Low nevirapine plasma concentrations predict virological failure in an unselected HIV-1-infected population.
OBJECTIVE
To assess the relationship between plasma nevirapine concentrations and plasma HIV-1 RNA response in HIV-1-infected patients.


METHODS
An observational cohort analysis.


METHODS
Plasma samples were obtained on a routine basis from 189 patients receiving nevirapine 200mg twice daily, and plasma nevirapine concentrations were measured with reversed phase high performance liquid chromatography. Patients were divided into two groups based on plasma nevirapine concentrations below (and equal to) or above 3 mg/L. The association between steady-state nevirapine concentrations and plasma HIV-1 RNA was determined by multivariate analysis.


RESULTS
Out of 189 patients, 13 (7%) had low nevirapine plasma concentrations and 176 patients had concentrations above 3 mg/L. In total, 22 (12%) patients showed virological failure and 8 patients (4%) discontinued nevirapine because of adverse effects. The risk of failure in patients with nevirapine plasma concentrations </=3mg/L was increased (relative risk 5.0, 95% CI 1.8-13.7). Rashes and liver enzyme elevations each occurred in 8% of patients.


CONCLUSIONS
Low nevirapine drug concentrations are predictive of virological failure.
de Vries-Sluijs
Theodora E M S
TE
Department of Internal Medicine, University Hospital Rotterdam, Dijkzigt, Rotterdam, The Netherlands.
Dieleman
Jeanne P
JP
Arts
Dennis
D
Huitema
Alwin D R
AD
Beijnen
Jos H
JH
Schutten
Martin
M
van der Ende
Marchina E
ME
D000328:Adult; D015331:Cohort Studies; D005260:Female; D015658:HIV Infections / Q000097:blood / Q000188:drug therapy*; D015497:HIV-1 / Q000187:drug effects*; D006716:Homosexuality; D006801:Humans; D008297:Male; D019829:Nevirapine / Q000097:blood* / Q000627:therapeutic use*; D018894:Reverse Transcriptase Inhibitors / Q000097:blood* / Q000627:therapeutic use*; D012307:Risk Factors
D018894:Reverse Transcriptase Inhibitors; D019829:Nevirapine