Cytochrome P450 3A Inhibition by Atazanavir and Ritonavir, but Not Demography or Drug Formulation, Influences Saquinavir Population Pharmacokinetics in Human Immunodeficiency Virus Type 1-Infected Adults▿

摘要

Inadequate concentrations of the human immunodeficiency virus (HIV) protease inhibitor saquinavir jeopardize individual therapy success or produce side effects despite treatment according to the current guidelines. We performed a population pharmacokinetic analysis with NONMEM and determined that the steady-state pharmacokinetics of saquinavir in 136 HIV type 1-infected adults was modulated by a decrease in saquinavir CL following coadministration of the cytochrome P450 3A inhibitors ritonavir and atazanavir. In contrast, age, sex, weight, pregnancy, and the pharmaceutical formulation exerted only minor, nonsignificant effects.