The HCV NS5B RNA-dependent RNA polymerase, which is necessary for viral replication, is pan-genotypic inhibited by sofosbuvir. The pharmacologically active uridine analog triphosphate (GS-461203), which is created when sofosbuvir, a nucleotide prodrug, undergoes intracellular metabolism, can be integrated into HCV RNA by the NS5B polymerase and function as a chain terminator. Velpatasvir: This HCV inhibitor works by inhibiting the HCV NS5A protein, which is necessary for the assembly of HCV virions as well as RNA replication. Velpatasvir targets NS5A as part of its mode of action, according to research on cross-resistance and resistance selection in cell culture.