Bria-IMT Shows Extended Survival in Advanced Metastatic Breast Cancer

Updated phase 2 clinical data for the allogeneic whole-cell immunotherapy Bria-IMT (SV-BR-1-GM) demonstrate a robust survival signal in patients with heavily pretreated metastatic breast cancer.¹

The data highlight a median overall survival (OS) of 15.6 months in the recent cohort, with a 2-year survival rate of 32%. This compares favorably with historical data for physician-selected treatments, where 2-year survival typically ranges from 7% to 25%. The findings suggest that Bria-IMT may offer a meaningful therapeutic alternative for patients who have exhausted multiple lines of therapy, including antibody-drug conjugates (ADCs) and checkpoint inhibitors (CPIs).

Clinical Outcomes and Tolerability

The phase 2 study (NCT03066947) enrolled 54 patients with a median of 6 prior lines of therapy. Among the 25 patients treated with the current formulation since 2022, 9 remain alive as of the most recent assessment. Notably, the regimen, which includes low-dose cyclophosphamide and local interferon-alpha-2b, has been well-tolerated. To date, no patients have discontinued treatment due to adverse events related to Bria-IMT.

The clinical benefits were observed across multiple subtypes. In a comparative analysis, the 15.6-month median OS in the Bria-IMT plus CPI cohort exceeded the 14.4-month median OS reported for sacituzumab govitecan (Trodelvy) in hormone receptor-positive, HER2-negative (HER2–) metastatic breast cancer.² The survival signal was particularly pronounced in patients who had previously failed treatment with sacituzumab govitecan or trastuzumab deruxtecan (T-DXd; Enhertu).

Long-Term Response Case Studies

The update included several notable case studies of long-term survival. One 66-year-old patient with estrogen receptor-positive (ER+)/progesterone receptor-positive (PR+)/HER2-positive (HER2+) disease and 8 prior therapies, including T-DXd, presented with metastatic involvement of the right orbit, the temporal lobe of the brain, and multiple skeletal sites.¹ Following 35 cycles of the Bria-IMT regimen, the patient experienced complete resolution of the brain metastasis and substantial improvement in the orbital lesion. This patient remains in survival follow-up 27 months post enrollment.

Another patient, a 64-year-old with ER+/PR-negative (PR–)/HER2– disease who had previously failed 8 therapies, including sacituzumab govitecan, achieved a survival duration of 25 months. These cases underscore the potential for cellular immunotherapy to elicit durable responses in the setting of visceral and central nervous system metastases.

Mechanism of Action

Bria-IMT is a genetically modified, irradiated allogeneic breast cancer cell line transfected to secrete GM-CSF. The therapy functions as a targeted immunotherapy, intended to stimulate the patient’s immune system to recognize and attack tumor-associated antigens. By expressing HLA class I and II molecules, the cell line can directly activate CD4- and CD8-positive T cells, bypassing the requirement for traditional dendritic cell antigen processing in some contexts.

Future Directions

The promising survival data from the phase 2 cohorts have informed the design of the ongoing pivotal phase 3 BRIA-ABC trial (NCT06072612).³ This multicenter, randomized, open-label study is evaluating the Bria-IMT regimen in combination with the PD-1 inhibitor retifanlimab (Zynyz) vs physician’s choice of treatment. The primary end point is OS with secondary end points including progression-free survival and clinical benefit rate.

“Our drive to generate long term data reflects our belief that clinicians and cancer patients deserve clear, meaningful evidence to guide their treatment decisions. The number of long-term survivors is quite remarkable, given how heavily pre-treated these patients are, and supports our hypothesis that the Bria-IMT regimen prolongs survival in patients with metastatic breast cancer,” said William V. Williams, president and CEO of BriaCell, in a news release. “We look forward to confirming these findings in BriaCell’s ongoing pivotal phase 3 study with overall survival as its primary end point.”

REFERENCES

1. BriaCell highlights extended >18-47 months survival in phase 2 metastatic breast cancer patients. News release. BriaCell.January 27, 2026. Accessed January 28, 2026. https://tinyurl.com/28ffup3t

2. Rugo HS, Bardia A, Marmé F, et al. Overall survival with sacituzumab govitecan in hormone receptor-positive and human epidermal growth factor receptor 2-negative metastatic breast cancer (TROPiCS-02): a randomised, open-label, multicentre, phase 3 trial. Lancet. 2023 Oct 21;402(10411):1423-1433. doi: 10.1016/S0140-6736(23)01245-X. Epub 2023 Aug 23. PMID: 37633306.

3. Study of the Bria-IMT regimen and CPI vs physicians' choice in advanced metastatic breast cancer. (BRIA-ABC). ClinicalTrials.gov. Updated January 5, 2026. Accessed January 28, 2026. https://clinicaltrials.gov/study/NCT06072612