2.9.1. Analysis populations.
SARS-CoV-2 infection
SECONDARY, SARS-COV-2 INFECTION
Primary and secondary endpoints and other efficacy endpoints, except for endpoints related to the viral titer, will be assessed in the intention-to-treat (ITT) population, comprising all patients randomized to a study intervention and having SARS-CoV-2 infection confirmed by an RT-PCR test based on the nasopharyngeal swab sample from Visit 1 (preintervention). Secondary endpoints and other efficacy endpoints related to the SARS-CoV-2 viral titer will be assessed in the modified ITT (mITT) population, comprising all patients randomized to a study intervention with positive RT-PCR test results on Visit 1 and a SARS-CoV-2 viral titer detected at baseline. All safety assessments will be conducted in the safety analysis population comprising patients who were randomized to a study intervention and who received at least 1 dose of the study intervention.The population whose time from onset of COVID-19 to randomization in the ITT (or mITT for viral titer-based endpoints) population is <72 hours will be the primary analysis population for both the primary and key secondary endpoints. If a significant difference is found in the populations, the same analysis as the primary endpoint and key secondary endpoints will be performed on the entire ITT (or mITT) population.Pharmacokinetic/pharmacodynamic analysis of the phase 2b study showed no clear difference in the antiviral efficacy between ensitrelvir 125 mg and 250 mg.