Molnupiravir is an antiviral medication that inhibits the replication of certain RNA viruses. It is used to treat COVID-19 in those infected by SARS-CoV-2.[108]
Molnupiravir is a prodrug of the synthetic nucleoside derivative N4-hydroxycytidine and exerts its antiviral action through introduction of copying errors during viral RNA replication.[109][110]
Molnupiravir was originally developed to treat influenza at Emory University by the university's drug innovation company, Drug Innovation Ventures at Emory (DRIVE), but was reportedly abandoned for mutagenicity concerns.[111][112] It was then acquired by Miami-based company Ridgeback Biotherapeutics, which later partnered with Merck & Co. to develop the drug further.[113]
Based on positive results in placebo-controlled double-blind randomized clinical trials,[114][115] Molnupiravir was approved for medical use in the United Kingdom in November 2021.[108][116][117][118] In December 2021, the U.S. Food and Drug Administration (FDA) granted an emergency use authorization (EUA) to molnupiravir for use in certain populations where other treatments are not feasible.[119] The emergency use authorization was only narrowly approved (13-10) because of questions regarding efficacy and concerns that molnupiravir's mutagenic effects could create new variants that evade immunity and prolong the COVID-19 pandemic.[120][121][122]