In Vitro Effect of 1-β- d -Ribofuranosyl-1,2,4-Triazole-3-Carboxamide (Virazole, ICN 1229) on Deoxyribonucleic Acid and Ribonucleic Acid Viruses

Abstract

Virazole (1-β- d -ribofuranosyl-1,2,4-triazole-3-carboxamide) is a highly soluble new synthetic nucleoside having significant, reproducible activity against a broad spectrum of deoxyribonucleic acid and ribonucleic acid viruses in vitro. The drug inhibited viral cytopathogenic effects in monolayers of cells infected for 3 days with type 3 adeno, types 1 and 2 herpes, myxoma, cytomegalo, vaccinia, infectious bovine rhinotracheitis, types 1A, 2, 8, 13, and 56 rhino, types 1 and 3 parainfluenza, vesicular stomatitis, subacute sclerosing panencephalitis, Semliki Forest, Newcastle disease, and measles viruses. Hemagglutinin production by influenza A 2 , influenza B, and type 1 parainfluenza viruses in chicken embryo cells was reduced by Virazole treatment. Recoverable intra- and extracellular virus titers were reduced by the drug in experiments with type 1 herpes, vaccinia, type 3 parainfluenza, and vesicular stomatitis viruses. Plaque formation by type 1 herpesvirus was also inhibited by exposure of the infected cells to Virazole. Pretreatment of cells with the compound, followed by its removal before addition of type 1 herpesvirus, severely lessened the antiviral activity; the compound was still moderately effective in reducing the viral effects on the cells when added as long as 22 hr after the virus. Parallel experiments, in which the antiviral activity of a number of known active drugs was compared, indicated Virazole to have at least a comparable degree of activity, and it was also active against a wider variety of viruses than any of these known active materials. The CCED 50 of Virazole to chicken embryo cells was approximately 1,000 μg/ml, although concentrations as low as 10 μg/ml caused slight (15%) inhibition in total cellular protein after 72 hr of incubation.

Development and validation of a chemiluminescent immunodetection assay amenable to high throughput screening of antiviral drugs for Nipah and Hendra virus

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N-(3-Cyanophenyl)-2-phenylacetamide, an effective inhibitor of morbillivirus-induced membrane fusion with low cytotoxicity

“…It is a water-soluble synthetic nucleoside with broad-spectrum antiviral properties that has been shown to be active in vitro against many viruses (Huffman et al, 1973;Gururangan et al, 1990;Honda et al, 1994;Ishii et al, 1996;Chong et al, 2001;Graci & Cameron, 2006;Elia et al, 2008). Although RBV was used as an antiviral agent during the first NiV outbreak in 1999 in Malaysia, its antiviral properties could not be confirmed in the generally accepted hamster model (Georges-Courbot et al, 2006).…”

Broad-spectrum antiviral activity of 2-beta-D-ribofuranosylselenazole-4-carboxamide, a new antiviral agent

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