Safety and Efficacy of Ombitasvir/Paritaprevir/Ritonavir Plus Dasabuvir With or Without Ribavirin in HCV-Infected Patients Taking Concomitant Acid-Reducing Agents

OBJECTIVES: Acid-reducing agents (ARAs) and proton-pump inhibitors (PPIs) that increase gastric pH can alter the bioavailability of antiviral drugs, particularly relevant in patients with advanced liver disease caused by chronic hepatitis C virus (HCV) infection seeking therapy. Using integrated data from six phase 3 studies, we report the safety and efficacy of the 3-direct-acting antiviral (DAA) regimen containing ombitasvir (OBV, an NS5A inhibitor), ritonavir-boosted paritaprevir (PTV/r, an NS3/4A protease inhibitor), and dasabuvir (DSV, an NS5B polymerase inhibitor) with or without ribavirin (RBV) for HCV genotype 1 patients taking concomitant ARAs and PPIs. METHODS: Treatment-naïve or peginterferon/RBV treatment-experienced patients with or without compensated cirrhosis received OBV/PTV/r and DSV with or without weight-based RBV. Rates of sustained virologic response (SVR), defined as HCV RNA below the lower limit of quantification, 12 weeks post-treatment (SVR12) and safety were evaluated in patients who were receiving concomitant ARAs. RESULTS: Among 2,053 patients enrolled and dosed with study drug, 410 (20%) were receiving concomitant ARAs; of these, 308 (15%) were taking concomitant PPIs. Rates of SVR12 were 95.9% (95% confidence interval (CI) 93.5–97.4%) among patients receiving an ARA, and 96.3% (95% CI 95.3–97.2%) in patients not receiving a concomitant ARA. Similarly, among patients receiving a PPI or not, SVR12 was achieved in 95.1% (95% CI 92.1–97.0%) and 96.4% (95% CI 95.5–97.2%), respectively. Response rates were high regardless of treatment regimen (with or without RBV), and among patients receiving a standard or high dose of PPIs. Regarding safety, adverse events and serious adverse events were more frequently reported in patients taking concomitant ARAs, though baseline population differences may have played a role. CONCLUSIONS: In phase 3 trials of OBV/PTV/r plus DSV and RBV in HCV genotype 1-infected patients, SVR12 rates were high regardless of ARA/PPI use or PPI dose. These data support the co-administration of this regimen with ARAs including PPIs.