allo-20251231

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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

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FORM 10-K

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(Mark One)

☒ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the fiscal year ended December 31, 2025

☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

FOR THE TRANSITION PERIOD FROM TO

Commission File Number 001-38693

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Allogene Therapeutics, Inc.

(Exact name of Registrant as specified in its Charter)

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210 East Grand Avenue, South San Francisco, California94080

(Address of principal executive offices including zip code)

Registrant’s telephone number, including area code: (650) 457-2700

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Securities registered pursuant to Section 12(b) of the Act:

Title of each class Trading symbol(s) Name of each exchange on which registered

Common Stock, Par Value $0.001 Per Share ALLO The Nasdaq Stock Market LLC

Securities registered pursuant to Section 12(g) of the Act: None

Indicate by check mark if the Registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act. Yes ☐ No ☒

Indicate by check mark if the Registrant is not required to file reports pursuant to Section 13 or 15(d) of the Act. Yes ☐ No ☒

Indicate by check mark whether the Registrant: (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the Registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes ☒ No ☐

Indicate by check mark whether the Registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the Registrant was required to submit such files). Yes ☒ No ☐

Indicate by check mark whether the Registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer”, “accelerated filer”, “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act.

Large accelerated filer ☐ Accelerated filer ☐

Non-accelerated filer ☒ Small reporting company ☒

Emerging growth company ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Indicate by check mark whether the registrant has filed a report on and attestation to its management’s assessment of the effectiveness of its internal control over financial reporting under Section 404(b) of the Sarbanes-Oxley Act (15 U.S.C. 7262(b)) by the registered public accounting firm that prepared or issued its audit report. ☐

If securities are registered pursuant to Section 12(b) of the Act, indicate by check mark whether the financial statements of the registrant included in the filing reflect the correction of an error to previously issued financial statements. ☐

Indicate by check mark whether any of those error corrections are restatements that required a recovery analysis of incentive-based compensation received by any of the registrant’s executive officers during the relevant recovery period pursuant to § 240.10D-1(b). ̈

Indicate by check mark whether the Registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). Yes ☐ No ☒

The aggregate market value of the voting and non-voting common equity held by non-affiliates of the registrant as of June 30, 2025 (the last business day of the registrant’s most recently completed second fiscal quarter) was approximately $184 million based on the closing price of the registrant’s common stock on June 30, 2025 of $1.13 per share, as reported by The Nasdaq Global Select Market.

The number of shares of Registrant’s Common Stock outstanding as of March 10, 2026 was 243,777,920.

DOCUMENTS INCORPORATED BY REFERENCE

Portions of the Registrant’s Definitive Proxy Statement relating to the 2026 Annual Meeting of Stockholders, which will be filed with the Securities and Exchange Commission on or before April 30, 2026, are incorporated by reference into Part III of this Annual Report.

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PART I

Item 1. Business 5

Item 1A. Risk Factors 39

Item 1B. Unresolved Staff Comments 87

Item 1C. Cybersecurity 87

Item 2. Properties 88

Item 3. Legal Proceedings 88

Item 4. Mine Safety Disclosures 88

PART II

Item 6. [Reserved] 91

Item 7A. Quantitative and Qualitative Disclosures About Market Risk 102

Item 8. Financial Statements and Supplementary Data 104

Item 9A. Controls and Procedures 138

Item 9B. Other Information 138

Item 9C. Disclosure Regarding Foreign Jurisdictions that Prevent Inspections 138

PART III

Item 10. Directors, Executive Officers and Corporate Governance 139

Item 11. Executive Compensation 139

Item 14. Principal Accounting Fees and Services 139

PART IV

Item 15. Exhibits, Financial Statement Schedules 140

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Unless the context requires otherwise, references in this report to “Allogene,” the “Company,” “we,” “us” and “our” refer to Allogene Therapeutics, Inc.

SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS

This Annual Report contains forward-looking statements. The forward-looking statements are contained principally in the sections entitled “Business,” “Risk Factors,” and “Management’s Discussion and Analysis of Financial Condition and Results of Operations”. These statements relate to future events or to our future financial performance and involve known and unknown risks, uncertainties and other factors which may cause our actual results, performance or achievements to be materially different from any future results, performance or achievements expressed or implied by the forward-looking statements. Forward-looking statements include, but are not limited to, statements about:

•the success, cost, timing and potential indications of our product development activities and clinical trials;

•the timing of the initiation, enrollment and completion of planned clinical trials in the United States and foreign countries;

•our ability to obtain and maintain regulatory approval of our product candidates in any of the indications for which we plan to develop them, and any related restrictions, limitations, and/or warnings in the label of an approved product candidate;

•our ability to obtain funding for our operations, including funding necessary to complete the clinical trials of any of our product candidates;

•our ability and plans to research, develop, manufacture and commercialize our product candidates;

•our ability to attract and retain collaborators with development, regulatory and commercialization expertise;

•the size of the markets for our product candidates, and our ability to serve those markets;

•our ability to successfully commercialize our product candidates;

•the rate and degree of market acceptance of our product candidates;

•our ability to develop and maintain sales and marketing capabilities, whether alone or with potential future collaborators;

•regulatory developments in the United States and foreign countries;

•our ability to contract with and the performance of our and our collaborators’ third-party suppliers and manufacturers;

•our ability to develop and successfully operate our own manufacturing facility;

•the success of competing therapies that are or become available;

•our ability to attract and retain key scientific or management personnel;

•the accuracy of our estimates regarding expenses, future revenues, capital requirements and needs for additional financing;

•our use of cash and other resources; and

•our expectations regarding our ability to obtain and maintain intellectual property protection for our product candidates and our ability to operate our business without infringing on the intellectual property rights of others.

In some cases, you can identify these statements by terms such as “anticipate,” “believe,” “could,” “estimate,” “expects,” “intend,” “may,” “plan,” “potential,” “predict,” “project,” “should,” “will,” “would” or the negative of those terms, and similar expressions that convey uncertainty of future events or outcomes. These forward-looking statements reflect our management’s beliefs and views with respect to future events and are based on estimates and assumptions as of the date of this report and are subject to risks and uncertainties. In addition, statements that “we believe” and similar statements reflect our beliefs and opinions on the relevant subject. These statements are based upon information available to us as of the date of this Annual Report, and while we believe such information forms a reasonable basis for such statements, such information may be

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limited or incomplete, and our statements should not be read to indicate that we have conducted an exhaustive inquiry into, or review of, all potentially available relevant information. These statements are inherently uncertain and investors are cautioned not to unduly rely upon these statements. We discuss many of the risks associated with the forward-looking statements in this Annual Report in greater detail under the heading “Risk Factors.” Moreover, we operate in a very competitive and rapidly changing environment. New risks emerge from time to time. It is not possible for our management to predict all risks, nor can we assess the impact of all factors on our business or the extent to which any factor, or combination of factors, may cause actual results to differ materially from those contained in any forward-looking statements we may make. Given these uncertainties, you should not place undue reliance on these forward-looking statements.

You should carefully read this Annual Report and the documents that we reference in this Annual Report and have filed as exhibits to this Annual Report completely and with the understanding that our actual future results may be materially different from what we expect. We qualify all of the forward-looking statements in this Annual Report by these cautionary statements.

Except as required by law, we assume no obligation to update these forward-looking statements publicly, or to update the reasons actual results could differ materially from those anticipated in any forward-looking statements, whether as a result of new information, future events or otherwise.

Trademarks and Trade names

This Annual Report contains references to our trademarks and to trademarks belonging to other entities. Solely for convenience, trademarks and trade names referred to in this Annual Report, including logos, artwork and other visual displays, may appear without the ® or TM symbols, but such references are not intended to indicate, in any way, that their respective owners will not assert, to the fullest extent under applicable law, their rights thereto. We do not intend our use or display of other companies’ trade names or trademarks to imply a relationship with, or endorsement or sponsorship of us by, any other companies.

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RISK FACTOR SUMMARY

Below is a summary of the material factors that make an investment in our common stock speculative or risky. This summary does not address all of the risks that we face. Additional discussion of the risks summarized in this risk factor summary, and other risks that we face, can be found below under the heading “Risk Factors” under Item 1A of Part I of this Annual Report, and should be carefully considered, together with other information in this Annual Report before making investment decisions regarding our common stock.

Risks Related to Our Financial Position and Capital Needs

•We have incurred net losses in every period since our inception and anticipate that we will incur substantial net losses in the future.

•We will need substantial additional financing to develop our products and implement our operating plans. If we fail to obtain additional financing, we may be unable to complete the development and commercialization of our product candidates.

•We may fail to meet our publicly announced guidance or other expectations about our business, which would cause our stock price to decline.

Risks Related to Our Business and Industry

•Our product candidates are based on novel technologies, which makes it difficult to predict the time and cost of product candidate development and the likelihood of obtaining regulatory approval.

•Our business is highly dependent on the success of our lead product candidates. If we are unable to advance clinical development, obtain approval of and successfully commercialize our lead product candidates for the treatment of patients in approved indications, our business would be significantly harmed.

•Our product candidates may cause undesirable side effects or have other properties that have halted and could in the future halt their clinical development, prevent their regulatory approval, limit their commercial potential or result in significant negative consequences.

•Our clinical trials may fail to demonstrate the safety and efficacy of any of our product candidates, which would prevent or delay regulatory approval and commercialization.

•Risks related to serious adverse events (SAEs) in the discontinued fludarabine, cyclophosphamide, and ALLO-647 (FCA) arm of our ALPHA3 trial, including the Grade 5 SAE, could lead to regulatory actions, negative perceptions, and potential product liability claims.

•No CAR T therapy has been approved as a part of first-line consolidation strategy for the treatment of large B-cell lymphoma (LBCL) patients, which presents significant regulatory, commercial, and operational risks, and there is no assurance of success in this unproven setting.

•We may encounter substantial delays in our clinical trials, or may not be able to conduct our trials on the timelines we expect.

•If we encounter difficulties enrolling patients in our clinical trials, our clinical development activities could be delayed or otherwise adversely affected.

•We may fail to successfully manufacture our product candidates, operate our own manufacturing facility, or obtain regulatory approval to utilize or commercialize from our manufacturing facility or at a CDMO, which could adversely affect our clinical trials and the commercial viability of our product candidates.

•Reduced manufacturing operations may limit our ability to timely support our development programs.

•We face significant competition from other biotechnology and pharmaceutical companies, and our operating results will suffer if we fail to compete effectively.

•We are highly dependent on our key personnel, and if we are not successful in attracting and retaining highly qualified personnel, we may not be able to successfully implement our business strategy.

•Disruptions to the operations of the FDA, the SEC and other government agencies, including comparable foreign regulatory authorities, resulting from funding shortages, policy initiatives, staffing reductions or related uncertainty, could impair their ability to perform regulatory functions and negatively impact our business.

Risks Related to the Development of Our Product Candidates

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•Our engineered allogeneic T cell product candidates represent a novel approach to cancer treatment and treatment of autoimmune diseases, which creates significant challenges for us.

•Gene-editing is a relatively new technology, and if we are unable to use this technology in our intended product candidates, our revenue opportunities will be materially limited.

•There is uncertainty regarding whether the use of fludarabine and cyclophosphamide (FC) without ALLO-647 will achieve sufficient lymphodepletion to support the efficacy of our allogeneic CAR T product candidate in the ALPHA3 trial.

•We are heavily reliant on our partners, Cellectis and Servier, for access to TALEN gene editing technology for the manufacturing and development of our oncology product candidates.

•We are heavily reliant on our partner, Foresight Diagnostics, for access to their CLARITYTM MRD test for identifying eligible patients for our ALPHA3 trial.

Risks Related to Our Reliance on Third Parties

•We rely and will continue to rely on third parties to conduct our clinical trials. If these third parties do not successfully carry out their contractual duties or meet expected deadlines, we may not be able to obtain regulatory approval of or commercialize our product candidates.

Risks Related to Government Regulation

•The FDA and other comparable foreign regulatory approval processes are lengthy and time-consuming, and we may experience significant delays in the clinical development and regulatory approval of our product candidates.

•The FDA or comparable foreign regulatory authorities may disagree with our regulatory plan and we may fail to obtain regulatory approval of our CAR T cell product candidates.

•If we, or our collaborators, are required by the FDA, or comparable foreign regulatory authorities, to obtain approval (or clearance, or certification) of a companion diagnostic device in connection with approval of one of our product candidates, and we, or our collaborators, do not obtain, or face delays in obtaining, approval (or clearance, or certification) of a companion diagnostic device, we will not be able to commercialize the product candidate, and our ability to generate revenue will be materially impaired.

Risks Related to Our Intellectual Property

•We depend on intellectual property licensed from third parties and termination of any of these licenses could result in the loss of significant rights, which would harm our business.

•If our efforts to protect the proprietary nature of the intellectual property related to our technologies are not adequate, we may not be able to compete effectively in our market.

Risks Related to Ownership of Our Common Stock

•The price of our stock has been and may continue to be volatile, and you could lose all or part of your investment.

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PART I

Item 1. Business

Overview

We are a clinical stage immuno-oncology company pioneering the development of genetically engineered allogeneic T cell product candidates for the treatment of cancer and autoimmune diseases. We are developing a pipeline of “off-the-shelf” T cell product candidates that are designed to target and kill cancer cells in patients or eliminate pathogenic autoreactive cells in patients with autoimmune disorders. Our engineered T cells are allogeneic, meaning they are derived from healthy donors for intended use in any patient, rather than from an individual patient for that patient’s use, as in the case of autologous T cells. We believe this key difference will enable us to deliver readily available treatments faster, more reliably, at greater scale, and to more patients.

After nearly eight years of platform development and treatment of more than 200 patients across six clinical studies, multiple anticipated clinical readouts are expected in the second quarter of 2026. These readouts could begin to validate several key scientific and clinical assumptions underlying off-the-shelf CAR T therapy, including biologic activity, safety, and the feasibility of standardized, readily available cell therapy across oncology and autoimmune indications.

We continue to focus on three core programs:

1.Large B-Cell Lymphoma (LBCL): Potentially groundbreaking ALPHA3 Trial that we believe may leapfrog other CAR T’s and embed cemacabtagene ansegedleucel (cema-cel, previously ALLO-501A) in first line (1L) LBCL treatment in community cancer centers where most newly diagnosed patients seek care.

2.Autoimmune Disease (AID): ALLO-329, our next-generation CD19 Dagger® program, focuses on scalability and reduced or chemotherapy-free lymphodepletion, positioning allogeneic CAR T to potentially transform autoimmune management and meet the demand of the market.

3.Renal Cell Carcinoma (RCC): TRAVERSE trial with ALLO-316 seeks to advance scientific innovation underlying the Dagger® technology to optimize CAR T cell expansion and persistence, thereby maximizing the potential of allogeneic CAR T in solid tumors.

