The Efficacy and Safety of IBI351, Cetuximab β Combined With FOLFIRI as First-line /IBI351, Cetuximab β as Second-line in the Treatment of KRAS G12C-mutated Metastatic Colorectal Cancer

This is an open-label, multicenter, single-arm Phase II clinical study, divided into subgroups A and B: Cohort A - To evaluate the efficacy and safety of IBI351, cetuximab β combined with FOLFIRI as first-line treatment for metastatic colorectal cancer with KRAS G12C mutations; Twenty untreated patients with advanced colorectal cancer with KRAS G12C mutation are proposed to be enrolled and treated with the first-line IBI351+ cetuximab β injection +FOLFIRI regimen. The historical reference is expected to be around 40-50%, and it is expected to increase to around 75%. Therefore, among the 20 patients, if ≥15 patients achieve remission, it is considered that the efficacy of the trial protocol is statistically significant. Cohort B - To evaluate the efficacy and safety of BI351 and cetuximab β as second-line treatment for metastatic colorectal cancer with KRAS G12C mutations. It is proposed to enrolled 30 patients with advanced colorectal cancer with KRAS G12C mutation who have progressed after first-line treatment, and evaluate IBI351+ cetuximab β injection for second-line treatment. The historical reference is around 25%, and it is expected to increase to around 50%. Therefore, among the 30 patients, if ≥15 patients achieve remission, it is considered that the efficacy of the trial protocol is statistically significant. Imaging assessment of tumor remission was conducted every 8 weeks until disease progression. The period from the start of treatment to disease progression is defined as PFS. The safety observation indicators include: the incidence and severity of adverse events (AE) and serious adverse events (SAE); Laboratory tests, vital signs, physical examinations, and changes in electrocardiogram (ECG). Record the subsequent tumor treatment and survival follow-up after the progression. Definition of study conclusion: The study will conclude after the last subject has been treated for 2 years or has completed the treatment (whichever occurs first).

NCT Number	NCT06959589
Lead Sponsor	Second Affiliated Hospital, School of Medicine, Zhejiang University
Conditions	Colorectal Cancer Metastatic, KRAS G12C Mutation
Enrollment	50 participants
Start Date	2025-05-22
Primary Completion	2027-05-31 (estimated)
Study Completion	2028-12-31 (estimated)
Updated on ClinicalTrials.gov	2026-05-11