An Open and Exploratory Phase Ⅱ Clinical Trial of Cadonilimab Combined With Anti-angiogenic Agents in Metastatic dMMR/MSI-H Colorectal Cancer
This study is a prospective, open-label, dual-arm exploratory Phase II clinical trial designed to assess the efficacy and safety of cadonilimab combined with anti-angiogenic agents in patients with dMMR/MSI-H recurrent or metastatic colorectal cancer. Eligible patients are enrolled into two cohorts based on their prior exposure to PD-1/PD-L1 antibody therapy: Cohort A (immune-naive group - patients with no prior PD-1/PD-L1 treatment) and Cohort B (immune rechallenge group - patients who previously received and failed PD-1/PD-L1 therapy). All participants receive combination therapy with cadonilimab and an anti-angiogenic agent, which is selected by the investigator from bevacizumab, regorafenib, or fruquintinib. Treatment continues until the occurrence of intolerable toxicity, disease progression, withdrawal of informed consent, loss to follow-up, death, other conditions deemed by the investigator to warrant discontinuation, or study termination-whichever occurs first. Cadonilimab treatment will not exceed two years. Tumor response is evaluated every six weeks using RECIST v1.1 criteria. Safety is assessed using CTCAE v5.0, and adverse events are recorded from the first dose to 30 days after the end of treatment.
• \- Signed written informed consent prior to enrollment. Age 18-80 years. dMMR or MSI-H Diagnosis confirmed by histological examination and/or cytological examination combined with imaging assessment of advanced colorectal cancer.
• ECOG score: 0 to 2. At least one measurable lesion (≥10 mm long diameter on CT scan for non-lymph node lesions and ≥15 mm short diameter on CT scan for lymph node lesions according to iRECIST criteria).
• Adequate organ function with. Routine blood: Absolute Neutrophil Count (ANC) 1.5 × 109/L, Platelets (Platelet, PLT) ≥ 100 × 109/L, Hemoglobin (HGB) ≥ 90 g/L.
• Liver function: Total Bilirubin (TBIL) ≤ 1.5 × Upper Limit of Normal Value (ULN); Alanine Aminotransferase (ALT) and Aspartate Transferase (AST) ≤3×ULN; serum albumin ≥30 g/L; after conventional hepatoprotective treatment meeting the above criteria, and can be stable for at least 1 week after evaluation by the investigator can be enrolled.
• Renal function: Creatinine (Cr) ≤ 1.5 × ULN, or creatinine clearance ≥ 50 mL/mi (applying the standard Cockcroft-Gault formula).
• Coagulation function: International Normalized Ratio (INR) ≤ 1.5 /PT ≤ 1.5 × ULN, aPTT ≤ 1.5 × ULN; if the subject is receiving anticoagulation therapy, as long as PT and INR are within the range drawn up by anticoagulant drugs.
• A predicted survival of ≥ 3 months. Female patients must be non-pregnant and non-lactating and are required to use a medically approved form of contraception (e.g., IUD, pill or condom) during study treatment and for at least 120 days after study completion, and are not allowed to donate eggs to another person or freeze them for fertilization and propagation during this period.