors taking into account each individual’s role, responsibilities, skills, and

Base salaries for our named executive officers are reviewed annually by our compensation committee, typically in connection with our annual performance review process, and adjusted from time to time, based on the recommendation of the compensation committee, to realign salaries with market levels after taking into account individual responsibilities, performance, and experience.

The base salary of each named executive officer in 2024 is noted below:

2024 Base Salary through

February 29, 2024

Base Salary Effective

March 1, 2024

Steven Nichtberger, M.D.

Binder, Ph.D.

Chang, M.D., M.P.H.

Non-Equity Incentive Plan Compensation

Annual cash awards are determined based on company performance, which is assessed based on predetermined annual objectives, and on individual performance.

When determining the individual component of our annual incentive awards, the compensation committee considers each executive’s contributions to the company’s strategic achievements and financial and operational performance.

In addition, the compensation committee considers how each executive demonstrates Cabaletta behaviors.

Each of our named executive officers was eligible to receive a bonus with respect to 2024 as a percentage of base salary listed below, modified by company and individual performance.

2024 Target Bonus Rate

(% of base salary)

Steven Nichtberger, M.D.

Binder, Ph.D.

Chang, M.D., M.P.H.

Company performance was assessed as achievement of 2024 company objectives, including certain clinical development, business development and financial and operational goals and development of a strong team culture.

As a result, the compensation committee recommended and our board of directors approved 2024 company achievement at 108%.

The compensation committee recommended (and/or approved) and the board of directors approved (as applicable, in the instance of the chief executive officer), a further adjustment of bonuses based on the individual achievement of each of the named executive officers, as noted below:

Achievement (%)

Steven Nichtberger, M.D.

Binder, Ph.D.

Chang, M.D., M.P.H.

Long-term equity incentives

Our equity grant program is intended to align the interests of our named executive officers with those of our stockholders and to motivate them to make important contributions to our performance.

In 2024, we granted stock options to each of our named executive officers, as reflected in the “Outstanding Equity Awards at 2024 Fiscal Year End Table” below.

Employment arrangements with our named executive officers

In October 2019, we entered into amended and restated employment agreements with each of our named executive officers.

Each of our named executive officers is employed at will.

Steven Nichtberger, M.D.

Under his amended and restated employment agreement, Dr.

Nichtberger is entitled to an annual base salary, which is subject to review and redetermination by our board of directors or our compensation committee, and he is eligible to receive an annual bonus determined by our board of directors or the compensation committee (subject to the terms of any applicable incentive compensation plan that may be in effect from time to time), with a target amount calculated as a percentage of his annual base salary.

Nichtberger is also eligible to participate in the employee benefit plans available to our employees, subject to the terms of those plans, and is reimbursed for his existing, personal life insurance policy premiums.

Nichtberger’s employment agreement provides that, in the event that his employment is terminated by us without “cause” or by him for “good reason,” then subject to the execution and effectiveness of a separation agreement and release and compliance with his continuing obligations, he will be entitled to receive (i) an amount equal to (x) 12 months of base salary payable on our normal payroll cycle if such termination occurs outside of the period commencing 60 days before and ending 12 months after the occurrence of the first event constituting a “change in control”, or the Change in Control Period, or (y) 1.5 times the sum of his base salary plus his target bonus for the then-current year payable on our or our successor’s normal payroll cycle over 18 months if such termination occurs within Change in Control Period;

(ii) payment of the monthly employer COBRA premium for the same level of group health coverage as in effect for Dr.

Nichtberger on the date of termination for up to (x) 12 months if such termination occurs outside of the Change in Control Period, and (y) 18 months if such termination occurs within the Change in Control Period;

and (iii) full acceleration of all stock options and other stock-based awards held by Dr.

Nichtberger if such termination occurs within the Change in Control Period.

In addition to standard good reason triggers, Dr.

Nichtberger may elect to resign for good reason if within six months following the appointment of a chairperson of the board of directors, Dr.

Nichtberger provides written notice of his reasonable dissatisfaction with such chairperson and the board fails to designate a new chairperson within 30 days of such notice.

In the event of such a resignation for good reason outside of the Change in Control Period, subject to the execution and effectiveness of a separation agreement and release and compliance with his continuing obligations, in addition to the severance benefits described above, all stock options and other stock-based awards held by Dr.

Nichtberger will accelerate and become fully exercisable or nonforfeitable.

The payments and benefits provided to Dr.

Nichtberger under his employment agreement in connection with a sale event may not be eligible for a federal income tax deduction for the company pursuant to Section 280G of the Code.

These payments and benefits also may be subject to an excise tax under Section 4999 of the Code.

If the payments or benefits payable to Dr.

Nichtberger in connection with a sale event would be subject to the excise tax on golden parachutes 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 Dr.

In addition, Dr.

Nichtberger has entered into a non-competition, non-solicitation, confidentiality and assignment agreement with us that contains, among other things, non-competition and non-solicitation provisions that apply during the term of Dr.

Nichtberger’s employment and for 12 months thereafter.

Binder, Ph.D.

Under her amended and restated employment agreement, Dr.

Binder is entitled to an annual base salary, which is subject to review and redetermination by our board of directors or our compensation committee, and she is eligible to earn an annual bonus with a target amount calculated as a percentage of her base salary.

Binder is also eligible to participate in the employee benefit plans available to our employees, subject to the terms of those plans.

Binder’s employment agreement provides that, in the event that her employment is terminated by us without “cause” or by her for “good reason,” then subject to the execution and effectiveness of a separation agreement and release and compliance with her continuing obligations, she will be entitled to receive (i) an amount equal to (x) nine months of base salary payable on our normal payroll cycle if such termination occurs outside of the Change in Control Period or (y) a lump sum in cash in the amount of 1.0 times the sum of her base salary plus her target bonus for the then-current year payable on our or our successor’s normal payroll cycle over 12 months if such termination is occurs within the Change in Control Period;

(ii) payment of the monthly employer COBRA premium for the same level of group health coverage as in effect for Dr.

Binder on the date of termination up to (x) nine months if such termination occurs outside of the Change in Control Period, and (y) 12 months if such termination occurs within the Change in Control Period;

and (iii) full acceleration of all stock options and other stock-based awards subject to time-based vesting held by Dr.

Binder if such termination occurs within the Change in Control Period.

The payments and benefits provided to Dr.

Binder under her employment agreement in connection with a sale event may not be eligible for a federal income tax deduction for the company pursuant to Section 280G of the Code.

These payments and benefits also may be subject to an excise tax under Section 4999 of the Code.

If the payments or benefits payable to Dr.

Binder in connection with a sale event would be subject to the excise tax on golden parachutes 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 such officer.

In addition, Dr.

Binder has entered into a non-competition, non-solicitation, confidentiality and assignment agreement with us that contains, among other things, non-competition and non-solicitation provisions that apply during the term of Dr.

Binder’s employment and for 12 months thereafter.

Chang, M.D., M.P.H.

Under his amended and restated employment agreement, Dr.

Chang is entitled to an annual base salary, which is subject to review and redetermination by our board of directors or our compensation committee, and he is eligible to earn an annual bonus with a target amount calculated as a percentage of his base salary.

Chang is also eligible to participate in the employee benefit plans available to our employees, subject to the terms of those plans.

Chang’s employment agreement provides that, in the event that his employment is terminated by us without “cause” or by him for “good reason,” then subject to the execution and effectiveness of a separation agreement and release and compliance with his continuing obligations, he will be entitled to receive (i) an amount equal to (x) nine months of base salary payable on our normal payroll cycle if such termination occurs outside of the Change in Control Period or (y) a lump sum in cash in the amount of 1.0 times the sum of his base salary plus his target bonus for the then-current year payable on our or our successor’s normal payroll cycle over 12 months if such termination occurs within the Change in Control Period;

(ii) payment of the monthly employer COBRA premium for the same level of group health coverage as in effect for Dr.

Chang on the date of termination up to (x) nine months if such termination occurs outside of the Change in Control Period, and (y) 12 months if such termination occurs outside of the Change in Control Period;

and (iii) full acceleration of all stock options and other stock-based awards subject to time-based vesting held by Dr.

Chang if such termination occurs within the Change in Control Period.

The payments and benefits provided to Dr.

Chang under his employment agreement in connection with a sale event may not be eligible for a federal income tax deduction for the company pursuant to Section 280G of the Code.

These payments and benefits also may be subject to an excise tax under Section 4999 of the Code.

If the payments or benefits payable to Dr.

Chang in connection with a sale event would be subject to the excise tax on golden parachutes 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 such officer.

In addition, Dr.

Chang has entered into a non-competition, non-solicitation, confidentiality and assignment agreement with us that contains, among other things, non-competition and non-solicitation provisions that apply during the term of Dr.

Chang’s employment and for 12 months thereafter.

Outstanding Equity Awards at 2024 Fiscal Year End Table

The following table presents information regarding all outstanding stock awards and stock options held by each of our named executive officers as of December 31, 2024.

Option awards

Number of Securities Underlying Unexercised Options (#) Exercisable

Number of Securities Underlying Unexercised Options (#) Unexercisable

Option Exercise Price ($)

Option Expiration Date

Number of Shares or Units of Stock that Have Not Vested (#)

Market Value of Shares or Units of Stock that Have Not Vested ($)

Steven Nichtberger, M.D.

Binder, Ph.D.

Chang, M.D., M.P.H.

(1) These options vest over four years, with 25% vesting on October 11, 2019, and the remaining shares vesting in 36 equal monthly installments thereafter, subject to a continued service relationship with us.

(2) These options vest over four years, with 25% vesting on October 24, 2020, and the remaining shares vesting in 12 equal quarterly installments thereafter, subject to a continued service relationship with us.

(3) These options vest over four years, with 25% vesting on March 1, 2021, and the remaining shares vesting in 12 equal quarterly installments thereafter, subject to a continued service relationship with us.

(4) These options vest over four years, with 25% vesting on October 11, 2019 and the remaining shares vesting in 12 equal quarterly installments thereafter, subject to a continued service relationship with us.

(5) These options vest over four years, with 25% vesting on August 22, 2020, and the remaining shares vesting in 12 equal quarterly installments thereafter, subject to a continued service relationship with us.

(6) These options vest over four years, with 25% vesting on June 17, 2020, and the remaining shares vesting in 12 equal quarterly installments thereafter, subject to a continued service relationship with us.

(7) These options vest over four years, with 25% vesting on March 1, 2022, and the remaining shares vesting in 12 equal quarterly installments thereafter, subject to a continued service relationship with us.

(8) These options vest over four years, with 25% vesting on January 18, 2023, and the remaining shares vesting in 12 equal quarterly installments thereafter, subject to a continued service relationship with us.

(9) These options vest over four years, with 25% vesting on January 18, 2024, and the remaining shares vesting in 12 equal quarterly installments thereafter, subject to a continued service relationship with us.

(10) These options vest over four years, with 25% vesting on March 1, 2025, and the remaining shares vesting in 12 equal quarterly installments thereafter, subject to a continued service relationship with us.

Additional Narrative Disclosure

401(k) Savings Plan.

We participate in a retirement savings plan, or 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.

employees who are at least 21 years of age 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.

Participant contributions are held in trust as required by law.

An employee’s interest in his or her salary deferral contributions is 100% vested when contributed.

We have the ability to make discretionary contributions under the plan and all eligible employees will receive a Safe Harbor matching contribution up to 4% of eligible pay for the 2024 plan year.

