BriaCell’s Bria-OTS+™ Mechanism of Action Validated in Highly Rated Peer Reviewed Cancer Journal

PHILADELPHIA and VANCOUVER, British Columbia, Aug. 26, 2025 (GLOBE NEWSWIRE) --BriaCell Therapeutics Corp. (Nasdaq: BCTX, BCTXW, BCTXZ), (TSX: BCT)(“BriaCell” or the “Company”), a clinical-stage biotechnology company developing novel immunotherapies to transform cancer care, today announced the publication of the mechanism of action of its next generation personalized off-the-shelf immunotherapy. This research conducted in collaboration with the National Cancer Institute (NCI), the US federal government’s principal agency for cancer research and training, has been published at JCI Insight, a highly rated peer-reviewed journal dedicated to advancing biomedical research from preclinical discovery through to clinical development.

Publication Title:Enhancing dendritic cell cancer vaccine by allogeneic MHC class II expression and Treg depletion (our reference 189024-INS-RG-RV-4)

“These findings help us better understand the anti-tumor effects of Bria-OTS+ in cancer patients,” stated Jay A. Berzofsky, MD, PhD, Senior Investigator of NCI and coauthor of the publication. “The study demonstrated that semi-allogeneic dendritic-cell vaccines recruit alloreactive CD4⁺ T-cell help through mismatched MHC class II molecules, which in turn strengthens antigen-specific CD8⁺ T-cell responses against tumors.”

“This publication validates the core design principle behind Bria-OTS+: partial HLA matching enables effective tumor-antigen presentation, while planned HLA mismatching drives robust CD4⁺ helper responses,” noted Miguel Lopez-Lago, PhD, BriaCell’s Chief Scientific Officer. “These findings are directly aligned with BriaCell’s pipeline of allogeneic immunotherapies, reinforcing our strategy to deliver powerful and scalable treatments for cancer patients.”

“These data are consistent with the encouraging clinical results we recently reported in our Phase 1/2a study in metastatic breast cancer and provide important insights into the mechanism of action of our cellular immunotherapy platform technology,” added Dr. William V. Williams, BriaCell’s President and CEO.

For the copy of the publication, please visit:https://briacell.com/scientific-publications/.

Bria-OTS is a next generation, off-the-shelf personalized immunotherapy based on BriaCell’s lead candidate Bria-IMT currently being evaluated in a Phase 1/2a study (ClinicalTrials.gov identifier:NCT06471673) in patients with metastatic recurrent breast cancer. The trial includes both monotherapy dose escalation and check point inhibition combination dose expansion cohorts. The Company recently progressed into the dose expansion phase.

BriaCell is a clinical-stage biotechnology company that develops novel immunotherapies to transform cancer care. More information is available athttps://briacell.com/.

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 include statements regarding Bria-OTS+’s potential to address urgent unmet medical needs for patients with cancer; and BriaCell delivering powerful and scalable treatments for cancer patients. These statements 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+ atwww.sedarplus.caand on EDGAR atwww.sec.gov. 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.

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