Our allogeneic approach involves engineering healthy donor T cells, which we believe will allow for the creation of an inventory of off-the-shelf products that can be delivered to a larger portion of eligible patients throughout the world. These potential benefits led our Executive Chair, Arie Belldegrun, M.D., who was previously the Chair and Chief Executive Officer at Kite Pharma (Kite, now a Gilead company), and our President and Chief Executive Officer, David Chang, M.D., Ph.D., previously Chief Medical Officer and Executive Vice President of Research and Development at Kite, to found our company with the driving purpose of accelerating the development of allogeneic CAR T cell therapies.

Although we are currently focusing on our three core development programs noted above, we continue to build a pipeline to further the research and development of allogeneic CAR T cell product candidates in both hematological malignancies and solid tumors, as well as in autoimmune diseases. We believe our technology platform combined with our management team’s experience in immuno-oncology and specifically in CAR T cell therapy will help drive the rapid development and, if approved, the commercialization of potentially curative therapies for patients with aggressive cancer or who suffer from autoimmune diseases.

Our Approach

Our allogeneic CAR T cell development strategy has four key pillars: (1) engineering product candidates to minimize the risk of graft-versus-host disease (GvHD), a condition where allogeneic T cells can recognize the patient’s normal tissue as foreign and cause damage, (2) creating a window of persistence that may enable allogeneic T cells to expand and eradicate cancer cells or pathogenic autoreactive cells in patients, (3) building a leading manufacturing platform to enable consistent and high quality production and (4) leveraging next generation technologies to improve the functionality of allogeneic CAR T cells.

We use Cellectis, S.A. (Cellectis), TALEN® gene-editing technology and Arbor Biotechnologies CRISPR-based gene-editing technology in our oncology and autoimmune programs, respectively, to limit the risk of GvHD by engineering T cells to lack functional T cell receptors (TCRs), thereby preventing them from recognizing a patient’s normal tissue as foreign. We also utilize either standard lymphodepletion (e.g., fludarabine and cyclophosphamide (Flu/Cy)) and/or our Dagger® technology in our oncology and autoimmune programs to potentially enhance the expansion and persistence of our engineered allogeneic T cells. The Dagger® technology incorporates an anti-CD70 CAR engineered to eliminate CD70-expressing activated host T cells (including alloreactive host T cells) that can mediate premature rejection of infused allogeneic CAR T

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cells. We believe these approaches could enable a window of persistence for the infused allogeneic T cells to actively target and destroy cancer cells or to eliminate pathogenic autoreactive immune cells in autoimmune disease. Our off-the-shelf approach is dependent on state-of-the-art manufacturing processes, and we believe we have built a technical operations organization with fully integrated in-house expertise in clinical and commercial engineered T cell manufacturing.

For our lead autoimmune program, we have a non-exclusive license with Arbor Biotechnologies relating to a CRISPR-based gene-editing technology for the development of allogeneic T cell product candidates directed against various targets, including CD19 and CD70 both of which ALLO-329 targets.

We have built our own current good manufacturing practices (cGMP) manufacturing facility in Newark, California, that we call Cell Forge 1 (CF1). We exclusively utilize CF1 for manufacturing of our product candidates for use in clinical studies.

Our Pipeline

We are currently developing a pipeline of multiple allogeneic CAR T cell product candidates utilizing protein engineering, gene editing, gene insertion and advanced proprietary T cell manufacturing technologies. Our most advanced product candidate, cemacabtagene ansegedleucel, referred to as cema-cel (previously ALLO-501A), is an engineered allogeneic CAR T cell product candidate that targets CD19, a protein expressed on the cell surface of B cells and a validated target for B cell-derived hematological malignancies. We are currently focused on developing cema-cel for LBCL. Our pipeline also includes ALLO-316 and ALLO-329.ALLO-316 is an engineered allogeneic CAR T cell product candidate that targets CD70, which is highly expressed in RCC and is selectively expressed in several other cancers thereby creating the potential for ALLO-316 to be developed across a variety of both hematologic malignancies and solid tumors. We are currently focused on developing ALLO-316 for RCC. ALLO-329, an engineered allogeneic CAR T cell product candidate that targets both CD19 and CD70, is in development for the treatment of systemic lupus erythematosus (SLE), idiopathic inflammatory myopathies (IIM), and systemic sclerosis (SSc). We have additional product candidates, but we have deprioritized these programs to allow us to focus on cema-cel, ALLO-316 and ALLO-329. Our pipeline is represented in the diagram below.

1Phase 2 designed to be registrational

Our lead product candidates include:

•Cemacabtagene ansegedleucel (cema-cel). We continue to enroll our pivotal Phase 2 clinical trial (ALPHA3) for cema-cel as part of a 1L treatment plan for newly diagnosed and treated LBCL patients who are likely to relapse and need further therapy. The design of the ALPHA3 1L consolidation trial builds upon the results demonstrated in the Phase 1 ALPHA2 trial and leverages an investigational diagnostic test developed by Foresight Diagnostics, Inc. (Foresight Diagnostics), which was acquired by Natera, Inc. (Natera) in December 2025. We believe the Foresight Diagnostics assay will identify patients who have achieved remission by standard disease assessment but who have minimal residual disease (MRD) at the completion of 1L chemoimmunotherapy. The ALPHA3 trial is designed to

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evaluate whether treating MRD positive LBCL patients with cema-cel will improve clinical outcomes. The study will randomize approximately 220 patients who achieve a complete response or partial response to 1L therapy, but who are MRD positive. Patients are being randomized to receive either consolidation with cema-cel or the current standard of care, which is observation. The study design has event free survival (EFS) as its primary endpoint. Originally, the study design also included two lymphodepletion arms, FCA (standard fludarabine and cyclophosphamide plus ALLO-647) and FC (standard fludarabine and cyclophosphamide without ALLO-647). Following a Grade 5 treatment-related serious adverse event observed in the FCA arm, in August 2025 we announced the discontinuation of dosing in the FCA arm, and we terminated further development of ALLO-647. Thereafter, the trial design was amended and ALPHA3 is now proceeding with the FC arm and the control arm (observation).

An interim futility analysis will occur once 12 patients in each arm have been enrolled and followed for MRD conversion. We plan to announce MRD clearance data from the interim futility analysis in April 2026, and anticipate that enrollment in ALPHA3 will be completed by the end of 2027.

•ALLO-316. We have completed enrollment in a Phase 1 clinical trial (TRAVERSE) of ALLO-316, an allogeneic CAR T cell product candidate targeting CD70, in adult patients with advanced or metastatic RCC. We presented updated results from the TRAVERSE trial at the 2025 American Society of Clinical Oncology (ASCO) Annual Meeting in June 2025. Refer to “—Product Pipeline and Development Strategy—Anti-CD70 Development Program—Results from the Phase 1 ALLO-316 TRAVERSE Trial” for information regarding the results. In October 2024, we announced that we received Regenerative Medicine Advanced Therapy (RMAT) designation for ALLO-316 for adult patients with advanced or metastatic RCC. The RMAT designation was based on Phase 1 clinical data from the TRAVERSE trial indicating the potential of ALLO-316 to address the unmet need for patients with difficult-to-treat RCC who have failed multiple standard RCC therapies, including an immune checkpoint inhibitor and a VEGF-targeting therapy. We are currently exploring partnering opportunities to advance the asset.

•ALLO-329. During 2025, we initiated a Phase 1 clinical trial (the RESOLUTION trial) of ALLO-329, an allogeneic CAR T cell product candidate targeting both CD19 and CD70, in adult patients with systemic lupus erythematosus, including lupus nephritis, idiopathic inflammatory myopathies, and systemic sclerosis. Inclusion of an anti-CD70 CAR in ALLO-329 incorporates the Dagger® technology, which is designed to reduce or eliminate the need for standard chemotherapy by preventing premature rejection while targeting CD19+ B-cells and CD70+ activated T-cells, both of which play a role in autoimmune diseases. The RESOLUTION trial includes two distinct lymphodepletion arms: one using a dose of cyclophosphamide alone which is used by rheumatologists, and another that eliminates lymphodepletion entirely. We plan to announce initial proof-of-concept data in June 2026.

•Other Product Candidates: While we have additional programs in our pipeline, our development priorities are focused on cema-cel (1L consolidation in LBCL), ALLO-316, and ALLO-329. We will explore opportunities to partner with collaborators on product candidates across our pipeline.

Our History and Team

We believe we have established a leadership position in allogeneic CAR T cell therapy. In April 2018, we acquired certain assets from Pfizer Inc. (Pfizer), including strategic license and collaboration agreements and other intellectual property related to the development and administration of allogeneic CAR T cells for the treatment of cancer. We have an Exclusive License and Collaboration Agreement (the Servier Agreement) with Les Laboratoires Servier SAS and Institut de Recherches Internationales Servier SAS (collectively, Servier) to develop and commercialize cema-cel, and certain additional product candidates, and we hold the commercial rights to these product candidates in the United States, the European Union, and the United Kingdom. The Servier Agreement gives us access to Cellectis’ TALEN® gene-editing technology for cema-cel. We also have an exclusive worldwide oncology license from Cellectis to use its TALEN® gene-editing technology for the development of allogeneic T cell product candidates directed against 15 different cancer antigens, including CD70 which ALLO-316 targets. We also have a non-exclusive license with Arbor Biotechnologies relating to a CRISPR-based gene-editing technology for the development of allogeneic T cell product candidates in the field of autoimmune diseases directed against various targets, including CD19 and CD70, both of which ALLO-329 targets.

Our world-class management team has significant experience in immuno-oncology and in progressing products from early-stage research to clinical trials, and ultimately to regulatory approval and commercialization. In particular, both Dr. Belldegrun and Dr. Chang led the development and approval of Yescarta® at Kite. Additionally, our Executive Vice President of Research and Development and Chief Medical Officer, Dr. Zachary Roberts, was also instrumental in the development and execution of the clinical trials of Yescarta® across multiple indications.

Our Strategy

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Our goal is to maintain and build upon our leadership position in allogeneic CAR T cell therapy. We plan to rapidly develop and, if approved, commercialize allogeneic CAR T cell products for the treatment of cancer and autoimmune disease that can be delivered faster, more reliably, and at greater scale than autologous T cell therapies. We believe achieving this goal could result in allogeneic CAR T therapy becoming a standard of care in cancer and autoimmune disease treatments and enable us to make potentially curative products more readily accessible to more patients throughout the world. Key elements of our strategy include:

•Repositioning our allogeneic CAR T product as the only CAR T to be part of a first-line (1L) consolidation approach. We seek to redefine the future of CAR T by potentially repositioning our allogeneic CAR T product as the only CAR T to be part of a first line (1L) treatment plan for newly diagnosed and treated LBCL patients who are likely to relapse and need further therapy. The design of the ALPHA3 1L consolidation trial builds upon the results demonstrated in the Phase 1 ALPHA2 trial and leverages an investigational diagnostic test developed by Foresight Diagnostics to identify patients who have MRD at the completion of 1L chemoimmunotherapy for treatment with cema-cel. The ALPHA3 trial was initiated in June 2024 and now has over 60 sites activated and screening for patients with MRD. We plan to announce MRD clearance data from the interim futility analysis in April 2026, and anticipate that enrollment in ALPHA3 will be completed by the end of 2027.

•Expand our allogeneic CAR T platform into the treatment of autoimmune disease (AID). We are currently developing a next-generation product candidate, ALLO-329, which is an engineered allogeneic CAR T cell product candidate that targets CD19 and CD70. ALLO-329 incorporates our Dagger® technology. During 2025 we initiated a rheumatology basket study of ALLO-329, our RESOLUTION trial. Inclusion of an anti-CD70 CAR in ALLO-329 incorporates the Dagger® technology, which is designed to reduce or eliminate the need for standard chemotherapy by preventing premature rejection while targeting CD19+ B-cells and CD70+ activated T-cells, both of which play a role in autoimmune diseases. The RESOLUTION trial includes two parallel cell dose escalation arms that differ in the lymphodepletion regimen used. One arm uses cyclophosphamide alone at a dose used by rheumatologists, and the other does not incorporate lymphodepletion. We plan to announce initial proof-of-concept data in June 2026.

•Build state-of-the-art gene engineering and cell manufacturing capabilities. Manufacturing allogeneic T cell product candidates involves a series of complex and precise steps. We believe a critical component to our success will be to leverage and expand our proprietary manufacturing know-how, expertise and capacity. For instance, for our lead product candidate, cema-cel, we were able to identify and select a manufacturing process that was associated with robust clinical performance in Phase 1. We believe establishing our own fully integrated manufacturing operations and infrastructure will allow us to continuously improve the manufacturing process, limit our reliance on contract development and manufacturing organizations (CDMOs) and more rapidly advance the commercialization of any of our product candidates that receive regulatory approval.

•Expand into solid tumor indications with high unmet need and leverage next generation technologies to advance our platform. We plan to continue to advance the research and development of ALLO-316, which targets CD70, for the treatment of clear cell renal cell carcinoma (ccRCC). We are investigating next-generation technologies incorporated in the design of ALLO-316 which seek to better control rejection of allogeneic CAR T cells by the patient's immune system. Such technologies include our Dagger® technology that utilizes an anti-CD70 CAR to kill alloreactive host T cells. We continually survey the scientific and industry landscape for opportunities to license, partner or acquire technologies that may help us advance current or new cell therapies for the benefit of patients.

Allogeneic CAR T Cell Therapy

Engineered T Cell Therapies

T cells are a type of white blood cell and are involved in both sensing and killing infected or abnormal cells, including cancer cells, as well as coordinating the activation of other cells in an immune response. Engineered T cell therapy is a type of immunotherapy treatment whereby human T cells are removed from the body and engineered to express CARs which, when infused into a patient, may allow the recognition and destruction of cancer cells in a targeted manner.

Chimeric Antigen Receptors (CARs)

CARs are engineered molecules that, when present on the surface of a T cell, enable the T cell to recognize specific proteins or antigens that are present on the surface of other cells. More than one type of CAR can be included in a CAR T cell, imparting multi-antigen targeting capability. The CAR molecule(s) in our product candidates are comprised of a single chain protein that contains the following elements:

•Target Binding Domain: At one end of the CAR is a target binding domain that is specific to a target antigen. This domain extends out onto the surface of the engineered T cell, where it can recognize the target antigens. The target

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binding domain consists of a single-chain variable fragment (scFv) of an antibody comprising variable domains of heavy and light chains joined by a short linker.

•Transmembrane Domain and Hinge: This middle portion of the CAR links the scFv target binding domain to the activating elements inside the cell. This transmembrane domain “anchors” the CAR in the cell’s membrane. In addition, the transmembrane domain may also interact with other transmembrane proteins that enhance CAR function. The hinge domain, which extends to the exterior of the cell, connects the transmembrane domain to scFv and provides structural flexibility to facilitate optimal binding of scFv to the target antigen on the cancer cell’s surface.

