Clinical status of subject at day 15 (on a 7-point ordinal scale): 1. Not hospitalized, no limitations on activities 2. Not hospitalized, limitation on activities, 3. Hospitalized, not requiring supplemental oxygen, 4. Hospitalized, requiring supplemental oxygen, 5. Hospitalized, on non-invasive ventilation or high flow oxygen devices, 6. Hospitalized, on invasive mechanical ventilation or ECMO, 7. Death. Primary outcome will be time from Day 0 to sustained clinical improvement or life discharge, whichever comes first, whereby a sustained clinical improvement is defined as an improvement of ≥ 2 points vs the highest value of Day 0 and 1 and sustained for at least 3 days.

Clinical status of subject at day 15 (on a 7-point ordinal scale): 1. Not hospitalized, no limitations on activities 2. Not hospitalized, limitation on activities, 3. Hospitalized, not requiring supplemental oxygen, 4. Hospitalized, requiring supplemental oxygen, 5. Hospitalized, on non-invasive ventilation or high flow oxygen devices, 6. Hospitalized, on invasive mechanical ventilation or ECMO, 7. Death. Primary outcome will be time from Day 0 to sustained clinical improvement or life discharge, whichever comes first, whereby a sustained clinical improvement is defined as an improvement of ≥ 2 points vs the highest value of Day 0 and 1 and sustained for at least 3 days.