Health and Welfare Benefits .

All of our full-time employees, including our executive officers are eligible to participate in certain medical, disability and life insurance benefit programs offered by us.

We pay the premiums for term life insurance and long-term disability for all of our employees, including our executive officers.

We also provide all employees, including executive officers, with a flexible spending account plan and paid time off benefits including, vacation, sick time and holidays.

We do not sponsor any qualified or non-qualified defined benefit plans for any of our employees or executives.

Compensation Risk Assessment

We believe that although a portion of the compensation provided to our executive officers and other employees is performance-based, our executive compensation program does not encourage excessive or unnecessary risk taking.

Our compensation programs are designed to encourage our executive officers and other employees to remain focused on both short-term and long-term strategic goals, in particular in connection with our pay-for-performance compensation philosophy.

As a result, we do not believe that our compensation programs are reasonably likely to have a material adverse effect on us.

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 when an officer or director is aware of material, non-public information or otherwise is not permitted to trade in Company securities.

Our insider trading policy expressly prohibits short sales and derivative transactions of our stock by our executive officers, directors, employees and certain designated consultants and contractors, including short sales of our securities.

Our insider trading policy expressly prohibits, without the advance approval of our audit committee, purchases or sales of puts, calls, or other derivative securities of the company or any derivative securities that provide the economic equivalent of ownership.

Compensation Recovery Policy (Clawback Policy)

On September 12, 2023, we adopted a Compensation Recovery Policy, or the Clawback Policy, in compliance with the requirements of the Dodd-Frank Act, final SEC rules and applicable Nasdaq listing standards (the “final clawback rules”), which covers our current and former executive officers, including all of our named executive officers.

Under the Clawback Policy, in the event that we are required to prepare a restatement of our previously issued financial statements due to our material noncompliance with any financial reporting requirement under securities laws, we are required to recover (subject to certain limited exceptions described in the Clawback Policy and permitted under the final clawback rules) any cash or equity incentive-based compensation received by any current or former executive officer after the effective date of the Clawback Policy and in the three years prior to the date we are required to restate our financial statements that is in excess of the amount that would have been received based on the restated financial statements.

Compensation Committee Interlocks and Insider Participation

Each of Richard Henriques, Mark Simon and Shawn Tomasello, served on the compensation committee during fiscal year 2024.

No member of the compensation committee has ever been an officer or employee of the Company.

None of our executive officers serve, or have served during the last fiscal year, as a member of the board of directors, compensation committee, or other

board committee performing equivalent functions of any other entity that has one or more executive officers serving as one of our directors or on our compensation committee.

Policy on the Timing of Awards of Options and Other Option-Like Instruments

Our compensation committee has generally granted annual equity awards, including stock option grants to our named executive officers, in the first quarter of each fiscal year, specifically early March.

In addition, new hires receive stock option grants at the time of their hiring.

Eligible employees, including our named executive officers, may voluntarily enroll in our Employee Stock Purchase Plan and receive an option to purchase shares at a discount using payroll deductions accumulated during the prior six months, with purchase dates occurring in May and November.

During 2024, our compensation committee did not take into account any material nonpublic information when determining the timing and terms of equity incentive awards, and we did not time the disclosure of material nonpublic information for the purpose of affecting the value of executive compensation.

During 2024, we did not grant stock options to our named executive officers during any period beginning four business days before and ending one business day after the filing or furnishing of a Form 10-Q, 10-K or 8-K that discloses material nonpublic information.

Please see Item 10 for details regarding corporate governance, including the composition of our compensation committee, as required by Regulation S-K 407(e)(4) and (e)(5).

Director Compensation

The following table presents the total compensation for each person who served as a non-employee member of our board of directors and received compensation for such service during the fiscal year ended December 31, 2024.

Other than as set forth in the table and described more fully below, we did not pay any compensation, make 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 in 2024.

We reimburse members of our board of directors for reasonable travel expenses.

Nichtberger, our Chief Executive Officer and President, did not receive any compensation for his service as a member and Chairman of our board of directors in 2024.

Nichtberger’s compensation for service as an employee for fiscal years 2024 and 2023 is presented in “Executive Compensation—2024 Summary Compensation Table.”

Fees Earned or

Paid In Cash ($)

Option Awards (1)(2)

All Other Compensation

Catherine Bollard, MBChB, M.D.

Scott Brun, M.D.

Richard Henriques, MBA

Mark Simon, MBA

Shawn Tomasello, MBA

(1) Amount shown reflects the grant date fair value of an option award granted during 2024.

The grant date fair value was computed in accordance with Financial Accounting Standards Board Accounting Standards Codification Topic 718, Compensation—Stock Compensation, or FASB ASC Topic 718, disregarding the effect of estimated forfeitures related to service-based vesting.

See Note 10 to the financial statements in our 2024 Annual Report on Form 10-K regarding assumptions we made in determining the fair value of option awards.

(2) As of December 31, 2024, the aggregate number of shares subject to option awards held by our non-employee directors were:

134,428 and Ms.

Tomasello 66,000.

As of December 31, 2024, the aggregate number of unvested shares outstanding held by our non-employee directors were:

22,000 and Ms.

Tomasello 47,667.

Amended and Restated Non-Employee Director Compensation Policy

Under our director compensation policy, we pay our non-employee directors a cash retainer for service on the board of directors and for service on each committee on which the director is a member.

The chairman of each committee receives a higher retainer for such service.

These fees are payable in arrears in four equal quarterly installments on the last day of each quarter, provided that the amount of such payment is prorated for any portion of such quarter that the director is not serving on our board of directors.

The fees paid to non-employee directors for service on the board of directors and for service on each committee of the board of directors on which the director is a member for 2024 are as follows:

Member Annual

Chairperson Annual

Board of Directors

Audit Committee

Compensation Committee

Nominating and Corporate Governance Committee

Science and Technology Committee

In February 2025, we amended our director compensation policy.

Accordingly, the fees paid to non-employee directors for service on the board of directors and for service on each committee of the board of directors on which the director is a member for 2025 are as follows:

Member Annual

Chairperson Annual

Board of Directors

Audit Committee

Compensation Committee

Nominating and Corporate Governance Committee

Science and Technology Committee

We also reimburse our non-employee directors for reasonable out-of-pocket expenses incurred in connection with attending our board of director and committee meetings.

In addition, each new non-employee director elected to our board of directors will be granted an initial, one-time award of a stock option to purchase 44,000 shares, which shall vest in equal quarterly installments over a three-year period from the date of vesting commencement, subject to continued service as a director through each such vesting date.

In addition, on the date of each annual meeting of stockholders of our company, each non-employee director will receive an annual stock option award of 22,000 shares, which shall vest in full upon the earlier to occur of the first anniversary of the date of grant or the date of the next annual meeting provided , however , that all vesting shall cease if the director resigns from the board of directors or otherwise ceases to serve as a director, unless the board of directors determines that the circumstances warrant continuation of vesting.

This program is intended to provide a total compensation package that enables us to attract and retain qualified and experienced individuals to serve as directors and to align our directors’ interests with those of our stockholders.

Security Ownership of Certain Beneficial Own ers and Management and Related Stockholder Matters.

Equity Compensation Plan Information

The following table provides information as of December 31, 2024 regarding shares of common stock that may be issued under our equity compensation plans, consisting of the 2018 Plan, the 2019 Plan and the 2019 Employee Stock Purchase Plan, or the ESPP.

We have no equity compensation plans that were not approved by security holders.

Plan Category

Number of securities

to be issued upon

exercise of outstanding

options, units and rights (#)

Weighted-average

exercise price of

outstanding options,

units and rights ($)

Number of securities

remaining available for

future issuance under

equity compensation plan

(excluding securities

referenced in first column)

Equity compensation plans approved by security holders(1)

11,231,148(2)

1,693,564(3)(4)

Equity compensation plans not approved by security holders

(1) Consists of our 2019 Stock Option and Incentive Plan, 2018 Stock Option and Grant Plan, and 2019 Employee Stock Purchase Plan.

Following our initial public offering, we have not and will not grant any awards under our 2018 Stock Option and Grant Plan, but all outstanding awards under the 2018 Stock Option and Grant Plan will continue to be governed by their existing terms.

The shares of common stock underlying any awards granted under the 2018 Stock Option and Grant Plan or 2019 Stock Option and Incentive Plan that are forfeited, canceled, reacquired by us prior to vesting, satisfied without the issuance of stock, or otherwise terminated (other than by exercise) and the shares of common stock that are withheld upon exercise of a stock option or settlement of such award to cover the exercise price or tax withholding will be added to the shares of common stock available for issuance under the 2019 Stock Option and Incentive Plan.

(2) Includes 11,231,148 shares of common stock issuable upon the exercise of outstanding options, of which 1,235,458 are subject to our 2018 Stock Option and Grant Plan and 9,995,690 are subject to our 2019 Stock Option and Incentive Plan.

(3) As of December 31, 2024, there were 1,379,305 shares available for grant under the 2019 Stock Option and Incentive Plan and 314,259 shares available for grants under the 2019 Employee Stock Purchase Plan.

(4) The 2019 Stock Option and Incentive Plan provides that the number of shares reserved and available for issuance under the plan will automatically increase each January 1, beginning on January 1, 2020, by 4% of the outstanding number of shares of our common stock on the immediately preceding December 31.

The 2019 Employee Stock Purchase Plan provides that the number of shares reserved and available for issuance will automatically increase each January 1, beginning on January 1, 2020, through January 1, 2029, by the least of 234,229 shares of our common stock, 1% of the outstanding number of shares of our common stock on the immediately preceding December 31, or such lesser number of shares as determined by our compensation committee.

Security Ownership of Certain Beneficial Owners and Management

The following table sets forth information, to the extent known by us or ascertainable from public filings, with respect to the beneficial ownership of our common stock as of March 7, 2025 by:

• each of our directors;

• each of our named executive officers;

• all of our directors and executive officers as a group;

• each person, or group of affiliated persons, who is known by us to beneficially own greater-than-5.0% of our common stock.

The column entitled “Shares Beneficially Owned” is based on a total of 50,743,101 shares of our common stock outstanding as of March 7, 2025.

Beneficial ownership is determined in accordance with the rules and regulations of the SEC and includes voting or investment power with respect to our common stock.

Shares of our common stock subject to options or warrants that are currently exercisable or exercisable within 60 days of March 7, 2025 are considered outstanding and beneficially owned by the person holding the options or warrants for the purpose of calculating the percentage ownership of that person but not for the purpose of calculating the percentage ownership of any other person.

Except as otherwise noted, the persons and entities in this table have sole voting and investing power with respect to all of the shares of our common stock beneficially owned by them, subject to community property

laws, where applicable.

Except as otherwise indicated in the table below, addresses of named beneficial owners are in care of Cabaletta Bio, Inc., 2929 Arch Street, Suite 600, Philadelphia, Pennsylvania 19104.

Shares beneficially owned

Name and address of beneficial owner(1)

> 5% Stockholders:

BlackRock, Inc.(2)

Entities Affiliated with Adage Capital Partners, L.P.(3)

Rowe Price Investment Management, Inc.(4)

Entities affiliated with Prudential Financial, Inc.(5)

Bain Capital Life Sciences Opportunities III, LP(6)

The Vanguard Group(7)

Named Executive Officers and Directors:

Steven Nichtberger, M.D.(8)

Binder, Ph.D.(9)

David Chang, M.D., M.P.H.(10)

Catherine Bollard, MBChB, M.D.(11)

Scott Brun, M.D.(12)

Richard Henriques, MBA(13)

Mark Simon, MBA(14)

Shawn Tomasello, MBA(15)

All executive officers and directors as a group (11 persons)(15)

* Represents beneficial ownership of less than one percent.

