BriaCell and BriaPro Present Positive Preclinical Immunotherapy Data Across Four Posters at SITC 2026

• Bria-OTS+™ demonstrates broad immune activation and sustained cancer-cell killing across multiple tumor models
• BriaPro data highlights BP-80 tolerability in primates and advances in tumor-targeted checkpoint inhibition

PHILADELPHIA and VANCOUVER, British Columbia, Nov. 06, 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, and its majority-owned subsidiary, BriaPro Therapeutics Corp. (“BriaPro”), today announced preclinical findings from four posters at the Society for Immunotherapy of Cancer (SITC) 41^th Anniversary Annual Meeting, taking place November 4-8, 2026, in Phoenix, AZ.

The presentations highlight BriaCell’s Bria-OTS+ off-the-shelf cellular immunotherapy platform and BriaPro’s BP-80 and TILsRx immunotherapy programs, including advances in engineered CD80 proteins.

“These findings provide additional preclinical support for our cellular immunotherapy and checkpoint inhibitor programs, including Bria-BRES+ in breast cancer and Bria-PROS+ in prostate cancer,” stated William V. Williams, MD, BriaCell’s President and CEO. “The results support continued development of our immunotherapy pipeline across multiple cancer indications.”

Highlights of the SITC 2026 Presentations

BriaCell

Title: A Multifaceted Genetically Engineered Whole-Cell Vaccine Platform Generates Potent, Broad, Persistent, and Effector-Centric Anti-Tumor Immunity Across Multiple Cancer Indications
Abstract Number: 863
Location: PCC-North Building-Lower Level-Exhibition Halls 4-5-6
Date: Friday, Nov. 6, 2026
Time: 12:15 - 1:45 PM, 5:30 - 7:00 PM MT

Key Findings:
Bria-OTS+ demonstrated broad innate and adaptive immune activation, including stimulating immune cells from patients with breast and prostate cancer. Priming and boosting enhanced cancer-cell killing across multiple tumor cell lines, while repeated tumor challenges demonstrated sustained cytotoxic activity. Activity was also confirmed in Bria-OTS+-activated immune cells derived from cancer patients.

BriaPro

Title: Development of BP-80, a soluble CD80 dimer (CD80-Fc) for cancer treatment
Abstract Number: 404
Location: PCC-North Building-Lower Level-Exhibition Halls 4-5-6
Date: Saturday, Nov. 7, 2026
Time: 12:00 - 1:30 PM, 6:40 - 8:10 PM MT

Key Findings:
BP-80 demonstrated CD28 co-stimulatory activity and counteracted CTLA-4-mediated inhibition in cell-based assays. In a four-week GLP nonhuman primate study, BP-80 was well tolerated, with no treatment-related pathological findings and a No Observed Effect Level (NOEL) of 50 mg/kg/dose, well above the predicted clinically active dose.

Title: Tumor-targeted checkpoint inhibitors for reactivation of tumor-infiltrating lymphocytes
Abstract Number: 405
Location: PCC-North Building-Lower Level-Exhibition Halls 4-5-6
Date: Friday, Nov. 6, 2026
Time: 12:15 - 1:45 PM, 5:30 - 7:00 PM MT

Key Findings:
TILsRx-001, a B7-H3-targeting TILsRx construct with two CD80 extracellular domains (ECD), antagonized the immune inhibitory effect of PD-L1 in a cell-based surrogate assay. Engineered with two mutations in each CD80 ECD, TILsRx-001 demonstrated a 49-fold higher binding affinity for PD-L1 than the corresponding TILsRx construct without these CD80 mutations, supporting further development of TILsRx-001 as a tumor-targeted checkpoint inhibitor.

Title: Molecular design of CD80 variants with increased affinity for PD-L1 and wild-type or lower affinity for CD28
Abstract Number: 406
Location: PCC-North Building-Lower Level-Exhibition Halls 4-5-6
Date: Saturday, Nov. 7, 2026
Time: 12:00 - 1:30 PM, 6:40 - 8:10 PM MT

Key Findings:
Structure-guided engineering generated a soluble CD80 variant (CD80-Fc) with more than 130-fold stronger PD-L1 binding than CD80-Fc with wild-type CD80 sequence. Multiple CD80 mutations enhanced PD-L1 binding with no or only minimal effect on CD28 affinity, supporting the development of CD80-based immunotherapies.

Following the presentation, copies of the posters will be made available at https://briacell.com/scientific-publications/.

About BriaCell Therapeutics Corp.

BriaCell is an immuno-oncology-focused biotechnology company developing targeted and effective approaches for the management of cancer. More information is available at https://briacell.com/.

About BriaPro Therapeutics Corp.

BriaPro is a pre-clinical stage immunotherapy company developing binding agents and proteins with the intention to boost the ability of the body’s own cancer-fighting cells to destroy cancerous tumors.

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 and BriaPro presenting posters at the SITC 2026 Annual Meeting, and the contents of such posters, 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.

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
info@briacell.com 

Investor Relations Contact:
investors@briacell.com