In vitro cell killing proficiency of autologous immune cells educated with allogenic multi-cancer tumor cell lysate.

Abstract

e14675 Background: Allogenic tumor lysate therapies offer a novel approach in oncology, to initiate a measured immune system response to combat cancer. Loaded with tumor antigens, these lysates stimulate the patient's immune system for targeted cancer cell destruction. In vitro data suggesting efficacy is pivotal prior to clinical trials. Per-C-Vax is a novel, organ-agnostic, allogenic tumor lysate immuno-stimulant, and is intended to target solid organ malignancies via subcutaneous injection. It is derived from a multi-organ cell-line cocktail, which has been induced into apoptosis to capture diverse Tumor Associated Molecular Patterns (TAMPs) and Damage Associated Molecular Patterns (DAMPs). Our study assesses Per-C-Vax-educated patient-specific immunocytes' in-vitro cell-killing activity against their autologous tumor cells. Methods: We collected simultaneous blood and tumor tissue samples from 22 patients with solid organ tumors under approved protocols. The cohort included 10 head and neck (45%), 4 breast (18%), and 8 other cancers (36%) comprising colorectal, ovary, lung, gallbladder, prostate, uterine, cervix, and gastric cancers. Peripheral Blood Mononuclear Cells (PBMCs) from a 10 ml venous draw were split into control and Per-C-Vax incubated aliquots for each patient. Approximately 1,000 tumor cells, stained with Calcein AM, were co-cultured with about 20,000 cells from each of the Per-C-Vax and control PBMC aliquots (autologous). Imaging-based pre- and post-co-culture counts determined the cell-kill rate for each aliquot. Results: PBMCs not treated with Per C Vax showed a significantly reduced cancer cell killing activity against autologous tumor cells compared to Per-C-Vax -treated PBMCs, suggesting the tolerogenic characteristic of immunocytes to the malignancy (0%-32%, 95% CI 10.16 to 16.65). On the other hand, PBMCs treated with Per-C-Vax showed significant cell-kill activity ranging from 46% to 84% in head and neck (mean 62.1%, 95% CI 52.67 to 71.53), 51% to 73% in breast (mean 62%, 95% CI 44.33 to 79.67), 38% to 87% in other cancers (colorectal, ovary, lung, gallbladder, prostate, uterine, cervix, gastric) (mean 50.87%, 95% CI 37.71 to 64.04). A comparative analysis between the untreated group and the group treated with Per-C-Vax revealed a statistically significant result with a p-value <0.005. Conclusions: Patient-specific PBMCs incubated with Per-C-Vax tumor lysate immuno-stimulant show significant autologous cancer cell killing activity against multiple cancers in vitro. Human trials to establish safety and efficacy are planned.