Pharmacogenetic interactions of efavirenz or rifampin and isoniazid with levonorgestrel emergency contraception during treatment of HIV or tuberculosis.

ABSTRACT:

Objective

In AIDS Clinical Trials Group study A5375, a pharmacokinetic trial of levonorgestrel emergency contraception, double-dose levonorgestrel (3 mg, versus standard dose 1.5 mg) offset the induction effects of efavirenz or rifampin on plasma levonorgestrel exposure over 8 h post-dose (AUC 0-8h ). We characterized the pharmacogenetics of these interactions.

Methods

Cisgender women receiving efavirenz- or dolutegravir-based HIV therapy, or on isoniazid-rifampin for tuberculosis, were followed after a single oral dose of levonorgestrel. Linear regression models, adjusted for BMI and age, characterized associations of CYP2B6 and NAT2 genotypes (which affect plasma efavirenz and isoniazid exposure, respectively) with levonorgestrel pharmacokinetic parameters.

Results

SUBMITTER: Agyemang N 

PROVIDER: S-EPMC10309098 | biostudies-literature | 2023 Aug

REPOSITORIES: biostudies-literature