Molnupiravir in Nonhospitalized Patients Molnupiravir induces viral mutations to a threshold beyond which Covid-19 cannot replicate. For nonhospitalized adults with mild-to-moderate Covid-19 symptoms before randomization, molnupiravir did not have dose-related effects on adverse events or laboratory results; 3.1% of patients were hospitalized or died compared with 5.4% treated with placebo.