Drug Interaction Report

Consumer information for this interaction is not currently available.

MONITOR: Coadministration with inducers of CYP450 3A4 may decrease the plasma concentrations of elbasvir and grazoprevir, both of which are substrates of the isoenzyme. In 10 study subjects, administration of elbasvir 50 mg once daily with efavirenz 600 mg once daily decreased elbasvir peak plasma concentration (Cmax), systemic exposure (AUC) and trough plasma concentration (Cmin) by 45%, 54% and 59%, respectively, compared to administration of elbasvir alone. Likewise, when grazoprevir 200 mg once daily and efavirenz 600 mg once daily were given together to 12 study subjects, grazoprevir Cmax, AUC and Cmin decreased by 87%, 83% and 69%, respectively. Efavirenz is generally considered a moderate inducer of CYP450 3A4. The extent to which other, less potent inducers of CYP450 3A4 may interact with elbasvir and grazoprevir is unknown.

MANAGEMENT: The potential for diminished pharmacologic effects of elbasvir-grazoprevir should be considered during coadministration with CYP450 3A4 inducers. Alternative treatments may be required if an interaction is suspected.

Information for this minor interaction is available on the professional version.