Dasabuvir (ABT-333) is a non-nucleoside inhibitor of NS5B viral RNA-dependent RNA polymerase that inhibits recombinant NS5B polymerases derived from HCV genotype 1a and 1b clinical isolates with IC50 values between 2.2 and 10.7 nM. It is at least 7,000-fold selective for the inhibition of HCV genotype 1 polymerases over human/mammalian polymerases.