•Activating Domains: The other end of transmembrane domain, inside the T cell, is connected to one or more signaling domains responsible for activating the T cell when the CAR binds to the target cell. The CD3 zeta domain delivers an essential primary signal within the T cell, and the 41BB domain delivers an additional, co-stimulatory signal. Together, these signals trigger T cell activation, resulting in proliferation of the CAR T cells and killing of the cancer cell. In addition, activated CAR T cells stimulate the local secretion of cytokines and other molecules that can recruit and activate additional immune cells to potentiate killing of the cancer cells.

In addition to the domains described above, in ALLO-316, we have included rituximab recognition domains to potentially serve to identify and/or eliminate ALLO-316 cells using rituximab. The figure below shows the constructs that support our lead product candidates in clinical development: cema-cel, ALLO-316 and ALLO-329.

Allogeneic CAR T Cell Products: The Next Revolution

There are two primary ex vivo approaches to engineered T cell therapy: autologous and allogeneic. Autologous therapies use engineered T cells derived from the individual patient, while allogeneic products use engineered T cells derived from unrelated healthy donors. While the autologous approach has been revolutionary, demonstrating compelling efficacy in many patients, it is burdened by the following key limitations:

•Lengthy Delivery Time. Due to the individualized manufacturing process, patients may wait weeks to months to be treated with their engineered cells. As a result, in the registrational trials for Yescarta® and Kymriah®, up to 31% of intended patients ultimately did not receive treatment primarily due to complications from the underlying disease prior to delivery of therapy or as a result of manufacturing failures. In addition, certain patients being treated with autologous therapies have sometimes required bridging therapy as they wait for the manufacture of their T cells, however, bridging therapy to control disease may increase some cumulative or synergistic toxicities for the patients. Other rapidly progressing patients may not be considered candidates for autologous CAR T given lengthy waiting times and limited manufacturing slots. Each of these autologous CAR T challenges creates inherent limitations to the uptake of autologous CAR T therapies. As discussed in more detail below, these limitations become increasingly prohibitive in diseases where time is of the essence as is the case in 1L consolidation, making autologous CAR T therapy unsuitable for such use.

•Variable Potency. In some cases, patients may have T cells that have been damaged or weakened due to prior chemotherapy or hematopoietic stem-cell transplant. Compromised T cells may not proliferate well during manufacturing or may produce cells with insufficient potency that cannot be used for patient treatment, resulting in manufacturing failures, or that can show poor expansion and activity in patients. In addition, the individualized nature of autologous manufacturing, together with the variability in patients’ T cells, may lead to variable potency of manufactured T cells, and this variability may cause unpredictable treatment outcomes.

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•Manufacturing Failures. Autologous cell manufacturing sometimes encounters production failures. This can mean that a patient never receives treatment, as additional patient starting material may not be available or the patient may no longer be eligible due to advanced disease. Furthermore, retreatment can be difficult due to a limited supply of usable patient starting material.

•Complex Logistics. The delivery of autologous T cell therapy is complicated due to the individualized nature of manufacturing, which allows only one patient to be treated from each manufacturing run and requires dedicated infrastructure to maintain a strict chain of custody and chain of identity of patient-by-patient material collection, manufacturing and delivery. The complex logistics add significant cost to the process and limit the ability to scale. Additionally, the collection of T cells through leukapheresis from each individual patient results in a time consuming and costly step in the autologous process. In part due to these logistics, autologous treatment is currently only available at select centers.

In addition to these ex vivo approaches, a third approach has emerged that is referred to as in vivo CAR T or in situ CAR T. This in vivo approach seeks to generate CAR expressing T cells directly inside the patient by administering engineered delivery systems (such as viral vectors or targeted lipid nanoparticles (LNP)) that introduce CAR encoding genetic material into endogenous T cells. We believe that in vivo approaches face limitations/challenges, including:

•CAR expression and transduction efficiency are dose dependent and difficult to titrate (unpredictable pharmacology).

•Potential immunogenicity to LNP components or viral proteins may hinder repeat dosing or retreatment.

•Reduced activity in patients with exhausted or otherwise unhealthy T cells.

•Risk of off target delivery and insertional mutagenesis in progenitor cells arising from stochastic viral vector integration, warranting monitoring.

Allogeneic engineered T cells are manufactured in a similar manner as autologous, but our manufacturing has two key differences: (1) our allogeneic T cells are derived from healthy donors, not the patients themselves, and (2) our allogeneic T cells are genetically engineered to minimize the risk of GvHD.

Our approach is designed to provide the same intended curative outcome as autologous therapy, while offering the following potential key advantages:

•Availability and Access. Starting with T cells from a healthy donor, we believe that at scale we can manufacture approximately 100 doses or more of allogeneic CAR T product per manufacturing run that could be used in any eligible patient. Because our allogeneic product candidates are designed to be frozen and available off-the-shelf, they are expected to be readily shipped and administered to patients.

•Speed to Patient. Many patients with aggressive or rapidly progressing cancer may not have multiple weeks to wait for autologous CAR T treatment. Our allogeneic approach has the potential to create off-the-shelf product inventory, which could enable dosing of patients within days of a decision to treat. This would represent a significant reduction in patient wait time, potentially obviating the need for any bridging therapy and allowing the treatment of patients who are either too sick, or their disease progresses too quickly for them to wait for their autologous CAR T cells to be manufactured, thus potentially improving patient outcomes. In addition, as we seek to incorporate our investigational allogeneic CAR T product into a 1L consolidation strategy, the speed to patient becomes even more important. Once it is determined that a patient is MRD positive following standard 1L treatment, published results of front-line chemotherapy outcomes suggest that the patient is very likely to progress, and some patients may do so very quickly (i.e., within a matter of weeks after completing 1L therapy). Furthermore, data suggests that patients who have low burden of disease when they receive CAR T cells tend to have better safety and efficacy outcomes, including lower rates of cytokine release syndrome (CRS) and more durable remissions. As a result, we believe that autologous CAR T therapy is far less suitable for treating MRD positive patients as part of a 1L consolidation strategy given the lengthy lead time for the autologous individualized manufacturing process, which would not allow for rapid CAR T treatment before disease progression and while the disease burden remains low.

•Enhanced Cell Consistency and Potency. Our manufacturing process produces therapies from selected, screened and tested healthy donors. Healthy donor T cells are potentially superior for engineered cellular therapy as compared to T cells from patients who have undergone prior chemotherapy or hematopoietic stem-cell transplant, which can reduce in number, damage or weaken T cells, as may be the case with autologous or in vivo cell therapy. In addition, greater consistency of the product may yield more predictable treatment outcomes.

•Streamlined Manufacturing. We have built an efficient and scalable manufacturing process and organization. The allogeneic CAR T approach utilizes healthy donor T cells which we believe provides enhanced scalability, and an off-the-shelf capability that can potentially reduce the costs to the overall healthcare system as it does not require bridging therapy, leukapheresis and complex logistics.

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Manufacturing Allogeneic T Cells

There are similarities as well as key differences between the processes for allogeneic and autologous CAR T cell manufacturing. The three primary steps to creating our engineered allogeneic CAR T cells are: (1) collection and transduction, (2) gene editing, and (3) purification, formulation, and storage. We start with collecting white blood cells from a healthy donor, which are subsequently stimulated to proliferate and transduced with a viral vector to integrate the CAR sequence into the T cell genome. The CAR sequence directs the expression of CAR proteins on the cell surface that allows the transduced T cells to recognize and bind to a target molecule, for example a target that is present on cancer cells or pathogenic autoreactive immune cells. Next, we use gene editing tools to edit the T cell genome to inactivate TCRα, and in the case of our oncology products, to also inactivate CD52. Inactivation of TCRα is intended to reduce the risk of GvHD. Inactivation of CD52 was intended to enable the use of ALLO-647, a proprietary CD52 monoclonal antibody, as part of lymphodepletion. Although the CD52 inactivation remains in certain of our product candidates, we have now discontinued the use of ALLO-647 as we now do not believe it is a necessary component of the lymphodepletion regimen for our product candidates in the clinical settings selected for development. For oncology products the transduction and genetic editing steps are separate, but for our autoimmune disease product candidate, ALLO-329, the steps are combined and utilize different gene editing technology. Furthermore, ALLO-329 does not incorporate the CD52 knockout utilized in oncology products. Finally, the edited T cells are cultured for several days to increase the cell number, harvested and purified. The purified T cells are formulated in a cryopreservation media and filled into closed, stoppered vials prior to controlled-rate freezing and long-term storage in the vapor phase of liquid nitrogen. This inventory is securely stored and then shipped to treatment facilities, as needed.

Product Pipeline and Development Strategy

Using our proprietary allogeneic CAR T cell platform, we are researching and developing multiple product candidates for the treatment of blood cancers, solid tumors and autoimmune diseases. Our product candidates are allogeneic T cells engineered to be used as off-the-shelf treatments for any patient with a particular cancer type or autoimmune disease. Each product candidate bears specific engineered attributes, and targets a selected antigen expressed on tumor cells or pathogenic autoreactive immune cells.

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Our product pipeline is represented in the chart below:

1Phase 2 designed to be registrational

Anti-CD19 Oncology Development Program

CD19 is an antigen expressed on the surface of B cells, including on B cells that are malignant. B cells are considered non-essential tissue, as they are not absolutely required for patient survival. We believe CD19 is a validated target for the treatment of B cell leukemias and lymphomas. Multiple autologous anti-CD19 CAR T therapies have shown promising results and have been approved by the FDA as therapies in multiple blood cancers, including relapsed/refractory (R/R) LBCL, as further described below under "—Competition".

Historically, under our Servier Agreement, we have worked with Servier to develop several CD19 product candidates, including UCART19, ALLO-501 and cema-cel. On September 15, 2022, Servier sent us a notice of discontinuation of its involvement in the development of all CD19 Products pursuant to the Servier Agreement. On May 10, 2024, we entered into an Amendment and Settlement Agreement (the Servier Amendment) with Servier which restructures our relationship under the Servier Agreement. Under the Servier Amendment the parties agreed that co-development performed by the Company and Servier under the Servier Agreement, including co-development relating to CD19 Products, ceased as of December 15, 2022. In December 2025, the Centre de Médiation et d'Arbitrage de Paris issued a decision in an arbitration between Cellectis and Servier relating to Servier’s discontinuation of development. In that decision, the arbitration panel terminated Servier’s license to UCART19v1 and ALLO-501, which were essentially the same product, and as a result our license to ALLO-501 was also terminated. We had previously in 2021 terminated further development of ALLO‐501 in favor of ALLO‐501A, now known as cema‐cel, in view of ALLO‐501A’s optimized construct and manufacturing process, including removal of the rituximab-activated safety switch and promoter modifications that improved CAR expression, product consistency, and clinical scalability without altering the CAR itself. This termination of our rights with respect to ALLO-501 does not impact our license with respect to cema-cel, and we continue to have no plans to further develop ALLO-501.

We have been, and continue to be, responsible for the manufacture and clinical development of cema-cel. Cema-cel is manufactured to express a CAR that is designed to target CD19 and gene edited to lack TCRα and CD52 to minimize the risk of GvHD and enable use of anti-CD52 monoclonal antibodies to create a window of CAR T cell persistence in the patient, which is illustrated below.

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Lead Target Indication: Non-Hodgkin Lymphoma (NHL)

NHL is a hematologic cancer originating from lymphocytes. It is the most common hematological malignancy in the United States, with 80,620 new cases estimated to be diagnosed and 20,140 deaths estimated in 2024, according to the American Cancer Society. Over 60 NHL subtypes have been identified, and each subtype represents different neoplastic lymphoid cells (T, B or NK cells) that have arrested at different stages of differentiation. According to the American Cancer Society, B-cell lymphomas make up approximately 85% of NHL cases in the United States.

B-cell NHL itself represents a group of different neoplasms that not only differ in pathology, but also response to therapy and prognosis. NHL can be rapidly growing (aggressive), such as LBCLs, or it can be slow growing, or indolent, such as follicular lymphoma (FL).

The R-CHOP chemotherapy combination (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone), introduced in the early 2000s, remains the standard of care for newly diagnosed LBCL and can yield five-year survival rates of approximately 55-60%. Unfortunately, the remaining LBCL patients relapse or have treatment-refractory disease and require additional therapy. Historically, treatment options have included salvage chemotherapy followed by high-dose therapy and autologous stem-cell transplantation in eligible patients, as well as autologous anti-CD19 CAR T therapy. A retrospective analysis of patients with R/R LBCL, who were not treated with autologous CAR T therapy reported an objective response rate of 26% (complete response (CR): 7%, partial response: 18%) and median overall survival of 6.3 months. In recent years, additional therapies have been approved for patients with relapsed or refractory disease, including antibody-drug conjugates such as polatuzumab vedotin and loncastuximab tesirine, the CD19-directed antibody tafasitamab in combination with lenalidomide, and CD20-directed bispecific antibodies such as epcoritamab and glofitamab. Despite these advances, outcomes for many patients with relapsed or refractory LBCL remain poor.

Autologous CAR T therapy has made significant advances in addressing R/R NHL, and has moved to earlier lines of therapy, as further described below under — "Competition".

Results from the Phase 1 ALLO-501 ALPHA Trial and the Phase 1 cema-cel ALPHA2 Trial

On February 13, 2025, we announced long-term follow up data from the Phase 1 ALPHA trial of ALLO-501 and from the Phase 1 ALPHA2 trial of cema-cel in R/R LBCL which was published in the Journal of Clinical Oncology. The ALPHA/ALPHA2 studies were single-arm, multicenter, open-label, Phase 1 trials. As of the data cutoff date (September 26, 2024), 33 CD19 CAR T-naive patients with R/R LBCL were treated in ALPHA/ALPHA2 with cema-cel/ALLO-501 manufactured with the process selected for use in pivotal studies.

The overall Response Rate (ORR) and Complete Response (CR) rate in the ALPHA/ALPHA2 trials were comparable with those observed in patients with R/R LBCL after two or more lines of systemic therapy who received treatment with approved autologous CD19 CAR T cell products. All treatment regimens studied demonstrated clinical benefit. The selected Phase 2 regimen (fludarabine/cyclophosphamide lymphodepletion with 90 mg of ALLO-647 (FCA90) followed by a single dose of CAR+ cells) yielded the highest ORR and CR of 67% and 58%, respectively. Five of 12 patients in this group achieved CR that lasted at least 6 months.

Patients Treated with Phase 2 Regimen (n=12)

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Overall Response Rate (ORR), n (%) 8 (67)

Complete Response (CR), n (%) 7 (58)

6 Month CR Rate, n (%) 5 (42)

Patients who achieved a CR had excellent outcomes with a median DOR, PFS (progression free survival) and OS of 23.1 months, 24 months, and not reached, respectively. For patients receiving the selected Phase 2 regimen, median DOR was 23.1 months and median OS was not reached.

