Agenus to Host March 2026 Stakeholder Webcast Harnessing the Immune System to Advance BOT + BAL Across Tumor Types and Expand Patient Access

Webcast on Tuesday, March 31, 2026, at 4:30 p.m. ET

LEXINGTON, Mass.--(BUSINESS WIRE)--Agenus Inc. (“Agenus”) (Nasdaq: AGEN), a leader in immuno-oncology, today announced it will host its March Stakeholder Webcast focused on continued progress of its botensilimab and balstilimab (BOT+BAL) immunotherapy program and will provide an update on the Company’s patient access programs, development across tumor types, and key priorities for 2026.

The session will be moderated by Garo H. Armen, PhD, Founder, Chairman, and Chief Executive Officer of Agenus, and will conclude with a live Q&A.

Featured Topics and Speakers

1. Strategic Direction: Advancing BOT+BAL
   Garo Armen, PhD
   Founder, Chairman, and Chief Executive Officer, Agenus
   Dr. Armen will open the session by discussing Agenus’ mission to harness the immune system across tumor types and the urgency of advancing new options for patients with historically treatment-resistant cancers. He will also outline key priorities for 2026 as momentum continues to build across the BOT+BAL program.
   
   
2. Clinical Progress: Durability and Consistency Across Tumors
   Steven J. O’Day, MD
   Chief Medical Officer, Agenus
   Dr. O’Day will provide a clinical perspective on the durability and consistency of BOT+BAL across tumor types, including in historically immunotherapy-resistant cancers. He will also highlight how these data are informing ongoing development and later-stage trials.
   
   
3. Access and Execution: Expanding Patient Through Available Global Programs
   Kamel Djazouli, MD
   Head, Medical Affairs, Agenus
   Dr. Djazouli will provide an update on Agenus’ global access programs, including the France AAC and Named Patient Programs, and how they are enabling treatment for patients with limited options.

Stakeholder Briefing Details:

Registration Link: https://vimeo.com/event/5828543
Live webcast link will be provided once registration is completed.

Submit questions in advance at: https://app.sli.do/event/qBiptRwcnamAfzRhiQnExc

This session marks the second event in Agenus’ 2026 Stakeholder Briefing Series, building on prior discussions regarding BOT+BAL’s clinical progress, patient access pathways, and Agenus corporate milestones.

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 is a multifunctional, human Fc enhanced CTLA-4 blocking 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.

Botensilimab alone, or in combination with Agenus’ investigational PD-1 antibody, balstilimab, has shown clinical responses across nine metastatic, late-line cancers. Approximately 1,200 patients have been treated across the botensilimab/balstilimab program in phase 1 and phase 2 clinical trials. 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 >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 the botensilimab and balstilimab clinical programs, expected trial initiations and regulatory plans, and the potential benefits of the combination therapy. Words such as “may,” “believes,” “expects,” “anticipates,” “hopes,” “intends,” “plans,” “forecasts,” “estimates,” “will,” “potential,” and similar expressions are intended to identify forward-looking statements. These statements are subject to risks and uncertainties that could cause actual results to differ materially from current expectations. Factors that could cause actual results to differ include, but are not limited to, those described under the “Risk Factors” section of Agenus’ most recent Annual Report on Form 10-K for 2025 and subsequent Quarterly Reports on Form 10-Q filed with the SEC. Agenus cautions investors not to place undue reliance on forward-looking statements in this release, which speak only as of the date of this announcement. The company undertakes no obligation to update or revise these statements, except as required by law. All forward-looking statements are expressly qualified in their entirety by this cautionary statement.