 This multi-center, open-label, non-randomized, non-placebo-controlled, Phase I study will define the safety profile and tumor response profile of the multi-kinase inhibitor BAY73-4506 as oral treatment in combination with the chemotherapy regimen mFOLFOX6 or FOLFIRI in patients with metastatic CRC. It will also determine the impact of the combined administration on the concentration of drugs over time pharmacokinetics of BAY73-4506, oxaliplatin, 5 FU, and irinotecan. 