The safety profile, including incidence of cytopenias and infections, was manageable and consistent with that of approved autologous CD19 CAR T cell therapies. There were no dose-limiting toxicities, graft-versus-host disease (GvHD), immune effector cell-associated neurotoxicity syndrome (ICANS), or high-grade cytokine release syndrome (CRS). The most common any-grade treatment emergent adverse events (TEAE) (≥25%) were neutropenia (85%), anemia (67%), thrombocytopenia (58%), infusion-related reactions (IRRs; 58%), fatigue (52%), and pyrexia (49%), nausea (39%), lymphopenia (36%), hypotension (36%), peripheral edema (33%), decreased white blood cell count (30%), CMV reactivation (30%), decreased appetite (30%), chills (30%), and hypoxia (27%).

The median time to start of treatment was two days from study enrollment. In contrast, autologous CAR T cell products require wait times often longer than 1 month despite incremental advancements in manufacturing and supply chains.

A growing body of evidence indicates that treatment with CAR T at times when the disease burden is low leads to improved safety and efficacy outcomes and this study reported similar findings. Among patients with baseline tumor burden <1000 mm2 or normal serum lactate dehydrogenase (LDH), a blood test that indicates disease activity, the CR rate was 100% (6/6) and 82% (9/11), respectively. These CR rates in this subpopulation support cema-cel as a promising therapeutic option in patients with minimum residual disease (MRD), the population currently being studied in the ALPHA3 trial.

These results serve as the foundation for the ongoing ALPHA3 trial, which is evaluating cema-cel as a consolidation therapy in LBCL patients who are in remission following 1L treatment but remain positive for MRD as detected by an ultrasensitive ctDNA based blood test, Foresight Diagnostics’ investigational CLARITYTM , powered by PhasED-SeqTM. These patients have extremely low disease burden, a key subgroup who demonstrated excellent disease outcomes in the ALPHA/ALPHA2 trials.

Clinical Development Plan - Non-Hodgkin Lymphoma (NHL)

We are the sponsor of the ALPHA trial of ALLO-501 and ALPHA2 trial of cema-cel, each for patients with R/R NHL or CLL. The ALPHA trial is a Phase 1 clinical trial of ALLO-501 in patients withR/R LBCL and R/R FL. We completed accrual in the ALPHA trial in 2021 and are following patients as part of long-term follow-up. The ALPHA2 trial was initiated as a Phase 1/2 clinical trial for cema-cel in the second quarter of 2020. The Phase 1 portion of the ALPHA2 trial was designed to assess the safety and tolerability at increasing dose levels of cema-cel in patients with R/R LBCL. In the fourth quarter of 2022, we proceeded to the Phase 2 portion of the ALPHA2 trial in adult patients with R/R LBCL. We are the sponsor of the EXPAND trial of ALLO-647, which was intended to demonstrate the overall contribution of ALLO-647 to the risk-benefit ratio of the lymphodepletion regimen for cema-cel.

In January 2024 we announced that we would deprioritize the ALPHA2 R/R LBCL and EXPAND trials to focus on our ALPHA3 trial, which seeks to embed cema-cel as part of a 1L consolidation strategy. We have deprioritized the ALPHA2 R/R LBCL trial primarily because the ALPHA3 trial, if successful, could significantly impact the need for cell therapy in later lines of treatment, including the third line (3L) patients being studied in our ALPHA2 trial. The ALPHA3 trial is an open-label, Phase 2, multicenter clinical trial evaluating the safety and efficacy of cema-cel in adult patients with LBCL who have completed R-CHOP for other standard regimen and have attained a remission, but who test positive for MRD. The ALPHA3 trial will randomize approximately 220 patients who achieve a complete or partial response to 1L therapy, but who test positive for MRD at their end-of-therapy PET/CT assessment. The patients will be randomized to either treatment with cema-cel or the current standard of care, which is observation. The design, with a primary endpoint of EFS, initially included two lymphodepletion arms (one with standard fludarabine and cyclophosphamide plus ALLO-647 (FCA) and one without ALLO-647 (FC)). Following a Grade 5 treatment-related serious adverse event observed in the FCA arm, in August 2025 we announced the discontinuation of dosing in the FCA arm, and we terminated further development of ALLO-647. Thereafter, the trial design was amended and ALPHA3 is now proceeding with just the FC arm and the control arm (observation).

The ALPHA3 trial leverages an investigational diagnostic test developed by Foresight Diagnostics to identify patients who have MRD at the completion of 1L chemoimmunotherapy. Although 1L R-CHOP is curative for many with LBCL, as noted above, approximately 30% of patients treated will relapse. Under the current standard of care, there is no way to determine which patients are at greater risk of relapse after initially responding to 1L treatment, and so the standard of care has been simply to “watch and wait” for the disease to relapse. Foresight Diagnostics, however, has developed a liquid biopsy

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testing platform for the measurement of MRD. Based on Foresight Diagnostics’ published data, we believe that the Foresight Diagnostics’ assay is highly sensitive and predictive of which patients are likely to relapse. By incorporating the Foresight Diagnostics assay into our ALPHA3 trial design, we believe that we can identify the patient population most at risk for relapse and treat those patients with cema-cel. In February 2025, we entered into an Amended and Restated Strategic Collaboration Agreement with Foresight Diagnostics which expands our collaboration to enable the development of Foresight Diagnostics’ CLARITYTM MRD assay as a companion diagnostic in the EU, UK, Canada and Australia in support of Allogene’s clinical development of cema-cel. In December 2025, Foresight Diagnostics was acquired by Natera; however, it continues to operate as a standalone division of Natera and to execute its role in the ALPHA3 trial. To date, the acquisition has not impacted Foresight Diagnostics’ ability to meet its testing commitments or had any negative effect on the execution of the ALPHA3 trial, including enrollment and trial timelines.

ALPHA3 takes advantage of cema-cel as a one-time, off-the-shelf treatment that can be administered immediately upon discovery of MRD following six cycles of R-CHOP, potentially positioning cema-cel to become the standard “7th cycle” of frontline treatment available to all eligible patients with MRD. ALPHA3 builds on our belief that administration of CAR T therapies to patients with low disease burden improves both safety and efficacy outcomes. Cema-cel’s Phase 1 safety profile, with low rates of CRS and immune effector cell-associated neurotoxicity syndrome (ICANS), already permits its use in the outpatient setting in R/R patients and may further improve in patients with no radiological evidence of disease. The ALPHA3 trial was initiated in 2024 and enrollment is currently ongoing with over 60 sites activated in the United States and Canada. We expect to activate additional sites in Australia and South Korea in mid-2026. We have met with European Union (EU) regulatory authorities and have received scientific advice to assist us with finalizing our regulatory strategy for opening the trial in the EU, and operational feasibility assessments for the EU remain ongoing.

An interim futility analysis is expected to occur in April 2026 which will compare MRD clearance rates between cema-cel after standard fludarabine and cyclophosphamide (FC) lymphodepletion versus observation (12 patients in each arm). The update will also include a summary of safety outcomes and additional information about screening and treatment patterns across the trial site footprint. Clearance of MRD in 25–30% more patients assigned to the cema-cel arm compared to those in the observation arm may indicate a proof of concept that early treatment of MRD+ disease could meaningfully improve long term outcomes.

We anticipate that enrollment in ALPHA3 will be completed by the end of 2027. Assuming favorable outcomes and subject to FDA discussions, we plan to seek FDA approval of cema-cel based on the ALPHA3 trial. Additionally, assuming favorable outcomes, we anticipate that the ALPHA3 data set could be used to support EU regulatory approval regardless of whether the ALPHA3 trial is expanded into the EU. The EMA has granted Marketing Authorizations for products, even when their clinical development programs did not involve any European sites. These approvals are based on thorough evaluations of the products’ safety, efficacy, and quality. This practice encompasses a wide range of indications and modalities, including those classified as Advanced Therapy Medicinal Products by the EMA.

Anti-CD70 Oncology Development Program

CD70 is an antigen expressed on several types of cancer cells, with strong expression in RCC and limited off-tumor expression. CD70 is selectively expressed in a portion of other solid tumors and blood cancers.While CD70 can be expressed on activated T cells, ALLO-316 was associated with minimal or no fratricide in preclinical studies, meaning that ALLO-316 cells did not mediate the targeted killing of other ALLO-316 cells. Accordingly, we believe progressing allogeneic CAR T cell products directed against CD70 could be promising in solid tumor indications as well as hematological malignancies.

ALLO-316 is manufactured to express a CAR that is designed to target CD70 and gene edited to lack expression of the TCR to minimize the risk of GvHD. We also inactivated CD52, which was intended to enable use of CD52 monoclonal antibodies to potentially permit a window of persistence of CAR T cells in the patient. Although the CD52 edit remains in ALLO-316, we have discontinued dosing ALLO-316 in combination with an anti‐CD52 monoclonal antibody as we now do not believe it is a necessary component of the lymphodepletion regimen for ALLO-316. In addition, rituximab and CD34 recognition domains have been incorporated in between the scFv and the linker domain, as illustrated below. The rituximab recognition domains allow targeting of cells with rituximab in the event that silencing of CAR T cell activity is desired. The CD34 domain confers recognition by an anti-CD34 antibody, and may be used as a surface marker to monitor ALLO-316 in patients by flow cytometry.

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In the first half of 2021, we initiated Phase 1 TRAVERSE clinical trial of ALLO-316 in adult patients with advanced or metastatic ccRCC.

Lead Target Indication: Clear Cell Renal Cell Carcinoma

ccRCC is the most common subtype of renal cancer. Approximately 81,800 new cases of renal cell carcinoma are estimated to be diagnosed in the United States and 14,890 deaths are estimated in 2023, according to the American Cancer Society. The five-year survival rate for patients with advanced kidney cancer is less than 15%.

Systemic therapy (including immunotherapy and molecularly targeted agents), surgery, and radiation therapy all may have a role in the treatment paradigm depending on the extent of disease, sites of involvement, and patient-specific factors. While vascular endothelial growth factor (VEGF)-directed therapies (e.g. sunitinib) represented a first-line standard for over a decade, these therapies have been quickly supplanted by combination therapies incorporating PD-1 immune-checkpoint inhibition as the backbone.

The combination of VEGF and immune check-point inhibitors, such as axitinib and pembrolizumab, respectively, is often used in the first line setting and has shown a median progression-free survival of 15.1 months with an ORR of 59.3% and CR rate of 5.8%.Patients who progress on immune checkpoint-based combination therapies can be treated with agents including cabozantinib, lenvatinib with everolimus, tivozanib, belzutifan or other therapies.

In October 2024, we announced that we received Regenerative Medicine Advanced Therapy (RMAT) designation for ALLO-316 for adult patients with advanced or metastatic RCC. The RMAT designation was based on Phase 1 clinical data from the TRAVERSE trial indicating the potential of ALLO-316 to address the unmet need for patients with difficult-to-treat RCC who have failed multiple standard RCC therapies, including an immune checkpoint inhibitor and a VEGF-targeting therapy.

Results from the Phase 1 ALLO-316 TRAVERSE Trial

On June 1, 2025, we announced updated data from the Phase 1 TRAVERSE trial of ALLO-316 in patients with advanced or metastatic RCC whose tumors had progressed on or who are intolerant to standard therapies, including an immune checkpoint inhibitor and a VEGF-targeting therapy. The data were presented at the 2025 ASCO Annual Meeting and focused on the Phase 1b expansion cohort evaluating ALLO-316 at DL2 (80 million CAR T cells) following a standard lymphodepletion regimen of fludarabine (30 mg/m2/day) and cyclophosphamide (500 mg/m2/day) for three days. The median time from enrollment to the start of therapy was four days.

In the Phase 1b expansion cohort, 22 patients whose tumors had progressed on multiple prior therapies were treated with lymphodepletion and 20 were treated with ALLO-316. All patients had tumors resistant to immune checkpoint blockers and at least one tyrosine kinase inhibitor (TKI), 82% had ≥2+ prior TKIs, and 41% had prior belzutifan. Sixteen of the ALLO-316 treated patients had a high CD70 Tumor Proportion Score (TPS >50%).

A single dose of ALLO-316 stabilized or reversed disease progression in the majority of patients. In the 16 patients with CD70 TPS ≥50%, the trial demonstrated a Confirmed Overall Response Rate (ORR) of 31%. Of the five confirmed responders, four maintain ongoing responses, with one in sustained remission for over 12 months. The median duration of response (mDOR) has not yet been reached, indicating the potential for long-term disease control.

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The updated results continue to demonstrate the potential of an allogeneic CAR T product candidate to treat CD70-expressing RCC and highlight the impact of our proprietary Dagger® technology in enabling robust CAR T-cell expansion and persistence in solid tumors.

Response Rates by CD70 Status

Response Rates by CD70 Status CD70+ patients Phase 1b(N=20)

Across the overall Phase 1 TRAVERSE study population, treatment-emergent adverse events were common and primarily hematologic in nature. Adverse events commonly associated with CAR T-cell therapy and lymphodepleting chemotherapy, including infections, CRS, ICANS and hyperinflammatory syndromes such as IEC-HS, were observed. In earlier dose-finding cohorts outside the Phase 1b expansion cohort, fatal treatment-related adverse events were reported, including Grade 5 cardiogenic shock, Grade 5 sepsis and Grade 5 failure to thrive. Following review of these events, the study protocol was amended to incorporate additional diagnostic criteria and management guidance for IEC-HS and enrollment resumed with the regimen subsequently evaluated in the Phase 1b expansion cohort.

The safety profile of ALLO-316 in the Phase 1b cohort was generally consistent with lymphodepletion and an active CAR T product. The most frequent Grade ≥3 events were hematologic and there were no treatment-related Grade 5 events reported in the Phase 1b cohort. The most common all-grade adverse events were cytokine release syndrome (CRS) (68%; with no Grade ≥3 events), neutropenia (68%), decreased white blood cell count (68%), anemia (59%), and thrombocytopenia (55%). Immune effector cell-associated neurotoxicity syndrome (ICANS) occurred in 18% of patients (with no Grade ≥3 events) and no graft-versus-host disease (GvHD) occurred. Improved recognition of immune effector cell-associated hemophagocytic lymphohistiocytosis-like syndrome (IEC-HS) led to diagnosis in 36% of patients, with two patients (9%) experiencing a Grade 3 (one patient) or Grade 4 (one patient) event that subsequently improved with management. No treatment-related Grade 5 events were reported in patients treated in the Phase 1b cohort.

