RT Journal Article
SR Electronic
T1 Induction of P-Glycoprotein and Cytochrome P450 3A by HIV Protease Inhibitors
JF Drug Metabolism and Disposition
JO Drug Metab Dispos
FD American Society for Pharmacology and Experimental Therapeutics
SP 754
OP 760
VO 29
IS 5
A1 Liyue Huang
A1 Stephen A. Wring
A1 Joseph L. Woolley
A1 Kenneth R. Brouwer
A1 Cosette Serabjit-Singh
A1 Joseph W. Polli
YR 2001
UL http://dmd.aspetjournals.org/content/29/5/754.abstract
AB P-Glycoprotein (Pgp) and cytochrome P450 3A (CYP3A) are important enzymes affecting the disposition of HIV protease inhibitors (HIV PIs). After multiple dosing experiments in rats, decreases in the plasma concentrations and area under plasma concentration-time curve (AUC) for HIV PIs have been observed. The purpose of these studies was to determine the changes in Pgp and CYP3A expression and HIV PI plasma exposure after multiple doses of HIV PIs. Male rats were orally dosed with an amprenavir prodrug (450 mg/kg/day amprenavir-equivalent) or nelfinavir (175 mg/kg/day) for 1 or 14 days. Relative to day 1, theCmax and the AUC for amprenavir at day 14 were decreased by 33 and 51%, respectively. Similarly, the plasma concentration of nelfinavir at 1 h after the last dose (Cmax) was reduced by 52% after multiple doses. Compared with controls, dosing of amprenavir for 14 days increased intestinal Pgp and hepatic CYP3A protein levels by 59 and 151%, respectively, but did not alter intestinal CYP3A protein levels. In contrast, amprenavir treatment did not result in an increase in hepatic CYP3A activity. Nelfinavir treatment increased expression of intestinal Pgp and hepatic CYP3A levels by 83 and 85%, respectively, but not hepatic Pgp or intestinal CYP3A. HIV PIs also induced Pgp expression in the LS174T human intestinal cell line. These results indicate that HIV protease inhibitors induce both intestinal Pgp and hepatic CYP3A and suggest that induction of Pgp and CYP3A is a possible mechanism reducing drug exposure after multiple doses. The American Society for Pharmacology and Experimental Therapeutics