BriaCell Reports Positive Overall Survival in Metastatic Breast Cancer

BriaCell Therapeutics Corp. recently announced positive overall survival data of its Phase 2 clinical study of Bria-IMT in combination with an immune check point inhibitor (CPI) in late stage metastatic breast cancer.

Median overall survival of 15.6 months is reported in BriaCell’s most recent patients (treated since 2022) vs. 6.7-9.3 months for similar patients reported in the literature (see table below). These patients are being treated with the same Bria-IMT™ formulation currently being used in BriaCell’s ongoing Phase 3 pivotal study in metastatic breast cancer (listed on ClinicalTrials.gov as NCT06072612) and represent patients enrolled post-COVID when full study activities resumed.

This represents a substantial improvement over BriaCell’s 13.4 months median overall survival previously reported in December 2023.

“Overall survival in patients with heavily pre-treated metastatic breast cancer is very poor,” stated Sara A. Hurvitz, MD, Professor of Medicine, Fred Hutch Cancer Center and University of Washington and BriaCell medical advisory board member. “The BriaCell early data is quite encouraging from both efficacy and tolerability standpoints.”

“We wanted to look at the Phase 2 data of those patients who most closely resemble the patients being treated in our ongoing phase 3 study and compare them to similar patients in the literature,” stated Dr. William V. Williams, BriaCell’s President and CEO. “The nearly two-fold overall survival benefit we are seeing with the Bria-IMT regimen, together with the similar previously reported approximate doubling of progression free survival, compared with literature controls, strongly support our belief that Bria-IMT™ could have a meaningful impact in the lives of heavily pre-treated metastatic breast cancer patients. We look forward to further clinical development of Bria-IMT™ with the goal of establishing it as a new standard of care for patients with metastatic breast cancer.”

“The Bria-IMT regimen is the only investigational drug we have seen to show these impressive survival numbers in heavily pre-treated metastatic breast cancer patients who have failed numerous prior treatments including immune check point inhibitors and antibody drug conjugates,” stated Giuseppe Del Priore, MD, MPH, BriaCell’s Chief Medical Officer. “These survival and clinical benefit data support BriaCell’s hypothesis of additive and/or synergistic effects of immune check point inhibitors with Bria-IMT™ and drive the ongoing pivotal study of our combination regimen in the treatment of metastatic breast cancer.”

The Phase 2 study enrolled 54 heavily pre-treated metastatic breast cancer patients (average number of prior treatments = 6) who were treated with the Bria-IMT regimen and an immune checkpoint inhibitor. Of these 54 patients, 37 were treated with the Phase 3 formulation and 25 of these were treated post-COVID when full study activities resumed. This data represents an additional six months of follow-up of the survival data presented at the San Antonio Breast Cancer Symposium in December 2023.

Table 1. Comparative Median Overall Survival (OS) and Progression-Free Survival (PFS) in Similar Patients (Interim Analysis Using Kaplan-Meier Estimate)

References

1. Bardia A, et al. Final Results From the Randomized Phase III ASCENT Clinical Trial in Metastatic Triple-Negative Breast Cancer and Association of Outcomes by Human Epidermal Growth Factor Receptor 2 and Trophoblast Cell Surface Antigen 2 Expression. J Clin Oncol. 2024 May 20;42(15):1738-1744. doi: 10.1200/JCO.23.01409. Epub 2024 Feb 29. PMID: 38422473.
2. Tripathy D, et al. Treatment with etirinotecan pegol for patients with metastatic breast cancer and brain metastases: final results from the phase 3 ATTAIN randomized clinical trial. JAMA Oncol. 2022;8(7):1047-1052. doi:10.1001/jamaoncol.2022.0514.
3. O’Shaughnessy J et al. Analysis of patients without and with an initial triple-negative breast cancer diagnosis in the phase 3 randomized ASCENT study of sacituzumab govitecan in metastatic triple-negative breast cancer. Breast Cancer Res Treat. 2022 Sep;195(2):127-139. doi: 10.1007/s10549-022-06602-7. Epub 2022 May 11. PMID: 35545724; PMCID: PMC9374646.
4. Cortes J, Perez-Garcia J, Levy C, Gómez Pardo P, Bourgeois H, Spazzapan S, Martínez-Jañez N, Chao TC, Espié M, Nabholtz JM, Gonzàlez Farré X, Beliakouski V, Román García J, Holgado E, Campone M. Open-label randomised phase III trial of vinflunine versus an alkylating agent in patients with heavily pretreated metastatic breast cancer. Ann Oncol. 2018 Apr 1;29(4):881-887. doi: 10.1093/annonc/mdy051. PMID: 29481630.

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/.