Most Prevalent Treatment-Emergent Adverse Events (TEAEs)

(>20% Any Grade Incidence) and

Adverse Events of Special Interest (AESI)

TEAEs ≥20% incidence in Phase 1b, n (%) Phase 1b (n = 22)†

All Grades Grade ≥3

White blood cell count decreased 15 (68) 15 (68)

ALT increased 7 (32) 2 (9)

Peripheral edema 7 (32) 0

AST increased 6 (27) 2 (9)

AEs of Special Interest Any Grade Grade ≥3

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Graft-versus-host disease 0 0

Clinical Development Plan

The TRAVERSE trial is an open-label, Phase 1, single arm, multicenter clinical trial evaluating the safety and tolerability of ALLO-316 in adult patients with advanced or metastatic ccRCC. Anti-tumor activity, cell kinetics, pharmacodynamics, and correlation of outcome with tumor CD70 expression are evaluated as secondary objectives.

We have developed an investigational in vitro companion diagnostic (IVD) assay designed for use in determining CD70 expression levels for patient selection in TRAVERSE. The trial deployed the IVD assay for the purposes of identifying patients most likely to benefit from ALLO-316.

During the advancement of the TRAVERSE trial with ALLO-316, we have observed allogeneic CAR T cell expansion and persistence driven by CD70 CAR that allows elimination of alloreactive host lymphocytes. This biology has brought the potential for clinical efficacy not often seen in patients with R/R RCC but has also resulted in a hyperinflammatory response in some patients as CD70 CAR T cells expand and persist.

Leveraging recent advances in the management of hyperinflammation following autologous CAR T administration, we have developed a diagnostic and treatment algorithm similar to what our management team previously helped develop for CRS and ICANS associated with autologous CAR T. This algorithm may mitigate the treatment-associated hyperinflammatory response without compromising the CAR T function needed to eradicate solid tumors.

Enrollment in the Phase 1b cohort has been completed and we are now pausing further standard dosing pending durability results for the enrolled patients. We continue to actively explore strategic opportunities, including potential partnerships, to advance this program.

Anti-CD19/CD70 Autoimmune Disease Development Program

Autoimmune disease (AID) can affect organs throughout the body. B cells and T cells are two key components of the immune system, each playing distinct roles in the body’s defense against pathogens and in maintaining immune tolerance. Occasionally, B cells and T cells work together to generate production of pathogenic autoantibodies, which are antibodies that target and react with a person’s own tissues or organs and can contribute to AID. Autoantibodies are critical to the pathogenesis of many AIDs. As a result, we believe that disruption of the B cell-T cell network could lead to an effective treatment of AIDs. As noted above, CD19 is an antigen expressed on the surface of B cells, including pathogenic autoreactive B cells. Activated T cells, which upregulate CD70, may contribute to B-cell autoantibody production and can cause direct tissue damage via an autoreactive T cell receptor. Indeed, CD70 expression has been shown to be elevated on some T cells of patients in certain AIDs, suggesting a pathogenic role for CD70+ T cells in AID. Accordingly, we believe progressing allogeneic CAR T cell therapies directed against CD19 and CD70 could be promising in AID indications.

ALLO-329 is manufactured to express two independent CARs designed to target CD19 and CD70. As illustrated below, a single transgene encoding both the CD19 CAR and the CD70 CAR is targeted for insertion into the TRAC locus using site-specific integration, resulting in uniform expression of both CARs and the lack of TCR expression. ALLO-329 is designed to mediate the depletion of CD19+ B cells and pathogenic T cells that upregulate CD70 expression. CD70 is also upregulated on activated B cells and alloreactive lymphocytes. Therefore, ALLO-329 can also target pathogenic CD70+ B cells and prevent allorejection by eliminating CD70+ alloreactive lymphocytes in the patients. The anti-rejection features of ALLO-329 may help reduce or eliminate the need for lymphodepletion prior to treatment with ALLO-329.

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Lead Target Indications: Systemic Lupus Erythematosus (SLE),

Lupus Nephritis, Idiopathic Inflammatory Myopathies, and Systemic Sclerosis

In January 2025 we announced that the FDA had cleared our IND for a rheumatology basket study of ALLO-329, which we initiated in 2025. Our RESOLUTION trial will evaluate the safety and efficacy of ALLO-329 across multiple autoimmune diseases, including systemic lupus erythematosus (SLE) (including lupus nephritis), idiopathic inflammatory myopathies, and systemic sclerosis. SLE is a chronic, systemic autoimmune disease where the body's immune system mistakenly attacks its own tissues, and is characterized by immune dysregulation, autoantibody production, and inflammation affecting multiple organs. Lupus nephritis (LN) is a serious renal complication of SLE. In LN, the immune system targets the kidneys, leading to inflammation, glomerular damage, and potential renal failure. Idiopathic inflammatory myopathies (IIMs) are a group of rare autoimmune diseases characterized by chronic muscle inflammation and progressive weakness, mainly affecting proximal skeletal muscles. Systemic sclerosis (SSc) is a chronic autoimmune connective tissue disorder characterized by vascular dysfunction, immune dysregulation, and progressive fibrosis affecting the skin and internal organs (lungs, heart, kidneys, and gastrointestinal tract).

Approximately 330,000 cases of SLE (according to Decision Resources Group), 70,000 cases of IIM (according to The Myositis Association), and 100,000 cases of SSc (according to Bergamasco et al, Dove Medical Pres Limited) are estimated to be diagnosed in the United States. These autoimmune diseases generally require targeted immunosuppressive and symptom-specific treatments. SLE is primarily managed with hydroxychloroquine and NSAIDs for mild cases, while severe disease, such as lupus nephritis, necessitates immunosuppressants like mycophenolate mofetil or cyclophosphamide, with biologics such as belimumab and anifrolumab for refractory cases. IIM (including polymyositis and dermatomyositis) is typically treated with high-dose corticosteroids, often combined with methotrexate or azathioprine, while severe or refractory cases may require IVIG or rituximab. SSc management focuses on symptom control, with calcium channel blockers for Raynaud’s phenomenon, mycophenolate mofetil for interstitial lung disease, and vasodilators like sildenafil or bosentan for pulmonary arterial hypertension. Current treatments for SLE, IIM, and SSc have significant limitations, including broad immunosuppression, long-term toxicity, delayed onset of action, disease progression despite therapy, frequent dosing and refractory cases.

Clinical Development Plan

We are developing ALLO-329, an allogeneic CAR T cell product candidate targeting both CD19 and CD70 for the treatment of certain autoimmune diseases. Inclusion of an anti-CD70 CAR in ALLO-329 is designed to reduce or eliminate the need for standard chemotherapy by preventing premature rejection while also targeting CD70+ activated lymphocytes, which may play a direct role in AID pathogenesis. The Phase 1 RESOLUTION trial is a 3+3 dose-escalation study enrolling patients across SLE, IIMs, and SSc. The trial is evaluating up to four dose levels, beginning at 20 million CAR T cells, in two parallel dose escalation pathways: one receiving low-intensity lymphodepletion and one receiving no lymphodepletion. For context, competitive CAR T programs are evaluating dose levels ranging from approximately 150 million cells (autologous) to nearly 1 billion cells (allogeneic) and several utilize multi-drug (eg cyclophosphamide + fludarabine) lymphodepletion.

On April 27, 2025, we announced that ALLO-329 had received three Fast Track Designations (FTD) from the FDA for the treatment of adult patients with SLE, IIM, and SSc. Initial proof-of-concept data from the first patients treated in the first dosing cohorts in both dose escalation pathways are expected in June 2026. The planned data update is expected to include early clinical outcomes and supporting translational data, including disease-related biomarkers, CAR T expansion, and immune reconstitution.

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Future Opportunities

Currently, we remain focused on our three key programs described above. As we advance those programs, we may seek to utilize our allogeneic platform to pursue additional targets of interest, particularly through strategic partnerships. These include the additional targets currently in our pipeline as well as other targets that might be validated in the future, either of which we may seek to combine with our Dagger® technology. For example, we have been developing allogeneic CAR T cell product candidates targeting B-cell maturation antigen (BCMA) for treatment of multiple myeloma (ALLO-715), FLT3 for the treatment of acute myeloid leukemia (ALLO-819), DLL3 for the treatment of small cell lung cancer (ALLO-213), and Claudin 18.2 for the treatment of gastric and pancreatic cancer (ALLO-182).

Our Manufacturing Strategy

We have invested resources to optimize our manufacturing process, including the development of improved analytical methods and instrumentation. We plan to continue to invest in process science, product characterization and manufacturing to continuously improve our manufacturing processes, production and supply chain capabilities over time.

Our product candidates are designed and manufactured via platforms comprised of defined unit operations and technologies. Processes aredeveloped from small to larger scales, incorporating compliant procedures to create cGMP conditions. Although we have a platform-based manufacturing model, each product is unique and for each new product candidate, a developmental phase is necessary to individually customize each engineering step and to create a robust procedure that can later be implemented in a cGMP environment to ensure the production of clinical batches. This work is performed in our process development environment to evaluate and assess variability in each step of the process in order to define the most reliable production conditions.

We are currently utilizing Cell Forge 1 (CF1), our state-of-the-art cell therapy manufacturing facility in Newark, California to manufacture our product candidates. We also utilize separate third-party contractors to manufacture cGMP raw materials that are used for the manufacturing of our product candidates, such as viral vectors that are used to deliver the applicable CAR gene into the T cells. We believe all materials and components utilized in the production of the cell line, viral vector and final T cell product are available from qualified suppliers and suitable for pivotal process development in readiness for registration and commercialization.

Although we are utilizing CF1 for clinical manufacturing, we may continue to rely on CDMOs and other third parties for the manufacturing and processing of our product candidates in the future. We believe the use of contract manufacturing and testing for our first clinical product candidates has allowed us to rapidly prepare for clinical trials in accordance with our development plans. We plan to maintain a robust supply chain with redundant sources of supply comprised of both internal and external infrastructure. We expect CF1 and third-party manufacturers will be capable of providing and processing sufficient quantities of our product candidates to meet anticipated clinical trial demands.

Strategic Agreements

Allogene Overland Biopharm (CY) Limited (Allogene Overland), later renamed Overland Therapeutics Inc. (Overland Therapeutics), was initially established as a joint venture by us and Overland Pharmaceuticals (CY) Inc. (Overland) pursuant to a Share Purchase Agreement (Share Purchase Agreement), dated December 14, 2020. Concurrently, on December 14, 2020, we entered into a License Agreement (License Agreement) with Allogene Overland for the purpose of developing, manufacturing and commercializing certain allogeneic CAR T cell therapies (JV Licensed Products) for patients in greater China, Taiwan, South Korea and Singapore (the JV Territory).

On May 24, 2024, we, Overland, and Allogene Overland entered into a Share Exchange Agreement (Share Exchange Agreement) pursuant to which Overland’s cell therapy business merged into Allogene Overland (the Organizational Restructuring). Under a separate agreement between Overland and HH BioPharma Holdings Ltd. (HBP) executed on May 24, 2024, Overland distributed all Series Seed Preferred Shares of Allogene Overland held by Overland to HBP and HBP has assumed all rights and obligations attached to such shares and all rights and obligations of Overland under the Share Exchange Agreement. In connection with the Organizational Restructuring, on May 24, 2024, we and Allogene Overland PRC, entered into a First Amendment to the License Agreement (the License Amendment) to amend and supplement certain provisions of the License Agreement. Under the License Amendment, we continue to grant Allogene Overland PRC an exclusive license to develop, manufacture, and commercialize the JV Licensed Products in the JV Territory, with us retaining exclusive rights to the JV Licensed Products outside the JV Territory

We have also entered into multiple additional strategic agreements and collaborations, including an Asset Contribution Agreement with Pfizer (the Pfizer Agreement), a License Agreement with Cellectis (the Cellectis Agreement), the Servier

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Agreement, a Collaboration and License Agreement (the Notch Agreement) with Notch Therapeutics Inc. (Notch), and a Strategic Collaboration Agreement with Foresight Diagnostics.

For additional information regarding our significant agreements refer to Note 6 in our consolidated financial statements appearing elsewhere in this Annual Report.

Intellectual Property

Our commercial success depends in part on our ability to obtain and maintain proprietary protection for our product candidates, as well as novel discoveries, product development technologies, and know-how. Our commercial success also depends in part on our ability to operate without infringing on the proprietary rights of others and to prevent others from infringing our proprietary rights. Our policy is to develop and maintain protection of our proprietary position by, among other methods, filing or in-licensing U.S. and foreign patents and applications related to our technology, inventions, and improvements that are important to the development and implementation of our business.

We also rely on trademarks, trade secrets, know-how, continuing technological innovation, confidentiality agreements, and invention assignment agreements to develop and maintain our proprietary position. The confidentiality agreements are designed to protect our proprietary information and the invention assignment agreements are designed to grant us ownership of technologies that are developed for us by our employees, consultants, or other third parties. We seek to preserve the integrity and confidentiality of our data and trade secrets by maintaining physical security of our premises and physical and electronic security of our information technology systems. While we have confidence in our agreements and security measures, either may be breached, and we may not have adequate remedies. In addition, our trade secrets may otherwise become known or independently discovered by competitors.

With respect to both licensed and company-owned intellectual property, we cannot be sure that patents will be granted with respect to any of our pending patent applications or with respect to any patent applications filed by us in the future, nor can we be sure that any of our existing patents or any patents that may be granted to us in the future will be commercially useful in protecting our commercial products and methods of using and manufacturing the same.

We are actively building our intellectual property portfolio around our product candidates and our discovery programs, based on our own intellectual property as well as licensed intellectual property. Following the execution of the Pfizer Agreement, we are the owner of, co-owner of, or the licensee of multiple patents and patent applications in the United States and worldwide. These licensed assets include rights to the Cellectis TALEN® gene-editing technology to engineer T cells that lack functional TCRs and to inactivate the CD52 gene in donor cells. We have exclusive worldwide rights to these patents for certain antigen targets, including BCMA, CD70, FLT3, DLL3 and Claudin 18.2, and have U.S., EU, and UK rights to these patents for cema-cel. We also have rights to Cellectis intellectual property for technology covering an engineered T cell therapy combining CD52 gene knockout in combination with an anti-CD52 antibody for certain products directed against certain antigen targets. For our lead programs, our patent rights are generally composed of patents and pending patent applications that are solely owned by us, co-owned with Servier, co-owned with Cellectis, co-owned with Pfizer, exclusively licensed from Pfizer, exclusively licensed from Servier, or exclusively licensed from Cellectis.

