Effectiveness of oral antivirals in reducing adverse outcomes in asthmatic patients with non-severe COVID-19: A multi-institutional retrospective cohort study

Preventing the progression of coronavirus disease 2019 (COVID-19) is a critical issue, particularly in patients with comorbidities such as asthma. However, real-world data on the effectiveness of oral antivirals in patients with asthma and non-severe COVID-19 are limited. This study was conducted to evaluate the effectiveness of 2 oral antivirals, nirmatrelvir/ritonavir (NMV-r) and molnupiravir, in reducing adverse outcomes in asthmatic patients with non-severe COVID-19. This retrospective cohort study included non-hospitalized adults with asthma who were diagnosed with COVID-19 between January 1, 2022, and March 16, 2024, using data from the TriNetX Research Network. The study group received NMV-r or molnupiravir; the control group received no antivirals. Covariates were balanced between the groups using propensity score matching. The primary outcome was the composite incidence of all-cause mortality, all-cause hospitalization, and mechanical ventilation use within 30 days. After matching, each group comprised 19,235 patients. The study group showed significantly lower composite primary outcome (hazard ratio [HR]: 0.57; 95% confidence interval [CI]: 0.49-0.66). Specifically, the study group was associated with significantly lower risk of all-cause hospitalization (HR: 0.59; 95% CI: 0.50-0.69) and all-cause mortality (HR: 0.34; 95% CI: 0.16-0.73) and mechanical ventilation requirements (HR: 0.08; 95% CI: 0.01-0.58). Significantly risk reduction was also observed in subgroups including both sexes, different ages, those with hypertension, dyslipidemia, diabetes mellitus, those receiving NMV-r, and those who had received less than 1 dose and more than 3 doses of vaccine. Our findings suggest oral antivirals, particularly NMV-r, reduce adverse outcomes in asthmatic patients with non-severe COVID-19.