Time from the first day of randomization to the 28th day of study completion; that a participant achieves a two-point decrease in their admission status using a six-point ordinal scale or discharged alive from the hospital (depending on which comes first). The seven-point scale has been used in clinical trial for severe influenza; modified into a six-point scale due to the protracted course of COVID-19. The six-point ordinal scale ranges from 1-discharged or about to; Discharge criteria is defined by no fever; normal breathing (<24cpm); Sa02>94%; cough relieved; all sustained for not less than 3 days; 2-hospitalized but does not need oxygen treatment; 3-hospitalized and needs oxygen but not high flow or non-invasive ventilation; 4-hospitalized and needs high flow or non-invasive ventilation; 5-hospitalized for ECMO or invasive ventilation; to 6-death. [Time to two-point decrease in the six-point ordinal scale. To be assessed daily from 1st day of randomization till day 28 from randomization]

Time from the first day of randomization to the 28th day of study completion; that a participant achieves a two-point decrease in their admission status using a six-point ordinal scale or discharged alive from the hospital (depending on which comes first). The seven-point scale has been used in clinical trial for severe influenza; modified into a six-point scale due to the protracted course of COVID-19. The six-point ordinal scale ranges from 1-discharged or about to; Discharge criteria is defined by no fever; normal breathing (<24cpm); Sa02>94%; cough relieved; all sustained for not less than 3 days; 2-hospitalized but does not need oxygen treatment; 3-hospitalized and needs oxygen but not high flow or non-invasive ventilation; 4-hospitalized and needs high flow or non-invasive ventilation; 5-hospitalized for ECMO or invasive ventilation; to 6-death. [Time to two-point decrease in the six-point ordinal scale. To be assessed daily from 1st day of randomization till day 28 from randomization]