RecruitingPhase 2Drug trialICE Study: Combination of Irinotecan Plus Cetuximab and Envafolimab as a Rechallenge Regimen in mCRCThis is a non-profit phase II, open, clinical study of the combination of irinotecan plus cetuximab and envafolimab as a rechallenge regimen, in pre-treated RAS/BRAF wild type metastatic colorectal cancer patients (according to liquid biopsy at baseline). Patients have been treated in front lines with irinotecan and cetuximab and had a clinical benefit (complete or partial response) from both of them, no matter whether they had treated by any PD-1 inhibitor before.