Molnupiravir – the prodrug of the active antiviral ribonucleoside analog ß-d-N4-hydroxycytidine (NHC; EIDD-1931), has activity against a number of RNA viruses including SARS-CoV-2, SARS-CoV, Middle East respiratory syndrome coronavirus (MERS), and seasonal and pandemic influenza viruses.

On evaluating single and multiple doses of molnupiravir in healthy volunteers, it was found that the drug appeared rapidly in plasma, with a median time of maximum observed concentration of 1-1.75 hours, and declined with a geometric half-life of approximately 1 hour. This agent showed a slower elimination phase following multiple doses or higher single doses. The maximum concentration was dose-dependent and accumulation was not apparent following multiple doses.

Additionally, molnupiravir was well tolerated. When taken with food, the rate of absorption of this agent deceased, but the overall exposure remained the same. Adverse events occurred in less than half of the subjects, were higher with placebo than with the drug and the majority were mild. Moreover, no episode of serious adverse event was reported.

Source: Antimicrobial Agents and Chemotherapy. 2021 Mar 1;65(5):e02428-20. doi: 10.1128/AAC.02428-20.