Our patent portfolio includes protection for our clinical-stage product candidates, ALLO-501, cema-cel, ALLO-316, ALLO-329, ALLO-715, and ALLO-605, as well as our research-stage candidates. With respect to cema-cel, we have an exclusive license from Servier to patent rights in the United States covering compositions of matter of and methods of making and using cema-cel. With respect to ALLO-715, ALLO-605 and ALLO-316, we have an exclusive license from Pfizer to patent rights covering ALLO-715, ALLO-605, and ALLO-316 in the United States and in foreign jurisdictions. These rights cover compositions of matter of and methods of making and using ALLO-715, ALLO-605 and ALLO-316. We also have patent rights to the TurboCARTM and Dagger® technologies solely owned by us, including technology that covers the TurboCARTM construct that is part of ALLO-605, and the Dagger® construct that is part of ALLO-329. More generally, our patent portfolio and filing strategy is designed to provide multiple layers of protection by pursuing claims directed toward, for example: (1) antigen binding domains directed to the targets of our product candidates; (2) CAR constructs used in our product candidates; (3) methods of treatment for therapeutic indications; (4) manufacturing processes, preconditioning methods, and dosing regimens; and (5) immune evasion and other gene and cell engineering technology.

The term of individual patents depends upon the legal term of the patents in the countries in which they are obtained. In most countries in which we file, the patent term, generally, is 20 years from the date of filing of the first non-provisional application to which priority is claimed. In the United States, patent term may be lengthened by patent term adjustment, which compensates a patentee for administrative delays by the United States Patent and Trademark Office in granting a patent, or may be shortened if a patent is terminally disclaimed over an earlier-filed patent. In the United States, the term of a patent that covers an FDA-approved drug may also be eligible for a patent term extension of up to five years under the Hatch-Waxman Act, which is designed to compensate for the patent term lost during the FDA regulatory review process. The length of the patent term extension involves a complex calculation based on the length of time it takes for regulatory review. A patent term extension under the Hatch-Waxman Act cannot extend the remaining term of a patent beyond a total of 14 years from the date

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of product approval and only one patent applicable to an approved drug may be extended. Moreover, a patent can only be extended once, and thus, if a single patent is applicable to multiple products, it can only be extended based on one product. Similar provisions are available in Europe and certain other foreign jurisdictions to extend the term of a patent that covers an approved drug.

Competition

Oncology is a highly competitive market for drug development. If successfully developed, our products will compete with therapies that have been developed or are in development at biopharmaceutical companies, academic research institutions, governmental agencies and public and private research institutions. We anticipate increasing competition from existing and new cell-based therapies, including products that are both autologous and allogeneic in nature. We also anticipate competition from other therapeutic modalities, including antibodies, bispecific T cell engagers, antibody drug conjugates, and small molecule therapeutics. In particular, the rapid development and commercialization of bispecific antibodies and other “off-the-shelf” immune oncology products may reduce the number of patients eligible for, or willing to receive, cell therapy, may shift treatment sequencing and standards of care, and may intensify pricing and reimbursement pressures, any of which could adversely affect enrollment in our clinical trials and, if approved, the commercial adoption of our product candidates.

Autologous T cell therapies directed at CD19 have been commercialized by Novartis, Kite/Gilead and Bristol-Myers Squibb Company (BMS) and are witnessing increased adoption in the marketplace. In August 2017, Novartis obtained FDA approval to commercialize Kymriah® for the treatment of children and young adults with B-cell ALL that is refractory or has relapsed at least twice. In May 2018, Kymriah® received FDA approval for adults with certain types of LBCL who have not responded to, or who have relapsed after, at least two other types of systemic treatment (3rd-line LBCL), and in May 2022, Kymriah® received FDA approval for the treatment of adult patients with relapsed or refractory follicular lymphoma (FL) after two or more lines of systemic therapy. In October 2017, Kite/Gilead obtained FDA approval to commercialize Yescarta®, for the treatment of adult patients with 3rd-line LBCL. This was followed by approval of Yescarta® for R/R FL in March 2021 and approval of 2nd-line LBCL in April 2022. Kite has also received FDA approval for a second autologous CD19-directed T cell therapy, Tecartus®, for use in patients with R/R mantle cell lymphoma and adult patients with R/R B-cell ALL. In February 2021, BMS obtained FDA approval for its anti-CD19 autologous T cell therapy, Breyanzi® for the treatment of adults with 3rd-line LBCL. The Breyanzi® label was extended to 2nd-line LBCL in June 2022, R/R Chronic Lymphocytic Leukemia (CLL) in March 2024, R/R FL in May 2024, and R/R Mantle Cell Lymphoma (MCL) in May 2024. In November 2024, Autolus Therapeutics obtained FDA approval for its anti-CD19 autologous T cell therapy, Aucatzyl® (obecabtagene autoleucel), for adults with relapsed or refractory B-cell precursor ALL.

Autologous cell therapies directed at BCMA have been commercialized by BMS and Janssen, a Johnson & Johnson company. In March 2021, BMS and partner 2seventy bio, Inc. received FDA approval of Abecma®, an anti-BCMA autologous T cell therapy, for the treatment of adult patients with multiple myeloma who have received at least four prior therapies. Janssen and partner Legend Bio received approval for Carvykti®, an anti-BCMA autologous T cell therapy, for the same indication in February 2022. Both Abecma® and Carvykti® have succeeded in pivotal trials in earlier lines of R/R myeloma and have gained label extensions into this market in 2024.

Autologous T cell therapies are being developed by a number of additional companies, including but not limited to 2seventy bio, Inc., Adaptimmune Therapeutics PLC, Alaunos Therapeutics, Inc., Arcellx, Inc., Arsenal Biosciences, Inc., AstraZeneca plc, Autolus Therapeutics plc, Eureka Therapeutics, Inc., Galapagos NV, Gilead Sciences, Inc., Instil Bio, Inc., Iovance Biotherapeutics, Inc., Legend Biotech Corp., Lyell Immunopharma Inc., Mustang Bio, Inc., Triumvira Immunologics, and TScan Therapeutics, Inc.

Autologous CAR T therapy has made significant advances in addressing R/R NHL, and has moved to earlier lines of therapy, as further described above. We do not, however, believe that autologous CAR T therapy will be a viable option in the 1L consolidation setting because of the reduced T cell counts in patients who have recently completed 1L therapy as well as lengthy lead time for the individualized manufacturing process for autologous CAR T. Once it is determined that a patient is MRD positive following standard 1L treatment, we believe that the speed at which a patient is treated with CAR T therapy will enhance response rates. Published results of front-line chemotherapy outcomes suggest that MRD positive patients are likely to progress, and some patients may do so very quickly (i.e., within a matter of weeks after completing 1L therapy). Furthermore, data suggests that patients who have low burden of disease when they receive CAR T cells tend to have better safety and efficacy outcomes, including lower rates of CRS and more durable remissions. As a result, we believe that it will be important that patients receive CAR T therapy as soon as possible following an MRD positive diagnosis, which will not allow for the lengthy manufacturing process of autologous CAR T.

In addition, a number of companies are developing in vivo approaches intended to generate CAR T cells inside the patient by delivering genetic payloads (for example, mRNA encoding a CAR) to immune cells using delivery systems such as targeted lipid nanoparticles, with the goal of avoiding ex vivo cell collection and individualized manufacturing. These

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approaches are early-stage and face significant development challenges (including targeted delivery, control of CAR expression and persistence, safety, and scalability of delivery platforms), but if successful, they could broaden use of CAR T therapy in both oncology and autoimmune disease and therefore may compete with our programs.

Allogeneic T cell products have yet to receive FDA approval though the number of companies developing allogeneic product candidates is substantial. These include AstraZeneca, plc, Atara Biotherapeutics, Inc., Beam Therapeutics, Inc., Caribou Biosciences, Inc., CRISPR Therapeutics AG, Editas Medicine, Inc., F. Hoffmann-La Roche AG, Fate Therapeutics, Inc., Gilead Sciences, Inc., Imugene Ltd., Intellia Therapeutics, Inc., Legend Biotech Corp., Precision Biosciences, Inc., and Sana Biotechnology, Inc. Some of the allogeneic T cell candidates under development target the same antigens that are part of our clinical pipeline, such as CD19, BCMA and CD70. Additionally, Cellectis has several fully-owned allogeneic CAR T programs that could compete with programs that fall outside our agreement with Cellectis.

There are also cell therapies under development that are based upon cell types other than the common type of T cells used by us and known as alpha/beta T cells. These include product candidates derived from natural killer cells, natural killer T cells, gamma/delta T cells and macrophage cells. Companies developing such therapies include Adicet Bio, Inc., Artiva Biotherapeutics, Inc., Carisma Therapeutics, Inc., Cytovia Therapeutics, Inc., Celularity, Inc., Century Therapeutics, Inc., Fate Therapeutics, Inc., Gamida Cell Ltd., In8bio, Inc., Lyell Immunopharma, Inc., Nkarta, Inc., Shoreline Bio, Inc., and Takeda Pharmaceutical Company Limited.

Competition may also arise from non-cell based immune oncology platforms. For instance, we may experience competition from companies, such as AbbVie, Inc., Amgen Inc., BMS, Compass Therapeutics, Inc., F. Hoffmann-La Roche AG, Genmab A/S, GlaxoSmithKline plc, Immunocore Holdings plc, Johnson & Johnson, MacroGenics, Inc., Merck & Co. Inc., Merus N.V., Pfizer, Regeneron Pharmaceuticals, Inc., and Xencor Inc., that are pursuing bispecific T cell engagers that target both the cancer antigen and T cell receptor, thus bringing both cancer cells and T cells in close proximity to maximize the likelihood of an immune response to the cancer cells. Bi-specific T cell engagers targeting BCMA for myeloma and CD20 for lymphoma have advanced rapidly in development, with initial FDA approvals beginning in 2022, and additional products approved since that time. These therapies may be administered without individualized cell collection and manufacturing, and in some settings may be used before, after, or instead of cell therapies. As a result, bispecific therapies may reduce the addressable patient population for our product candidates, compete for physician and patient preference based on convenience or risk-benefit profile, and contribute to increased pricing and reimbursement pressure. Additionally, companies, such as ADC Therapeutics SA, Amgen Inc., Daiichi Sankyo Company, Limited, Gilead Sciences, Inc., GlaxoSmithKline plc, ImmunoGen, Inc., Pfizer Inc., Regeneron Pharmaceuticals, Inc., and Sutro Biopharma, Inc. are pursuing antibody drug conjugates, which utilize the targeting ability of antibodies to deliver cell-killing agents directly to cancer cells.

In addition to the significant competition noted above in oncology markets, as early data in the use of CAR T cell therapy for the treatment of autoimmune disease has been emerging since 2022, there have been many companies initiating autologous and/or allogeneic cell therapy development programs that would be in direct competition to our autoimmune program.For example, we may experience competition in these markets from companies such as Adicet Bio, Inc., Arcellx, Inc., Atara Biotherapeutics, Inc., Autolus Therapeutics plc, BMS, Cabaletta Bio, Inc., Caribou Biosciences, Inc., Cartesian Therapeutics, Inc., CRISPR Therapeutics AG, Fate Therapeutics, Inc., Gracell Biotechnologies, Inc., ImmPACT Bio USA, Inc., Kyverna Therapeutics, Inc., Nkarta, Inc., Novartis, Sana Biotechnology, Inc., and TG Therapeutics Inc.

Many of our competitors, either alone or with their collaboration partners, have significantly greater financial resources and expertise in research and development, pre-clinical testing, clinical trials, manufacturing, and marketing than we do. Future collaborations and mergers and acquisitions may result in further resource concentration among a smaller number of competitors.

Our commercial potential could be reduced or eliminated if our competitors develop and commercialize products that are better tolerated, more effective, have fewer or less severe side effects, are more convenient or are less expensive than products that we may develop. Our competitors also may obtain FDA or other regulatory approval for their products more rapidly than we may obtain approval for ours, which could result in our competitors establishing a strong market position before we are able to enter the market or make our development more complicated. The key competitive factors affecting the success of all of our programs are likely to be efficacy, safety, convenience, and cost of manufacturing.

These competitors may also vie for a similar pool of qualified scientific and management talent, sites and patient populations for clinical trials, and investor capital, as well as for technologies complementary to, or necessary for, our programs.

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Government Regulation and Product Approval

As a biopharmaceutical company that operates in the United States, we are subject to extensive regulation. Our cell products will be regulated as biologics. With this classification, commercial production of our products will need to occur in registered facilities in compliance with cGMP for biologics. The FDA categorizes human cell- or tissue-based products as either minimally manipulated or more than minimally manipulated, and has determined that more than minimally manipulated products require clinical trials to demonstrate product safety and efficacy and the submission of a biologics license application (BLA) for marketing authorization. Our products are considered more than minimally manipulated and will require evaluation in clinical trials and the submission and approval of a BLA before we can market them.

Government authorities in the United States (at the federal, state and local level) and in other countries extensively regulate, among other things, the research, development, testing, manufacturing, quality control, approval, labeling, packaging, storage, record-keeping, promotion, advertising, distribution, post-approval monitoring and reporting, marketing and export and import of biopharmaceutical products such as those we are developing. Our product candidates must be approved by the FDA before they may be legally marketed in the United States and by the appropriate foreign regulatory agency before they may be legally marketed in foreign countries. Generally, our activities in other countries will be subject to regulation that is similar in nature and scope as that imposed in the United States, although there can be important differences. Additionally, some significant aspects of regulation in Europe are addressed in a centralized way, but country-specific regulation remains essential in many respects. The process for obtaining regulatory marketing approvals and the subsequent compliance with appropriate federal, state, local and foreign statutes and regulations require the expenditure of substantial time and financial resources.

U.S. Product Development Process

In the United States, the FDA regulates pharmaceutical and biological products under the Federal Food, Drug and Cosmetic Act (FDCA), the Public Health Service Act (PHSA) and their implementing regulations. The process of obtaining regulatory approvals and the subsequent compliance with appropriate federal, state, local and foreign statutes and regulations require the expenditure of substantial time and financial resources. Failure to comply with the applicable U.S. requirements at any time during the product development process, approval process or after approval, may subject an applicant to administrative or judicial sanctions. FDA sanctions could include, among other actions, refusal to approve pending applications, withdrawal of an approval, a clinical hold, warning letters, product recalls or withdrawals from the market, product seizures, total or partial suspension of production or distribution injunctions, fines, refusals of government contracts, restitution, disgorgement or civil or criminal penalties. We have been placed on clinical hold previously and any future agency or judicial enforcement action could have a material adverse effect on us. The process required by the FDA before a biological product may be marketed in the United States generally involves the following:

•completion of nonclinical laboratory tests and animal studies according to good laboratory practices (GLPs) and applicable requirements for the humane use of laboratory animals or other applicable regulations;

•submission to the FDA of an IND, which must become effective before human clinical trials may begin;

•approval by an independent Institutional Review Board (IRB) or ethics committee at each clinical site before the trial is commenced;

•performance of adequate and well-controlled human clinical trials according to the FDA’s regulations commonly referred to as good clinical practices (GCPs) and any additional requirements for the protection of human research patients and their health information, to establish the safety and efficacy of the proposed biological product for its intended use;

•submission to the FDA of a BLA for marketing approval that includes substantial evidence of safety, purity, and potency from results of nonclinical testing and clinical trials, and which is validated as complete for review by the FDA;

•satisfactory completion of an FDA Advisory Committee review, if applicable;

•satisfactory completion of an FDA inspection of the manufacturing facility or facilities where the biological product is produced to assess compliance with cGMP, to assure that the facilities, methods and controls are adequate to preserve the biological product’s identity, strength, quality and purity and, if applicable, the FDA’s current good tissue practices (GTPs) for the use of human cellular and tissue products;

•potential FDA audit of the nonclinical study and clinical trial sites that generated the data in support of the BLA; and

•FDA review and approval, or licensure, of the BLA.

