Pharmacokinetic Interactions and Safety of Coadministration of Glecaprevir and Pibrentasvir in Healthy Volunteers.

BACKGROUND AND OBJECTIVE: Glecaprevir and pibrentasvir are pangenotypic direct-acting antiviral agents for the treatment of chronic hepatitis C virus infection. The aim of the present study was to evaluate the drug-drug interaction and safety of glecaprevir and pibrentasvir coadministration in healthy volunteers.

METHODS: In this open-label, randomized, multiple-dose, Phase 1 study in 72 subjects, glecaprevir (100-1200 mg once daily) and pibrentasvir (40-200 mg once daily) were administered alone for 7 days and then in combination for another 7 days. Intensive blood sampling was performed on Days 1, 7, 8, and 14, and pharmacokinetic interactions were assessed using a repeated measures analysis of glecaprevir and pibrentasvir maximum plasma concentration (C max ) and area under the curve (AUC).

RESULTS: Coadministration of glecaprevir 400 mg increased pibrentasvir 120 and 40 mg steady-state C max and AUC values to 2.9-6.3-fold, and coadministration of glecaprevir 700 mg increased pibrentasvir 160 mg steady-state C max and AUC24 values to up to sevenfold of the values when pibrentasvir was administered alone. Glecaprevir C max and AUC values during coadministration were less than 1.5-fold of the values when glecaprevir was administered alone. The combination of glecaprevir and pibrentasvir at doses up to 400 mg was well tolerated by the healthy subjects in this study. High glecaprevir exposures at 700 and 1200 mg were associated with grade 2/3 elevations in alanine aminotransferase, aspartate aminotransferase, and/or bilirubin.

CONCLUSIONS: Coadministration of pibrentasvir 120 mg with glecaprevir doses up to 400 mg resulted in increases in pibrentasvir exposures without significant changes in glecaprevir exposures in the absence of any clinically significant laboratory abnormalities.