Encorafenib, Cetuximab, and Nivolumab in Treating Patients With Microsatellite Stable, BRAFV600E Mutated Unresectable or Metastatic Colorectal Cancer

This phase I/II trial studies the best dose and side effects of encorafenib, cetuximab, and nivolumab and how well they work together in treating patients with microsatellite stable, BRAFV600E gene mutated colorectal cancer that cannot be removed by surgery (unresectable) or has spread to other places in the body (metastatic). Encorafenib and cetuximab may stop the growth of tumor cells by blocking some of the enzymes needed for cell growth. Immunotherapy with monoclonal antibodies, such as nivolumab, may help the body’s immune system attack the cancer, and may interfere with the ability of tumor cells to grow and spread.Giving encorafenib, cetuximab, and nivolumab may work better in treating patients with colorectal cancer compared to cetuximab alone.