title: Novel nonnucleoside inhibitor of hepatitis C virus RNA-dependent RNA polymerase.
abstract: A novel nonnucleoside inhibitor of hepatitis C virus (HCV) RNA-dependent RNA polymerase (RdRp), [(1R)-5-cyano-8-methyl-1-propyl-1,3,4,9-tetrahydropyano[3,4-b]indol-1-yl] acetic acid (HCV-371), was discovered through high-throughput screening followed by chemical optimization. HCV-371 displayed broad inhibitory activities against the NS5B RdRp enzyme, with 50% inhibitory concentrations ranging from 0.3 to 1.8 microM for 90% of the isolates derived from HCV genotypes 1a, 1b, and 3a. HCV-371 showed no inhibitory activity against a panel of human polymerases, including mitochondrial DNA polymerase gamma, and other unrelated viral polymerases, demonstrating its specificity for the HCV polymerase. A single administration of HCV-371 to cells containing the HCV subgenomic replicon for 3 days resulted in a dose-dependent reduction of the steady-state levels of viral RNA and protein. Multiple treatments with HCV-371 for 16 days led to a >3-log10 reduction in the HCV RNA level. In comparison, multiple treatments with a similar inhibitory dose of alpha interferon resulted in a 2-log10 reduction of the viral RNA level. In addition, treatment of cells with a combination of HCV-371 and pegylated alpha interferon resulted in an additive antiviral activity. Within the effective antiviral concentrations of HCV-371, there was no effect on cell viability and metabolism. The intracellular antiviral specificity of HCV-371 was demonstrated by its lack of activity in cells infected with several DNA or RNA viruses. Fluorescence binding studies show that HCV-371 binds the NS5B with an apparent dissociation constant of 150 nM, leading to high selectivity and lack of cytotoxicity in the antiviral assays.
authors.affiliation: Infectious Diseases Wyeth Research, Pearl River, New York 10965, USA. howeaym@wyeth.com
authors.forename: Anita Y M
authors.initials: AY
authors.lastname: Howe
authors.forename: Johnathan
authors.initials: J
authors.lastname: Bloom
authors.forename: Carl J
authors.initials: CJ
authors.lastname: Baldick
authors.forename: Christopher A
authors.initials: CA
authors.lastname: Benetatos
authors.forename: Huiming
authors.initials: H
authors.lastname: Cheng
authors.forename: Joel S
authors.initials: JS
authors.lastname: Christensen
authors.forename: Srinivas K
authors.initials: SK
authors.lastname: Chunduru
authors.forename: Glen A
authors.initials: GA
authors.lastname: Coburn
authors.forename: Boris
authors.initials: B
authors.lastname: Feld
authors.forename: Ariamala
authors.initials: A
authors.lastname: Gopalsamy
authors.forename: William P
authors.initials: WP
authors.lastname: Gorczyca
authors.forename: Steve
authors.initials: S
authors.lastname: Herrmann
authors.forename: Stephen
authors.initials: S
authors.lastname: Johann
authors.forename: Xiaoqun
authors.initials: X
authors.lastname: Jiang
authors.forename: Michelle L
authors.initials: ML
authors.lastname: Kimberland
authors.forename: Girija
authors.initials: G
authors.lastname: Krisnamurthy
authors.forename: Matthew
authors.initials: M
authors.lastname: Olson
authors.forename: Mark
authors.initials: M
authors.lastname: Orlowski
authors.forename: Steve
authors.initials: S
authors.lastname: Swanberg
authors.forename: Ian
authors.initials: I
authors.lastname: Thompson
authors.forename: Megan
authors.initials: M
authors.lastname: Thorn
authors.forename: Alfred
authors.initials: A
authors.lastname: Del Vecchio
authors.forename: Dorothy C
authors.initials: DC
authors.lastname: Young
authors.forename: Marja
authors.initials: M
authors.lastname: van Zeijl
authors.forename: John W
authors.initials: JW
authors.lastname: Ellingboe
authors.forename: Janis
authors.initials: J
authors.lastname: Upeslacis
authors.forename: Marc
authors.initials: M
authors.lastname: Collett
authors.forename: Tarek S
authors.initials: TS
authors.lastname: Mansour
authors.forename: John F
authors.initials: JF
authors.lastname: O'Connell
mesh_terms: D000818:Animals; D000998:Antiviral Agents / Q000494:pharmacology*; D002478:Cells, Cultured; D002522:Chlorocebus aethiops; D003588:Cytopathogenic Effect, Viral; D004259:DNA-Directed DNA Polymerase / Q000378:metabolism; D004353:Drug Evaluation, Preclinical; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D004926:Escherichia coli / Q000235:genetics; D054303:HIV Reverse Transcriptase / Q000032:analysis / Q000378:metabolism; D016174:Hepacivirus / Q000187:drug effects* / Q000201:enzymology*; D006801:Humans; D007211:Indoles / Q000494:pharmacology*; D016898:Interferon-alpha / Q000494:pharmacology; D011714:Pyrans / Q000494:pharmacology*; D012324:RNA-Dependent RNA Polymerase / Q000037:antagonists & inhibitors*; D012093:Replicon / Q000187:drug effects; D013050:Spectrometry, Fluorescence; D013379:Substrate Specificity; D014709:Vero Cells; D017361:Viral Nonstructural Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D012697:Serine Endopeptidases; D043583:Nucleoside-Triphosphatase; D053487:DEAD-box RNA Helicases; D000085242:Viral Proteases
chemical_list: D000998:Antiviral Agents; D004259:DNA-Directed DNA Polymerase; D004791:Enzyme Inhibitors; D054303:HIV Reverse Transcriptase; D007211:Indoles; D016898:Interferon-alpha; D011714:Pyrans; D012324:RNA-Dependent RNA Polymerase; D017361:Viral Nonstructural Proteins; C495221:(5-cyano-8-methyl-1-propyl-1,3,4,9-tetrahydropyrano(3,4-b)indol-1-yl)acetic acid; C084422:NS3 protein, hepatitis C virus; D012697:Serine Endopeptidases; D043583:Nucleoside-Triphosphatase; D053487:DEAD-box RNA Helicases; D000085242:Viral Proteases; C087036:NS-5 protein, hepatitis C virus