Colorectal cancer (CRC) is the second leading cause of cancer-related death globally. BRAF V600E mutations occur in approximately 12% of metastatic CRC (mCRC) patients, conferring an extremely poor prognosis with a median overall survival (OS) of only 11 months for standard chemotherapy. Most BRAF V600E-mutant mCRC are microsatellite stable (MSS) and do not benefit from single-agent PD-1/PD-L1 inhibition.
Preclinical and clinical evidence indicates that BRAF inhibition in combination with EGFR blockade can induce DNA damage, trigger a deficient mismatch repair (dMMR) phenotype, and increase tumor mutational burden (TMB), thereby sensitizing MSS tumors to immune checkpoint inhibition. This provides a strong rationale for combining BRAF/EGFR inhibitors with anti-PD-1 and anti-CTLA-4 immunotherapy.
This is a single-arm, open-label, Phase II clinical trial. The primary objective is to evaluate the efficacy and safety of the triplet combination of sintilimab (anti-PD-1), ipilimumab N01 (anti-CTLA-4), cetuximab (anti-EGFR), and dabrafenib (BRAF inhibitor) in patients with MSS, BRAF V600E-mutant mCRC.
Provided written informed consent.
Age ≥ 18 years.
Histologically or pathologically confirmed colorectal adenocarcinoma.
Documented microsatellite stable (MSS) and BRAF V600E mutation by prior genomic testing.
Received any approved or investigational systemic anti-tumor therapy within 4 weeks prior to enrollment.
Underwent any surgery or invasive procedure within 4 weeks prior to study initiation (exceptions include venous catheter placement and paracentesis/drainage).
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).
Presence of severe comorbidities or serious medical conditions.