Oncolytics Biotech reported positive preclinical results for pelareorep combined with a pan-RAS inhibitor in a RAS-driven colorectal cancer model. During an initial treatment period using every-other-day pelareorep dosing, pelareorep alone, the RAS inhibitor alone and the combination all reduced tumor growth versus control, with the largest reductions in the inhibitor and combination groups. The results showed pelareorep activity was maintained alongside RAS inhibition, with no evidence that the therapies antagonized each other. Its incremental benefit became less apparent after dosing shifted to once weekly. The company said the findings support further studies of optimized schedules and the possibility that sustained pelareorep activity could deepen or prolong responses and delay resistance to RAS-targeted therapy. Oncolytics plans to test additional schedules and RAS-driven tumor models. Pelareorep is an intravenous investigational immunotherapy designed to replicate selectively in tumor cells while activating innate and adaptive immune responses.