The Effect of CYP2B6 Genotype on the Clearance and Autoinduction of Efavirenz in Healthy Subjects and the Subsequent Impact on Efavirenz Exposure

Presented at ACoP 2024. Efavirenz is metabolized primarily by CYP2B6, to form 8-OH EFV, and also by CYP2A6, to form 7-OH EFV. Upon chronic administration, efavirenz induces both CYP2B6 and CYP2A6, leading to autoinduction of its metabolism. A population pharmacokinetic model was constructed to quantify the impact of CYP2B6 phenotype on efavirenz autoinduction and subsequent exposure.