EIDD-2801 is an orally bioavailable prodrug of EIDD-1931, which has a broad-spectrum antiviral activity against 39 multiple coronaviruses, including SARS-CoV2, MERS-CoV, SARS-CoV. and related zoonotic group 2b or 2c Bat-CoVs, as well as increased potency against a coronavirus bearing resistance mutations to another nucleoside analog inhibitor.