(1) Unless otherwise indicated, the address for each beneficial owner is c/o Cabaletta Bio, Inc., 2929 Arch Street, Suite 600, Philadelphia, Pennsylvania 19104.

(2) The information reported is based on information in a Schedule 13G/A, as filed by BlackRock, Inc.

with the SEC on February 5, 2025.

In that filing, BlackRock, Inc.

reports sole voting power with respect to 3,329,097 shares of common stock and sole dispositive power with respect to 3,397,260 shares, and lists its address as 50 Hudson Yards, New York, New York 10001.

(3) The information is based on a Schedule 13G/A filed with the SEC on November 12, 2024.

Consists of 3,036,645 shares of common stock and 597,830 shares of common stock issuable upon the exercise of pre-funded warrants held by Adage Capital Partners, L.P., or ACP.

Adage Capital Partners GP, L.L.C., or ACPGP, is the general partner of ACP.

Adage Capital Management, L.P., or ACM, is the investment manager of ACP.

Adage Capital Advisors, L.L.C., or ACA, is managing member of ACPGP.

Adage Capital Partners LLC, or ACPLLC , is the general partner of ACM, with respect to the shares of voting common stock directly held by ACP.

Robert Atchinson and Phillip Gross are managing members of ACA and ACPGP and are general partners of ACP.

Each of ACP, ACPGP, ACA, ACM, Robert Atchinson, and Phillip Gross have shared voting and dispositive power over all of the shares.

The ability of the Adage entities to exercise their pre-funded warrants is subject to a beneficial ownership limitation, which prevents the Adage entities from exercising any portion of the warrants to the extent such exercise would result in the Adage entities exceeding a certain percentage of the total number of issued and outstanding shares of our common stock following such exercise.

The address for Adage Capital Partners, L.P.

is 200 Clarendon Street, 52nd Floor, Boston, Massachusetts 02116.

(4) The information reported is based on information in a Schedule 13G/A, as filed by T.

Rowe Price Investment Management, Inc.

(Price Investment Management) with the SEC on November 14, 2024.

In that filing, T.

Rowe Price Investment Management, Inc.

(Price Investment Management) reports sole voting power with respect to 3,666,024 shares of common stock and sole dispositive power with respect to 3,673,724 shares, and lists its address as 101 E.

Pratt Street, Baltimore, MD 21201.

(5) The information reported is based on information in a Schedule 13G/A, as filed by Prudential Financial, Inc.

with the SEC on December 5, 2024.

In that filing, Prudential Financial, Inc.

reports shared voting and dispositive power over (i) 2,796,053 shares of our common stock, being 2,512,053 shares held through its subsidiary Jennison Associates LLC and 284,000 shares held through its subsidiary PGIM, Inc., and (ii) sole voting and dispositive power over 2,810 shares of our common stock held through its subsidiary PGIM Quantitative Solutions LLC.

The address provided for Prudential Financial, Inc.

is 751 Broad Street, New Jersey 07102.

(6) The information reported is based on information in a Schedule 13G, as filed by Bain Capital Life Sciences Opportunities III, LP with the SEC on August 22, 2024.

In that filing, Bain Capital Life Sciences Opportunities III, LP reports shared voting power and shared dispositive power with respect to 2,760,888 shares of common stock.

Bain Capital Life Sciences Investors, LLC, or BCLSI, is the manager of Bain Capital Life Sciences III General Partner, LLC, which is the general partner of Bain Capital Life Sciences Fund III, L.P., which is the sole member of Bain Capital Life Sciences Opportunities III GP, LLC, which is the general partner of Bain Capital Life Sciences Opportunities III, LP.

As a result, BCLSI may be deemed to share voting and dispositive power with respect to the securities held by Bain Capital Life Sciences Opportunities III, LP.

The address of BCLSI is 200 Clarendon Street, Boston, MA 02116.

(7) The information reported is based on information in a Schedule 13G/A, as filed by The Vanguard Group with the SEC on November 12, 2024.

In that filing, The Vanguard Group reports shared voting power with respect to 31,135 shares of common stock, sole dispositive power with respect to 2,500,994 shares and shared dispositive power with respect to 52,716 shares, and lists its address as 100 Vanguard Blvd., Malvern, PA 19355.

(8) Consists of (i) 986,483 shares of common stock held by Dr.

Nichtberger, (ii) 363,000 shares of common stock held by the 2017 Nichtberger Family Trust, or the Trust Shares, and (iii) 1,177,867 shares of common stock underlying options exercisable within 60 days of March 7, 2025.

Nichtberger may be deemed to beneficially own the Trust Shares.

Nichtberger disclaims beneficial ownership of the Trust Shares and this shall not be deemed an admission that he is the beneficial owner of the Trust Shares.

(9) Consists of (i) 20,000 shares of common stock held and (ii) 583,831shares of common stock underlying options exercisable within 60 days of March 7, 2025.

(10) Consists of 612,846 shares of common stock underlying options exercisable within 60 days of March 7, 2025.

(11) Consists of (i) 1,000 shares of common stock held and (ii) 112,428 shares of common stock underlying options exercisable within 60 days of March 7, 2025.

(12) Consists of 88,000 shares of common stock underlying options exercisable within 60 days of March 7, 2025.

(13) Consists of 112,428 shares of common stock underlying options exercisable within 60 days of March 7, 2025.

(14) Consists of (i) 143,144 shares of common stock held and (ii) 112,428 shares of common stock underlying options exercisable within 60 days of March 7, 2025.

(15) Consists of 25,667 shares of common stock underlying options exercisable within 60 days of March 7, 2025.

(16) See notes (7) through (14);

also includes an aggregate of (i) 50,000 shares of common stock and (ii) 1,066,947 shares of common stock subject to options exercisable within 60 days of March 7, 2025 held by Anup Marda, our Chief Financial Officer, Michael Gerard, our General Counsel and Secretary, and Arun Das, M.D., our Chief Business Officer.

Directors, Executive Officers and Corporate Governance.

Except as set forth below, the information required by this item is incorporated by reference from our definitive Proxy Statement to be filed with the SEC in connection with our 2026 Annual Meeting of Stockholders within 120 days after the end of the fiscal year ended December 31, 2025.

We have adopted a Code of Business Conduct and Ethics that applies to all of our directors, officers and employees, including our principal executive officer and principal financial officer.

The Code of Business Conduct and Ethics is posted on our website at http://investors.cabalettabio.com/corporate-governance/governance-highlights .

We intend to satisfy the disclosure requirement under Item 5.05 of Form 8-K regarding an amendment to, or waiver from, a provision of this Code of Business Conduct and Ethics by posting such information on our website, at the address and location specified above and, to the extent required by the listing standards of The Nasdaq Global Select Market, by filing a Current Report on Form 8-K with the SEC, disclosing such information.

Executive Compensation.

The information required by this Item 11 will be included in our definitive proxy statement to be filed with the SEC with respect to our 2026 Annual Meeting of Stockholders within 120 days after the end of the fiscal year ended December 31, 2025 and is incorporated herein by reference.

Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters.

The information required by this Item 12 will be included in our definitive proxy statement to be filed with the SEC with respect to our 2026 Annual Meeting of Stockholders within 120 days after the end of the fiscal year ended December 31, 2025 and is incorporated herein by reference.

Certain Relationships and Related Transactions, and Director Independence.

Certain Relationships and Transactions

Other than the compensation agreements and other arrangements described under “Executive compensation” and “Director compensation” in this Annual Report on Form 10-K for the fiscal year ended December 31, 2024 and the transactions described below, since January 1, 2023, there has not been and there is not currently proposed, any transaction or series of similar transactions to which we were, or will be, a party in which the amount involved exceeded, or will exceed, $120,000 (or, if less, 1% of the average of our total assets amounts at December 31, 2023 and 2024) and in which any director, executive officer, holder of five percent or more of any class of our capital stock or any member of the immediate family of, or entities affiliated with, any of the foregoing persons, had, or will have, a direct or indirect material interest.

May 2023 Offering

In May 2023, we issued 8,337,500 shares of our common stock at a price of $12.00 per share in connection with an underwritten public offering.

Certain existing holders of five percent or more of a class of our capital stock participated in the transaction, as evidenced by the table below.

Greater than Five Percent Holder

Aggregate Common Stock Purchased

Purchase Price

Adage Capital Partners LP

Fred Alger Management Inc

Cormorant Global Healthcare Master Fund LP

Commodore Capital LP

Limitation of Liability and Indemnification of Officers and Directors

Our certificate of incorporation contains provisions that limit the liability of our directors for monetary damages to the fullest extent permitted by Delaware law.

Consequently, our directors will not be personally liable to us or our stockholders for monetary damages for any breach of fiduciary duties as directors, except liability for the following:

• any breach of their duty of loyalty to our company or our stockholders;

• any act or omission not in good faith or that involves intentional misconduct or a knowing violation of law;

• unlawful payments of dividends or unlawful stock repurchases or redemptions as provided in Section 174 of the Delaware General Corporation Law;

• any transaction from which they derived an improper personal benefit.

Any amendment to, or repeal of, these provisions will not eliminate or reduce the effect of these provisions in respect of any act, omission or claim that occurred or arose prior to that amendment or repeal.

If the Delaware General Corporation Law is amended to provide for further limitations on the personal liability of directors of corporations, then the personal liability of our directors will be further limited to the greatest extent permitted by the Delaware General Corporation Law.

In addition, we adopted bylaws which provide that we will indemnify, to the fullest extent permitted by law, any person who is or was a party or is threatened to be made a party to any action, suit or proceeding by reason of the fact that he or she is or was one of our directors or officers or is or was serving at our request as a director or officer of another corporation, partnership, joint venture, trust, or other enterprise.

Our bylaws provide that we may indemnify to the fullest extent permitted by law any person who is or was a party or is threatened to be made a party to any action, suit, or proceeding by reason of the fact that he or she is or was one of our employees or agents or is or was serving at our request as an employee or agent of another corporation, partnership, joint venture, trust or other enterprise.

Our bylaws also provide that we must advance expenses incurred by or on behalf of a director or officer in advance of the final disposition of any action or proceeding, subject to very limited exceptions.

We have entered into and in the future plan to enter 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 to the maximum extent allowed under Delaware law.

Related person transaction policy

Our board of directors adopted a written related person transaction policy providing that transactions with our directors, officers and holders of five percent or more of our voting securities and their affiliates, each a related person, must be approved by our audit committee.

This policy became effective on October 29, 2019, the date our registration statement for our initial public offering became effective.

Pursuant to this policy, the audit committee has the primary responsibility for reviewing and approving or disapproving “related person 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.

For purposes of this policy, a related person is defined as a director, executive officer, nominee for director, or greater than 5% beneficial owner of our common stock, in each case since the beginning of the most recently completed year, and their immediate family members.

As appropriate for the circumstances, the audit committee will review and consider:

• the related person’s interest in the related person transaction;

• the approximate dollar amount involved in the related person transaction;

• the approximate dollar amount of the related person’s interest in the transaction without regard to the amount of any profit or loss;

• whether the transaction was undertaken in the ordinary course of our business;

• whether the terms of the transaction are no less favorable to us than terms that could have been reached with an unrelated third party;

• the purpose of, and the potential benefits to us of, the related-party transaction;

• any other information regarding the related-party transaction or the related person in the context of the proposed transaction that would be material to investors in light of the circumstances of the particular transaction.

