BriaCell Phase 3 Bria-IMT™ Study Enrollment Surpasses 230 Patients

• Over 315 patients screened and over 230 patients enrolled in BriaCell’s pivotal Phase 3 Bria-ABC study of Bria-IMT plus immune checkpoint inhibitor in metastatic breast cancer

• Enrollment momentum continues with strong clinical site and patient interest

• Interim topline data expected in 2026

• Positive interim overall survival results could support potential approval of Bria-IMT in metastatic breast cancer

• BriaCell’s Bria-IMT combination regimen continues under FDA Fast Track designation

PHILADELPHIA and VANCOUVER, British Columbia, May 12, 2026 (GLOBE NEWSWIRE) -- BriaCell Therapeutics Corp. (Nasdaq: BCTX, BCTXL) (TSX: BCT) (“BriaCell” or the “Company”), a clinical-stage biotechnology company developing novel immunotherapies to transform cancer care, announces that its pivotal Phase 3 Bria-ABC study has screened over 315 and enrolled over 230 patients. BriaCell anticipates reporting topline data in 2026.

BriaCell has received increased interest from leading cancer centers and continued enrollment momentum following theindependent inclusionof its Phase 3 clinical trial inNature Medicine’sarticle,“Eleven clinical trials that will shape medicine in 2026”. The Phase 3 Bria-ABC study is evaluating BriaCell’s lead clinical candidate, Bria-IMT, in combination with an immune checkpoint inhibitor versus physician’s choice of treatment inadvancedbreastcancer.

The interim analysis will be conducted after 144 patient events, defined as deaths, have occurred. Overall survival (OS) is the primary endpoint, and positive results could support full approval of Bria-IMT in patients with metastatic breast cancer. The Bria-IMT combination regimen has received FDA Fast Track designation.

“Sustained and new interest from world class institutions and their patients continues to drive remarkable patient engagement,” stated Dr. William V. Williams, BriaCell’s President & CEO. “We remain on track to report the interim analysis in 2026 while continuing to enroll patients and advance preparations for potential commercialization, with the goal of bringing our novel immunotherapy regimen to patients with metastatic breast cancer as efficiently as possible.”

For additional information on BriaCell’s pivotal Phase 3 study, please visit ClinicalTrials.govNCT06072612.

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, including those about ongoing patient enrollment in the pivotal Phase 3 clinical study of Bria‑IMT, the expected timing of interim analysis and topline data readout, and the potential for full approval and marketing authorization of the Bria‑IMT combination regimen, 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, such as those 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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