Impact of lamivudine-resistance mutations on entecavir treatment outcome in hepatitis B.

Background And Objective: Entecavir (ETV) is a potent inhibitor of viral replication in nucleos(t)ide analog (NA)-naive chronic hepatitis B patients with a very low rate of resistance (≤1.2%) over 5 years. The aim of this study was to assess the efficacy of ETV treatment in routine clinical practice and to investigate whether persistence of residual viral replication was the result of the emergence and selection of drug-resistant mutants.