Prevalence of drug-drug interactions with pangenotypic direct-acting antivirals for hepatitis C and real-world care management in the United States: a retrospective observational study

BACKGROUND: Direct-acting antiviral (DAA) regimens for hepatitis C virus (HCV) have varying potentials for drug-drug interactions (DDIs). OBJECTIVES: To (1) identify prevalence of potential DDI with glecaprevir-pibrentasvir (GLE-PIB) and sofosbuvir-velpatasvir (SOF-VEL) and (2) describe health care provider actions in response to pharmacist recommendations based on potential interactions with GLE-PIB or SOF-VEL, using 2 complementary data sources. METHODS: Possible interacting drugs were identified among adult patients in a United States electronic medical record database covering 21 health care organizations and 26 million patients in 2018. DDIs were categorized as potential weak interaction (Level 1), potential interaction (Level 2), or contraindicated (Level 3). Real-world recommendations and resultant actions regarding DDIs with GLE-PIB and SOF-VEL were obtained from a specialty pharmacy database. Categorical variable comparisons were done via chi-square analysis with subsequent z-tests of column proportions. RESULTS: DDI prevalence was higher for patients prescribed GLE-PIB (317/769 [41%]) compared with those prescribed SOF-VEL (170/633 [27%]), and the prevalence of a Level 3 (contraindicated) interaction was higher with GLE-PIB than SOF-VEL (61/769 [8%] vs 2/633 [< 1%]). Across all DDI levels, analgesics (139/317 [44%]), proton-pump inhibitors (129/317 [41%]), and lipid-lowering agents (59/317 [19%]) were the top drug classes for the GLE-PIB group with potential for DDI. For SOF-VEL prescribed patients, the top drug classes were proton-pump inhibitors (83/170 [49%]), histamine-2 blockers (42/170[25%]), and lipid-lowering agents (42/170 [25%]). In real-world care management, the overall prevalence of pharmacist recommendations regarding DDIs was significantly lower for SOF-VEL (28/419 [7%]) relative to GLE-PIB (151/1,216 [12%]). Recommended guidance from pharmacists was not followed for 39% (69/179) of patients, 36% (54/151) for GLE-PIB, and 54% (15/28) for SOF-VEL. CONCLUSIONS: The potential for DDIs with pangenotypic HCV DAAs is frequent and may be more frequent with GLE-PIB than SOF-VEL. Physician responses to pharmacist alerts regarding potential interaction can be highly variable, even in cases of contraindication.