* participation in any other randomized, controlled clinical trial of an experimental treatment for covid-19 (uncontrolled, compassionate use trials are allowed) * in the opinion of the investigator, progression to death is imminent and inevitable within the next 24 hours, irrespective of the provision of treatments * currently participating in a vaccination trial for sars-cov-2 * known positive test for influenza a or influenza b at the time of screening * positive for human immunodeficiency virus (hiv) that is not controlled with current treatment * hepatitis b surface antigen, or hepatitis c positive at the time of screening. subjects who are positive for hepatitis c but have hepatitis c virus (hcv) rna below the limit of quantitation may be enrolled. subjects with hepatitis b, but with undetectable viral load, may be enrolled. * alanine aminotransferase (alt) or aspartate aminotransferase (ast) \> 5 × the upper limit of normal (uln) * stage 4 severe chronic kidney disease (i.e., estimated glomerular filtration rate \[egfr\] \< 30 ml/min) or acute renal failure resulting in egfr \< 30 ml/min * serious comorbidity, including: 1. myocardial infarction (within the last month) 2. moderate or severe heart failure (new york heart association \[nyha\] class iii or iv) 3. acute stroke (within the last month) 4. uncontrolled malignancy. uncontrolled malignancy would include cancers that are not considered in remission, or solid tumor or hematological malignancies with evidence of disease progression in the past 3 months (i.e., there is evidence of disease progression by response evaluation criteria in solid tumours \[recist\] or equivalent relevant criterion for the type of malignancy), and are not considered effectively managed with ongoing treatment as determined by the investigator 5. recent severe thromboembolic disease or evidence of severe thromboembolic disease defined as a current large vessel thromboembolic event or a thromboembolic event within the past 3 months (e.g., deep vein thrombosis \[dvt\], pulmonary embolism, ischemic stroke, transient ischemic attack) requiring interventional treatment. this exclusion does not prohibit prophylaxis for thromboembolic events, including those considered possible with concurrent sars-cov-2 infection. * history of severe allergic or anaphylactic reactions or hypersensitivity to the study drug * consideration by the investigator, for any reason, that the subject is an unsuitable candidate to receive study treatment

* participation in any other randomized, controlled clinical trial of an experimental treatment for covid-19 (uncontrolled, compassionate use trials are allowed) * in the opinion of the investigator, progression to death is imminent and inevitable within the next 24 hours, irrespective of the provision of treatments * currently participating in a vaccination trial for sars-cov-2 * known positive test for influenza a or influenza b at the time of screening * positive for human immunodeficiency virus (hiv) that is not controlled with current treatment * hepatitis b surface antigen, or hepatitis c positive at the time of screening. subjects who are positive for hepatitis c but have hepatitis c virus (hcv) rna below the limit of quantitation may be enrolled. subjects with hepatitis b, but with undetectable viral load, may be enrolled. * alanine aminotransferase (alt) or aspartate aminotransferase (ast) \> 5 × the upper limit of normal (uln) * stage 4 severe chronic kidney disease (i.e., estimated glomerular filtration rate \[egfr\] \< 30 ml/min) or acute renal failure resulting in egfr \< 30 ml/min * serious comorbidity, including: 1. myocardial infarction (within the last month) 2. moderate or severe heart failure (new york heart association \[nyha\] class iii or iv) 3. acute stroke (within the last month) 4. uncontrolled malignancy. uncontrolled malignancy would include cancers that are not considered in remission, or solid tumor or hematological malignancies with evidence of disease progression in the past 3 months (i.e., there is evidence of disease progression by response evaluation criteria in solid tumours \[recist\] or equivalent relevant criterion for the type of malignancy), and are not considered effectively managed with ongoing treatment as determined by the investigator 5. recent severe thromboembolic disease or evidence of severe thromboembolic disease defined as a current large vessel thromboembolic event or a thromboembolic event within the past 3 months (e.g., deep vein thrombosis \[dvt\], pulmonary embolism, ischemic stroke, transient ischemic attack) requiring interventional treatment. this exclusion does not prohibit prophylaxis for thromboembolic events, including those considered possible with concurrent sars-cov-2 infection. * history of severe allergic or anaphylactic reactions or hypersensitivity to the study drug * consideration by the investigator, for any reason, that the subject is an unsuitable candidate to receive study treatment

