Bemnifosbuvir (AT-527, RO7496998) is an antiviral drug invented by Atea Pharmaceuticals and licensed to Roche for clinical development, a novel nucleotide analogprodrug originally developed for the treatment of hepatitis C.[1][2] Bemnifosbuvir is the orally bioavailable hemisulfate salt of AT-511, which is metabolized in several steps to the active nucleotide triphosphate AT-9010, acting as an RNA polymerase inhibitor and thereby interfering with viral replication. Bemnifosbuvir has been researched for the treatment of coronavirus diseases such as that produced by SARS-CoV-2.[3] It showed good results in early clinical trials but had inconsistent results at later stages.[4][5] Bemnifosbuvir's Phase III study ended early as it failed to meet its primary endpoint of symptom alleviation and did not decrease viral load. However, the drug was well-tolerated and reduced relative hospitalization risk by 71%.[6]
