Cetuximab given every 2 weeks plus irinotecan is an active and safe option for previously treated patients with metastatic colorectal cancer.

BACKGROUND: We gathered data from multiple institutions on the cetuximab regimen of patients with metastatic colorectal cancer. METHODS: 126 patients from 19 centers were included from July 2006 to July 2007 in this prospective non-controlled study. Irinotecan-refractory metastatic colorectal cancer patients with Karnofsky >or=70 received cetuximab 500 mg/m(2) every 2 weeks (q2w) in combination with irinotecan 180 mg/m(2) q2w until disease progression or unacceptable toxicity. The primary endpoint was the progression-free rate at 12 weeks. RESULTS: Median age was 65 years; 65.9% male; colon/rectum 64.3/34.1%; Karnofsky status or=90% in 45.3/54.7% of the patients. The progression-free rate was 42.7 (95% CI 32.8-52.6) and 22.4% (95% CI 14.2-30.7) at 12 and 24 weeks, respectively. The main grade 3 or 4 toxicities were: diarrhea 13.5% and acne-like rash 10.3%. No grade 3 or 4 infusional or allergic reactions were reported. CONCLUSIONS: The progression-free rates confirm that cetuximab q2w in combination with irinotecan is an option, and is as active and safe as the standard weekly regimen.