Sofosbuvir is a new drug candidate for hepatitis C treatment, with the chemical name L-Alanine, N-[[P(S),2′R]-2′-deoxy-2′-fluoro-2′-methyl-P-phenyl-5′-uridylyl]-, 1-methylethyl ester and a molecular formula of C22H29FN3O9P.Previously known as PS-7977 or GS-7977, it has shown promising results in numerous in vitro studies against all the genotypes of HCV. It is a nucleotide analog that is a highly potent inhibitor of the NS5B polymerase in HCV. This drug has shown high efficacy in combination with several other drugs with and without PEG-INF, against HCV.
Sofosbuvir is of special interest among the directly acting antiviral drugs under development, due to its high potency, low side effects, oral administration, and high barrier to resistance.
Although regimens containing protease inhibitors have resulted in higher SVR and shorter duration of treatment their limitations include a low genetic barrier to resistance, more side effects, complex medication regimens, and a potential for drug interactions.
Researchers are now evaluating the combination of two or more antiviral agents,
with separate targets for possible interferon-free regimens with higher SVR and shorter duration of treatment