Resistance-associated substitutions in patients with chronic hepatitis C virus genotype 4 infection

摘要

Data on the prevalence of resistance-associated substitutions (RASs) and their implications for treatment with direct-acting antivirals (DAAs) are sparse in European patients with HCV genotype 4. This study investigated RASs before and after DAA failure in different genotype 4 subtypes and evaluated retreatment efficacies. Samples of 195 genotype 4-infected patients were collected in the European Resistance Database and investigated for NS3, NS5A and NS5B RASs. Retreatment efficacies in DAA failure patients were analysed retrospectively. After NS5A inhibitor (NS5Ai) failure, subtype 4r was frequent (30) compared to DAA-naive patients (5) and the number of NS5A RASs was significantly higher in subtype 4r compared to 4a or 4d (median three RASs vs no or one RAS, respectively,P = 90 across all subtypes and first-line treatment regimens.