Director Independence

Applicable Nasdaq rules require a majority of a listed company’s board of directors to be comprised of independent directors within one year of listing.

In addition, the Nasdaq rules require that, subject to specified exceptions, each member of a listed company’s audit, compensation and nominating and corporate governance committees be independent and that audit committee members also satisfy independence criteria set forth in Rule 10A-3 under the Exchange Act and that compensation committee members satisfy independence criteria set forth in Rule 10C-1 under the Exchange Act.

Under applicable Nasdaq rules, a director will only qualify as an “independent director” if, in the opinion of the listed 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, 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, accept, directly or indirectly, any consulting, advisory, or other compensatory fee from the listed company or any of its subsidiaries or otherwise be an affiliated person of the listed company or any of its subsidiaries.

In addition, in affirmatively determining the independence of any director who will serve on a company’s compensation committee, Rule 10C-1 under the Exchange Act requires that a company’s board of directors must consider 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:

the source of compensation to the director, including any consulting, advisory or other compensatory fee paid by such company to the director, and whether the director is affiliated with the company or any of its subsidiaries or affiliates.

Our board of directors has determined that all members of the board of directors, except Dr.

Nichtberger are independent directors, including for purposes of the rules of Nasdaq and the SEC.

In making such independence determination, our board of directors considered the relationships that each non-employee director has with us and all other facts and circumstances that our board of directors deemed relevant in determining their independence, including the beneficial ownership of our capital stock by each non-employee director.

In considering the independence of the directors listed above, our board of directors considered the association of our directors with the holders of more than 5% of our common stock.

There are no family relationships among any of our directors or executive officers.

Nichtberger is not an independent director under these rules because he is an executive officer of the Company.

Principal Accountant Fees and Services.

The information required by this Item 13 will be included in our definitive proxy statement to be filed with the SEC with respect to our 2026 Annual Meeting of Stockholders within 120 days after the end of the fiscal year ended December 31, 2025 and is incorporated herein by reference.

Principal Accounting Fees and Services.

The information required by this Item 14 will be included in our definitive proxy statement to be filed with the SEC with respect to our 2026 Annual Meeting of Stockholders within 120 days after the end of the fiscal year ended December 31, 2025 and is incorporated herein by reference.

Our independent public accounting firm is Ernst & Young, Philadelphia, PA, PCAOB Auditor ID 42 .

Cabaletta incurred the following fees from Ernst & Young for the audit of the financial statements and for other services provided during the years ended December 31, 2024 and 2023.

Audit fees(1)

Audit-Related fees(2)

All other fees(4)

(1) Audit fees consist of fees for the audit of our annual financial statements, the review of our interim financial statements included in our quarterly reports on Form 10-Q, comfort letters and consents.

(2) Audit-related fees consist of services that are reasonably related to the performance of the audit or review of our financial statements.

There were no such fees incurred in 2024 or 2023.

(3) Tax Fees consist of fees for tax compliance, advice and tax services.

(4) There were no other fees incurred in 2024 or 2023.

Audit Committee Pre-approval Policy and Procedures

Our audit committee has adopted policies and procedures relating to the approval of all audit and non-audit services that are to be performed by our independent registered public accounting firm.

This policy provides that we will not engage our independent registered public accounting firm to render audit or non-audit services unless the service is specifically approved in advance by our audit committee or the engagement is entered into pursuant to the pre-approval procedure described below.

From time to time, our audit committee may pre-approve specified types of services that are expected to be provided to us by our independent registered public accounting firm during the next 12 months.

Any such pre-approval details the particular service or type of services to be provided and is also generally subject to a maximum dollar amount.

During our 2024 and 2023 fiscal years, no services were provided to us by Ernst & Young other than in accordance with the pre-approval policies and procedures described above.

Exhibits, Consolidated Financ ial Statement Schedules.

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Notes to Consolidated Financial Statements

Report of Independent Regist ered Public Accounting Firm

Report of Independent Registered Public Accounting Firm

To the Stockholders and the Board of Directors of Cabaletta Bio, Inc.

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We believe that our audits provide a reasonable basis for our opinion.

Critical Audit Matter

The critical audit matter communicated below is a matter arising from the current period audit of the financial statements that was communicated or required to be communicated to the audit committee and that:

(1) relates to accounts or disclosures that are material to the financial statements and (2) involved our especially challenging, subjective or complex judgments.

The communication of the critical audit matter does not alter in any way our opinion on the consolidated financial statements, taken as a whole, and we are not, by communicating the critical audit matter below, providing a separate opinion on the critical audit matter or on the account or disclosures to which it relates.

Critical Audit Matters

The critical audit matters communicated below are matters arising from the current period audit of the financial statements that were communicated or required to be communicated to the audit committee and that:

(1) relate to accounts or disclosures that are material to the financial statements and (2) involved our especially challenging, subjective or complex judgments.

The communication of critical audit matters does not alter in any way our opinion on the consolidated financial statements, taken as a whole, and we are not, by communicating the critical audit matters below, providing separate opinions on the critical audit matters or on the accounts or disclosures to which they relate.

Accounting for Accrued Clinical Trial Expenses

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The Company’s accrued clinical trial expenses are based on factors such as estimates of the work completed in accordance with agreements established with a contract research organization.

As disclosed in Note 5 to the consolidated financial statements, the Company’s total accrued expenses and other current liabilities related to research and development costs were $3.5 million at December 31, 2024, which included the estimated clinical trial expenses incurred as of December 31, 2024 but not paid as of that date.

As disclosed in Note 5 to the consolidated financial statements, the Company’s total accrued expenses and other current liabilities related to clinical trial research and development services were $5.3 million at December 31, 2025.

Auditing the Company’s accrued clinical trial expenses required subjective auditor judgement due to the estimation required by management in determining the services provided but not yet invoiced.

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To evaluate the completeness of the accruals, we also examined subsequent invoices from the service providers and cash disbursements to the service providers, to the extent such invoices were received, or payments were made prior to the date that the consolidated financial statements were issued.

Accounting for Common Stock Warrants

Description of the Matter

As discussed in Note 10 to the consolidated financial statements, in June 2025, concurrent with the issuance of common stock and pre-funded warrants, the Company issued a total of 53,090,190 common stock warrants.

The common stock warrants were classified as a component of permanent stockholders’ equity within additional paid-in capital.

Auditing management’s evaluation of whether the common stock warrants required classification as a liability or equity is especially challenging and required significant audit effort and judgment due to the complex assessment of provisions within the warrants under authoritative guidance.

How We Addressed the Matter in Our Audit

To test the classification of the common stock warrants, our audit procedures included, among others, reviewing terms and conditions of the common stock warrant agreements, evaluating management's application of authoritative accounting guidance and related judgments, and testing the accuracy of underlying data supporting management’s assertions.

We involved our

internal accounting subject matter resources to assist in evaluating the Company’s assessment and judgments applied in its evaluation of the classification for the warrants.

/s/ Ernst & Young LLP

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(in thousands, except share and per share amounts)

Year Ended December 31,

Current assets:

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Voting and non-voting common stock, $ 0.00001 par value:

( 143,590,481 voting and 6,409,519 non-voting) shares authorized as of

December 31, 2024 and December 31, 2023;

50,743,101 voting shares

issued and outstanding as of December 31, 2024 and 47,823,232

( 46,378,937 voting and 1,444,295 non-voting) shares issued and

outstanding as of December 31, 2023

( 293,590,481 voting and 6,409,519 non-voting) shares

authorized as of December 31, 2025 and 150,000,000

( 143,590,481 voting and 6,409,519 non-voting) shares authorized

as of December 31, 2024;

100,479,323 voting shares issued

and outstanding as of December 31, 2025 and 50,743,101

voting shares issued and outstanding as of December 31, 2024

Additional paid-in capital

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(in thousands, except share and per share amounts)

Year Ended December 31,

Operating expenses:

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Loss from operations

Other income:

Other income (expense):

Interest income

Interest expense

Other income, net

Other comprehensive income:

Net unrealized (loss) gain on available-for-sale investments, net of tax

Net unrealized gain (loss) on available-for-sale investments, net of tax

Net comprehensive loss

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Consolidated Statements of Stockholders’ Equity

(in thousands, except share and per share amounts)

(in thousands, except share amounts)

Paid-in Capital

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Balance—December 31, 2023

Stock-based compensation

Issuance of common stock, net of issuance costs of $ 252

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Issuance of common stock upon exercise of pre-funded warrants

Stock-based compensation

Net unrealized losses on available-for-sale securities

Balance—December 31, 2024

Stock-based compensation

Issuance of common stock, net of issuance costs of $ 252

Issuance of common stock in connection with exercise of stock options

Issuance of common stock under employee stock purchase plan

Issuance of common stock, warrants and pre-funded warrants, net of issuance costs of $ 6,442

Issuance of common stock from ATM offering, net of sales agent commission and fees

Issuance of common stock upon exercise of pre-funded warrants

Net unrealized losses on available-for-sale securities

Issuance of common stock under employee stock purchase plan

Issuance of common stock in connection with exercise of stock options

Stock-based compensation

Net unrealized gains on available-for-sale securities

Balance—December 31, 2025

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Stock-based compensation

Amortization of finance lease

Non-cash finance lease expense

Non-cash operating lease expense

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Lease liabilities

Accrued interest payable under finance lease

Net cash used in operating activities

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Proceeds from maturities of investments

Net cash provided by (used in) investing activities

Net cash (used in) provided by investing activities

Cash flows from financing activities:

Proceeds from the issuance of common stock, net of issuance costs

Proceeds from the issuance of common stock, warrants and pre-funded warrants, net of issuance costs

Issuance of common stock from ATM offering, net of sales agent commission and fees

Proceeds from issuance of common stock under employee stock purchase plan

Proceeds from issuance of common stock in connection with the

exercise of stock options

Proceeds from issuance of common stock under employee stock

purchase plan

Principal payments on finance leases

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Effect of exchange rate changes on cash and cash equivalents

Net (decrease) increase in cash and cash equivalents

Net decrease in cash and cash equivalents

Cash and cash equivalents—beginning of period

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and, in August 2018, changed its name to Cabaletta Bio, Inc.

The consolidated financial statements include the accounts of Cabaletta Bio and its wholly owned subsidiaries:

The consolidated financial statements include the accounts of Cabaletta and its wholly owned subsidiaries:

Cabaletta Bio GmbH and Cabaletta Bio (Germany) GmbH.

All intercompany balances and transactions have been eliminated in consolidation.

The Company is headquartered in Philadelphia, Pennsylvania.

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The Company has sustained annual operating losses since inception and expects to continue to generate operating losses for the foreseeable future.

As of December 31, 2024, the Company has incurred an accumulated deficit of $ 349,101 and has a cash and cash equivalents balance of $ 163,962 .

As of December 31, 2025, the Company has incurred an accumulated deficit of $ 516,957 and has cash, cash equivalents and investments of $ 133,599 .

The Company’s ultimate success depends on the outcome of its research and development activities.

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However, if such financing is not available at adequate levels and on a timely basis, or such agreements are not available on favorable terms, or at all, as and when needed, the Company will need to reevaluate its operating plan and may be required to delay or discontinue the development of one or more of its product candidates or operational initiatives.

