Early Clinical Experience with Molnupiravir for Mild to Moderate Breakthrough COVID-19 among Fully Vaccinated Patients at Risk for Disease Progression.

Information on the efficacy and safety of molnupiravir in daily clinical practice is very scarce. We aimed to describe the clinical characteristics and outcomes of fully vaccinated patients with mild to moderate breakthrough COVID-19 treated with molnupiravir between January 2022 and February 2022. Overall, 145 patients were enrolled. Their median age was 71.0 years, and 60.7% were males. The most common underlying condition was a severe cardiovascular disease (37.2%), followed by primary or acquired immunodeficiency (22.8%), and oncological/onco-hematological disease in the active phase (22.1%). At 30 days after breakthrough COVID-19 diagnosis, only 4 out of 145 patients (2.7%) required hospital admission. No patients developed severe COVID-19, were admitted to the ICU, or died during the follow-up period. Adverse events, mild in intensity, occurred in 2 patients (1.4%). Our results support the current evidence establishing positive clinical and safety outcomes of molnupiravir in fully vaccinated patients with mild or moderate breakthrough COVID-19.