petosemtamab + FOLFOX

**petosemtamab + FOLFOX** is a combination therapy under clinical investigation for advanced solid tumors, especially metastatic colorectal cancer. Petosemtamab (MCLA-158) is a bispecific monoclonal antibody that targets both Epidermal growth factor receptor (EGFR) and Leucine-rich repeat-containing G-protein coupled receptor 5 (LGR5), designed to inhibit EGFR-dependent tumor growth and stemness in cancer cells. FOLFOX is an established chemotherapy regimen consisting of folinic acid (leucovorin), fluorouracil (5-FU), and oxaliplatin, primarily used to induce cytotoxicity in rapidly dividing tumor cells. This combination is being tested—most notably in Phase 1/2 clinical trials—for its tolerability and anti-tumor activity in patients with metastatic colorectal cancer (mCRC) who previously received certain chemotherapy regimens. Petosemtamab is developed by Merus, and FOLFOX is a generic regimen with no single developer. The combination leverages targeted inhibition of EGFR/LGR5 and standard chemotherapeutic cytotoxicity.