Bria-IMT Combo Shows Survival in Phase 2 Breast Cancer Trial

In a phase 2 study, 52% of patients treated with Bria-IMT plus a checkpoint inhibitor for metastatic breast cancer were alive at one year: © stock.adobe.com.

In a phase 2 study, 52% of patients with metastatic breast cancer remained alive at least one year after beginning a treatment regimen of Bria-IMT plus a checkpoint inhibitor, according to a news release from BriaCell.

“BriaCell’s phase 2 data indicate a robust survival signal and a well-tolerated profile,” Dr. Adam M. Brufsky, professor of medicine at the University of Pittsburgh School of Medicine and medical director of the Magee-Women's Cancer Program, said in the news release. “These results reinforce BriaCell’s potential to improve survival and tolerability for late-stage patients.”

As of the most recent follow-up, 11 patients remain alive, including one at 38.3 months and another at 30.3 months. This survival duration exceeds expectations based on outcomes seen with standard therapies for similar patients. Many had advanced metastatic breast cancer and had already received multiple treatments, including checkpoint inhibitors and antibody-drug conjugates such as Trodelvy (sacituzumab govitecan-hziy) and Enhertu (fam-trastuzumab deruxtecan-nxki). In addition, no patients stopped treatment due to side effects from Bria-IMT.

Five patients were identified as long-term responders to Bria-IMT treatment, demonstrating several months of survival. Patient 01-009, a 74-year-old, had 38.3 months of survival after undergoing five prior regimens and 13 cycles of Bria-IMT. Patient 07-001, aged 55, achieved 30.3 months of survival following seven prior regimens, including Enhertu, and eight cycles of Bria-IMT. Patient 11-018, a 66-year-old, survived 21.6 months, having received eight prior regimens and the highest number of Bria-IMT cycles at 28. Patient 11-019, aged 63, had 20 months of survival after nine prior regimens, including Trodelvy, and six cycles of Bria-IMT. Lastly, patient 16-003, an 80-year-old, showed 19.4 months of survival, having undergone five prior regimens, including Enhertu, and eight cycles of Bria-IMT.

In the comparable analysis, investigators reported a one-year survival of approximately 38% to 40% across all breast cancer types with a median of four prior lines of therapy. Other investigators observed a 30 to 38% one-year survival for all breast cancer types with a median of two prior lines. Some investigors, specifically for triple-negative breast cancer, with two to three prior lines, the one-year survival was about 23%. Finally, another research team showed a 47% one-year survival for hormone receptor positive HER2- breast cancer with two prior lines of therapy.

“Many patients with metastatic breast cancer unfortunately have disease progression despite treatment with checkpoint inhibitors and antibody-drug conjugates,” Dr. Aditya Bardia, a leading breast cancer expert, said in the news release. “BriaCell’s survival data in single arm phase 2 trial highlights the potential activity of Bria-IMT in combination with checkpoint inhibitors and is subject to ongoing investigation in a phase 3 randomized clinical trial in metastatic breast cancer.”

The phase 2 study included 54 patients with metastatic breast cancer who had received a median of six prior treatments. All patients were treated with the Bria-IMT regimen plus a checkpoint inhibitor. Of those, 37 received the same formulation now being used in BriaCell’s ongoing pivotal phase 3 trial for metastatic breast cancer. Median overall survival has not yet been finalized for some groups, as many patients remain alive. No treatment discontinuations related to Bria-IMT have been reported.

The Phase 3 Trial BRIA-ABC

The phase 3 study is comparing the Bria-IMT regimen plus a checkpoint inhibitor (Retifanlimab) with treatment of physician’s choice. Some patients will also receive the Bria-IMT regimen alone early in the trial; this group will close after 150 participants, and patients may be allowed to switch to the combination arm if needed.

The Bria-IMT regimen includes a vaccine-like therapy (SV-BR-1-GM) injected under the skin, low-dose chemotherapy (cyclophosphamide), interferon at injection sites and the checkpoint inhibitor. Treatment is given in three-week cycles and continues if working and well tolerated. Imaging is done every six weeks at first, then every eight weeks. The trial aims to enroll 404 participants across multiple sites.

To learn more visit ClinicalTrials.gov using the trial ID: NCT06072612.

Reference

“BriaCell Phase 2 Survival Achievement: 52% of Patients Surpass One-Year Milestone in Metastatic Breast Cancer.” News release. BriaCell Therapeutics Corp.

For more news on cancer updates, research and education, don’t forget to subscribe to CURE®’s newsletters here.