AK112 Plus FOLFIRI Versus Bevacizumab Plus FOLFIRI as Second-line Treatment of MSS/pMMR Metastatic Colorectal Cancer

After obtaining informed consent, the experimental group receives AK112 at 20 mg/kg via intravenous infusion on day 1 of each cycle (Q2W) combined with FOLFIRI chemotherapy (Q2W), while the control group receives bevacizumab at 5 mg/kg via intravenous infusion on day 1 of each cycle (Q2W) in combination with FOLFIRI (Q2W). Treatment continues until disease progression, death, intolerable toxicity, withdrawal of consent, initiation of new antitumor therapy, or other protocol-specified reasons for discontinuation. The maximum treatment duration is 24 months.