tetano
Editor, Senior Moderator
PLoS Negl Trop Dis. 2013 Dec 26;7(12):e2614. doi: 10.1371/journal.pntd.0002614.
Favipiravir (T-705) inhibits jun?n virus infection and reduces mortality in a Guinea pig model of argentine hemorrhagic Fever.
Gowen BB1, Juelich TL2, Sefing EJ3, Brasel T4, Smith JK2, Zhang L2, Tigabu B4, Hill TE2, Yun T2, Pietzsch C2, Furuta Y5, Freiberg AN6.
Author information
Abstract
BACKGROUND:
Jun?n virus (JUNV), the etiologic agent of Argentine hemorrhagic fever (AHF), is classified by the NIAID and CDC as a Category A priority pathogen. Presently, antiviral therapy for AHF is limited to immune plasma, which is readily available only in the endemic regions of Argentina. T-705 (favipiravir) is a broadly active small molecule RNA-dependent RNA polymerase inhibitor presently in clinical evaluation for the treatment of influenza. We have previously reported on the in vitro activity of favipiravir against several strains of JUNV and other pathogenic New World arenaviruses.
METHODOLOGY/PRINCIPAL FINDINGS:
To evaluate the efficacy of favipiravir in vivo, guinea pigs were challenged with the pathogenic Romero strain of JUNV, and then treated twice daily for two weeks with oral or intraperitoneal (i.p.) favipiravir (300 mg/kg/day) starting 1-2 days post-infection. Although only 20% of animals treated orally with favipiravir survived the lethal challenge dose, those that succumbed survived considerably longer than guinea pigs treated with placebo. Consistent with pharmacokinetic analysis that showed greater plasma levels of favipiravir in animals dosed by i.p. injection, i.p. treatment resulted in a substantially higher level of protection (78% survival). Survival in guinea pigs treated with ribavirin was in the range of 33-40%. Favipiravir treatment resulted in undetectable levels of serum and tissue viral titers and prevented the prominent thrombocytopenia and leucopenia observed in placebo-treated animals during the acute phase of infection.
CONCLUSIONS/SIGNIFICANCE:
The remarkable protection afforded by i.p. favipiravir intervention beginning 2 days after challenge is the highest ever reported for a small molecule antiviral in the difficult to treat guinea pig JUNV challenge model. These findings support the continued development of favipiravir as a promising antiviral against JUNV and other related arenaviruses.
PMID:
24386500
[PubMed - in process]
PMCID:
PMC3873268
Free PMC Article
http://www.ncbi.nlm.nih.gov/pubmed/24386500
Favipiravir (T-705) inhibits jun?n virus infection and reduces mortality in a Guinea pig model of argentine hemorrhagic Fever.
Gowen BB1, Juelich TL2, Sefing EJ3, Brasel T4, Smith JK2, Zhang L2, Tigabu B4, Hill TE2, Yun T2, Pietzsch C2, Furuta Y5, Freiberg AN6.
Author information
Abstract
BACKGROUND:
Jun?n virus (JUNV), the etiologic agent of Argentine hemorrhagic fever (AHF), is classified by the NIAID and CDC as a Category A priority pathogen. Presently, antiviral therapy for AHF is limited to immune plasma, which is readily available only in the endemic regions of Argentina. T-705 (favipiravir) is a broadly active small molecule RNA-dependent RNA polymerase inhibitor presently in clinical evaluation for the treatment of influenza. We have previously reported on the in vitro activity of favipiravir against several strains of JUNV and other pathogenic New World arenaviruses.
METHODOLOGY/PRINCIPAL FINDINGS:
To evaluate the efficacy of favipiravir in vivo, guinea pigs were challenged with the pathogenic Romero strain of JUNV, and then treated twice daily for two weeks with oral or intraperitoneal (i.p.) favipiravir (300 mg/kg/day) starting 1-2 days post-infection. Although only 20% of animals treated orally with favipiravir survived the lethal challenge dose, those that succumbed survived considerably longer than guinea pigs treated with placebo. Consistent with pharmacokinetic analysis that showed greater plasma levels of favipiravir in animals dosed by i.p. injection, i.p. treatment resulted in a substantially higher level of protection (78% survival). Survival in guinea pigs treated with ribavirin was in the range of 33-40%. Favipiravir treatment resulted in undetectable levels of serum and tissue viral titers and prevented the prominent thrombocytopenia and leucopenia observed in placebo-treated animals during the acute phase of infection.
CONCLUSIONS/SIGNIFICANCE:
The remarkable protection afforded by i.p. favipiravir intervention beginning 2 days after challenge is the highest ever reported for a small molecule antiviral in the difficult to treat guinea pig JUNV challenge model. These findings support the continued development of favipiravir as a promising antiviral against JUNV and other related arenaviruses.
PMID:
24386500
[PubMed - in process]
PMCID:
PMC3873268
Free PMC Article
http://www.ncbi.nlm.nih.gov/pubmed/24386500