Clinical effectiveness and safety of simnotrelvir/ritonavir and nirmatrelvir/ritonavir in the treatment of moderate to severe COVID-19 patients

<bold>Objective</bold> To compare the clinical outcomes between the simnotrelvir/ritonavir and nirmatrelvir/ritonavir in patients with moderate to severe COVID-19. <bold>Methods</bold> From May 30, 2023 to October 8, 2023, 115 patients with moderate to severe COVID-19 were retrospectively collected from Wenzhou Central Hospital (N=58 patients in the simnotrelvir/ritonavir group, N=57 patients in the nirmatrelvir/ritonavir group). The clinical effectiveness and adverse reactions were analyzed. <bold>Results</bold> Among moderate COVID-19 patients, the duration of recovery was significantly shorter in the simnotrelvir/ritonavir group than in the nirmatrelvir/ritonavir group [6.0 (5.0, 8.0) vs. 8.0 (6.0, 10.0) days, P = 0.011, HR = 1.74 (95% CI 1.135 – 2.669)]. Similar composite disease progression rate (10.3% vs. 7.0%, P = 0.730), hospitalization rate (79.3% vs. 75.4%, P = 0.661), and mortality rate (5.2% vs. 3.5%, P = 1.000) were observed between the simnotrelvir/ritonavir group and the nirmatrelvir/ritonavir group. The duration of recovery was 7.0 (5.25, 9.0) days and 8.0 (6.0, 11.0) days, and the SARS-CoV-2 nucleic acid or antigen shedding time was 6.0 (5.0, 7.0) days and 6.0 (5.0, 9.0) days in the simnotrelvir/ritonavir group and nirmatrelvir/ritonavir group, respectively. Among the adverse reactions, 5 (8.6%) occurred in the simnotrelvir/ritonavir group and 6 (10.5%) in the nirmatrelvir/ritonavir group (P = 0.762). <bold>Conclusion</bold> This study demonstrated comparable effectiveness in protecting against COVID-19 progression, hospitalization and mortality. Besides, the use of simnotrelvir/ritonavir significantly shorten the time to symptoms recovery in moderate COVID-19 patients.