Race is not associated with nevirapine pharmacokinetics

The effect of race on the pharmacokinetics of nevirapine was investigated in a nonselected population. Included patients were ambulatory HIV-1-infected patients from the outpatient clinics of the Academic Medical Center and the Slotervaart Hospital, Amsterdam, The Netherlands. All patients were using nevirapine as part of their antiretroviral regimen and had at least one plasma concentration available for analysis. From the included patients, gender, age, race, hepatitis C status, baseline ASAT value, and body weight were obtained. The nonlinear mixed-effect modeling program (NONMEM) version V 1.1 was used for all analyses. Population pharmacokinetic parameters [clearance (CL/F), volume of distribution (V/F), absorption rate constant (ka)] and interindividual (IIV) and interoccasion variability (IOV) were estimated. The influence of race on the CL/F of nevirapine was tested as Negroid race versus the other races, Asian race versus the other races, and the Negroid and the Asian races as separate variables versus the Caucasian race. A database of 1732 nevirapine plasma concentrations of 383 HIV-1-infected individuals collected during 1186 outpatient clinic visits was available for this analysis. The conclusion of this study is that race is not associated with the pharmacokinetics of nevirapine, and thus requires no dose adaptations.