BCTX BriaCell Therapeutics Corporation

BriaCell Therapeutics Corp. (Nasdaq: BCTX, BCTXW) (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 Phase 2 study of lead product candidate, Bria-IMT™, in metastatic breast cancer, and from its preclinical Bria-OTS+ platform at the 2025 American Association for Cancer Research (AACR) Annual Meeting taking place from April 25th – 30th at McCormick Place Convention Center, Chicago, IL. In addition, Phase 3 early biomarker data will be presented as a late breaking abstract.

The posters are summarized below and linked here: https://briacell.com/scientific-publications/.

Title: Survival outcomes in a randomized phase 2 of Bria-IMT: An allogeneic whole cell cancer vaccineSession Title: Phase II and Phase III Clinical TrialsSession Start: 4/28/2025 2:00 PM – 5:00 PM CSTLocation: Poster Section 50Poster Board Number: 18Abstract Presentation Number: CT100

“We are thrilled to share impressive survival and clinical efficacy data at AACR on the advantages of using Bria-IMT plus checkpoint inhibitor in heavily treated patients who have failed multiple prior treatments, including ADCs and CPIs,” stated lead author, Saranya Chumsri, MD, Principal Investigator and Professor of Oncology, Mayo Clinic. “Treatment options have been limited for patients who progress after ADC therapy, making this a particularly challenging clinical setting. Our clinical findings support the use of Bria-IMT as a well-tolerated, alternative treatment option for these very difficult-to-treat patients with unmet medical needs.”

“The excellent survival responses reported in patients with different tumor types in the Phase 2 study is very exciting, and we look forward to seeing these promising data replicate in the pivotal Phase 3 study,” stated Dr. William V. Williams, BriaCell’s President & CEO.

Of 54 metastatic breast cancer patients in the Phase 2 study, 37 patients received Bria-IMT formulation that is currently being used in BriaCell’s ongoing pivotal Phase 3 study (ClinicalTrials.gov as NCT06072612). Patients have been heavily pre-treated a median of 6 prior treatments -- including Antibody-Drug Conjugates (ADCs) and check point inhibitors (CPIs).

• Clinical benefit rates [CR, PR, SD] ranged from 45% to 100% based on subtype
• Decrease in size or no change in all tumors noted in 83% of patients receiving Phase 3 formulation
• Overall survival (OS) with the Phase 3 formulation was 17.3 months for HR+ patients and 11.44 months for patients with triple negative breast cancer (TNBC)
• Overall response rate (ORR) for patients with intracranial metastases was 50% with a 75% clinical benefit rate
• Safety profile: No unexpected adverse events, no treatment related discontinuation of therapy

Title: Bria-OTS+: A versatile therapeutic platform for inducing anti-cancer immunitySession Category: ImmunologySession Title: Vaccines, In Situ Vaccines, and Vaccine CombinationsSession Date and Time: 4/28/2025 2:00 – 5:00 PM CSTLocation: Poster Section 39Poster Board Number: 29Published Abstract Number: 3553

Miguel A. Lopez-Lago, PhD, BriaCell’s Chief Scientific Officer, commented, “We are very excited with the anti-cancer activity of Bria-OTS+ and expect the platform will enable the delivery of powerful and long-lasting immune activity against cancer.”

“This data further validates the mechanism of action of our next-generation Bria-OTS+ platform. Additional immune activating factors are expected to enhance efficacy, and we look forward to replicating these results clinically as we advance our next generation Bria-BRES+ breast cancer and Bria-PROS+ prostate cancer programs,” stated Dr. William V. Williams, BriaCell’s President and CEO.

Bria-OTS+ is an immunotherapy platform and enhanced version of Bria-OTS™, BriaCell’s personalized pre-manufactured immunotherapy already demonstrating tremendous results as announced on April 24 2025. Bria-OTS+ immunotherapy expresses multiple immune-activating cytokines and co-stimulatory molecules in addition to immune-boosting granulocyte-macrophage colony-stimulating factor (GM-CSF). Bria-BRES+™ for breast cancer and Bria-PROS+™ for prostate cancer are expected to be investigated in BriaCell’s upcoming Phase 1/2a clinical studies.

About BriaCell Therapeutics Corp.

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

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 Phase 2 study of lead product candidate, Bria-IMT, in metastatic breast cancer, and from its preclinical Bria-OTS+ platform at the AACR as well as Phase 3 early biomarker data being presented at the AACR as a late breaking abstract; whether BriaCell will be able to see prior results replicated in the pivotal Phase 3 study; 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; and expectations for what will be investigated in BriaCell’s planned Phase 1/2a clinical studies; 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 www.sedarplus.ca and on EDGAR at www.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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Contact Information

Company Contact:William V. Williams, MDPresident & CEO1-888-485-6340info@briacell.com

Investor Relations Contact:investors@briacell.com