Before testing any biological product candidate, including our product candidates, in humans, the product candidate enters the preclinical testing stage. Preclinical tests, also referred to as nonclinical studies, include laboratory evaluations of

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product chemistry, toxicity and formulation, as well as animal studies to assess the potential safety and activity of the product candidate. The conduct of the preclinical tests must comply with federal regulations and requirements including GLPs. The clinical trial sponsor must submit the results of the preclinical tests, together with manufacturing information, analytical data, any available clinical data or literature and a proposed clinical protocol, to the FDA as part of the IND. Some preclinical testing may continue even after the IND is submitted. The IND automatically becomes effective 30 days after receipt by the FDA, unless the FDA raises concerns or questions regarding the proposed clinical trials and places the trial on a clinical hold within that 30-day time period. In such a case, the IND sponsor and the FDA must resolve any outstanding concerns before the clinical trial can begin. The FDA may also impose clinical holds on a biological product candidate at any time before or during clinical trials due to safety concerns or non-compliance. If the FDA imposes a clinical hold, trials may not recommence without FDA authorization and then only under terms authorized by the FDA. Accordingly, we cannot be sure that submission of an IND will result in the FDA allowing clinical trials to begin, or that, once begun, issues will not arise that suspend or terminate such trials.

Clinical trials involve the administration of the biological product candidate to patients under the supervision of qualified investigators, generally physicians not employed by or under the trial sponsor’s control. Clinical trials are conducted under protocols detailing, among other things, the objectives of the clinical trial, dosing procedures, subject selection and exclusion criteria, and the parameters to be used to monitor subject safety, including stopping rules that assure a clinical trial will be stopped if certain adverse events should occur. Each protocol and any amendments to the protocol must be submitted to the FDA as part of the IND. Clinical trials must be conducted and monitored in accordance with the FDA’s regulations comprising the GCP requirements, including the requirement that all research patients provide informed consent. Further, each clinical trial must be reviewed and approved by an independent IRB at or servicing each institution at which the clinical trial will be conducted. An IRB is charged with protecting the welfare and rights of trial participants and considers such items as whether the risks to individuals participating in the clinical trials are minimized and are reasonable in relation to anticipated benefits. The IRB also approves the form and content of the informed consent that must be signed by each clinical trial subject or his or her legal representative and must monitor the clinical trial until completed. Certain clinical trials involving human gene transfer research also must be overseen by an Institutional Biosafety Committee (IBC), a standing committee to provide peer review of the safety of research plans, procedures, personnel training and environmental risks of work involving recombinant DNA molecules. IBCs are typically assigned certain review responsibilities relating to the use of recombinant DNA molecules, including reviewing potential environmental risks, assessing containment levels, and evaluating the adequacy of facilities, personnel training, and compliance with the National Institutes of Health Guidelines. We may also engage an independent group of qualified experts organized by the clinical study sponsor, known as a data safety monitoring board, to provide authorization for whether or not a study may move forward at designated check points based on access to certain data from the study and may halt the clinical trial if it determines that there is an unacceptable safety risk for subjects or other grounds, such as no demonstration of efficacy. There are also requirements governing the reporting of ongoing clinical studies and clinical study results to public registries.

Human clinical trials are typically conducted in three sequential phases that may overlap or be combined:

•Phase 1. The biological product is initially introduced into healthy human subjects and tested for safety. In the case of some products for severe or life-threatening diseases, especially when the product may be too inherently toxic to ethically administer to healthy volunteers, the initial human testing is often conducted in patients.

•Phase 2. The biological product is evaluated in a limited patient population to identify possible adverse effects and safety risks, to preliminarily evaluate the efficacy of the product for specific targeted diseases and to determine dosage tolerance, optimal dosage and dosing schedule.

•Phase 3. Clinical trials are undertaken to further evaluate dosage, clinical efficacy, potency, and safety in an expanded patient population at geographically dispersed clinical trial sites. These clinical trials are intended to establish the overall risk to benefit ratio of the product and provide an adequate basis for product labeling.

Long term follow-up for all patients who get marketed product and post-approval clinical trials, sometimes referred to as Phase 4 clinical trials, may be required after initial marketing approval. These clinical trials are used to gain additional experience from the treatment of patients in the intended therapeutic indication, particularly for long-term safety follow-up. During all phases of clinical development, regulatory agencies require extensive monitoring and auditing of all clinical activities, clinical data, and clinical trial investigators. Annual progress reports detailing the results of the clinical trials must be submitted to the FDA. Written IND safety reports must be promptly submitted to the FDA, and the investigators for serious and unexpected adverse events, any findings from other studies, tests in laboratory animals or in vitro testing that suggest a significant risk for human patients, or any clinically important increase in the rate of a serious suspected adverse reaction over that listed in the protocol or investigator brochure. The sponsor must submit an IND safety report within 15 calendar days after the sponsor determines that the information qualifies for reporting. The sponsor also must notify the FDA of any unexpected fatal or life-threatening suspected adverse reaction within seven calendar days after the sponsor’s initial receipt of the information. Phase 1, Phase 2 and Phase 3 clinical trials may not be completed successfully within any specified period, if at all. The FDA or the sponsor or its data safety monitoring board may suspend or terminate a clinical trial at any time on various

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grounds, including a finding that the research patients are being exposed to an unacceptable health risk, including risks inferred from other unrelated immunotherapy trials. Similarly, an IRB can suspend or terminate approval of a clinical trial at its institution if the clinical trial is not being conducted in accordance with the IRB’s requirements or if the biological product has been associated with unexpected serious harm to patients.

Concurrently with clinical trials, companies usually complete additional studies and must also develop additional information about the physical characteristics of the biological product as well as finalize a process for manufacturing the product in commercial quantities in accordance with cGMP requirements. To help reduce the risk of the introduction of adventitious agents with use of biological products, the PHSA emphasizes the importance of manufacturing control for products whose attributes cannot be precisely defined. The manufacturing process must be capable of consistently producing quality batches of the product candidate and, among other things, the sponsor must develop methods for testing the identity, strength, quality, potency and purity of the final biological product. Additionally, appropriate packaging must be selected and tested and stability studies must be conducted to demonstrate that the biological product candidate does not undergo unacceptable deterioration over its shelf life.

The FDA has continued to issue guidance specific to cellular and gene therapy (CGT) products. For example, in November 2024, the FDA issued draft guidance providing frequently asked questions on CGT product development, including common regulatory, chemistry, manufacturing and controls (CMC), and clinical issues, and in December 2023, the FDA issued draft guidance on potency assurance for CGT products that discusses a science- and risk-based strategy to help assure potency across the product lifecycle.

U.S. Review and Approval Processes

After the completion of clinical trials of a biological product, FDA approval of a BLA must be obtained before commercial marketing of the biological product. The BLA submission must include results of product development, laboratory and animal studies, human trials, information on the manufacture and composition of the product, proposed labeling and other relevant information. The testing and approval processes require substantial time and effort and there can be no assurance that the FDA will accept the BLA for filing and, even if filed, that any approval will be granted on a timely basis, if at all.

Under the Prescription Drug User Fee Act (PDUFA), as amended, each BLA must be accompanied by a significant user fee. The FDA adjusts the PDUFA user fees on an annual basis. PDUFA also imposes an annual program fee for biological products. Fee waivers or reductions are available in certain circumstances, including a waiver of the application fee for the first application filed by a small business. Additionally, no user fees are assessed on BLAs for products designated as orphan drugs, unless the product also includes a non-orphan indication.

Within 60 or 74 days following submission of the application, the FDA reviews a BLA submitted to determine if it is substantially complete before the agency accepts it for filing. The FDA may refuse to file any BLA that it deems incomplete or not properly reviewable at the time of submission and may request additional information. In this event, the BLA must be resubmitted with the additional information. The resubmitted application also is subject to review before the FDA accepts it for filing. Once the submission is accepted for filing, the FDA begins an in-depth substantive review of the BLA. The FDA reviews the BLA to determine, among other things, whether the proposed product is safe, potent, and/or effective for its intended use, and has an acceptable purity profile, and whether the product is being manufactured in accordance with cGMP to assure and preserve the product’s identity, safety, strength, quality, potency and purity. The FDA may refer applications for novel biological products or biological products that present difficult questions of safety or efficacy to an advisory committee, typically a panel that includes clinicians and other experts, for review, evaluation and a recommendation as to whether the application should be approved and under what conditions. The FDA is not bound by the recommendations of an advisory committee, but it considers such recommendations carefully when making decisions. During the biological product approval process, the FDA also will determine whether a Risk Evaluation and Mitigation Strategy (REMS) is necessary to assure the safe use of the biological product. A REMS is a safety strategy to manage a known or potential serious risk associated with a medicine and to enable patients to have continued access to such medicines by managing their safe use, and could include medication guides, physician communication plans, or elements to assure safe use, such as restricted distribution methods, patient registries and other risk minimization tools. If the FDA concludes a REMS is needed, the sponsor of the BLA must submit a proposed REMS. The FDA will not approve a BLA without a REMS, if required.

Before approving a BLA, the FDA will inspect the facilities at which the product is manufactured. The FDA will not approve the product unless it determines that the manufacturing processes and facilities are in compliance with cGMP requirements and adequate to assure consistent production of the product within required specifications. For immunotherapy products, the FDA also will not approve the product if the manufacturer is not in compliance with the GTPs, to the extent applicable. These are FDA regulations and guidance documents that govern the methods used in, and the facilities and controls used for, the manufacture of human cells, tissue, and cellular and tissue-based products (HCT/Ps), which are human cells or tissue intended for implantation, transplant, infusion, or transfer into a human recipient. The primary intent of the GTP requirements is to ensure that cell and tissue-based products are manufactured in a manner designed to prevent the introduction,

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transmission and spread of communicable disease. FDA regulations also require tissue establishments to register and list their HCT/Ps with the FDA and, when applicable, to evaluate donors through screening and testing. Additionally, before approving a BLA, the FDA will typically inspect one or more clinical sites to assure that the clinical trials were conducted in compliance with IND trial requirements and GCP requirements. To assure cGMP, GTP and GCP compliance, an applicant must incur significant expenditure of time, money and effort in the areas of training, record keeping, production, and quality control.

Notwithstanding the submission of relevant data and information, the FDA may ultimately decide that the BLA does not satisfy its regulatory criteria for approval and deny approval. Data obtained from clinical trials are not always conclusive and the FDA may interpret data differently than we interpret the same data. If the agency decides not to approve the BLA in its present form, the FDA will issue a complete response letter that describes all of the specific deficiencies in the BLA identified by the FDA. The deficiencies identified may be minor, for example, requiring labeling changes, or major, for example, requiring additional clinical trials. Additionally, the complete response letter may include recommended actions that the applicant might take to place the application in a condition for approval. If a complete response letter is issued, the applicant may either resubmit the BLA, addressing all of the deficiencies identified in the letter, or withdraw the application.

If a product receives regulatory approval, the approval may be limited to specific diseases and dosages or the indications for use may otherwise be limited, which could restrict the commercial value of the product. Further, the FDA may require that certain contraindications, warnings or precautions be included in the product labeling. The FDA may impose restrictions and conditions on product distribution, prescribing, or dispensing in the form of a risk management plan, or otherwise limit the scope of any approval. In addition, the FDA may require post marketing clinical trials, sometimes referred to as Phase 4 clinical trials, designed to further assess a biological product’s safety and effectiveness, and testing and surveillance programs to monitor the safety of approved products that have been commercialized.

In addition, under the Pediatric Research Equity Act (PREA), a BLA or supplement to a BLA must contain data to assess the safety and effectiveness of the product for the claimed indications in all relevant pediatric subpopulations and to support dosing and administration for each pediatric subpopulation for which the product is safe and effective. The FDA may grant deferrals for submission of data or full or partial waivers.

Orphan Drug Designation

Under the Orphan Drug Act, the FDA may grant orphan designation to a drug or biologic intended to treat a rare disease or condition, which is generally a disease or condition that affects fewer than 200,000 individuals in the United States, or more than 200,000 individuals in the United States and for which there is no reasonable expectation that the cost of developing and making available in the United States a drug or biologic for this type of disease or condition will be recovered from sales in the United States for that drug or biologic. Orphan drug designation must be requested before submitting a BLA. After the FDA grants orphan drug designation, the generic identity of the therapeutic agent and its potential orphan use are disclosed publicly by the FDA. The orphan drug designation does not convey any advantage in, or shorten the duration of, the regulatory review or approval process.

If a product that has orphan drug designation subsequently receives the first FDA approval for the disease for which it has such designation, the product is entitled to orphan product exclusivity, which means that the FDA may not approve any other applications, including a full BLA, to market the same biologic for the same indication for seven years, except in limited circumstances, such as a showing of clinical superiority to the product with orphan drug exclusivity. Orphan drug exclusivity does not prevent FDA from approving a different drug or biologic for the same disease or condition, or the same drug or biologic for a different disease or condition. Among the other benefits of orphan drug designation are tax credits for certain research and a waiver of the BLA application user fee.

A designated orphan drug may not receive orphan drug exclusivity if it is approved for a use that is broader than the indication for which it received orphan designation. In addition, exclusive marketing rights in the United States may be lost if the FDA later determines that the request for designation was materially defective or if the manufacturer is unable to assure sufficient quantities of the product to meet the needs of patients with the rare disease or condition.

Expedited Development and Review Programs

The FDA has a fast track program that is intended to expedite or facilitate the process for reviewing new products that meet certain criteria. Specifically, new products are eligible for fast track designation if they are intended to treat a serious or life-threatening disease or condition and demonstrate the potential to address unmet medical needs for the disease or condition. Fast track designation applies to the combination of the product and the specific indication for which it is being studied. Unique to a fast track product, the FDA may consider for review sections of the BLA on a rolling basis before the complete application is submitted, if the sponsor provides a schedule for the submission of the sections of the BLA, the FDA agrees to accept sections of the BLA and determines that the schedule is acceptable, and the sponsor pays any required user fees upon submission of the first section of the BLA.