The Company expects that its current cash and cash equivalents may not be sufficient to fund operations for at least the next twelve months from the date of issuance of these consolidated financial statements.

Based on the Company’s current operating plan, there is substantial doubt about the Company’s ability to continue as a going concern for at least twelve months from the issuance date of this Annual Report on Form 10-K, and the Company will need to obtain additional funding.

The Company's cash forecast contains estimates and assumptions based on success of ongoing clinical trials, and management cannot predict the amount or timing of all expenditures with certainty.

Accordingly, the Company has concluded that substantial doubt exists about the Company’s ability to continue as a going concern.

The accompanying financial statements have been prepared on a going concern basis, which contemplates the realization of assets and satisfaction of liabilities in the ordinary course of business.

The accompanying financial statements have been

prepared on a going concern basis, which contemplates the realization of assets and satisfaction of liabilities in the ordinary course of business.

Summary of Significant Accounting Policies

Principles of Consolidation

The accompanying consolidated financial statements included herein have been prepared in conformity with accounting principles generally accepted in the United States ("GAAP") and under the rules and regulations of the U.S.

The accompanying consolidated financial statements have been prepared in conformity with generally accepted accounting principles in the United States (GAAP) and under the rules and regulations of the U.S.

Securities and Exchange Commission (SEC).

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Use of Estimates

The preparation of consolidated financial statements in conformity with accounting principles generally accepted in the United States of America (GAAP) requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities as of the date of the consolidated financial statements and the reported amounts of expenses during the reporting period.

The preparation of consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities as of the date of the consolidated financial statements and the reported amounts of expenses during the reporting period.

Significant estimates and assumptions made in the accompanying consolidated financial statements include but are not limited to advance payments and accruals related to the Company’s research and development expenses .

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Financial instruments, which potentially subject the Company to significant concentrations of credit risk, consist of cash and cash equivalents, which are invested in U.S.

treasury-based money market funds.

As of December 31, 2023, the Company held available-for-sale securities, which were invested in U.S.

treasury-based money market funds, and available-for-sale debt securities, which are invested in U.S.

treasury securities.

These investments matured in 2024.

A portion of the Company’s cash is maintained at two federally insured financial institutions, and account balances may at times exceed federally insured limits.

A portion of the Company’s cash is maintained at federally insured financial institutions, and account balances may at times exceed federally insured limits.

The Company has not experienced any losses in such accounts and management believes that the Company is not exposed to significant credit risk.

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The Company considers all highly liquid investments purchased with original maturities of three months or less from the purchase date to be cash equivalents.

Cash equivalents consist primarily of amounts invested in money market accounts.

Cash equivalents consist primarily of amounts invested in money market accounts and U.S.

treasury securities.

Investments are available-for-sale and carried at estimated fair value.

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Valuation allowances are established when necessary to reduce deferred tax assets where, based upon the available evidence, the Company concludes that it is more-likely-than-not that the deferred tax assets will not be realized.

In evaluating its ability to recover deferred tax assets, the Company considers all available positive and negative evidence, including its operating results, ongoing tax planning and forecasts of future taxable income on a jurisdiction-by-jurisdiction basis.

jurisdiction-by-jurisdiction basis.

Because of the uncertainty of the realization of deferred tax assets, the Company has recorded a full valuation allowance against its deferred tax assets.

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Net Loss Per Share

The Company calculates basic and diluted net loss per share in conformity with the two-class method required for participating securities because the Company had both voting and non-voting common stock outstanding in 2023 and for a portion of 2024.

The rights, including the liquidation and dividend rights, of the holders of the voting and non-voting common stock are identical, except with respect to voting.

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Should an in-process equity financing be abandoned, the deferred offering costs will be expensed immediately as a charge to operating expenses in the statements of operations and comprehensive loss.

Emerging Growth Company Status

Prior to December 31, 2024, the Company was an “emerging growth company” (EGC) as defined in the Jumpstart Our Business Startups Act, (JOBS Act), and elected to take advantage of certain exemptions from various reporting requirements that are applicable to other public companies until the Company no longer qualifies as an EGC, including using the extended transition period for complying with new or revised accounting standards.

As of December 31, 2024, the Company ceased to qualify as an EGC.

Recently Adopted Accounting Pronouncements

In November 2023, the FASB issued Accounting Standards Update, or ASU, 2023-07, Segment Reporting (Topic 280) – Improvements to Reportable Segment Disclosures .

This ASU requires that a public entity provide additional segment disclosures on an interim and annual basis.

The amendments in this ASU should be applied retrospectively to all prior periods presented in the consolidated financial statements, unless impracticable.

Upon transition, the segment expense categories and amounts disclosed in the prior periods should be based on the significant segment expense categories identified and disclosed in the period of adoption.

The Company adopted this ASU for the annual period ended December 31, 2024 and the amendments have been applied retrospectively to all prior periods presented in the financial statements.

Refer to Note 8 – Segment Reporting for further information related to our segment.

Recently Issued Accounting Pronouncements

In December 2023, the FASB issued ASU 2023-09, Improvements to Income Tax Disclosures .

ASU 2023-09 enhances the transparency about income tax information through improvements to income tax disclosures primarily related to the rate reconciliation and income taxes paid information.

The guidance is effective for public business entities for annual periods beginning after December 15, 2024.

Early adoption is permitted.

This update is effective beginning with the Company’s 2025 fiscal year annual reporting period.

The Company is currently planning to adopt this guidance when effective and is assessing the impact of the adoption on the Company’s consolidated financial statements and accompanying footnotes.

The Company adopted this ASU for the annual period ended December 31, 2025 and the amendments have been applied retrospectively to all prior periods presented in the financial statements.

Refer to Note 11 – Income Taxes for further information.

Recently Issued Accounting Pronouncements

In November 2024, the FASB issued ASU 2024-03, Income Statement (Subtopic 220-40):

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Money market funds

Treasury securities - original maturity less than three months

Short-term investments:

Treasury securities

Money market funds are measured at fair value on a recurring basis using quoted prices and are classified as Level 1.

Money market funds are measured at fair value on a recurring basis using quoted prices and are classified as Level 1 inputs.

Investments are measured at fair value based on inputs other than quoted prices that are derived from observable market data and are classified as Level 2 inputs.

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Gross Unrealized Gains

Gross Unrealized Losses

Financial assets

Money market funds

Treasury securities - original maturity less than three months

Included in cash and cash equivalents

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Accrued and other current liabilities consist of the following:

Research and development services

General and administrative services

Compensation expense

Clinical trial research and development services

Manufacturing and other research and development services

General and administrative services

Collaborations, Licensing Agreements and Other Agreements

Amended and Restated License Agreement with the Trustees of the University of Pennsylvania and Children’s Hospital of Philadelphia

In August 2018, the Company entered into a license agreement with Penn, as amended and restated in July 2019 to include the Children’s Hospital of Philadelphia (CHOP) as a party, and as amended in May 2020 and October 2021 (the License Agreement) pursuant to which the Company obtained (a) a non-exclusive, non-sublicensable worldwide license to certain of Penn’s intellectual property to conduct research, product development, clinical trials, cell manufacturing and other activities, and (b) an exclusive, worldwide, royalty-bearing right and license, with a right to sublicense, on a target-by-target basis, under certain of Penn’s intellectual property to make, use, sell, offer for sale, import, and otherwise commercialize products for the treatment of autoimmune and alloimmune diseases.

In August 2018, the Company entered into a license agreement with the University of Pennsylvania (Penn), as amended and restated in July 2019 to include the Children’s Hospital of Philadelphia (CHOP) as a party, and as amended in May 2020 and October 2021 (the License Agreement) pursuant to which the Company obtained (a) a non-exclusive, non-sublicensable worldwide license to certain of Penn’s intellectual property to conduct research, product development, clinical trials, cell manufacturing and other activities, and (b) an exclusive, worldwide, royalty-bearing right and license, with a right to sublicense, on a target-by-target basis, under certain of Penn’s intellectual property to make, use, sell, offer for sale, import, and otherwise commercialize products for the treatment of autoimmune and alloimmune diseases.

Unless earlier terminated, the License Agreement expires on the expiration or abandonment or other termination of the last valid claim in Penn’s intellectual property licensed by the Company.

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There were no amounts due under the License Agreement as of December 31, 2025.

Master Translational Research Services Agreement

Master Translational Research Services Agreements

In October 2018 and February 2023, the Company entered into services agreements (the CAART and CARTA Services Agreements) with Penn for research, development and manufacturing services from various laboratories within Penn.

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In May 2020, the Company amended its Addendum with the Center for Advanced Retinal and Ocular Therapeutics (CAROT) to expand access to vector manufacturing.

Research and development expense related to executed addenda under the master translational research service agreements with Penn recognized in the accompanying statements of operations was $ 3,250 and $ 3,786 for the years ended December 31, 2024 and 2023, respectively.

The Company is committed to pay up to $ 3,000 under the CARTA Services Agreement for cell processing manufacturing through December 31, 2025.

The Company may incur additional expenses up to $ 643 t hrough the remaining term of the CAROT Amended Addendum.

Research and development expense recognized under executed addenda to the master translational research services agreements with Penn was $ 5,062 and $ 3,250 for the years ended December 31, 2025 and 2024, respectively.

As of December 31, 2025 , the Company had no remaining commitments under the CARTA Services Agreement.

Exclusive License Agreement with IASO Biotherapeutics

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In December 2021, the Company entered into a Licence and Supply agreement (LSA) with Oxford Biomedica (UK) Limited (Oxford), wherein the LSA grants the Company a non-exclusive license to Oxford’s LentiVector® platform for its application in the Company’s DSG3-CAART program and put in place a multi-year vector supply agreement.

Under the terms of the agreement, the Company was required to pay Oxford an upfront fee, as well as costs associated with initial vector manufacturing activities for a total cost incurred of $ 1,100 .

Oxford is eligible to receive regulatory and sales milestones in the low tens of millions and royalties in the low single digits on net sales of products that incorporate the Oxford technology.

In May 2023, the Company amended the LSA with Oxford to expand the license to include the Company's rese-cel program for an upfront fee of $ 500 , and in August 2023, the Company and Oxford entered into a vector supply agreement for rese-cel, and a related second amendment to the LSA, with a total cost under the vector supply agreement of up to approximately $ 5,000 , of which approximately $ 3,500 and $ 1,500 were recognized as research and development expense for the years ended December 31, 2024 and 2023, respectively.

In May 2023, the Company amended the LSA with Oxford to expand the license to include the Company's rese-cel program for an upfront fee of $ 500 .

In August 2023, the Company and Oxford entered into a vector supply agreement for rese-cel, and a related second amendment to the LSA, with a total cost under the vector supply agreement of up to approximately $ 5,000 , which has been fully expensed as of December 31, 2024.

In February 2024, the Company and Oxford entered into a third amendment to the LSA to update the patent schedule.

In June 2024, the Company and Oxford entered into a fourth amendment to the LSA elimin ating royalties on net sales of products that incorporate the Oxford technology if Oxford manufactures the vector.

In December 2024, the Company and Oxford entered into a work order with a cost of approximately $ 9,000 for certain process characterization activities as part of commercial readiness activities.

In June 2024, the Company and Oxford entered into a fourth amendment to the LSA eliminating royalties on net sales of products that incorporate the Oxford technology if Oxford manufactures the vector.

