SIMULTANEOUS DETERMINATION OF RITONAVIR AND SAQUINAVIR, 2 HUMAN-IMMUNODEFICIENCY-VIRUS PROTEASE INHIBITORS, IN HUMAN SERUM BY HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHY

The aim of this study was to describe an high-performance liquid chrom atographic assay for the simultaneous determination of two HN protease inhibitors, saquinavir and ritonavir, in human serum. The method invo lved extraction of ritonavir and saquinavir from serum with the aid of solid-phase extraction C-18 cartridges followed by high-performance l iquid chromatography with a C-8 column and ultraviolet detection set a t a wavelength of 240 nm. The assay was linear and has been validated over the concentrations range of 0.5-32 mu g/ml for ritonavir and 0.07 5-4.8 mu g/ml for saquinavir, from 600 mu l serum extracted. In future , the assay will be used to support human population pharmacokinetic s tudies, and therapeutic drug monitoring for ritonavir and saquinavir. (C) 1998 Elsevier Science B.V. All rights reserved.