Initial therapy with FOLFOX-4 plus panitumumab followed by maintenance therapy with 5-FU/LV plus panitumumab or single-agent panitumumab in patients with metastatic colorectal cancer and absence of mutations of RAS genes.

Primary objectives: To compare the efficacy, in terms of non-inferiority of progression-free survival (PFS), of maintenance with panitumumab alone (arm B) as compared to panitumumab with 5-FU/LV (arm A) following induction treatment with FOLFOX-4 and panitumumab.