Starting in December 2024, the Company and Oxford entered into work orders with a cost of approximately $ 23,000 for certain process characterization and process performance qualification activities as part of commercial readiness activities.

As of December 31, 2025 , the Company has recognized project to date expense of $ 8,673 related to these activities.

The Company can terminate the LSA or any work order under the LSA at will upon advance written notice and subject to certain cancellation fees.

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Manufacturing Agreements

In January 2021, the Company entered into a Development and Manufacturing Services Agreement (WuXi Agreement) with WuXi Advanced Therapies, Inc.

(WuXi) to serve as an additional cell processing manufacturing partner for the MuSK-CAART Phase 1 clinical trial, or MusCAARTes TM trial.

The WuXi Agreement is scheduled to expire upon completion of WuXi's services related to MuSK-CAART and rese-cel.

In August 2023, and as extended in August 2024, the Company entered into an agreement with WuXi to serve as one of the Company's manufacturing partners for the global clinical development of rese-cel in multiple indications, including potential late-stage clinical trials and commercial readiness activities for rese-cel.

Under the August 2023 work orders, WuXi converted the Company’s non-dedicated suite to a dedicated suite for GMP manufacturing for the Company’s rese-cel and MuSK-CAART programs, or the Dedicated Suite, for an initial term of 18 months with two 18-month extensions at the Company’s sole option on six months' notice prior to the end of the term.

In August 2024, the Company sent a notice to WuXi to extend the initial term of the WuXi Agreement by 18 months through August 2026.

In January 2021, the Company entered into a Development and Manufacturing Services Agreement (Minaris Agreement) with Minaris Advanced Therapies, LLC, or Minaris (f/k/a WuXi Advanced Therapies, Inc.) to serve as an additional cell processing manufacturing partner for the MuSK-CAART Phase 1 clinical trial, or MusCAARTes TM trial.

The Minaris Agreement is scheduled to expire upon completion of Minaris' services related to MuSK-CAART and rese-cel.

In August 2023, and as extended in August 2024, the Company entered into an agreement with Minaris to serve as one of the Company's manufacturing partners for the global clinical development of rese-cel in multiple indications, including potential late-stage clinical trials and commercial readiness activities for rese-cel.

Under the August 2023 work orders, Minaris converted the Company’s non-dedicated suite to a dedicated suite for GMP manufacturing for the Company’s rese-cel and MuSK-CAART programs, or the Dedicated Suite, for an initial term of 18 months with two 18-month extensions at the Company’s sole option on six months' notice prior to the end of the term.

In August 2024, the Company sent a notice to Minaris to extend the initial term of the Minaris Agreement by 18 months through August 2026.

In addition, the Company agreed to certain monthly minimum runs.

In August 2024, the 2023 work order related to GMP manufacturing was amended to reduce the minimum monthly runs through the end of 2024.

In lieu of the original $ 1,500 termination fee under the terms of the WuXi Agreement, the Company would incur up to a $ 1,080 termination fee if it terminates both the rese-cel and MuSK-CAART work orders for any reason.

The Company may terminate for

convenience the WuXi Agreement or any work order with six months' prior written notice.

However, the Company may not terminate the Dedicated Suite without terminating both the MuSK-CAART and rese-cel GMP run work orders.

WuXi may terminate for convenience the WuXi Agreement or any work order on 18 months' prior written notice, but such notice may not be effective prior to February 2028.

In lieu of the original $ 1,500 termination fee under the terms of the Minaris Agreement, the Company would incur up to a $ 1,080 termination fee if it terminates both the rese-cel and MuSK-CAART work orders for any reason.

The Company may terminate for convenience the Minaris Agreement or any work order with six months' prior written notice.

However, the Company may not terminate the Dedicated Suite without terminating

both the MuSK-CAART and rese-cel GMP run work orders.

Minaris may terminate for convenience the Minaris Agreement or any work order on 18 months' prior written notice, but such notice may not be effective prior to February 202 8.

In February 2026, the Company notified Minaris that it intended to permit the term to expire in August 2026.

In December 2024, the Company entered into a Development and Manufacturing Services Agreement (the Lonza Agreement) with Lonza Houston Inc.

(Lonza) to serve as one of the Company's manufacturing partners for the global clinical development of rese-cel in multiple indications, including potential late-stage clinical trials and preparations for commercial readiness.

Under the initial work order, Lonza will perform cell therapy manufacturing activities for Cabaletta’s CAR-T cell therapy product rese-cel for a term of 12 months and total cost of approximately $ 16,000 with the ability to extend the manufacturing period subject to the terms of the Lonza Agreement.

The Lonza Agreement has a term of five years and can be extended for an additional three year term upon notice to Lonza at least 18 months prior to the expiration of the Lonza Agreement.

The Company can terminate the Lonza Agreement at will upon nine months advance written notice to Lonza subject to the terms of the Lonza Agreement.

Lonza can terminate the Lonza Agreement at will upon 24 months advance written notice to Cabaletta subject to the terms of the Lonza Agreement.

Under the initial work order, Lonza will perform cell therapy manufacturing activities for Cabaletta’s CAR-T cell therapy product, rese-cel, for an initial term of 12 months with the ability to extend the manufacturing period on a rolling basis subject to the terms of the Lonza Agreement.

Other Purchase Commitments

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The Company’s CODM is the CEO.

The Company has determined that it has one operating and reportable segment.

The Company has determined it operates in a single operating segment and has one reportable segment.

The segment consists of the development of clinical and preclinical product candidates for the discovery and development of innovative engineered T cell therapies and related administrative activities.

CODM assesses performance and allocates resources based on the Company’s consolidated statement of operations, which is reported on the income statement as consolidated net loss and considers forecast-to-actuals variances on a quarterly basis for expenses that are deemed significant.

The CODM assesses performance and allocates resources based on the Company’s consolidated statement of operations, which is reported on the income statement as consolidated net loss and considers forecast-to-actuals variances on a quarterly basis for expenses that are deemed significant.

Further, the CODM reviews the segment’s assets based on the consolidated balance sheet to assess liquidity and funding capacity.

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Clinical trials

Development services

Manufacturing of preclinical and clinical supplies

Development services

License of intellectual property

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Interest expense

Other income, net

(1) Other research and development costs includes costs associated with information technology, travel, medical and scientific symposiums and conferences.

The Company leases office and laboratory space in addition to a manufacturing agreement which has been determined to contain an embedded lease.

The Company leases office and laboratory space and has two manufacturing agreements that have been determined to include embedded leases.

Operating lease commitments

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The Company has elected the practical expedient to account for lease and non-lease components as a single-lease component and has included fixed payments related to non-lease components in calculating the operating lease liability.

In 2024, the Company extended the terms of its lab and office operating leases and leased additional lab space resulting in an increase in the right-of-use asset and lease liability of $ 4,242 .

The lease term

for our laboratory space was extended in October 2025 through November 2026 resulting in an increase of the right-of-use asset and lease liability of $ 787 .

Finance lease commitments - Embedded leases

As described further in Note 7, in August 2023, the Company entered into new work orders under the WuXi Agreement for WuXi to serve as one of the Company’s cell processing manufacturing partners for the global clinical development of rese-cel.

WuXi converted the Company’s non-dedicated suite to a Dedicated Suite for GMP manufacturing for the Company’s rese-cel and MuSK-CAART programs, for an initial term of 18 months.

As described further in Note 7, in August 2023, the Company entered into new work orders under the Minaris Agreement for Minaris to serve as one of the Company’s cell processing manufacturing partners for the global clinical development of rese-cel.

Minaris converted the Company’s non-dedicated suite to a Dedicated Suite for GMP manufacturing for the Company’s rese-cel and MuSK-CAART programs, for an initial term of 18 months.

The terms of the August 2023 work orders included both fixed costs and contingent variable costs.

The lease commenced October 1, 2023.

In 2024, the Company remeasured the lease due to resolution of the contingency related to variable costs and an amendment to the 2023 work order to extend the term of the agreement for an additional 18 months through August

2026 resulting in an increase in the right-of-use asset and lease liability of $ 10,963 .

In 2024, the Company remeasured the lease following the resolution of the contingency related to variable costs and an amendment to the 2023 work order, which extended the term of the agreement by an additional 18 months through August 2026.

The Company may terminate the Dedicated Suite lease for convenience with six months’ prior written notice and up to a $ 1,080 termination fee if both the rese-cel and MuSK-CAART work orders are terminated .

As described further in Note 7, in December 2024, the Company entered into the Lonza Agreement with Lonza to serve as one of our manufacturing partners.

Under the initial work order, Lonza will perform cell therapy manufacturing activities for our CAR-T cell therapy product rese-cel for a term of 12 months and total cost of approximately $ 16,000 with the ability to extend the manufacturing period subject to the terms of the Lonza Agreement.

The Lonza Agreement is currently being evaluated for lease accounting under ASC 842.

No right-of-use asset or liability was recognized as of December 31, 2024, as lease commencement begins in fiscal year 2025.

Summary of lease costs recognized under ASC 842

The following table contains a summary of the lease costs recognized under ASC 842 and other information pertaining to the Company’s operating and finance leases for the years ended December 31, 2024 and 2023.

For the year ended December 31,

In February 2026, the Company notified Minaris that it intended to permit the term to expire in August 2026.

As described further in Note 7, in December 2024, the Company entered into the Lonza Agreement with Lonza to serve as one of the Company's cell processing manufacturing partners.

Under the initial work order, Lonza will perform cell therapy manufacturing activities for the CAR-T cell therapy product rese-cel for a term of 12 months with the ability to extend the manufacturing period subject to the terms of the Lonza Agreement.

The Lonza Agreement was evaluated under ASC 842 and determined to contain an embedded finance lease commencing in March 2025, resulting in the recognition of a right-of-use asset and lease liability of $ 14,934 .

As of December 31, 2025, the Company extended the lease term in accordance with the Lonza Agreement resulting in an increase of the right-of-use asset and lease liability of $ 6,137 .

Summary of leases under ASC 842

The following table contains information pertaining to the Company’s operating and finance leases for the years ended December 31, 2025 and 2024.

Year Ended December 31,

Finance leases

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For finance leases embedded in CDMO arrangements, interest expense is recognized using the effective interest method, applying the Company's incremental borrowing rate as required by ASC 842, and amortization expense is recognized on a straight-line basis over the shorter of the life of the asset or the term of the lease.

Future lease payments under the non-cancelable operating and finance leases as of December 31, 2024 are as follows :

Future lease payments under the non-cancelable leases as of December 31, 2025 are as follows :

Finance Leases

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Total lease liability

Pursuant to the Company’s Third Amended and Restated Certificate of Incorporation filed in October 2019, the Company is authorized to issue 143,590,481 shares of voting common stock and 6,409,519 shares of non-voting common stock.

Holders of voting common stock shall have the exclusive right to vote for the election of directors of the Company and on all other matters requiring stockholder action.

Each share of the Company’s non-voting common stock may be converted at any time into one share of common stock at the option of its holder by providing 61 days written notice to the Company , subject to certain limitations, as described in the amended and restated certificate of incorporation.

In May 2024, 1,444,295 shares of non-voting common stock was converted to voting common stock and no shares of non-voting common stock remain outstanding.

May 2023 Financing

In May 2023, the Company issued 8,337,500 shares of its common stock in an underwritten public offering, including the exercise in full by the underwriters of their option to purchase an additional 1,087,500 shares, at a public offering price of $ 12.00 per share.