participation in any other randomized, controlled clinical trial of an experimental treatment for covid-19 (uncontrolled, compassionate use trials are allowed) in the opinion of the investigator, progression to death is imminent and inevitable within the next 24 hours, irrespective of the provision of treatments currently participating in a vaccination trial for sars-cov-2 known positive test for influenza a or influenza b at the time of screening positive for human immunodeficiency virus (hiv) that is not controlled with current treatment hepatitis b surface antigen, or hepatitis c positive at the time of screening. subjects who are positive for hepatitis c but have hepatitis c virus (hcv) rna below the limit of quantitation may be enrolled. subjects with hepatitis b, but with undetectable viral load, may be enrolled. alanine aminotransferase (alt) or aspartate aminotransferase (ast) > 5 × the upper limit of normal (uln) stage 4 severe chronic kidney disease (i.e., estimated glomerular filtration rate [egfr] < 30 ml/min) or acute renal failure resulting in egfr < 30 ml/min serious comorbidity, including: myocardial infarction (within the last month) moderate or severe heart failure (new york heart association [nyha] class iii or iv) acute stroke (within the last month) uncontrolled malignancy. uncontrolled malignancy would include cancers that are not considered in remission, or solid tumor or hematological malignancies with evidence of disease progression in the past 3 months (i.e., there is evidence of disease progression by response evaluation criteria in solid tumours [recist] or equivalent relevant criterion for the type of malignancy), and are not considered effectively managed with ongoing treatment as determined by the investigator recent severe thromboembolic disease or evidence of severe thromboembolic disease defined as a current large vessel thromboembolic event or a thromboembolic event within the past 3 months (e.g., deep vein thrombosis [dvt], pulmonary embolism, ischemic stroke, transient ischemic attack) requiring interventional treatment. this exclusion does not prohibit prophylaxis for thromboembolic events, including those considered possible with concurrent sars-cov-2 infection. history of severe allergic or anaphylactic reactions or hypersensitivity to the study drug consideration by the investigator, for any reason, that the subject is an unsuitable candidate to receive study treatment

participation in any other randomized, controlled clinical trial of an experimental treatment for covid-19 (uncontrolled, compassionate use trials are allowed) in the opinion of the investigator, progression to death is imminent and inevitable within the next 24 hours, irrespective of the provision of treatments currently participating in a vaccination trial for sars-cov-2 known positive test for influenza a or influenza b at the time of screening positive for human immunodeficiency virus (hiv) that is not controlled with current treatment hepatitis b surface antigen, or hepatitis c positive at the time of screening. subjects who are positive for hepatitis c but have hepatitis c virus (hcv) rna below the limit of quantitation may be enrolled. subjects with hepatitis b, but with undetectable viral load, may be enrolled. alanine aminotransferase (alt) or aspartate aminotransferase (ast) > 5 × the upper limit of normal (uln) stage 4 severe chronic kidney disease (i.e., estimated glomerular filtration rate [egfr] < 30 ml/min) or acute renal failure resulting in egfr < 30 ml/min serious comorbidity, including: myocardial infarction (within the last month) moderate or severe heart failure (new york heart association [nyha] class iii or iv) acute stroke (within the last month) uncontrolled malignancy. uncontrolled malignancy would include cancers that are not considered in remission, or solid tumor or hematological malignancies with evidence of disease progression in the past 3 months (i.e., there is evidence of disease progression by response evaluation criteria in solid tumours [recist] or equivalent relevant criterion for the type of malignancy), and are not considered effectively managed with ongoing treatment as determined by the investigator recent severe thromboembolic disease or evidence of severe thromboembolic disease defined as a current large vessel thromboembolic event or a thromboembolic event within the past 3 months (e.g., deep vein thrombosis [dvt], pulmonary embolism, ischemic stroke, transient ischemic attack) requiring interventional treatment. this exclusion does not prohibit prophylaxis for thromboembolic events, including those considered possible with concurrent sars-cov-2 infection. history of severe allergic or anaphylactic reactions or hypersensitivity to the study drug consideration by the investigator, for any reason, that the subject is an unsuitable candidate to receive study treatment

