A method and composition for treating a host infected with hepatitis C comprising administering an effective hepatitis C treatment amount of a described 1′, 2′ or 3′-modified nucleoside or a pharmaceutically acceptable salt or prodrug thereof, is provided.

Methods and compositions for treating hepatitis C virus

The disclosed invention provides compositions and methods of treating a Flaviviridae infection, including hepatitis C virus, West Nile Virus, yellow fever virus, and a rhinovirus infection in a host, including animals, and especially humans, using a (2′R)-2′-deoxy-2′-fluoro-2′-C-methyl nucleosides, or a pharmaceutically acceptable salt or prodrug thereof.

Modified fluorinated nucleoside analogues

2′ and/or 3′ prodrugs of 1′, 2′, 3′ or 4′-branched nucleosides, and their pharmaceutically acceptable salts and derivatives are described. These prodrugs are useful in the prevention and treatment of Flaviviridae infections, including HCV infection, and other related conditions. Compounds and compositions of the prodrugs of the present invention are described. Methods and uses are also provided that include the administration of an effective amount of the prodrugs of the present invention, or their pharmaceutically acceptable salts or derivatives. These drugs may optionally be administered in combination or alteration with further anti-viral agents to prevent or treat Flaviviridae infections and other related conditions.

Modified 2' and 3'-nucleoside prodrugs for treating flaviviridae infections

The RNA-dependent RNA polymerase of hepatitis C virus (HCV) is necessary for the replication of viral RNA and thus represents an attractive target for drug development. Several structural classes of nonnucleoside inhibitors (NNIs) of HCV RNA polymerase have been described, including a promising series of benzothiadiazine compounds that efficiently block replication of HCV subgenomic replicons in tissue culture. In this work we report the selection of replicons resistant to inhibition by the benzothiadiazine class of NNIs. Four different single mutations were identified in separate clones, and all four map to the RNA polymerase gene, validating the polymerase as the antiviral target of inhibition. The mutations (M414T, C451R, G558R, and H95R) render the HCV replicons resistant to inhibition by benzothiadiazines, though the mutant replicons remain sensitive to inhibition by other nucleoside and NNIs of the HCV RNA polymerase. Additionally, cross-resistance studies and synergistic inhibition of the enzyme by combinations of a benzimidazole and a benzothiadiazine indicate the existence of nonoverlapping binding sites for these two structural classes of inhibitors.

Michelle P Walker

Papers

HCV RNA-dependent RNA polymerase as a target for antiviral development