Aggregate net proceeds were $ 93,755 after deducting underwriting discounts and commissions and offering expenses of $ 6,295 .

December 2022 Financing

In December 2022, the Company issued 126,815 shares of its common stock at a price of $ 5.52 per share and to certain investors in lieu of common stock, pre-funded warrants to purchase 6,213,776 shares of common stock at a price of $ 5.51999 per pre-funded warrant.

The purchase price per share of each pre-funded warrant represents the per share offering price for the common stock, minus the $ 0.00001 per share exercise price of such pre-funded warrant.

Aggregate net proceeds were $ 32,562 after deducting underwriting discounts and commissions and offering expens es.

As of December 31, 2024, 6,213,775 pre-funded warrants had been exercised and no warrants remain outstanding.

The pre-funded warrants were classified as a component of permanent stockholders’ equity within additional paid-in capital and were recorded at the issuance date using a relative fair value allocation method.

The pre-funded warrants are equity classified because they (i) are freestanding financial instruments that are legally detachable and separately exercisable from the equity instruments, (ii) are immediately exercisable, (iii) do not embody an obligation for the Company to repurchase its shares, (iv) permit the holders to receive a fixed number of shares of common stock upon exercise, (v) are indexed to the Company’s common stock and (vi) meet the equity classification criteria.

In addition, such pre-funded warrants do not provide any guarantee of value or return.

Pursuant to the Company’s Third Amended and Restated Certificate of Incorporation, as amended, the Company is authorized to issue 293,590,481 shares of voting common stock and 6,409,519 shares of non-voting common stock.

In May 2024, the remaining 1,444,295 shares of non-voting common stock were converted to voting common stock and no shares of non-voting common stock are outstanding as of December 31, 2025.

June 2025 Financing

In June 2025, the Company issued (i) 39,200,000 shares of its common stock and accompanying warrants to purchase an aggregate of 39,200,000 shares of common stock (or pre-funded warrants in lieu thereof) and (ii) in lieu of common stock, to certain investors, pre-funded warrants to purchase an aggregate of up to 10,800,000 shares of its common stock and accompanying warrants to purchase an aggregate of 10,800,000 shares of common stock (or pre-funded warrants in lieu thereof), at an exercise price of $ 0.00001 per pre-funded warrant.

An additional 3,090,190 common stock warrants were issued in the financing for shares purchased by the underwriters in the market to cover overallotment demand.

The combined offering price of each share of common stock and accompanying common stock warrant was $ 2.00 .

The combined offering price of each pre-funded warrant and accompanying common stock warrant was $ 1.99999 .

The pre-funded warrants are exercisable immediately.

The common stock and pre-funded warrants were sold in combination with an accompanying common stock warrant to purchase one share of common stock (or a pre-funded warrant in lieu thereof) for each share of common stock or pre-funded warrant sold.

Each common stock warrant has an exercise price per share of $ 2.50 .

The common stock warrants are immediately exercisable from the date of issuance and will expire on September 12, 2026, fifteen months from the date of issuance.

Aggregate net proceeds were $ 93,558 after deducting underwriting discounts and commissions and offering expenses.

As of December 31, 2025 , 4,800,000 pre-funded warrants had been exercised and 6,000,000 remain outstanding.

As of December 31, 2025 , no common stock warrants had been exercised and 53,090,190 remain outstanding.

Subsequent to December 31, 2025 , 2,775,100 common stock warrants were exercised for proceeds of $ 6,938 .

The pre-funded warrants and common stock warrants were classified as a component of permanent stockholders’ equity within additional paid-in capital and were recorded at the issuance date using a relative fair value allocation method.

The pre-funded warrants and common stock warrants are equity classified because they (i) are freestanding financial instruments that are legally detachable and separately exercisable from the equity instruments, (ii) are immediately exercisable, (iii) do not embody an obligation for the Company to repurchase its shares, (iv) permit the holders to receive a fixed number of shares of common stock upon exercise, (v) are indexed to the Company’s common stock and (vi) meet the equity classification criteria.

In addition, such pre-funded warrants and common stock warrants do not provide any guarantee of value or return.

At-the-Market Offering

On March 21, 2024, the Company filed an automatic shelf registration statement (S-3ASR) in relation to the registration of common stock, preferred stock, debt securities, warrants and/or units of any combination thereof for the purposes of selling, from time to time, the Company’s common stock, debt securities or other equity securities in one or more offerings.

This S-3ASR became effective immediately.

We intend to convert the S-3ASR to S-3 by post-effective amendments in connection with the filing of this Annual Report.

The Company has a Sales Agreement with Cowen and Company, LLC (Cowen) to provide for the offering, issuance and sale of up to an aggregate amount of $ 200.0 million of common stock from time to time in “at-the-market” offerings (2024 ATM Program) pursuant to its S-3ASR, and subject to the limitations thereof.

In December 2024, the Company sold 1,225,000 shares pursuant to the 2024 ATM Program for net proceeds of $ 5,129 , after deducting commissions of $ 105 .

The Company previously had a Sales Agreement with Cowen to provide for the offering, issuance and sale of up to an aggregate amount of $ 100.0 million of common stock from time to time in “at-the-market” offerings (2023 ATM Program) pursuant to its shelf registration statement on Form S-3 (File No.

333-270599), which was declared effective April 26, 2023.

During the year ended December 31, 2023, the Company sold 4,760,899 shares pursuant to the 2023 ATM Program for net proceeds of $ 91,740 , after deducting commissions of $ 2,352 .

In the first quarter of 2024, the Company sold 258,070 additional shares, completing the 2023 ATM Program for net proceeds of $ 5,746 , after deducting commissions of $ 147 .

On March 31, 2025, the Company converted the Form S-3ASR to a Form S-3 (File No.

333-278126) by post-effective amendments.

This Form S-3 was declared effective on March 31, 2025.

The Company had a Sales Agreement with TD Securities (USA) LLC (as successor to Cowen and Company, LLC) (TD Cowen) to provide for the offering, issuance and sale of up to an aggregate amount of $ 200.0 million of common stock from time to time in “at-the-market” offerings (2024 ATM Program) pursuant to its S-3, and subject to the limitations thereof.

On June 11, 2025, the 2024 ATM Program with TD Cowen was terminated.

Prior to termination, the Company sold an aggregate of 2,609,865 shares pursuant to the 2024 ATM Program for total net proceeds of $ 7,724 , consisting of $ 5,129 in 202 4 and $ 2,595 in 2025.

On August 7, 2025, the Company filed a Registration Statement (File No.

333-289339) with the Securities and Exchange Commission (SEC), which was declared effective on August 15, 2025 (2025 Shelf Registration Statement), in relation to the registration of common stock, preferred stock, debt securities, warrants and/or units of any combination thereof for the purposes of selling, from time to time, the Company’s common stock, debt securities or other equity securities in one or more offerings.

The Company also simultaneously entered into a Sales Agreement with TD Cowen to provide for the offering, issuance and sale of up to an aggregate amount of $ 150.0 million of the Company's common stock from time to time in “at-the-market” offerings (the 2025 ATM Program) under the 2025 Shelf Registration Statement and subject to the limitations thereof (the 2025 Sales Agreement).

During the year ended December 31, 2025 , the Company sold 4,160,176 shares pursuant to the 2025 ATM Program for net proceeds of $ 10,151 .

Subsequent to December 31, 2025 , the Company sold 8,055,260 additional shares, for net proceeds of $ 22,568 .

2018 Stock Option and Grant Plan

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The Company generally granted stock-based awards with service conditions only (service-based awards), although there was one grant with performance conditions.

As of December 31, 2020, there are no unvested options with performance conditions.

As of December 31, 2020, there were no unvested options with performance conditions.

Stock options granted under the 2018 Plan generally vest over three to four years .

There were 1,959,411 options granted under the 2018 Plan prior to the Company’s IPO in October 2019.

A total of 1,959,411 options were granted under the 2018 Plan prior to the Company’s IPO in October 2019.

No further grants may be made under the 2018 Plan subsequent to the IPO.

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As of December 31, 2025 , there were 1,066,471 shares remaining available for issuance under the 2019 Plan.

A summary of the stock option activity is presented below:

2025 Inducement Plan

In October 2025, the Company adopted the 2025 Inducement Plan (Inducement Plan).

The Inducement Plan was adopted by the Compensation Committee of the Company’s board of directors without stockholder approval pursuant to Nasdaq Listing Rule 5635(c)(4).

In accordance with Rule 5635(c)(4), awards made under the Inducement Plan, including stock options and restricted stock units, may only be granted to newly hired employees as a material inducement to accept employment with the Company.

Stock options granted under the Inducement Plan expire no

later than ten years from the date of grant.

The number of shares reserved for issuance under the Inducement Plan was 275,000 shares.

As of December 31, 2025, there were no shares available for issuance under the Inducement Plan.

Stock Option Repricing

On May 19, 2025, the Company’s Board of Directors approved the repricing of certain outstanding vested and unvested stock options.

Pursuant to the repricing, all options granted under the 2018 Plan and 2019 Plan held by current employees, non-employee directors and certain consultants were repriced to $ 1.92 , the closing price of the Company’s common stock on May 19, 2025, to the extent such options had an exercise price in excess of 1.5x the $ 1.92 closing price per share.

To exercise the repriced options at the reduced exercise price, eligible participants must remain employed with the Company through a retention period of 12 months that begins on May 19, 2025.

As a result of the repricing, 9,900,096 vested and unvested stock options outstanding as of May 19, 2025, with original exercise prices ranging from $ 2.88 to $ 23.97 , were repriced.

The repricing resulted in incremental stock-based compensation expense of $ 3,021 , of which $ 1,813 related to vested stock option awards and is being amortized over the retention period, and $ 1,208 related to unvested stock option awards and is being amortized on a straight-line basis over the remaining vesting period of those awards.

Stock Option Activity

A summary of stock option activity is presented below:

Exercise Price (1)

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Options Exercisable at December 31, 2025

The aggregate intrinsic value of options granted is calculated as the difference between the exercise price of the options and the estimated fair value of the Company’s common stock.

The weighted average grant-date fair value of stock options granted during the year ended December 31, 2024 and 2023 was $ 13.44 and $ 9.51 , respectively.

(1) The weighted average exercise prices and aggregate intrinsic values in this table will not reflect the impact of the May 2025 repricing until the retention period is complete in May 2026.

The aggregate intrinsic value of options is calculated as the difference between the exercise price of the options and the fair value of the Company’s common stock.

The weighted average grant-date fair value of stock options granted during the years ended December 31, 2025 and 2024 was $ 1.52 and $ 13.44 , respectively.

The fair value of each award is estimated using Black-Scholes based on the following assumptions:

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The expected term for option grants is determined using the simplified method, which is the midpoint between the vesting period and the contractual term of the option.

Expected volatility —As a privately held company prior to the Company’s IPO in October 2019, the Company has limited trading history for its common stock and, as such, the expected volatility is estimated based on a weighted average volatility for the Company's stock price and comparable publicly traded biotechnology companies over a period equal to the expected term of the stock-based awards.

The comparable companies were chosen based on their similar size, stage in the life cycle or area of specialty.

The Company will continue to apply this process until a sufficient amount of historical information regarding the volatility of its own stock price becomes available.

Expected volatility —Expected volatility is estimated using the Company's stock price since its IPO in October 2019.

Risk-free interest rate —The risk-free interest rate is based on the U.S.

