RO5428029

RO5428029 is a small molecule nucleoside inhibitor developed by Roche for the treatment of chronic hepatitis C virus (HCV) infection. It specifically targets the HCV NS5B RNA-dependent RNA polymerase, an essential enzyme for the replication of the viral genome. As a nucleoside analog, RO5428029 is phosphorylated intracellularly to its active triphosphate form, which then competes with natural nucleotides for incorporation into the growing RNA strand by the NS5B polymerase, leading to premature chain termination. The compound was evaluated in Phase 1 clinical trials to assess its safety, tolerability, and pharmacokinetics in both healthy volunteers and patients with HCV genotype 1, but development was subsequently discontinued.