GS-621763 (E1112-GRP)

GS-621763, an orally bioavailable prodrug of GS-441524, shows a dose-dependent antiviral effect on SARS-CoV-2 reporter virus expressing nanoluciferase (SARS-CoV-2 nLUC) replication with an EC50 of 2.8 μM, also inhibits reporter SARS-CoV-2 expressing firefly luciferase (SARS-CoV-2 Fluc) replication with EC50 of 0.125 μM.