Efficacy of Molnupiravir in reducing the risk of severe outcome in patients with SARS-CoV-2 infection: a real-life full-matched case-control study (SAVALO Study).

Abstract

Introduction Molnupiravir (MNP) is an orally administered prodrug which prevents disease progression in patients at high risk for severe COVID-19. We conducted a real-life case-control study on a cohort of outpatients, with Omicron SARS-CoV-2 infection to assess the effectiveness of MNP in reducing the occurrence of hospital admission, admission in intensive care unit (ICU) and death at day 28. Materials and methods Cases were enrolled among SARS-CoV-2 positive subjects that sought medical care during the first five days of symptoms from January 1st, 2022, to December 31st, 2022, and received MNP. Control participants were selected from a regional database among those who tested positive during the study period and did not receive antiviral treatment for SARS-CoV-2. Results 1382 patients were included (cases: 146, controls: 1236). Vaccinated patients showed lower risk of mortality and composite outcome (at least one among hospital admission, admission in ICU and all-cause death) compared to unvaccinated ones (0.6% vs 7.8%, p<0.001 and 2% vs 7.8%, p=0.001 respectively). After full-matching propensity score, MNP-treated subjects showed a lower incidence of composite outcome, while no effect was observed on the single outcomes. In the subgroup analysis according to the vaccination status, MNP proved effective in preventing all the outcomes among unvaccinated patients, while showed to reduce the risk of ICU admission both in vaccinated and unvaccinated patients. Conclusions Treatment with MNP proved effective in reducing the risk of composite outcome among outpatients with SARS-CoV-2 infection. The beneficial effect of MNP treatment in reducing progression is more pronounced in unvaccinated patients.