BriaCell Therapeutics Corp. announced new data highlighting the ability of its Bria-IMT™ regimen, when combined with immune checkpoint inhibitors (CPI), to increase the infiltration of cancer-fighting CD8+ T cells into metastatic breast cancer tumors and lymph nodes. The findings, presented in a poster at the 2024 San Antonio Breast Cancer Symposium (SABCS), suggest the regimen can convert immunologically 'cold' tumors into 'hot' tumors, making them more susceptible to immune-mediated destruction.
The study utilized CD8 ImmunoPET imaging, a precision diagnostic tool, to monitor patients' immune system responses in a phase 2 trial. The results indicated that the Bria-IMT™ regimen effectively induced tumor infiltration with CD8+ 'killer' T cells. This infiltration correlated with a marked reduction in tumor markers in some patients, suggesting clinical benefit.
Key Findings from the Study
The poster presentation (Abstract Number: SESS-1069, Presentation ID: P5-10-12) detailed the following observations in six patients with metastatic breast cancer treated with Bria-IMT™ plus CPI after a median of 7 prior treatments:
- The treatment was generally well-tolerated.
- Two patients who had cold tumors turn hot experienced a reduction in tumor markers.
- 50% of patients (3 out of 6) showed a decrease in neutrophil/lymphocyte ratio (NLR) at cycle 2 compared to baseline, suggesting immune system activation.
- Evidence of 'cold' tumors and lymph nodes becoming 'hot' indicated immune system activation.
ImmunoPET Imaging and Clinical Correlation
CD8 ImmunoPET imaging, which marks CD8+ T-cells crucial for cancer cell detection and destruction, revealed that Bria-IMT™ plus CPI led to the infiltration of these cells into metastatic tumors and lymphoid tissue. This infiltration resulted in the destruction of cancer cells, effectively turning 'cold' tumors and lymph nodes 'hot' on ImmunoPET imaging.
"We are excited to successfully utilize innovative technology such as CD8 ImmunoPET imaging to gain insight into the mechanism of action and potential strength of the BriaCell immunotherapy program," stated Russ Kuker, MD, Associate Professor of Clinical Radiology at the University of Miami Miller School of Medicine and author of the poster.
Implications for Future Research
The findings suggest that advanced ImmunoPET imaging correlates with clinical benefit when using the Bria-IMT™ combination regimen in metastatic breast cancer. It also proposes the potential use of this imaging technique in identifying immunotherapy-responsive tumors. These results support the continued evaluation of the Bria-IMT™ combination regimen in BriaCell’s ongoing pivotal Phase 3 study (NCT06072612) in metastatic breast cancer.
"By employing more accurate precision imaging techniques, we have been able to document the mechanism of action of the Bria-IMT™ regimen as we progress this therapy to revolutionize the way we treat cancer patients and improve patient outcomes," noted Giuseppe Del Priore, MD, MPH, BriaCell’s Chief Medical Officer.