participation in any other randomized, controlled clinical trial of an experimental treatment for covid-19 (uncontrolled, compassionate use trials are allowed) in the opinion of the investigator, progression to death is imminent and inevitable within the next 24 hours, irrespective of the provision of treatments currently participating in a vaccination trial for sars-cov-2 positive influenza test at screening positive for human immunodeficiency virus (hiv) that is not controlled with current treatment hepatitis b surface antigen, or hepatitis c positive at the time of screening. subjects who are positive for hepatitis c but have hepatitis c virus (hcv) rna below the limit of quantitation may be enrolled. subjects with hepatitis b, but with undetectable viral load, may be enrolled. alanine aminotransferase (alt) or aspartate aminotransferase (ast) > 5 × the upper limit of normal (uln) stage 4 severe chronic kidney disease (i.e., estimated glomerular filtration rate [egfr] < 30 ml/min) or acute renal failure resulting in egfr < 30 ml/min serious comorbidity, including: myocardial infarction (within the last month) moderate or severe heart failure (new york heart association [nyha] class iii or iv) acute stroke (within the last month) uncontrolled malignancy. uncontrolled malignancy would include cancers that are not considered in remission, or solid tumor or hematological malignancies with evidence of disease progression in the past 3 months (i.e., there is evidence of disease progression by response evaluation criteria in solid tumours [recist] or equivalent relevant criterion for the type of malignancy), and are not considered effectively managed with ongoing treatment as determined by the investigator recent severe thromboembolic disease or evidence of severe thromboembolic disease defined as a current large vessel thromboembolic event or a thromboembolic event within the past 3 months (e.g., deep vein thrombosis [dvt], pulmonary embolism, ischemic stroke, transient ischemic attack) requiring interventional treatment. this exclusion does not prohibit prophylaxis for thromboembolic events, including those considered possible with concurrent sars-cov-2 infection. history of severe allergic or anaphylactic reactions or hypersensitivity to the study drug consideration by the investigator, for any reason, that the subject is an unsuitable candidate to receive study treatment

participation in any other randomized, controlled clinical trial of an experimental treatment for covid-19 (uncontrolled, compassionate use trials are allowed) in the opinion of the investigator, progression to death is imminent and inevitable within the next 24 hours, irrespective of the provision of treatments currently participating in a vaccination trial for sars-cov-2 positive influenza test at screening positive for human immunodeficiency virus (hiv) that is not controlled with current treatment hepatitis b surface antigen, or hepatitis c positive at the time of screening. subjects who are positive for hepatitis c but have hepatitis c virus (hcv) rna below the limit of quantitation may be enrolled. subjects with hepatitis b, but with undetectable viral load, may be enrolled. alanine aminotransferase (alt) or aspartate aminotransferase (ast) > 5 × the upper limit of normal (uln) stage 4 severe chronic kidney disease (i.e., estimated glomerular filtration rate [egfr] < 30 ml/min) or acute renal failure resulting in egfr < 30 ml/min serious comorbidity, including: myocardial infarction (within the last month) moderate or severe heart failure (new york heart association [nyha] class iii or iv) acute stroke (within the last month) uncontrolled malignancy. uncontrolled malignancy would include cancers that are not considered in remission, or solid tumor or hematological malignancies with evidence of disease progression in the past 3 months (i.e., there is evidence of disease progression by response evaluation criteria in solid tumours [recist] or equivalent relevant criterion for the type of malignancy), and are not considered effectively managed with ongoing treatment as determined by the investigator recent severe thromboembolic disease or evidence of severe thromboembolic disease defined as a current large vessel thromboembolic event or a thromboembolic event within the past 3 months (e.g., deep vein thrombosis [dvt], pulmonary embolism, ischemic stroke, transient ischemic attack) requiring interventional treatment. this exclusion does not prohibit prophylaxis for thromboembolic events, including those considered possible with concurrent sars-cov-2 infection. history of severe allergic or anaphylactic reactions or hypersensitivity to the study drug consideration by the investigator, for any reason, that the subject is an unsuitable candidate to receive study treatment

