Agenus Announces Data from Phase II Study of BOT+BAL in Combination with agent-797 in PD-1 Refractory Gastroesophageal Cancer to be Presented at AACR 2026

Key Terms

immunotherapy medical

Treatment that uses or enhances the body’s immune system to detect and fight disease, most often cancers or chronic infections; think of it as training or arming the body’s own soldiers to find and destroy targets. It matters to investors because successful immunotherapies can lead to high-value drug approvals, recurring revenue from long-term treatments, and changes in competitive dynamics, while failures or safety issues in clinical trials can materially affect company valuations.

allogeneic medical

Allogeneic describes a process or material involving different individuals of the same species, such as cells, tissues, or organs donated from one person to another. It is important to investors because products or treatments based on allogeneic sources can enable scalable, off-the-shelf solutions, potentially reducing costs and increasing accessibility in healthcare and biotech industries.

inkt cell therapy medical

iNKT (invariant natural killer T) cell therapy uses a patient’s or donor’s specialized immune cells that can both recognize diseased cells and call other immune cells into action, often engineered or expanded in a lab and then given back to the patient. Investors care because it represents a targeted, high-cost biotherapy approach with the potential for large clinical benefits and commercial returns, but also carries significant development, safety and regulatory risks like other novel cell therapies.

checkpoint inhibition medical

Checkpoint inhibition is a type of cancer treatment that blocks certain proteins on immune cells or tumors that act like brakes, allowing the body’s T cells to attack cancer more strongly. For investors, it matters because these therapies can transform clinical trial outcomes, drive regulatory approvals or safety concerns, and create large market opportunities or partnership and pricing questions—similar to taking the foot off a brake to speed up a car but increasing the risk of losing control.

pd-1 medical

PD-1 is a protein found on certain immune cells that acts like a brake, signaling the immune system to slow down and avoid damaging healthy tissue. Drugs that block PD-1 release that brake so immune cells can better attack cancer cells; because such therapies can produce large clinical benefits, regulatory approvals, trial outcomes, pricing and market uptake for PD-1 drugs can materially affect a drugmaker’s prospects and investor returns.

gastroesophageal cancer medical

Gastroesophageal cancer is a term for malignant tumors that arise in the esophagus (the food pipe) or the nearby upper stomach, often where those two meet. It matters to investors because diagnosis, treatment advances, drug approvals, clinical trial readouts and reimbursement decisions directly affect the commercial market for therapies and devices — think of it like a damaged stretch of pipeline that creates demand for repairs, diagnostics and long-term solutions.

• Study highlights novel multi-mechanistic immunotherapy combination in checkpoint-refractory disease
• Data expected to inform immune modulation, treatment sequencing, and durability of response across hard-to-treat tumors

LEXINGTON, Mass.--(BUSINESS WIRE)-- Agenus Inc. (Nasdaq: AGEN), a leader in immuno-oncology innovation, today announced that data from an investigator-initiated Phase II trial conducted at Memorial Sloan Kettering Cancer Center will be presented at the American Association for Cancer Research (AACR) Annual Meeting, taking place April 17–22, 2026, in San Diego, CA.

The study evaluates botensilimab (BOT) and balstilimab (BAL) in combination with agenT-797, an allogeneic iNKT cell therapy developed by MiNK Therapeutics, in patients with PD-1 refractory gastroesophageal cancer (GEC)—an area of significant unmet need where resistance to checkpoint inhibition remains a major clinical challenge.

Presentation Details:

Abstract Title: A phase II study of agenT-797, botensilimab (BOT) and balstilimab (BAL) in PD-1 refractory gastroesophageal cancer (GEC)

Presenter: Samuel L. Cytyrn, MD; Gastrointestinal Medical Oncologist, Memorial Sloan Kettering Cancer Center

Session Name: Phase II and Phase III Clinical Trials

Date/Time: April 20, 2026 | 2:00–5:00 PM PT; 5:00-8:00 PM EDT

Poster Section: 52

Abstract No.: CT166

About Agenus

Agenus is a leading immuno-oncology company targeting cancer with a comprehensive pipeline of immunological agents. The company was founded in 1994 with a mission to expand patient populations benefiting from cancer immunotherapy through combination approaches, using a broad repertoire of antibody therapeutics, adoptive cell therapies (through MiNK Therapeutics) and adjuvants. Agenus has robust end-to-end development capabilities, across commercial and clinical cGMP manufacturing facilities, research and discovery, and a global clinical operations footprint. Agenus is headquartered in Lexington, MA. For more information, visit www.agenusbio.com or @agenus_bio. Information that may be important to investors will be routinely posted on our website and social media channels.

About Botensilimab (BOT)

Botensilimab (BOT) is a human Fc enhanced multifunctional anti-CTLA-4 antibody designed to boost both innate and adaptive anti-tumor immune responses. Its novel design leverages mechanisms of action to extend immunotherapy benefits to “cold” tumors which generally respond poorly to standard of care or are refractory to conventional PD-1/CTLA-4 therapies and investigational therapies. Botensilimab augments immune responses across a wide range of tumor types by priming and activating T cells, downregulating intratumoral regulatory T cells, activating myeloid cells and inducing long-term memory responses.

Approximately 1,200 patients have been treated with botensilimab and/or balstilimab in phase 1 and phase 2 clinical trials. Botensilimab alone, or in combination with Agenus’ investigational PD-1 antibody, balstilimab, has shown clinical responses across nine metastatic, late-line cancers. For more information about botensilimab trials, visit www.clinicaltrials.gov.

About Balstilimab (BAL)

Balstilimab is a novel, fully human monoclonal immunoglobulin G4 (IgG4) designed to block PD-1 (programmed cell death protein 1) from interacting with its ligands PD-L1 and PD-L2. It has been evaluated in more than 900 patients to date and has demonstrated clinical activity and a favorable tolerability profile in several tumor types.

Forward-Looking Statements

This press release contains forward-looking statements that are made pursuant to the safe harbor provisions of the federal securities laws, including statements regarding its botensilimab and balstilimab programs, expected regulatory timelines and filings, and any other statements containing the words "may," "believes," "expects," "anticipates," "hopes," "intends," "plans," "forecasts," "estimates," "will," “establish,” “potential,” “superiority,” “best in class,” and similar expressions are intended to identify forward-looking statements. These forward-looking statements are subject to risks and uncertainties that could cause actual results to differ materially. These risks and uncertainties include, among others, the factors described under the Risk Factors section of our most recent Annual Report on Form 10-K for 2025, and subsequent Quarterly Reports on Form 10-Q filed with the Securities and Exchange Commission. Agenus cautions investors not to place considerable reliance on the forward-looking statements contained in this release. These statements speak only as of the date of this press release, and Agenus undertakes no obligation to update or revise the statements, other than to the extent required by law. All forward-looking statements are expressly qualified in their entirety by this cautionary statement.

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Source: Agenus Inc.