* on invasive mechanical ventilation or on veno-venous ecmo for \>48 hours at time of screening * received an investigational intervention (including investigational vaccines) or used an invasive investigational medical device within 30 days before the planned dose of study intervention. note: the investigator must ensure that the participant is not enrolled in another covid-19 study with an investigational intervention (apart from the exception specified below) prior to completion of day 28 of the current study. exception: participation in a single arm study, a non-blinded controlled study, expanded access, compassionate use program or any other program that is not a blinded study is allowed if it is conducted with one of the following: agents with demonstrated in vitro-effect against sarscov- 2, as mentioned in the center of disease control and prevention (cdc) guidelines and convalescent plasma * current confirmed or high suspicion for pulmonary embolus, hemodynamic significant pericardial effusion, myocarditis, or class 3 or 4 congestive heart failure as defined by the new york heart association functional classification and/or current evidence of active cardiac ischemia * has a history of respiratory condition (that is, asthma, chronic obstructive pulmonary disease (copd), cystic fibrosis, fibrotic lung disease) that requires home oxygen supplementation, supportive non-invasive ventilation or, is status/post lung volume reduction surgery (lvrs). exception: participants with sleep apnea using supportive non-invasive ventilation (continuous positive airway pressure \[cpap\]) at screening may be included * on renal replacement therapy (defined as peritoneal dialysis or hemodialysis) * screening laboratory test result as follows: absolute neutrophil count (anc) \<1.0\*10\^3 cells/microliter; platelet count \<50\*10\^3 cells/microliter; estimated glomerular filtration rate (egfr) \<=30 milliliter per minute per 1.73 square meter (ml/min/1.73 m\^2); bilirubin \>2\* upper limit of normal (uln) unless bilirubin rise is due to gilbert's syndrome or of non-hepatic origin; alanine aminotransferase/ aspartate aminotransferase (alt) \>5\*uln; prothrombin time (pt)/international normalized ratio (inr) \>1.5\*uln or activated partial thromboplastin time (aptt) \>1.5\*uln related to known coagulopathy or bleeding disorder (the participant can receive anticoagulant therapies for underlying conditions, or as systematic thromboprophylaxis due to covid-19, or as part of the treatment of complications of covid-19, but cannot participate in a clinical study with anticoagulants for covid-19) * pregnant or breastfeeding, unless in the opinion of the investigator, the benefit outweighs the risks * has active hepatitis b or c infection or has human immunodeficiency virus infection or acquired immune deficiency syndrome (hiv/aids) based on medical history and/or concomitant medication * known active or latent tuberculosis (tb), history of incompletely treated tb, suspected or known extrapulmonary tb based on medical history and/or concomitant medication * evidence of active bacterial (including but not limited to bacterial pneumonia), fungal, viral or opportunistic infection (other than sars-cov-2) * currently active clinically significant (example, causing hemodynamic instability and/or causing hypoxemia) and uncontrolled arrhythmia

* on invasive mechanical ventilation or on veno-venous ecmo for \>48 hours at time of screening * received an investigational intervention (including investigational vaccines) or used an invasive investigational medical device within 30 days before the planned dose of study intervention. note: the investigator must ensure that the participant is not enrolled in another covid-19 study with an investigational intervention (apart from the exception specified below) prior to completion of day 28 of the current study. exception: participation in a single arm study, a non-blinded controlled study, expanded access, compassionate use program or any other program that is not a blinded study is allowed if it is conducted with one of the following: agents with demonstrated in vitro-effect against sarscov- 2, as mentioned in the center of disease control and prevention (cdc) guidelines and convalescent plasma * current confirmed or high suspicion for pulmonary embolus, hemodynamic significant pericardial effusion, myocarditis, or class 3 or 4 congestive heart failure as defined by the new york heart association functional classification and/or current evidence of active cardiac ischemia * has a history of respiratory condition (that is, asthma, chronic obstructive pulmonary disease (copd), cystic fibrosis, fibrotic lung disease) that requires home oxygen supplementation, supportive non-invasive ventilation or, is status/post lung volume reduction surgery (lvrs). exception: participants with sleep apnea using supportive non-invasive ventilation (continuous positive airway pressure \[cpap\]) at screening may be included * on renal replacement therapy (defined as peritoneal dialysis or hemodialysis) * screening laboratory test result as follows: absolute neutrophil count (anc) \<1.0\*10\^3 cells/microliter; platelet count \<50\*10\^3 cells/microliter; estimated glomerular filtration rate (egfr) \<=30 milliliter per minute per 1.73 square meter (ml/min/1.73 m\^2); bilirubin \>2\* upper limit of normal (uln) unless bilirubin rise is due to gilbert's syndrome or of non-hepatic origin; alanine aminotransferase/ aspartate aminotransferase (alt) \>5\*uln; prothrombin time (pt)/international normalized ratio (inr) \>1.5\*uln or activated partial thromboplastin time (aptt) \>1.5\*uln related to known coagulopathy or bleeding disorder (the participant can receive anticoagulant therapies for underlying conditions, or as systematic thromboprophylaxis due to covid-19, or as part of the treatment of complications of covid-19, but cannot participate in a clinical study with anticoagulants for covid-19) * pregnant or breastfeeding, unless in the opinion of the investigator, the benefit outweighs the risks * has active hepatitis b or c infection or has human immunodeficiency virus infection or acquired immune deficiency syndrome (hiv/aids) based on medical history and/or concomitant medication * known active or latent tuberculosis (tb), history of incompletely treated tb, suspected or known extrapulmonary tb based on medical history and/or concomitant medication * evidence of active bacterial (including but not limited to bacterial pneumonia), fungal, viral or opportunistic infection (other than sars-cov-2) * currently active clinically significant (example, causing hemodynamic instability and/or causing hypoxemia) and uncontrolled arrhythmia

- on invasive mechanical ventilation or on veno-venous ecmo for >48 hours at time of screening - received an investigational intervention (including investigational vaccines) or used an invasive investigational medical device within 30 days before the planned dose of study intervention. note: the investigator must ensure that the participant is not enrolled in another covid-19 study with an investigational intervention (apart from the exception specified below) prior to completion of day 28 of the current study. exception: participation in a single arm study, a non-blinded controlled study, expanded access, compassionate use program or any other program that is not a blinded study is allowed if it is conducted with one of the following: agents with demonstrated in vitro-effect against sarscov- 2, as mentioned in the center of disease control and prevention (cdc) guidelines and convalescent plasma - current confirmed or high suspicion for pulmonary embolus, hemodynamic significant pericardial effusion, myocarditis, or class 3 or 4 congestive heart failure as defined by the new york heart association functional classification and/or current evidence of active cardiac ischemia - has a history of respiratory condition (that is, asthma, chronic obstructive pulmonary disease (copd), cystic fibrosis, fibrotic lung disease) that requires home oxygen supplementation, supportive non-invasive ventilation or, is status/post lung volume reduction surgery (lvrs). exception: participants with sleep apnea using supportive non-invasive ventilation (continuous positive airway pressure [cpap]) at screening may be included - on renal replacement therapy (defined as peritoneal dialysis or hemodialysis) - screening laboratory test result as follows: absolute neutrophil count (anc) <1.0*10^3 cells/microliter; platelet count <50*10^3 cells/microliter; estimated glomerular filtration rate (egfr) <=30 milliliter per minute per 1.73 square meter (ml/min/1.73 m^2); bilirubin >2* upper limit of normal (uln) unless bilirubin rise is due to gilbert's syndrome or of non-hepatic origin; alanine aminotransferase/ aspartate aminotransferase (alt) >5*uln; prothrombin time (pt)/international normalized ratio (inr) >1.5*uln or activated partial thromboplastin time (aptt) >1.5*uln related to known coagulopathy or bleeding disorder (the participant can receive anticoagulant therapies for underlying conditions, or as systematic thromboprophylaxis due to covid-19, or as part of the treatment of complications of covid-19, but cannot participate in a clinical study with anticoagulants for covid-19) - pregnant or breastfeeding, unless in the opinion of the investigator, the benefit outweighs the risks - has active hepatitis b or c infection or has human immunodeficiency virus infection or acquired immune deficiency syndrome (hiv/aids) based on medical history and/or concomitant medication - known active or latent tuberculosis (tb), history of incompletely treated tb, suspected or known extrapulmonary tb based on medical history and/or concomitant medication - evidence of active bacterial (including but not limited to bacterial pneumonia), fungal, viral or opportunistic infection (other than sars-cov-2) - currently active clinically significant (example, causing hemodynamic instability and/or causing hypoxemia) and uncontrolled arrhythmia

