Combination Immunotherapy in Colorectal Cancer

This is a pilot study to see whether a combination of two investigational drugs that target the immune system can be given to people with colorectal cancer before surgically removing the tumor. This study is also being done to see what side effects this combination of drugs has and what effect they have on colorectal cancer. The two monoclonal antibodies are balstilimab, a programmed cell death protein 1 (PD-1) inhibitor, and botensilimab, a cytotoxic T lymphocyte-associated protein 4 (CTLA-4) inhibitor. Participants will receive a dose of balstilimab and botensilimab, both given intravenously (IV), followed by a second dose of balstilimab approximately 2 weeks after the first dose. Both doses of balstilimab and the single dose of botensilimab will be given during an 8 weeks period before surgery.