Article

Chronic administration of nevirapine during pregnancy: impact of pregnancy on pharmacokinetics

San Diego Schools of Medicine and Pharmacy and Pharmaceutical Sciences, University of California, San Diego, CA 92103, USA.
HIV Medicine (Impact Factor: 3.45). 05/2008; 9(4):214-20. DOI: 10.1111/j.1468-1293.2008.00553.x
Source: PubMed

ABSTRACT To determine the impact of pregnancy on the pharmacokinetics (PK) of nevirapine (NVP) during chronic dosing in HIV-infected women and appropriate NVP dosing in this population.
Twenty-six pregnant women participating in two open-label Pediatric AIDS Clinical Trials Group studies (P1022 and P1026S) were evaluated. Each patient received 200 mg NVP every 12 h and had PK evaluations during the second or third trimester; these evaluations were repeated postpartum. Paired maternal and cord blood NVP concentrations were collected at delivery in nine patients. Ante- and postpartum comparisons were made using paired t-tests and using a 'bioequivalence' approach to determine confidence interval (CI).
The average NVP Area Under the Curve (AUC) was 56 +/- 13 mcg(*)h/mL antepartum and 61 +/- 15 mcg(*)h/mL postpartum. The typical parameters +/- standard error were apparent clearance (CL/F)=3.51 +/- 0.18 L/h and apparent volume of distribution (Vd/F)=121 +/- 19.8 L. There were no significant differences between antepartum and postpartum AUC or pre-dose concentrations. The AUC ratio was 0.90 with a 90% CI of the mean equal to 0.80-1.02. The median (+/- standard deviation) cord blood to maternal NVP concentration ratio was 0.91 +/- 0.90.
Pregnancy does not alter NVP PK and the standard dose (200 mg every 12 h) is appropriate during pregnancy.

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