FOLFIRI and Bevacizumab With or Without Pelareorep for Second-Line Treatment of Metastatic RAS-Mutated, Microsatellite-Stable Colorectal Cancer

Inclusion Criteria: * Histologically confirmed cancer of the colon or rectum with documented metastasis * Measurable disease per RECIST v. 1.1 * Not candidates for curative surgery or curative radiation * Progressed on, or been intolerant to, a first-line, oxaliplatin-based chemotherapy regimen in the metastatic setting or relapsed within 6 months of completing adjuvant oxaliplatin * Considered medically eligible to receive standard of care (SOC) FOLFIRI with bevacizumab * Non-microsatellite instability high or non-deficient mismatch repair (non-MSI-H/non dMMR) tumor status per a standard local testing method * Tumor confirmed to harbor a known RAS mutation per a standard local testing method * ECOG performance status of 0 or 1 * Patients must have adequate hematological, renal, and hepatic function * Female patients of childbearing potential must have a negative pregnancy test * Life expectancy of at least 6 months Exclusion Criteria: * Undergone systemic chemotherapy, radiotherapy, or surgery, \<4 weeks before study treatment * Ongoing AEs of Grade ≥2 that are related to anti-cancer treatment * Prior treatment with irinotecan * Symptomatic brain metastases * Active autoimmune disease * Receiving immunosuppressive or myelosuppressive medications * Active, uncontrolled infections * Known HIV infection or active hepatitis B or C that requires anti-viral treatment * History of another primary cancer within the last 3 years except for non-melanoma skin cancer, early-stage prostate cancer, or curatively treated cervical carcinoma in-situ * History of allergy or known hypersensitivity to any of the study drugs, study drug classes, * Uncontrolled or severe cardiac disease * Received any vaccine within 28 days prior to first study treatment