Bria-IMT Plus Checkpoint Inhibition Achieves 52% One-Year Survival in Metastatic Breast Cancer

Bria-IMT, an investigational allogeneic vaccine, combined with immune checkpoint inhibitors has demonstrated a 52% one-year overall survival rate in patients with heavily pretreated metastatic breast cancer, according to a recent study published on July 8, 2025. This trial enrolled 25 patients who had undergone a median of six prior lines of therapy, including those with hormone receptor-positive, HER2-positive, and triple-negative breast cancer. The findings underscore the potential of Bria-IMT in providing significant survival benefits for individuals who have limited treatment options.

The phase 2 trial (NCT03328026) highlighted that the combination treatment of Bria-IMT with retifanlimab resulted in promising outcomes. Patients with hormone receptor-positive breast cancer exhibited a median overall survival of 17.3 months, significantly higher than historical controls, which reported a median survival of 14.4 months for the standard treatment sacituzumab govitecan-hziy (Trodelvy).

Dr. Aditya Bardia, a professor in the Department of Medicine at UCLA Health and director of Translational Research Integration, noted the implications of these findings. "Many patients with metastatic breast cancer experience disease progression despite existing treatments, including checkpoint inhibitors and antibody-drug conjugates," he stated. "The survival data from this single-arm phase 2 trial highlight the potential activity of Bria-IMT in combination with checkpoint inhibitors, warranting further research in a phase 3 randomized clinical trial (NCT06072612)."

The study's results confirm Bria-IMT's favorable safety profile while enhancing overall survival in patients who have exhausted other treatment avenues. Adam M. Brufsky, MD, PhD, a professor of medicine at the University of Pittsburgh School of Medicine, remarked, "BriaCell’s phase 2 data indicate a robust survival signal and a well-tolerated profile. These results reinforce BriaCell’s potential to improve survival and tolerability for late-stage patients."

The trial included stringent eligibility criteria, requiring participants to have histologically confirmed recurrent or metastatic breast cancer that progressed despite prior therapies. Specifically, patients with hormone receptor-positive or HER2-positive breast cancer had to be refractory to hormonal therapy and treated with at least two regimens, including two anti-HER2 agents. Those with triple-negative breast cancer were required to have undergone treatment with standard therapies prior to participation.

The safety of the regimen was the primary endpoint of the trial, while secondary endpoints included overall response rates and duration of response. As the data continues to evolve, the oncology field remains cautiously optimistic about the potential of Bria-IMT in reshaping treatment paradigms for metastatic breast cancer patients facing dire circumstances.

The implications of this study extend beyond individual patient outcomes, as they signal a potential shift in treatment strategies for a particularly challenging subset of breast cancer patients. The data ensures that researchers and clinicians will closely monitor the ongoing phase 3 trial results to determine the efficacy and safety of Bria-IMT combined with checkpoint inhibitors in broader populations facing metastatic breast cancer.