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Any product submitted to the FDA for approval, including a product with a fast track designation, may also be eligible for other types of FDA programs intended to expedite development and review, such as priority review and accelerated approval. A product is eligible for priority review if it has the potential to provide safe and effective therapy where no satisfactory alternative therapy exists or a significant improvement in the treatment, diagnosis or prevention of a disease compared to marketed products. The FDA will attempt to direct additional resources to the evaluation of an application for a new product designated for priority review in an effort to facilitate the review. Additionally, a product may be eligible for accelerated approval. Products studied for their safety and effectiveness in treating serious or life-threatening diseases or conditions may receive accelerated approval upon a determination that the product has an effect on a surrogate endpoint that is reasonably likely to predict clinical benefit, or on a clinical endpoint that can be measured earlier than irreversible morbidity or mortality, that is reasonably likely to predict an effect on irreversible morbidity or mortality or other clinical benefit, taking into account the severity, rarity, or prevalence of the condition and the availability or lack of alternative treatments. As a condition of approval, the FDA may require that a sponsor of a drug or biological product receiving accelerated approval perform adequate and well-controlled post-marketing clinical studies. In addition, the FDA currently requires as a condition for accelerated approval pre-approval of promotional materials, which could adversely impact the timing of the commercial launch of the product.

Congress expanded FDA’s authorities regarding accelerated approval in 2023, including authority to require that confirmatory trials be underway prior to approval or within a specified time period after approval, and the FDA issued draft guidance in January 2025 describing factors it intends to consider when determining whether a confirmatory trial is “underway.”

Regenerative Medicine Advanced Therapy (RMAT) designation was established by FDA to facilitate an efficient development program for, and expedite review of, any drug that meets the following criteria: (1) it qualifies as a RMAT, which is defined as a cell therapy, therapeutic tissue engineering product, human cell and tissue product, or any combination product using such therapies or products, with limited exceptions; (2) it is intended to treat, modify, reverse, or cure a serious or life-threatening disease or condition; and (3) preliminary clinical evidence indicates that the drug has the potential to address unmet medical needs for such a disease or condition. RMAT designation provides potential benefits that include more frequent meetings with FDA to discuss the development plan for the product candidate and eligibility for rolling review and priority review. Products granted RMAT designation may also be eligible for accelerated approval on the basis of a surrogate or intermediate endpoint reasonably likely to predict long-term clinical benefit, or reliance upon data obtained from a meaningful number of sites, including through expansion to additional sites. Once approved, when appropriate, the FDA can permit fulfillment of post-approval requirements under accelerated approval through the submission of clinical evidence, clinical studies, patient registries, or other sources of real world evidence such as electronic health records; through the collection of larger confirmatory datasets; or through post-approval monitoring of all patients treated with the therapy prior to approval.

Breakthrough therapy designation is also intended to expedite the development and review of products that treat serious or life-threatening conditions. The designation by FDA requires preliminary clinical evidence that a product candidate, alone or in combination with other drugs and biologics, demonstrates substantial improvement over currently available therapy on one or more clinically significant endpoints, such as substantial treatment effects observed early in clinical development. Breakthrough therapy designation comes with all of the benefits of fast track designation, which means that the sponsor may file sections of the BLA for review on a rolling basis if certain conditions are satisfied, including an agreement with FDA on the proposed schedule for submission of portions of the application and the payment of applicable user fees before the FDA may initiate a review.

Fast track designation, priority review, RMAT and Breakthrough therapy designation do not change the standards for approval but may expedite the development or approval process.

Post-Approval Requirements

Any products for which we receive FDA approvals are subject to continuing regulation by the FDA, including, among other things, record-keeping requirements, reporting of adverse experiences with the product, providing the FDA with updated safety and efficacy information, product sampling and distribution requirements, and complying with FDA promotion and advertising requirements, which include, among others, standards for direct-to-consumer advertising, restrictions on promoting products for uses or in patient populations that are not described in the product’s approved uses (known as “off-label use”), limitations on industry-sponsored scientific and educational activities, and requirements for promotional activities involving the internet. Although a physician may prescribe a legally available product for an off-label use, if the physician deems such product to be appropriate in his/her professional medical judgment, a manufacturer may not market or promote off-label uses. However, it is permissible to share in certain circumstances truthful and not misleading information that is consistent with the product’s approved labeling.

In addition, quality control and manufacturing procedures must continue to conform to applicable manufacturing requirements after approval to ensure the long-term stability of the product. cGMP regulations require among other things,

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quality control and quality assurance as well as the corresponding maintenance of records and documentation and the obligation to investigate and correct any deviations from cGMP. Manufacturers and other entities involved in the manufacture and distribution of approved products are required to register their establishments with the FDA and certain state agencies, and are subject to periodic unannounced inspections by the FDA and certain state agencies for compliance with cGMP and other laws. Accordingly, manufacturers must continue to expend time, money, and effort in the area of production and quality control to maintain cGMP compliance. Discovery of problems with a product after approval may result in restrictions on a product, manufacturer, or holder of an approved BLA, including, among other things, recall or withdrawal of the product from the market. In addition, changes to the manufacturing process are strictly regulated, and depending on the significance of the change, may require prior FDA approval before being implemented. Other types of changes to the approved product, such as adding new indications and claims, are also subject to further FDA review and approval.

The FDA also may require post-marketing testing, known as Phase 4 testing, and surveillance to monitor the effects of an approved product. Discovery of previously unknown problems with a product or the failure to comply with applicable FDA requirements can have negative consequences, including adverse publicity, judicial or administrative enforcement, warning letters from the FDA, mandated corrective advertising or communications with doctors, and civil or criminal penalties, among others. Newly discovered or developed safety or effectiveness data may require changes to a product’s approved labeling, including the addition of new warnings and contraindications, and also may require the implementation of other risk management measures. Also, new government requirements, including those resulting from new legislation, may be established, or the FDA’s policies may change, which could delay or prevent regulatory approval of our products under development.

Given the potential for long-lasting effects of CGT products, the FDA issued draft guidance in September 2025 describing methods and approaches for capturing post-approval safety and efficacy data for CGT products, including through approaches such as registries and other real-world data sources.

U.S. Marketing Exclusivity

The Biologics Price Competition and Innovation Act (BPCIA) amended the PHSA to authorize the FDA to approve similar versions of innovative biologics, commonly known as biosimilars. A competitor seeking approval of a biosimilar must file an application to establish its molecule as highly similar to an approved innovator biologic, among other requirements. The BPCIA, however, bars the FDA from approving biosimilar applications for 12 years after an innovator biological product receives initial marketing approval. This 12-year period of data exclusivity may be extended by six months, for a total of 12.5 years, if the FDA requests that the innovator company conduct pediatric clinical investigations of the product.

Depending upon the timing, duration and specifics of the FDA approval of the use of our product candidates, some of our U.S. patents, if granted, may be eligible for limited patent term extension under the Drug Price Competition and Patent Term Restoration Act of 1984, commonly referred to as the Hatch-Waxman Act. The Hatch-Waxman Act permits a patent restoration term of up to five years, as compensation for patent term lost during product development and the FDA regulatory review process. However, patent term restoration cannot extend the remaining term of a patent beyond a total of 14 years from the product’s approval date. The patent term restoration period is generally one-half the time between the effective date of an IND and the submission date of a BLA plus the time between the submission date of a BLA and the approval of that application. Only one patent applicable to an approved product is eligible for the extension and the application for the extension must be submitted prior to the expiration of the patent. The U.S. Patent and Trademark Office, in consultation with the FDA, reviews and approves the application for any patent term extension or restoration. In the future, we may intend to apply for restoration of patent term for one of our currently owned or licensed patents to add patent life beyond its current expiration date, depending on the expected length of the clinical trials and other factors involved in the filing of the relevant BLA.

Pediatric exclusivity is another type of regulatory market exclusivity in the United States. Pediatric exclusivity, if granted, adds six months to existing exclusivity periods and patent terms. This six-month exclusivity, which runs from the end of other exclusivity protection or patent term, may be granted based on the voluntary completion of a pediatric trial in accordance with an FDA-issued “Written Request” for such a trial.

FDA Approval and Regulation of Medical Devices and Companion Diagnostics

If safe and effective use of a therapeutic depends on an in vitro diagnostic, then the FDA generally will require approval or clearance of that diagnostic, known as a companion diagnostic, at the same time that the FDA approves the therapeutic product. In August 2014, the FDA issued final guidance clarifying the requirements that apply to approval of therapeutic products and in vitro companion diagnostics. According to the guidance, if the FDA determines that a companion diagnostic device is essential to the safe and effective use of a novel therapeutic product or indication, the FDA generally will not approve the therapeutic product or new therapeutic product indication if the companion diagnostic device is not approved or cleared for that indication. Approval or clearance of the companion diagnostic device will ensure that the device has been adequately evaluated and has adequate performance characteristics in the intended population. The review of in vitro

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companion diagnostics in conjunction with the review of our product candidates in development for cancer will, therefore, likely involve coordination of review by the FDA’s Center for Drug Evaluation and Research and the FDA’s Center for Devices and Radiological Health Office of In Vitro Diagnostics and Radiological Health.

Under the FDCA, in vitro diagnostics, including companion diagnostics, are regulated as medical devices. In the U.S., the FDCA and its implementing regulations, and other federal and state statutes and regulations govern, among other things, medical device design and development, preclinical and clinical testing, premarket clearance or approval, registration and listing, manufacturing, labeling, storage, advertising and promotion, sales and distribution, export and import, and post-market surveillance. Unless an exemption applies, medical devices, including companion diagnostic tests, require marketing clearance or approval from the FDA prior to commercial distribution.

The two primary types of FDA marketing authorization applicable to a medical device are premarket notification (“510(k) clearance”) and premarket approval (“PMA”). To obtain 510(k) clearance, a manufacturer must submit to the FDA a premarket notification submission demonstrating that the proposed device is “substantially equivalent” to a legally marketed predicate device. The FDA’s 510(k) clearance process usually takes from three to twelve months but may take longer. The FDA may require additional information, including clinical data, to make a determination regarding substantial equivalence. If the FDA agrees that the device is substantially equivalent to a predicate device currently on the market, it will grant 510(k) clearance to commercially market the device. If the FDA determines that the device is “not substantially equivalent” to a previously cleared device, the device is automatically designated as a Class III (i.e., high-risk) device. The device sponsor must then fulfill more rigorous PMA requirements or can request a risk-based classification determination for the device in accordance with the “de novo” process, which is a route to market for novel medical devices that are low to moderate risk and are not substantially equivalent to a predicate device.

After a device receives 510(k) clearance, any modification that could significantly affect its safety or effectiveness, or that would constitute a major change or modification in its intended use, will require a new 510(k) clearance or depending on the modification, approval of a PMA application or de novo classification. The FDA requires each manufacturer to determine whether the proposed change requires submission of a 510(k), de novo classification or a PMA in the first instance, but the FDA can review any such decision and disagree with a manufacturer’s determination. If the FDA disagrees with a manufacturer’s determination, the FDA can require the manufacturer to cease marketing and/or request the recall of the modified device until it receives 510(k) clearance, approval of a PMA application, or issuance of a de novo classification. Also, in these circumstances, the manufacturer may be subject to significant regulatory fines or penalties.

The PMA process, including the gathering of clinical and preclinical data and the submission to and review by the FDA, can take several years or longer. It involves a rigorous premarket review during which the applicant must prepare and provide the FDA with reasonable assurance of the device’s safety and effectiveness and information about the device and its components regarding, among other things, device design, manufacturing and labeling. PMA applications are subject to an application fee. In addition, PMAs for certain devices must generally include the results from extensive preclinical and adequate and well-controlled clinical trials to establish the safety and effectiveness of the device for each indication for which FDA approval is sought. In particular, for a diagnostic, a PMA application typically requires data regarding analytical and clinical validation studies. As part of the PMA review, the FDA will typically inspect the manufacturer’s facilities for compliance with the QSR which imposes elaborate testing, control, documentation and other quality assurance requirements.

Approval of a PMA is not guaranteed, and the FDA may ultimately respond to a PMA submission with a not approvable determination based on deficiencies in the application and require additional clinical trial or other data that may be expensive and time-consuming to generate and that can substantially delay approval. If the FDA’s evaluation of the PMA application is favorable, the FDA typically issues an approvable letter requiring the applicant’s agreement to specific conditions, such as changes in labeling, or specific additional information, such as submission of final labeling, in order to secure final approval of the PMA. If the FDA’s evaluation of the PMA or manufacturing facilities is not favorable, the FDA will deny approval of the PMA or issue a not approvable letter. A not approvable letter will outline the deficiencies in the application and, where practical, will identify what is necessary to make the PMA approvable. The FDA may also determine that additional clinical trials are necessary, in which case the PMA may be delayed for several months or years while the trials are conducted and then the data submitted in an amendment to the PMA. If the FDA concludes that the applicable criteria have been met, the FDA will issue a PMA for the approved indications, which can be more limited than those originally sought by the applicant. The PMA can include post-approval conditions that the FDA believes necessary to ensure the safety and effectiveness of the device, including, among other things, restrictions on labeling, promotion, sale and distribution. Once granted, approval may be withdrawn by the FDA if compliance with post approval requirements, conditions of approval or other regulatory standards are not maintained, or problems are identified following initial marketing.

After a device is placed on the market, it remains subject to significant regulatory requirements. Medical devices may be marketed only for the uses and indications for which they are cleared or approved. Device manufacturers must also establish registration and device listings with the FDA. A medical device manufacturer’s manufacturing processes and those of its suppliers are required to comply with the applicable portions of the QSR, which cover the methods and documentation of the

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design, testing, production, processes, controls, quality assurance, labeling, packaging and shipping of medical devices. Domestic facility records and manufacturing processes are subject to periodic unscheduled inspections by the FDA. The FDA also may inspect foreign facilities that export products to the U.S.

Other U.S. Healthcare Laws and Compliance Requirements

In the United States, our activities are potentially subject to regulation by various federal, state and local authorities in addition to the FDA, including but not limited to, the Centers for Medicare & Medicaid Services (CMS), other divisions of the U.S. Department of Health and Human Services (HHS) (e.g., the Office of Inspector General, the U.S. Department of Justice (DOJ), and individual U.S. Attorney offices within the DOJ, and state and local governments). For example, our business practices, including any of our research and future sales, marketing and scientific/educational grant programs may be required to comply with the anti-fraud and abuse provisions of the Social Security Act, the false claims laws, the patient data privacy and security provisions of the Health Insurance Portability and Accountability Act (HIPAA), transparency requirements, and similar state, local and foreign laws, each as amended.

ALLO US Equity

ALLO · 10-K · period ended 2025-12-31

Item 1. Business

ALLO US Equity☆

ALLO · 10-K · period ended 2025-12-31

Item 1. Business

ALLO US Equity