Drug Interactions between ranitidine bismuth citrate and sofosbuvir / velpatasvir

ADJUST DOSE: Coadministration of velpatasvir with H2-receptor antagonists may reduce its gastrointestinal absorption. Velpatasvir exhibits pH-dependent solubility, with increased solubility at lower pH. In 60 healthy volunteers, mean velpatasvir peak plasma concentration (Cmax) and systemic exposure (AUC) decreased by 20% and 19%, respectively, when a single 400 mg-100 mg dose of sofosbuvir-velpatasvir was administered simultaneously with a 40 mg dose of famotidine. When the famotidine dose was given 12 hours before the sofosbuvir-velpatasvir dose, mean velpatasvir Cmax decreased by 13% and AUC decreased by 15%. These alterations are not considered clinically significant. However, higher dosages of famotidine or another H2-receptor antagonist may result in a greater magnitude of interaction.

MANAGEMENT: H2-receptor antagonists may be administered simultaneously with or 12 hours apart from sofosbuvir-velpatasvir at a dose that does not exceed the equivalent of famotidine 40 mg twice daily.