A Phase II Study of Sintilimab Combined With Ipilimumab N01, Cetuximab and Dabrafenib in Patients With Microsatellite-Stable, BRAF V600E-Mutated Metastatic Colorectal Cancer

Inclusion Criteria: 1. Provided written informed consent. 2. Age ≥ 18 years. 3. Histologically or pathologically confirmed colorectal adenocarcinoma. 4. Documented microsatellite stable (MSS) and BRAF V600E mutation by prior genomic testing. 5. Locally advanced unresectable disease or distant metastasis. 6. No prior treatment with BRAF/MEK/ERK inhibitors, EGFR inhibitors, or immune checkpoint inhibitors (ICI). 7. Presence of measurable target lesions per RECIST 1.1. 8. Eastern Cooperative Oncology Group (ECOG) performance status (PS) score of 0 or 1. 9. Adequate organ function, based on the following laboratory values obtained within 7 days prior to Cycle 1 Day 1: 1. Hemoglobin ≥ 9.0 g/dL. 2. Absolute neutrophil count ≥ 1,500/mm³ (≥ 1.5 × 109/L). 3. Platelet count ≥ 80,000/mm³ (≥ 80 × 109/L). 4. Serum total bilirubin ≤ 1.5 × upper limit of normal (ULN). 5. Aspartate aminotransferase (AST) and alanine aminotransferase (ALT) ≤ 2.5 × ULN. 6. Serum creatinine ≤ 1.5 × ULN or creatinine clearance ≥ 50 mL/min. 10. Willing and able to comply with study procedures and visit schedule. Exclusion Criteria: 1. Received any approved or investigational systemic anti-tumor therapy within 4 weeks prior to enrollment. 2. Underwent any surgery or invasive procedure within 4 weeks prior to study initiation (exceptions include venous catheter placement and paracentesis/drainage). 3. Multiple primary malignancies (exceptions include completely resected basal cell carcinoma, stage I squamous cell carcinoma, carcinoma in situ, intramucosal carcinoma, superficial bladder cancer, or any other cancer that has been in complete remission for at least 3 years). 4. Presence of severe comorbidities or serious medical conditions. 5. Pregnant or breastfeeding females. 6. The investigator deems the patient unsuitable for participation in this study.