
2.3. Randomization and blinding
EVENT, ADVERSE EVENT
Eligible patients will be randomly assigned to the 3 treatment arms in a 1:1:1 ratio using an interactive response technology, and a study intervention allocation table will be created. Randomization will be stratified by the time from the onset of COVID-19 to randomization (<72 hours vs ≥72 hours) and by SARS-CoV-2 vaccination history (vaccinated [first dose completed] vs unvaccinated). Placebo drugs will be indistinguishable in appearance, labeling, and packaging from treatment drugs. All relevant personnel, including the sponsor, patients, investigator, and subinvestigator, will remain blinded to the treatments. Unblinding at the request of the investigator may be permitted only in the event of an emergency or adverse event (AE) when knowledge of the intervention may be needed for an appropriate course of therapy.