ArticleHigh-Performance Liquid Chromatographic Method for the Simultaneous Determination of the Six HIV-Protease Inhibitors and Two Non-Nucleoside Reverse Transcriptase Inhibitors in Human PlasmaTitier, Karine; Lagrange, Fabrice; Péhourcq, Fabienne; Edno-Mcheik, Leila; Moore, Nicholas; Molimard, Mathieu Author Information Department of Clinical Pharmacology and Toxicology, Pellegrin Hospital and University Victor Ségalen, Bordeaux, France Received July 18, 2001; accepted November 7, 2001. Address correspondence and reprint requests to Mathieu Molimard, Laboratoire de Pharmacologie Clinique et de Toxicologie, Hôpital Pellegrin, Place Amélie Raba-Léon, 33076 Bordeaux cedex, France; E-mail: [email protected] Therapeutic Drug Monitoring 24(3):p 417-424, June 2002. Buy Abstract A selective and sensitive high-performance liquid chromatographic (HPLC) method has been developed for the determination of the six human immunodeficiency virus (HIV)-protease inhibitors (amprenavir, indinavir, lopinavir, nelfinavir, ritonavir, and saquinavir) and the non-nucleoside reverse transcriptase inhibitors (efavirenz and nevirapine) in a single run. After a liquid–liquid extraction with diethyl ether, the six protease inhibitors and the two non-nucleoside reverse transcriptase inhibitors are separated on a Stability® RP18 column eluted with a gradient of acetonitrile and phosphate buffer 50 mmol/L pH 5.65. A sequential ultraviolet detection (5-minute sequence set at 240 nm for nevirapine acquisition, 22-minute sequence set at 215 nm for other antiretroviral drugs acquisition followed by a sequence set at 260 nm for internal standard acquisition) allowed for simultaneous quantitation of the six protease inhibitors, nevirapine, and efavirenz. Calibration curves were linear in the range 100 ng/mL to 10,000 ng/mL. The limit of quantitation was 50 ng/mL for all drugs except nevirapine (100 ng/mL). Average accuracy at four concentrations ranged from 88.2% to 110.9%. Both interday and intraday coefficients of variation were less than 11% for all drugs. The extraction recoveries were greater than 62%. This method is simple and shows a good specificity with respect to commonly co-prescribed drugs. This method allows accurate therapeutic monitoring of amprenavir, indinavir, lopinavir, nelfinavir, ritonavir, saquinavir, efavirenz, and nevirapine. © 2002 Lippincott Williams & Wilkins, Inc.