Molnupiravir (EIDD-2801) is an orally bioavailable proagent of the ribonucleoside analog EIDD-1931. Molnupiravir has broad spectrum antiviral activity against influenza virus and multiple coronaviruses, such as SARS-CoV-2, MERS-CoV, SARS-CoV. Molnupiravir has the potential for the research of COVID-19, and seasonal and pandemic influenza.