- on invasive mechanical ventilation or on veno-venous ecmo for >48 hours at time of screening - received an investigational intervention (including investigational vaccines) or used an invasive investigational medical device within 30 days before the planned dose of study intervention. note: the investigator must ensure that the participant is not enrolled in another covid-19 study with an investigational intervention (apart from the exception specified below) prior to completion of day 28 of the current study. exception: participation in a single arm study, a non-blinded controlled study, expanded access, compassionate use program or any other program that is not a blinded study is allowed if it is conducted with one of the following: agents with demonstrated in vitro-effect against sarscov- 2, as mentioned in the center of disease control and prevention (cdc) guidelines and convalescent plasma - current confirmed or high suspicion for pulmonary embolus, hemodynamic significant pericardial effusion, myocarditis, or class 3 or 4 congestive heart failure as defined by the new york heart association functional classification and/or current evidence of active cardiac ischemia - has a history of respiratory condition (that is, asthma, chronic obstructive pulmonary disease (copd), cystic fibrosis, fibrotic lung disease) that requires home oxygen supplementation, supportive non-invasive ventilation or, is status/post lung volume reduction surgery (lvrs). exception: participants with sleep apnea using supportive non-invasive ventilation (continuous positive airway pressure [cpap]) at screening may be included - on renal replacement therapy (defined as peritoneal dialysis or hemodialysis) - screening laboratory test result as follows: absolute neutrophil count (anc) <1.0*10^3 cells/microliter; platelet count <50*10^3 cells/microliter; estimated glomerular filtration rate (egfr) <=30 milliliter per minute per 1.73 square meter (ml/min/1.73 m^2); bilirubin >2* upper limit of normal (uln) unless bilirubin rise is due to gilbert's syndrome or of non-hepatic origin; alanine aminotransferase/ aspartate aminotransferase (alt) >5*uln; prothrombin time (pt)/international normalized ratio (inr) >1.5*uln or activated partial thromboplastin time (aptt) >1.5*uln related to known coagulopathy or bleeding disorder (the participant can receive anticoagulant therapies for underlying conditions, or as systematic thromboprophylaxis due to covid-19, or as part of the treatment of complications of covid-19, but cannot participate in a clinical study with anticoagulants for covid-19) - pregnant or breastfeeding, unless in the opinion of the investigator, the benefit outweighs the risks - has active hepatitis b or c infection or has human immunodeficiency virus infection or acquired immune deficiency syndrome (hiv/aids) based on medical history and/or concomitant medication - known active or latent tuberculosis (tb), history of incompletely treated tb, suspected or known extrapulmonary tb based on medical history and/or concomitant medication - evidence of active bacterial (including but not limited to bacterial pneumonia), fungal, viral or opportunistic infection (other than sars-cov-2) - currently active clinically significant (example, causing hemodynamic instability and/or causing hypoxemia) and uncontrolled arrhythmia

- on invasive mechanical ventilation or on veno-venous ecmo for >48 hours at time of screening - received an investigational intervention (including investigational vaccines) or used an invasive investigational medical device within 30 days before the planned dose of study intervention. note: the investigator must ensure that the participant is not enrolled in another covid-19 study with an investigational intervention (apart from the exception specified below) prior to completion of day 28 of the current study. exception: participation in a single arm study, a non-blinded controlled study, expanded access, compassionate use program or any other program that is not a blinded study is allowed if it is conducted with one of the following: agents with demonstrated in vitro-effect against sarscov- 2, as mentioned in the center of disease control and prevention (cdc) guidelines and convalescent plasma - current confirmed or high suspicion for pulmonary embolus, hemodynamic significant pericardial effusion, myocarditis, or class 3 or 4 congestive heart failure as defined by the new york heart association functional classification and/or current evidence of active cardiac ischemia - has a history of respiratory condition (that is, asthma, chronic obstructive pulmonary disease (copd), cystic fibrosis, fibrotic lung disease) that requires home oxygen supplementation, supportive non-invasive ventilation or, is status/post lung volume reduction surgery (lvrs). exception: participants with sleep apnea using supportive non-invasive ventilation (continuous positive airway pressure [cpap]) at screening may be included - on renal replacement therapy (defined as peritoneal dialysis or hemodialysis) - screening laboratory test result as follows: absolute neutrophil count (anc) <1.0*10^3 cells/microliter; platelet count <50*10^3 cells/microliter; estimated glomerular filtration rate (egfr) <=30 milliliter per minute per 1.73 square meter (ml/min/1.73 m^2); bilirubin >2* upper limit of normal (uln) unless bilirubin rise is due to gilbert's syndrome or of non-hepatic origin; alanine aminotransferase/ aspartate aminotransferase (alt) >5*uln; prothrombin time (pt)/international normalized ratio (inr) >1.5*uln or activated partial thromboplastin time (aptt) >1.5*uln related to known coagulopathy or bleeding disorder (the participant can receive anticoagulant therapies for underlying conditions, or as systematic thromboprophylaxis due to covid-19, or as part of the treatment of complications of covid-19, but cannot participate in a clinical study with anticoagulants for covid-19) - pregnant or breastfeeding, unless in the opinion of the investigator, the benefit outweighs the risks - has active hepatitis b or c infection or human immunodeficiency virus infection or acquired immune deficiency syndrome (hiv/aids) based on medical history and/or concomitant medication - known active or latent tuberculosis (tb), history of incompletely treated tb, suspected or known extrapulmonary tb based on medical history and/or concomitant medication - evidence of active bacterial (including but not limited to bacterial pneumonia), fungal, viral or opportunistic infection (other than sars-cov-2) - currently active clinically significant (example, causing hemodynamic instability and/or causing hypoxemia) and uncontrolled arrhythmia

- on invasive mechanical ventilation or on veno-venous ecmo for >48 hours at time of screening - received an investigational intervention (including investigational vaccines) or used an invasive investigational medical device within 30 days before the planned dose of study intervention. note: the investigator must ensure that the participant is not enrolled in another covid-19 study with an investigational intervention (apart from the exception specified below) prior to completion of day 28 of the current study. exception: participation in a single arm study, a non-blinded controlled study, expanded access, compassionate use program or any other program that is not a blinded study is allowed if it is conducted with one of the following: agents with demonstrated in vitro-effect against sarscov- 2, as mentioned in the center of disease control and prevention (cdc) guidelines and convalescent plasma - current confirmed or high suspicion for pulmonary embolus, hemodynamic significant pericardial effusion, myocarditis, or class 3 or 4 congestive heart failure as defined by the new york heart association functional classification and/or current evidence of active cardiac ischemia - has a history of respiratory condition (that is, asthma, chronic obstructive pulmonary disease (copd), cystic fibrosis, fibrotic lung disease) that requires home oxygen supplementation, supportive non-invasive ventilation or, is status/post lung volume reduction surgery (lvrs). exception: participants with sleep apnea using supportive non-invasive ventilation (continuous positive airway pressure [cpap]) at screening may be included - on renal replacement therapy (defined as peritoneal dialysis or hemodialysis) - screening laboratory test result as follows: absolute neutrophil count (anc) <1.0*10^3 cells/microliter; platelet count <50*10^3 cells/microliter; estimated glomerular filtration rate (egfr) <=30 milliliter per minute per 1.73 square meter (ml/min/1.73 m^2); bilirubin >2* upper limit of normal (uln) unless bilirubin rise is due to gilbert's syndrome or of non-hepatic origin; alanine aminotransferase/ aspartate aminotransferase (alt) >5*uln; prothrombin time (pt)/international normalized ratio (inr) >1.5*uln or activated partial thromboplastin time (aptt) >1.5*uln related to known coagulopathy or bleeding disorder (the participant can receive anticoagulant therapies for underlying conditions, or as systematic thromboprophylaxis due to covid-19, or as part of the treatment of complications of covid-19, but cannot participate in a clinical study with anticoagulants for covid-19) - pregnant or breastfeeding, unless in the opinion of the investigator, the benefit outweighs the risks - has active hepatitis b or c infection or human immunodeficiency virus infection or acquired immune deficiency syndrome (hiv/aids) based on medical history and/or concomitant medication - known active or latent tuberculosis (tb), history of incompletely treated tb, suspected or known extrapulmonary tb based on medical history and/or concomitant medication - evidence of active bacterial (including but not limited to bacterial pneumonia), fungal, viral or opportunistic infection (other than sars-cov-2) - currently active clinically significant (example, causing hemodynamic instability and/or causing hypoxemia) and uncontrolled arrhythmia