This randomized, multicenter, open label study will evaluate the safety and efficacy of
RO5083945 in combination with FOLFIRI as compared to FOLFIRI plus cetuximab or FOLFIRI alone
as second line treatment in patients with metastatic colorectal cancer. Patients will be
randomized to receive RO5083945 (1400 mg intravenously on Day 1 and Day 8 and every 2 weeks
thereafter) plus FOLFIRI standard iv chemotherapy or FOLFIRI plus cetuximab (400 mg/m2 iv on
Day 1 followed by 250 mg/m2 iv every week) or FOLFIRI alone. Anticipated time on study
treatment is until disease progression or unacceptable toxicity occurs.