Introduction: Molnupiravir and Nirmatrelvir/r (NMV-r) have been proven to reduce severe Coronavirus Disease 2019 (COVID-19) in unvaccinated high-risk individuals. Data regarding their impact in fully vaccinated vulnerable subjects with mild-to-moderate COVID-19 are still limited, particularly in the era of Omicron and sub-variants.
Methods: Our retrospective study aimed to compare the safety profile and effectiveness of the two antivirals in all consecutive high-risk outpatients between 11 January and 10 July 2022. A logistic regression model was carried out to assess factors associated with the composite outcome defined as all-cause hospitalization and/or death at 30 days.
Results: A total of 719 individuals were included: 554 (77%) received Molnupiravir, whereas 165 (23%) were NMV-r users. Overall, 43 all-cause hospitalizations (5.9%) and 13 (1.8%) deaths were observed at 30 days. A composite outcome occurred in 47 (6.5%) individuals. At multivariate analysis, male sex [OR 3.785; p = 0.0021], age ≥ 75 [OR 2.647; p = 0.0124], moderate illness [OR 16.75; p < 0.001], and treatment discontinuation after medical decision [OR 8.148; p = 0.0123] remained independently associated with the composite outcome.
Conclusions: No differences between the two antivirals were observed. In this real-life setting, the early use of both of the oral antivirals helped limit composite outcome at 30 days among subjects who were at high risk of disease progression.
Keywords: COVID-19; Molnupiravir; Nirmatrelvir; SARS-CoV-2; antivirals.