Pharmacokinetic interaction involving sorafenib and the calcium-channel blocker felodipine in a patient with hepatocellular carcinoma.

Sorafenib, an orally active multi-kinase inhibitor approved for the treatment of hepatocellular carcinoma (HCC), is primarily metabolized both via cytochrome P450 3A4 isoform (CYP3A4) and UGT1A9. Due to the contribution of these two biotransformation pathways, sorafenib is considered to be less susceptible than other agents to CYP3A4 drug-drug interactions. This report discusses a clinically relevant pharmacokinetic CYP3A4 drug-drug interaction between sorafenib and felodipine in an 80-year-old Caucasian patient with HCC.