Oral 4’fluorouridine provides postexposure protection against lethal Nipah virus infection

There are no approved medical countermeasures for combatting Nipah virus (NiV) which causes regular outbreaks in humans and animals in South and Southeast Asia with mortality rates in humans ranging from 40% to more than 90%. Recently, it was shown that 4'-fluorouridine (4'-FlU; EIDD-2749), an orally available ribonucleoside analog, protected guinea pigs and nonhuman primates from lethal challenge with Lassa virus and that 4'-FlU has <i>in vitro</i> antiviral activity against NiV. Here, we assessed the postexposure protective efficacy of 4'-FlU in a lethal hamster model of NiV infection. Daily treatment with 4'-FlU beginning 3 days after exposure to NiV resulted in complete protection from lethal infection. Our findings support the further development of 4'-FlU as a therapy for NiV disease.