BriaCell Confirms 100% Resolution of Lung Metastasis With Bria-OTS

BriaCell Therapeutics Corp. confirms the sustained complete resolution of the lung metastasis, first reported in February 2025, two months after initial treatment in the ongoing Phase 1/2 Bria-OTS study. The latest data at four months also demonstrates stable disease elsewhere.

Figure 1: Treatment with Bria-OTS monotherapy resulted in 100% resolution of tumor in the lung of the metastatic breast cancer (MBC) patient following 2 months of therapy and confirmed at 4 months of therapy (axial and coronal views).

As shown, the lesion in the patient’s right lung is undetectable after two months and confirmed resolved at 4 months. The updated images supersede those previously reported.

The patient, a 78-year-old woman with metastatic breast cancer (hormone receptor positive, HER2 negative), had failed several prior lines of therapy and received the lowest dose level in the Phase 1/2a Bria-OTS study. At enrollment on November 21, 2024, she had extensive metastases including bone, lymph node and lung involvement. Following Bria-OTS intradermal injections every 2 weeks for six weeks (4 total doses), and subsequent dosing every 3 weeks, the lung metastasis completely resolved with stable disease elsewhere. This response is now confirmed and shows the potentially promising activity of the Bria-OTS platform as monotherapy.

“Despite recent advancements with Antibody-drug-conjugates (ADCs) and immune check point inhibitors (CPIs), many patients, including those with HR+ disease, like BriaCell’s first OTS patient, have very few options,” stated Neal S. Chawla, MD, Director at the Sarcoma Oncology Center, Santa Monica, CA, and Principal Investigator for the Bria-OTS study. “We are thrilled with our initial data with single agent Bria-OTS showing rapid and strong anti-tumor activity in an HR+ patient and look forward to continuing this novel approach in patients with MBC, and other cancers.”

“This unprecedented anti-cancer response in the first patient dosed with Bria-OTS is an important milestone for us and provides early validation of BriaCell’s personalized immunotherapy approach,” stated Dr. William V. Williams, BriaCell’s President and CEO.

Bria-OTS is a personalized off-the-shelf immunotherapy, currently under investigation in a Phase 1/2a dose escalation study (ClinicalTrials.gov identifier: NCT06471673) in metastatic recurrent breast cancer. Bria-OTS represents a personalized, next generation, advancement of BriaCell’s lead candidate Bria-IMT™ which is currently in a pivotal Phase 3 study for metastatic breast cancer. The Phase 1/2a clinical trial in metastatic breast cancer is a dose escalation study initially evaluating the safety and efficacy of Bria-OTS as monotherapy and will be followed by Bria-OTS in combination with an immune checkpoint inhibitor.

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