Assessment of drug interaction potential between the HCV direct-acting antiviral agents elbasvir/grazoprevir and the HIV integrase inhibitors raltegravir and dolutegravir

Background Elbasvir/grazoprevir is a once-daily fixed-dose combination therapy for the treatment of chronic HCV infection, including HCV/HIV coinfection. Objectives To evaluate the pharmacokinetic interaction of elbasvir and grazoprevir with raltegravir or dolutegravir. Methods Three open-label trials in healthy adult participants were conducted. In the raltegravir trials, participants received a single dose of raltegravir 400 mg, a single dose of elbasvir 50 mg or grazoprevir 200 mg, and raltegravir with either elbasvir or grazoprevir. In the dolutegravir trial, participants received a single dose of dolutegravir 50 mg alone or co-administered with once-daily elbasvir 50 mg and grazoprevir 200 mg. Results The raltegravir AUC0-∞ geometric mean ratio (GMR) (90% CI) was 1.02 (0.81-1.27) with elbasvir and 1.43 (0.89-2.30) with grazoprevir. Dolutegravir AUC0-∞ GMR (90% CI) was 1.16 (1.00-1.34) with elbasvir and grazoprevir. The elbasvir AUC0-∞ GMR (90% CI) was 0.81 (0.57-1.17) with raltegravir and 0.98 (0.93-1.04) with dolutegravir. The grazoprevir AUC0-24 GMR (90% CI) was 0.89 (0.72-1.09) with raltegravir and 0.81 (0.67-0.97) with dolutegravir. Conclusions Elbasvir or grazoprevir co-administered with raltegravir or dolutegravir resulted in no clinically meaningful drug-drug interactions and was generally well tolerated. These results support the assertion that no dose adjustments for elbasvir, grazoprevir, raltegravir or dolutegravir are needed for co-administration in HCV/HIV-coinfected people.