Novel nonnucleoside inhibitor of hepatitis C virus RNA-dependent RNA polymerase.
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.
Howe
Anita Y M
AY
Infectious Diseases Wyeth Research, Pearl River, New York 10965, USA. howeaym@wyeth.com
Bloom
Johnathan
J
Baldick
Carl J
CJ
Benetatos
Christopher A
CA
Cheng
Huiming
H
Christensen
Joel S
JS
Chunduru
Srinivas K
SK
Coburn
Glen A
GA
Feld
Boris
B
Gopalsamy
Ariamala
A
Gorczyca
William P
WP
Herrmann
Steve
S
Johann
Stephen
S
Jiang
Xiaoqun
X
Kimberland
Michelle L
ML
Krisnamurthy
Girija
G
Olson
Matthew
M
Orlowski
Mark
M
Swanberg
Steve
S
Thompson
Ian
I
Thorn
Megan
M
Del Vecchio
Alfred
A
Young
Dorothy C
DC
van Zeijl
Marja
M
Ellingboe
John W
JW
Upeslacis
Janis
J
Collett
Marc
M
Mansour
Tarek S
TS
O'Connell
John F
JF
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
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