Treatment sequence with either irinotecan/cetuximab followed by FOLFOX-4 or the reverse strategy in metastatic colorectal cancer patients progressing after first-line FOLFIRI/bevacizumab: An Italian Group for the Study of Gastrointestinal Cancer phase III, randomised trial comparing two sequences of therapy in colorectal metastatic patients

Introduction The optimal treatment strategy for RAS wild type (WT) mCRC is controversial. Our phase III study investigated the effect of introducing earlier (second-line) or later (third-line) cetuximab in patients progressed after FOLFIRI/bevacizumab first-line. Patients and methods mCRC patients progressing after FOLFIRI/bevacizumab first-line were randomised to receive second-line irinotecan/cetuximab followed by third-line FOLFOX-4 (arm A) or the reverse sequence (arm B). Primary end-point was progression-free survival (PFS). Results About 54 and 56 patients were randomised in arm A and in arm B, respectively. After a median follow-up of 37.5 months, 100 PFS events were recorded. Median PFS was 9.9 months in arm A and 11.3 months in arm B (Hazard ratio [HR] 1.04, 95% confidence interval [CI]: 0.69–1.56, p = 0.854), while median overall survival was 12.3 months in arm A and 18.6 months in arm B (HR 0.84, 95% CI: 0.55–1.28; p = 0.411). No overall difference in side-effects were observed between the two treatment arms. Conclusions This trial did not meet the primary end-point (PFS). Like other preclinical and clinical evidences, our study seems to suggest a reduced activity of cetuximab after a first-line bevacizumab-based therapy.