4'-Fluorouridine is a broad-spectrum orally efficacious antiviral blocking respiratory syncytial virus and SARS-CoV-2 replication

Sourimant, J.; Lieber, C.; Aggarwal, M.; Cox, R.; Wolf, J.; Yoon, J.-J.; Toots, M.; Ye, C.; Sticher, Z.; Kolykhalov, A. A.; Martinez-Sobrido, L.; Bluemling, G. R.; Natchus, M. G.; Painter, G. R.; Plemper, R. K.

doi:10.1101/2021.05.19.444875

bioRxiv · 10.1101/2021.05.19.444875

4'-Fluorouridine is a broad-spectrum orally efficacious antiviral blocking respiratory syncytial virus and SARS-CoV-2 replication

Sourimant, J.·Lieber, C.·Aggarwal, M.·Cox, R.·Wolf, J.·Yoon, J.-J.·Toots, M.·Ye, C.·Sticher, Z.·Kolykhalov, A. A.·Martinez-Sobrido, L.·Bluemling, G. R.·Natchus, M. G.·Painter, G. R.·Plemper, R. K.

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Abstract

The COVID-19 pandemic has underscored the critical need for broad-spectrum therapeutics against respiratory viruses. Respiratory syncytial virus (RSV) is a major threat to pediatric patients and the elderly. We describe 4-fluorouridine (4-FlU, EIDD-2749), a ribonucleoside analog that inhibits RSV, related RNA viruses, and SARS-CoV-2 with high selectivity index in cells and well-differentiated human airway epithelia. Polymerase inhibition in in vitro RdRP assays established for RSV and SARS-CoV-2 revealed transcriptional pauses at positions i or i+3/4 post-incorporation. Once-daily oral treatment was highly efficacious at 5 mg/kg in RSV-infected mice or 20 mg/kg in ferrets infected with SARS-CoV-2 WA1/2020 or variant-of-concern (VoC) isolate CA/2020, initiated 24 or 12 hours after infection, respectively. These properties define 4-FlU as a broad-spectrum candidate for the treatment of RSV, SARS-CoV-2 and related RNA virus infections. One-Sentence Summary4-Fluorouridine is an orally available ribonucleoside analog that efficiently treats RSV and SARS-CoV-2 infections in vivo.

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Sourimant, J., Lieber, C., Aggarwal, M., Cox, R., Wolf, J., Yoon, J.-J., Toots, M., Ye, C., Sticher, Z., Kolykhalov, A. A., Martinez-Sobrido, L., Bluemling, G. R., Natchus, M. G., Painter, G. R., Plemper, R. K.. 2021-05-20. 4'-Fluorouridine is a broad-spectrum orally efficacious antiviral blocking respiratory syncytial virus and SARS-CoV-2 replication. https://doi.org/10.1101/2021.05.19.444875

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