New Perspectives on Antimicrobial Agents: Molnupiravir and Nirmatrelvir/Ritonavir for Treatment of COVID-19
Robert L. Atmar, Natalie Finch
Abstract
viral replication of all variants tested to date. Each is taken orally twice daily for 5 days. When started in the first 5 days of illness in persons at risk for complications due to COVID-19, molnupiravir and nirmatrelvir/ritonavir significantly decreased severe outcomes (hospitalizations and death) with adjusted relative risk reductions of 30% and 88%, respectively, for the two treatments. Molnupiravir should not be used in children or pregnant persons due to concerns about potential toxicity, and reliable contraception should be used in persons of childbearing potential. Nirmatrelvir/ritonavir may cause significant drug-to-drug interactions that limit its use in persons taking certain medications metabolized by certain cytochrome P450 enzymes. Both treatment regimens are important additions to the management of early COVID-19 in at-risk patients in the outpatient setting.