Fig. 1: Study flowchart of identifying eligible COVID-19 patients and nirmatrelvir/ritonavir users for inclusion in the two target trial emulations.

Adult nirmatrelvir/ritonavir users with confirmed SARS-CoV-2 infection diagnosis during the study period were identified from the data source. Following the application of study inclusion and exclusion criteria, 87,070 nirmatrelvir/ritonavir users were included for the mortality or hospitalization analysis and 9669 nirmatrelvir/ritonavir users were included for the viral burden rebound analysis.