Effect of P-glycoprotein and breast cancer resistance protein inhibition on the pharmacokinetics of sunitinib in rats.

The aim of this study was to elucidate the roles of P-glycoprotein (P-gp/ABCB1) and breast cancer resistance protein (BCRP/ABCG2) in the plasma concentration, biliary excretion, and distribution to the liver, kidney, and brain of sunitinib. The pharmacokinetics of sunitinib was examined in rats treated with PSC833 (valspodar) and pantoprazole, potent inhibitors of P-gp and BCRP, respectively. The sunitinib concentrations in plasma, bile, liver, kidney, and brain were determined by liquid chromatography-tandem mass spectrometry.