NCIt definition : An orally available prodrug of PSI-6130 which is a selective cytidine nucleoside analogue
and non-cytotoxic hepatitis C virus (HCV) polymerase inhibitor. After intracellular
uptake, mericitabine is phosphorylated into two active triphosphate metabolites, which
disable HCV RNA-dependent RNA polymerase (non-structural protein 5B; NS5B) upon binding.
This results in the blockage of viral HCV RNA production and thus viral replication.
This agent has a high barrier to resistance, however, a substitution mutation (S282T)
on HCV NS5B impairs mericitabine's activity significantly.;