Researchers from Creatv Bio, Division of Creatv MicroTech, Inc. (Monmouth Junction, NJ) and The Mayo Clinic (Jacksonville, FL), in collaboration with BriaCell Therapeutics Corporation (Philadelphia, PA), have shown in a study of Metastatic Breast Cancer (mBC) patients treated with SV-BR-1-GM vaccine in combination with an immunotherapy drug, that the vaccine can change the PD-L1 expression of the tumor. The PD-L1 expression is determined by the LifeTracDx® blood test, which captures Circulating Tumor Cells (CTCs) and Cancer Associated Macrophage-Like cells (CAMLs) by staining the cells for PD-L1 marker.
The data was presented at the annual San Antonio Breast Cancer Symposium (SABCS) in December 2024, and is titled: PD-L1 Upregulation in Circulating Tumor Associated Cells Predicts for Clinical Outcomes in a Phase 1/2 Clinical Trial Using SV-BR-1-GM Vaccine with the Check Point Inhibitor Retifanlimab in Metastatic Breast Cancer Patients, an Interim Analysis. https://creatvbio.com/posters.
The data of 36 patients showed that a decrease in CTCs/CAMLs numbers significantly correlated with better Progression Free Survival and trended for better Overall Survival. In addition, SV-BR-1_GM therapy appeared to upregulate PD-L1 expression in 15 patients which correlated with better responses to combination treatment with the anti-PD-L1 check point inhibitor.
LifeTracDx® can predict treatment response, and at the same time provide information about companion diagnostics for a wide variety of tumor markers. The test isolates CAMLs and CTCs from the blood of the cancer patient. CAMLs are macrophages that have engulfed tumor cells from tumor site. Thus, both CAMLs and CTCs contain tumor material, ideal for companion diagnostic.
