Pharmacokinetic drug interaction between fexofenadine and fluvastatin mediated by organic anion-transporting polypeptides in rats

This study aimed to examine the transporter-mediated drug interaction between fexofenadine and fluvastatin in rats. Compared to the control group given fluvastatin alone, the concurrent use of fexofenadine (10 or 20 mg/kg) prior to the oral administration of fluvastatin (5 mg/kg) decreased the systemic exposure of fluvastatin by 17-51% in rats. Consequently, the bioavailability of oral fluvastatin was significantly lower(p < 0.05) in the presence of fexofenadine compared to that from the control group. Furthermore, the intravenous pharmacokinetics of fluvastatin (2 mg/kg) was significantly altered by the pretreatment with fexofenadine (20 mg/kg, p.o.). The plasma clearance of fluvastatin was reduced by 44% in the presence of fexofenadine. The effect of fluvastatin on the pharmacokinetics of fexofenadine was also investigated in rats. The pretreatment with fluvastatin (5 or 10 mg/kg) decreased AUC and C-max of oral fexofenadine (10 mg/kg) by 47-53% and 28-60%, respectively, while it did not affect the intravenous pharmacokinetics of fexofenadine. Given that both fluvastatin and fexofenadine can interact with organic anion-transporting polypeptides (CATPs) expressed in intestine and liver, the present results suggest the potential drug interaction between fluvastatin and fexofenadine via the competition for the OATP-mediated cellular transport pathway during intestinal absorption and/or hepatic uptake of drugs. (C) 2009 Elsevier B.V. All rights reserved.