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The Company has recorded stock-based compensation in the accompanying statements of operations as follows:

Year Ended December 31,

Research and development

General and administrative

As of December 31, 2024, there was $ 51,239 of unrecognized compensation cost related to unvested option awards, which is expected to be recognized over a weighted-average period of 2.8 years.

As of December 31, 2025 , there was $ 35,159 of unrecognized compensation cost related to unvested option awards and vested option awards subject to the twelve month retention period, which is expected to be recognized over a weighted-average period of 2.1 years.

2019 Employee Stock Purchase Plan

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A total of 234,229 shares of common stock were initially reserved for issuance under the 2019 ESPP, and such number of shares will be increased each January 1 thereafter through January 1, 2029 by the least of (i) 234,229 shares of common stock, (ii) 1 % of the number of shares of the Company’s common stock outstanding on the immediately preceding December 31 or (iii) such lesser number of shares determined by the 2019 ESPP’s administrator.

There was no increase to the total number of shares available under the 2019 ESPP on January 1, 2024, 2023 or 2022, respectively.

On January 1, 2026, the total number of shares available under the 2019 ESPP was increased by 234,229 shares pursuant to the 2019 Plan Evergreen Provision.

As of December 31, 2025 , there were 136,383 shares remaining available for issuance under the 2019 ESPP.

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Year Ended December 31,

Expected income tax benefit at the federal statutory rate

State and local taxes, net of federal benefit

Research and development credit, net

Non-deductible items and other

Change in state and local tax rate

Change in valuation allowance

Statutory Tax Rate

State and Local Income Taxes, Net of Federal Income Tax Effect (1)

Foreign Tax Effects

Effect of Cross-Border Tax Laws

Change in Valuation Allowances (Domestic)

Nontaxable or Nondeductible Items

Other Adjustments

Actual income tax benefit effective tax rate

(1) Within the State Income Tax category, Pennsylvania and Philadelphia accounted for the majority, representing over 50% of the total reconciling impact.

Consistent with the Company’s cumulative loss position and absence of taxable income in federal, state, and local jurisdictions, the Company made no income tax payments and received no income tax refunds in the current fiscal year.

Deferred income taxes reflect the net effects of temporary differences between the carrying amounts of assets and liabilities for financial reporting purposes and the amounts used for income tax purposes.

The principal components of the Company’s deferred tax assets and liabilities consisted of the following:

Year Ended December 31,

Deferred tax assets:

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The local net operating losses begin to expire in 2042 .

As of December 31, 2024, the Company had federal and state research and development tax credit carryforwards of $ 15,684 and $ 612 , respectively, which begin to expire in 2038 and 2036 , respectively.

Under the provisions of Sections 382 and 383 of the Internal Revenue Code of 1986, as amended (the IRC), these net operating losses, credit carryforwards and other tax attributes may be subject to limitation based on previous significant changes in ownership and upon future significant changes in ownership of the Company, as defined by the IRC.

As of December 31, 2025 , the Company had federal and state research and development tax credit carryforwards of $ 25,044 and $ 6 , respectively.

The research and development credits begin to expire in 2038 .

The Company’s federal

research credits consist of approximately $ 13,821 of Research and Development credits and $ 11,223 of Orphan Drug credits.

Under the provisions of Sections 382 and 383 of the Internal Revenue Code of 1986, as amended, or the Code, these net operating losses, credit carryforwards and other tax attributes may be subject to limitation based on previous significant changes in ownership and upon future significant changes in ownership of the Company, as defined by the Code.

The Company files income tax returns in the U.S.

federal jurisdiction as well as in Pennsylvania and Philadelphia.

federal jurisdiction and in multiple state and local jurisdictions;

however, Pennsylvania and Philadelphia constitute the Company’s most significant tax jurisdictions due to the concentration of its operational footprint and the resulting apportionment profile.

The tax years 2024, 2023 and 2022 remain open to examination by the jurisdictions where the Company is subject to tax.

2 unchanged sentences

Net Loss Per Share

The Company calculates basic and diluted net loss per share in conformity with the two-class method required for participating securities.

For the year ended December 31, 2023, the Company had voting and non-voting common stock outstanding.

In May 2024, 1,444,295 shares of non-voting common stock was converted to voting common stock and as of December 31, 2024, no shares of non-voting common stock remain outstanding.

T he Company calculates basic and diluted net loss per share in conformity with the two-class method required for participating securities.

In May 2024, the remaining 1,444,295 shares of non-voting common stock were converted to voting common stock and no shares of non-voting common stock remain outstanding.

Since the rights of the voting and non-voting common stock are identical, except with respect to voting, the undistributed losses of the Company have been allocated on a proportionate basis to the two classes.

1 unchanged sentence

The weighted-average shares of common stock outstanding as of December 31, 2025 included outstanding pre-funded warrants to purchase up to an aggregate of 6,000,000 shares of common stock.

No pre-funded warrants remain outstanding as of December 31, 2024.

Diluted net loss per share is calculated using the if-converted method, which assumes conversion of all non-voting common stock to voting common stock.

No pre-funded warrants were outstanding as of December 31, 2024.

Diluted net loss per share is calculated using the if-converted method as of December 31, 2024, which assumes conversion of all non-voting common stock to voting common stock.

Year ended December 31, 2025

Voting common stock

Non-voting common stock

Basic net loss per share:

Allocation of undistributed losses

Weighted average number of shares used in basic per share computation

Net loss per share, basic

Diluted net loss per share:

Allocation of undistributed losses for basic computation

Reallocation of undistributed losses as a result of conversion of

non-voting to voting common shares

Allocation of undistributed losses

Weighted average number of shares used in basic per share computation

conversion of non-voting to voting common shares outstanding

Weighted average number of shares used in diluted per share computation

Net loss per share, diluted

Basic and diluted net loss per share:

Weighted average number of shares outstanding

Net loss per share, basic and diluted

Year ended December 31, 2024

15 unchanged sentences

The following outstanding potentially dilutive shares have been excluded from the calculation of diluted net loss per share, as their effect is anti-dilutive:

As of December 31,

Year Ended December 31,

Stock options to purchase common stock

Warrants to purchase common stock

401(k) Savings Plan

7 unchanged sentences

001-39103) filed on October 30, 2019)

Certificate of Amendment to the Third Amended and Restated Certificate of Incorporation of the Registrant (incorporated by reference to Exhibit 3.1 to the Registrant’s current report on Form 8-K (File No.

001-39103) filed with the SEC on June 10, 2025)

Amended and Restated Bylaws of the Registrant, as currently in effect (incorporated by reference to Exhibit 3.2 of the Registrant’s Current Report on Form 8-K (File No.

5 unchanged sentences

333-234017) filed on October 16, 2019 )

Description of Securities (incorporated by reference to Exhibit 4.3 to the Registrant’s Annual Report on Form 10-K (File No.

001-39103) filed on March 21, 2024)

Description of Securities

Form of Pre-Funded Warrant (incorporated by reference to Exhibit 4.1 of the Registrant's Current Report on Form 8-K (File No.

001-39103) filed with the SEC on December 12, 2022

Form of Pre-Funded Warrant (incorporated by reference to Exhibit 4.1 to the Registrant’s current report on Form 8-K (File No.

001-39103) filed with the SEC on June 12, 2025)

Form of Common Stock Warrant (incorporated by reference to Exhibit 4.2 to the Registrant’s current report on Form 8-K (File No.

001-39103) filed with the SEC on June 12, 2025)

2018 Stock Option and Grant Plan, as amended, and form of award agreements thereunder (incorporated by reference to Exhibit 10.1 of the Registrant’s Registration Statement on Form S-1 (File No.

12 unchanged sentences

Form of Indemnification Agreement between the Registrant and each of its executive officers (incorporated by reference to Exhibit 10.4 of the Registrant’s Registration Statement on Form S-1, filed with the SEC on September 30, 2019)

Cabaletta Bio, Inc.

2025 Inducement Plan

Amended and Restated License Agreement, dated as of July 23, 2019, among the Registrant, the Trustees of the University of Pennsylvania and the Children’s Hospital of Philadelphia (incorporated by reference to Exhibit 10.6 to the Registrant’s Registration Statement on Form S-1, filed with the SEC on September 30, 2019)

Master Translational Research Services Agreement, dated as of October 2018, between the Registrant and the Trustees of the University of Pennsylvania (incorporated by reference to Exhibit 10.9 to the Registrant’s Registration Statement on Form S-1, filed with the SEC on September 30, 2019)

CAROT Master Services Addendum to Master Translational Research Services Agreement, dated as of February 4, 2019, between the Registrant and the Trustees of the University of Pennsylvania (incorporated by reference to Exhibit 10.10 to the Registrant’s Registration Statement on Form S-1, filed with the SEC on September 30, 2019)

CVPF Master Services Addendum to Master Translational Research Services Agreement, dated as of October 22, 2018, between the Registrant and the Trustees of the University of Pennsylvania (incorporated by reference to Exhibit 10.11 to the Registrant’s Registration Statement on Form S-1, filed with the SEC on September 30, 2019)

5 unchanged sentences

Employment Agreement between the Registrant and David Chang (incorporated by reference to Exhibit 10.19 to the Registrant’s Registration Statement on Form S-1, filed with the SEC on September 30, 2019)

Fourth Amended and Restated Non-Employee Director Compensation Policy

Fourth Amended and Restated Non-Employee Director Compensation Policy (incorporated by reference to Exhibit 10.17 to the Registrant’s Annual Report on Form 10-K (File No.

001-39103) filed on March 31, 2025)

First Amendment, dated May 27, 2020, to the Amended and Restated License Agreement, dated July 23, 2019, among the Registrant, the Trustees of the University of Pennsylvania and the Children’s Hospital of Philadelphia (incorporated by reference to Exhibit 10.2 to the Registrant’s Current Report on Form 8-K (File No.

001-39103) filed on May 28, 2020)

Amendment to CAROT Master Services Addendum to Master Translational Research Services Agreement, dated as of May 18, 2020 between the Registrant and the Trustees of the University of Pennsylvania (incorporated by reference to Exhibit 10.1 to the Registrant’s Quarterly Report on Form 10-Q (File No.

001-39103) filed on August 6, 2020)

Second Amendment, dated October 19, 2021, to the First Amended and Restated License Agreement, dated May 27, 2020, among the Registrant, the Trustees of the University of Pennsylvania and the Children’s Hospital of Philadelphia (incorporated by reference to Exhibit 10.2 to the Registrant’s Quarterly Report on Form 10-Q (File No.

33 unchanged sentences

001-39103) filed on November 14, 2024)

Insider Trading Policy

Development and Manufacturing Services Agreement, dated as of December 19, 2024, between the Registrant and Lonza Houston Inc.

(incorporated by reference to Exhibit 10.1 to the Registrant's Quarterly Report on Form 10-Q (File No.

001-39103) filed on August 7, 2025)

Development and Manufacturing Services Agreement, dated as of January 11, 2026, between the Registrant and Cellares Corporation

Insider Trading Policy (incorporated by reference to Exhibit 19.1 to the Registrant’s Annual Report on Form 10-K (File No.

001-39103) filed on March 31, 2025)

List of Subsidiaries of the Registrant

53 unchanged sentences

Compared sentence by sentence after normalising whitespace, quotation marks, case and digits, so re-formatting and restated figures do not read as changed language. Wording changes appear as one removal and one addition. The current filing and the prior one are authoritative.

What changed 10-K

Item 9A. Controls and Procedures