Real-life Effectiveness and Safety of the Daclatasvir/Asunaprevir Combination Therapy for Genotype 1b Chronic Hepatitis C Patients: An Emphasis on the Pretreatment NS5A Resistance-Associated Substitution Test

Abstract

This study aimed to investigate the real‐life effectiveness and safety of daclatasvir (DCV) and asunaprevir (ASV) combination therapy in Korean patients. We consecutively enrolled patients with genotype 1b hepatitis C virus (HCV) infection treated with at least one dose of DCV/ASV combination therapy in seven tertiary hospitals of South Korea. The sustained virologic response (SVR) rates and safety according to intention‐to‐treat (ITT) and per‐protocol (PP) analyses were evaluated. Among the 526 enrolled patients, 91% showed negative (87%) or “undetermined” (4%) resistance‐associated substitution (RAS); 9% did not undergo RAS testing. The SVR rates for ITT and PP were 89.3% and 95.0% in treatment‐naive patients and 93.2% and 95.6% in treatment‐experienced patients, respectively. In PP analysis, negative RAS was associated with higher SVR (96.3%) than with “undetermined RAS” (85.7%) or “not tested for RAS” (84.4%). Adverse events were reported in 185 (35.4%) patients, and events leading to discontinuation were observed in 4.3% of the study population. Forty‐two (8.0%) patients developed transaminase elevation (≥2 × upper normal limit), resulting in treatment discontinuation in six (1.1%) patients. DCV/ASV combination therapy showed acceptable efficacy in genotype 1b compensated HCV‐infected patients with negative pretreatment RAS. Although most adverse events were tolerable to continue antiviral treatment, adequate monitoring for transaminase elevation is warranted.