BriaCell Presents Robust Anti-Cancer Activity of Bria-OTS+™ in Preclinical Cancer Models

• Bria-OTS+ platform provides early, potent and durable activation of innate and adaptive immunity in in-vitro cancer cell line models
• Immune cells activated by Bria-OTS+ exhibit serial killing activity across multiple rounds of tumor cell challenge

PHILADELPHIA and VANCOUVER, British Columbia, April 21, 2026 (GLOBE NEWSWIRE) -- BriaCell Therapeutics Corp. (Nasdaq: BCTX, BCTXL) (TSX: BCT) (“BriaCell” or the “Company”), a clinical-stage biotechnology company that develops novel immunotherapies to transform cancer care, is presenting positive data from its preclinical Bria-OTS+ platform at the 2026 American Association for Cancer Research (AACR) Annual Meeting taking place April 17–22 at the San Diego Convention Center in San Diego, California.

The poster is summarized below and linked here: .

Title: Re-Engineering Cancer Vaccines: Bria-OTS+ Integrates Innate and Adaptive Immunity for Broad and Persistent Anti-Tumor Responses

Session Category: Clinical Research

Session Title: Vaccines and Other Immunomodulatory Agents

Session: 4/21/2026 2:00-5:00 PM

Location: Poster Section 49

Poster Board Number: 12

Poster Number: 6701

Summary: Bria-OTS+ is a personalized, off-the-shelf, next-generation genetically engineered whole-cell cancer immunotherapy platform designed to enhance efficacy and safety. Our results demonstrate that Bria-OTS+ activates key components of both the innate and adaptive immune systems to broadly target and destroy cancer cells across solid tumors. These effects include coordinated activation of CD4⁺ and CD8⁺ T cells, NK cells, NKT cells, dendritic cells, and B cells, together with increased cytokine release and sustained immune competence without exhaustion—helping address an important mechanism of cancer progression.

Data presented includes the following:

• Rapid activation of innate and adaptive immune responses: Bria-BRES+ (breast cancer) and Bria-PROS+ (prostate cancer) drove early activation and proliferation of key immune cells including CD4+ and CD8+ T cells, NK cells, and NKT cells, enhanced cytotoxic activity against parental tumor targets, and increased CD80/CD86 expression on dendritic and B cells, consistent with improved antigen-presentation.
• Sustained, long-lasting and targeted anti-tumor activity: Bria-BRES+ and Bria-PROS+ generated durable cytokine responses and maintained cytotoxic, serial killing activity through repeated cancer cell challenges without evidence of functional exhaustion. Bria-OTS+ also showed limited induction of immunosuppressive cell populations including regulatory T cells (Tregs) and myeloid-derived suppressor cells (MDSCs).
• Broad tumor recognition may reduce escape risk: Bria-BRES+ and Bria-PROS+ cells demonstrated anti-tumor activity against multiple tumor targets, supporting the potential of Bria-OTS+ to drive broad, cross-tumor immune responses, reduce immune escape, and limit cancer progression.
  
  
• Bria-OTS+ proposed mechanism of action: Following intradermal administration, Bria-OTS+ is designed to activate T cells and NK cells directly, while professional antigen-presenting cells (APCs) take up tumor specific antigens, migrate to regional lymph nodes and prime tumor-specific T cells to drive a systemic anti-tumor immune response.
  
  

Miguel A. Lopez-Lago, PhD, BriaCell’s Chief Scientific Officer, commented, “We are thrilled with our data showing early, strong, and long-lasting anti-cancer activity of Bria-OTS+ in multiple cancer models, boosting the immune system response, and potentially overcoming common cancer cell resistance mechanisms. Our findings strongly support targeted anti-cancer effects of Bria-OTS+ and warrant additional testing of the Bria-OTS+ platform in clinical settings.”

“Based on these promising preclinical findings, we are advancing Bria-OTS+ with the goal of entering the clinic for our first indications of metastatic breast cancer and prostate cancer later this year, with additional indications (lung cancer and melanoma) planned for 2027,” added Dr. William V. Williams, BriaCell’s President and CEO.

About BriaCell Therapeutics Corp.

BriaCell is a clinical-stage biotechnology company that develops novel immunotherapies to transform cancer care. More information is available at .

Safe Harbor

This press release contains “forward-looking statements” that are subject to substantial risks and uncertainties. All statements, other than statements of historical fact, contained in this press release are forward-looking statements. Forward-looking statements contained in this press release may be identified by the use of words such as “anticipate,” “believe,” “contemplate,” “could,” “estimate,” “expect,” “intend,” “seek,” “may,” “might,” “plan,” “potential,” “predict,” “project,” “target,” “aim,” “should,” “will,” “would,” or the negative of these words or other similar expressions, although not all forward-looking statements contain these words. Forward-looking statements, including those about: BriaCell presenting positive data from its preclinical Bria-OTS+ platform at the AACR , and BriaCell’s expectations that the Bria-OTS+ platform will enable the delivery of powerful and long-lasting immune activity against cancer; whether additional immune activating factors will enhance efficacy of the Bria-OTS+ platform; whether prior results will be replicated in clinical studies of the next generation Bria-BRES+ breast cancer and Bria-PROS+ prostate cancer programs utilizing the Bria‑OTS+ platform; and expectations for what will be investigated in BriaCell’s planned Phase 1/2a clinical studies of Bria-OTS+; are based on BriaCell’s current expectations and are subject to inherent uncertainties, risks, and assumptions that are difficult to predict. Further, certain forward-looking statements are based on assumptions as to future events that may not prove to be accurate. These and other risks and uncertainties are described more fully under the heading “Risks and Uncertainties” in the Company's most recent Management’s Discussion and Analysis, under the heading "Risk Factors" in the Company's most recent Annual Information Form, and under “Risks and Uncertainties” in the Company's other filings with the Canadian securities regulatory authorities and the U.S. Securities and Exchange Commission, all of which are available under the Company's profiles on SEDAR+ at  and on EDGAR at . Forward-looking statements contained in this announcement are made as of this date, and BriaCell Therapeutics Corp. undertakes no duty to update such information except as required under applicable law.

Neither the Toronto Stock Exchange nor its Regulation Services Provider (as that term is defined in the policies of the Toronto Stock Exchange) accepts responsibility for the adequacy or accuracy of this release.

Contact Information

Company Contact:

William V. Williams, MD

President & CEO

1-888-485-6340

 

Investor Relations Contact: