1. according to protocol v3.0, note: patients with mild-to-moderate disease who are placed in a facility where required by local guidelines can be enrolled. 2. have oxygen saturation (spo2) ≤93 % on room air at sea level or a ratio of arterial oxygen partial pressure (pao2 in millimeters of mercury) to fractional inspired oxygen (fio2) \<300, respiratory rate ≥30 per minute, heart rate ≥125 per minute. 3. have evidence of multi-organ dysfunction/failure. 4. systolic blood pressure \<90 mmhg, diastolic blood pressure \<60 mmhg, or requiring vasopressors. 5. require or anticipated impending need for endotracheal intubation and mechanical ventilation, oxygen delivered by high-flow nasal cannula noninvasive positive pressure ventilation, extracorporeal membrane oxygenation (ecmo).

1. according to protocol v3.0, note: patients with mild-to-moderate disease who are placed in a facility where required by local guidelines can be enrolled. 2. have oxygen saturation (spo2) ≤93 % on room air at sea level or a ratio of arterial oxygen partial pressure (pao2 in millimeters of mercury) to fractional inspired oxygen (fio2) \<300, respiratory rate ≥30 per minute, heart rate ≥125 per minute. 3. have evidence of multi-organ dysfunction/failure. 4. systolic blood pressure \<90 mmhg, diastolic blood pressure \<60 mmhg, or requiring vasopressors. 5. require or anticipated impending need for endotracheal intubation and mechanical ventilation, oxygen delivered by high-flow nasal cannula noninvasive positive pressure ventilation, extracorporeal membrane oxygenation (ecmo).

according to protocol v3.0, note: patients with mild-to-moderate disease who are placed in a facility where required by local guidelines can be enrolled. have oxygen saturation (spo2) ≤93 % on room air at sea level or a ratio of arterial oxygen partial pressure (pao2 in millimeters of mercury) to fractional inspired oxygen (fio2) <300, respiratory rate ≥30 per minute, heart rate ≥125 per minute. have evidence of multi-organ dysfunction/failure. systolic blood pressure <90 mmhg, diastolic blood pressure <60 mmhg, or requiring vasopressors. require or anticipated impending need for endotracheal intubation and mechanical ventilation, oxygen delivered by high-flow nasal cannula noninvasive positive pressure ventilation, extracorporeal membrane oxygenation (ecmo).

according to protocol v3.0, note: patients with mild-to-moderate disease who are placed in a facility where required by local guidelines can be enrolled. have oxygen saturation (spo2) ≤93 % on room air at sea level or a ratio of arterial oxygen partial pressure (pao2 in millimeters of mercury) to fractional inspired oxygen (fio2) <300, respiratory rate ≥30 per minute, heart rate ≥125 per minute. have evidence of multi-organ dysfunction/failure. systolic blood pressure <90 mmhg, diastolic blood pressure <60 mmhg, or requiring vasopressors. require or anticipated impending need for endotracheal intubation and mechanical ventilation, oxygen delivered by high-flow nasal cannula noninvasive positive pressure ventilation, extracorporeal membrane oxygenation (ecmo).

have been admitted to a hospital prior to randomization, or is hospitalized (inpatient) at randomization due to covid-19. have oxygen saturation (spo2) ≤93 % on room air at sea level or a ratio of arterial oxygen partial pressure (pao2 in millimeters of mercury) to fractional inspired oxygen (fio2) <300, respiratory rate ≥30 per minute, heart rate ≥125 per minute. have evidence of multi-organ dysfunction/failure. systolic blood pressure <90 mmhg, diastolic blood pressure <60 mmhg, or requiring vasopressors. require or anticipated impending need for endotracheal intubation and mechanical ventilation, oxygen delivered by high-flow nasal cannula noninvasive positive pressure ventilation, extracorporeal membrane oxygenation (ecmo).

have been admitted to a hospital prior to randomization, or is hospitalized (inpatient) at randomization due to covid-19. have oxygen saturation (spo2) ≤93 % on room air at sea level or a ratio of arterial oxygen partial pressure (pao2 in millimeters of mercury) to fractional inspired oxygen (fio2) <300, respiratory rate ≥30 per minute, heart rate ≥125 per minute. have evidence of multi-organ dysfunction/failure. systolic blood pressure <90 mmhg, diastolic blood pressure <60 mmhg, or requiring vasopressors. require or anticipated impending need for endotracheal intubation and mechanical ventilation, oxygen delivered by high-flow nasal cannula noninvasive positive pressure ventilation, extracorporeal membrane oxygenation (ecmo).