The FDA granted fast‑track designation to pelareorep (Reolysin) in combination with bevacizumab and FOLFIRI for second‑line treatment of KRAS‑mutant, microsatellite‑stable metastatic colorectal cancer. Sponsor Oncolytics Biotech pointed to response and survival signals from early studies—an objective response rate reported at 33% in a dose‑escalation cohort and a median progression‑free survival of 16.6 months—as the basis for expedited review. Oncolytics positions pelareorep as an oncolytic virus platform that combines direct tumor lysis with immune stimulation to convert immune‑excluded tumors into responders to checkpoint blockade. FDA fast‑track status aims to accelerate development timelines in an underserved patient population. The company said it will continue clinical work to validate signals in randomized settings and to define biomarker strategies for patient selection.