Phase II Study of Anti-PD-1/VEGF Bispecific Antibody Ivonescimab in Patients With Previously Treated Metastatic Colorectal Cancer

Primary Objective: • To evaluate the efficacy of ivonescimab, as determined by the objective response rate per iRECIST, in three distinct cohorts of patients with treatment-refractory metastatic colorectal cancer: 1) dMMR/MSI-H refractory to anti-PD-1 therapy, 2) pMMR/MSS without liver metastases, and 3) pMMR/MSS with liver metastases. Secondary Objective: * To evaluate the safety of ivonescimab in patients with metastatic colorectal cancer. * To evaluate the efficacy of ivonescimab, as determined by the objective response rate per RECIST 1.1, in three distinct cohorts of patients with treatment-refractory metastatic colorectal cancer: 1) dMMR/MSI-H refractory to anti-PD-1 therapy, 2) pMMR/non-MSI-H without liver metastases, and 3) pMMR/non-MSI-H with liver metastases. * To evaluate changes in intratumoral CD8+ T cell density following ivonescimab therapy. Exploratory Objectives: * To assess the time to response following treatment with ivonescimab in patients with metastatic colorectal cancer. * To assess the durability of response following treatment with ivonescimab in patients with metastatic colorectal cancer. * To evaluate progression-free survival following treatment with ivonescimab in patients with metastatic colorectal cancer. * To evaluate overall survival following treatment with ivonescimab in patients with metastatic colorectal cancer. * To investigate clinical, pathologic, and molecular features associated with therapeutic response to ivonescimab in patients with metastatic colorectal cancer. * To investigate changes in immune cell composition and distance relationships within the metastatic CRC tumor microenvironment following ivonescimab therapy. * To evaluate changes in peripheral immune cell populations in metastatic CRC patients following ivonescimab therapy.