Efavirenz and rifampicin in the South African context: is there a need to dose-increase efavirenz with concurrent rifampicin therapy?

ABSTRACT:

Background

Increasing efavirenz (EFV) dose from 600 mg to 800 mg daily has been suggested with concomitant rifampicin (RFN), as induction of cytochrome P450 isoenzymes may reduce EFV plasma concentrations.

Methods

Individuals from the CIPRA-South Africa cohort taking EFV-based antiretroviral therapy with concomitant tuberculosis (TB) were dosed with either increased (800 mg) or standard (600 mg) dose EFV during TB treatment. After TB therapy, all individuals took 600 mg EFV. Two mid-dosing interval EFV concentrations were determined from each individual: after 4 weeks of concomitant EFV and RFN therapy, and ≥4 weeks after TB therapy completion. Mid-dosing interval EFV concentrations were compared within individuals using the Wilcoxon signed-rank test.

Results

Paired s

SUBMITTER: Orrell C 

PROVIDER: S-EPMC3145153 | biostudies-literature | 2011

REPOSITORIES: biostudies-literature