- participation in any other randomized, controlled clinical trial of an experimental treatment for covid-19 (uncontrolled, compassionate use trials are allowed) - in the opinion of the investigator, progression to death is imminent and inevitable within the next 24 hours, irrespective of the provision of treatments - currently participating in a vaccination trial for sars-cov-2 - positive influenza test at screening - positive for human immunodeficiency virus (hiv) that is not controlled with current treatment - hepatitis b surface antigen, or hepatitis c positive at the time of screening. subjects who are positive for hepatitis c but have hepatitis c virus (hcv) rna below the limit of quantitation may be enrolled. subjects with hepatitis b, but with undetectable viral load, may be enrolled. - alanine aminotransferase (alt) or aspartate aminotransferase (ast) > 5 × the upper limit of normal (uln) - stage 4 severe chronic kidney disease (i.e., estimated glomerular filtration rate [egfr] < 30 ml/min) or acute renal failure resulting in egfr < 30 ml/min - serious comorbidity, including: 1. myocardial infarction (within the last month) 2. moderate or severe heart failure (new york heart association [nyha] class iii or iv) 3. acute stroke (within the last month) 4. uncontrolled malignancy. uncontrolled malignancy would include cancers that are not considered in remission, or solid tumor or hematological malignancies with evidence of disease progression in the past 3 months (i.e., there is evidence of disease progression by response evaluation criteria in solid tumours [recist] or equivalent relevant criterion for the type of malignancy), and are not considered effectively managed with ongoing treatment as determined by the investigator 5. recent severe thromboembolic disease or evidence of severe thromboembolic disease defined as a current large vessel thromboembolic event or a thromboembolic event within the past 3 months (e.g., deep vein thrombosis [dvt], pulmonary embolism, ischemic stroke, transient ischemic attack) requiring interventional treatment. this exclusion does not prohibit prophylaxis for thromboembolic events, including those considered possible with concurrent sars-cov-2 infection. - history of severe allergic or anaphylactic reactions or hypersensitivity to the study drug - consideration by the investigator, for any reason, that the subject is an unsuitable candidate to receive study treatment

- participation in any other randomized, controlled clinical trial of an experimental treatment for covid-19 (uncontrolled, compassionate use trials are allowed) - in the opinion of the investigator, progression to death is imminent and inevitable within the next 24 hours, irrespective of the provision of treatments - currently participating in a vaccination trial for sars-cov-2 - positive influenza test at screening - positive for human immunodeficiency virus (hiv) that is not controlled with current treatment - hepatitis b surface antigen, or hepatitis c positive at the time of screening. subjects who are positive for hepatitis c but have hepatitis c virus (hcv) rna below the limit of quantitation may be enrolled. subjects with hepatitis b, but with undetectable viral load, may be enrolled. - alanine aminotransferase (alt) or aspartate aminotransferase (ast) > 5 × the upper limit of normal (uln) - stage 4 severe chronic kidney disease (i.e., estimated glomerular filtration rate [egfr] < 30 ml/min) or acute renal failure resulting in egfr < 30 ml/min - serious comorbidity, including: 1. myocardial infarction (within the last month) 2. moderate or severe heart failure (new york heart association [nyha] class iii or iv) 3. acute stroke (within the last month) 4. uncontrolled malignancy. uncontrolled malignancy would include cancers that are not considered in remission, or solid tumor or hematological malignancies with evidence of disease progression in the past 3 months (i.e., there is evidence of disease progression by response evaluation criteria in solid tumours [recist] or equivalent relevant criterion for the type of malignancy), and are not considered effectively managed with ongoing treatment as determined by the investigator 5. recent severe thromboembolic disease or evidence of severe thromboembolic disease defined as a current large vessel thromboembolic event or a thromboembolic event within the past 3 months (e.g., deep vein thrombosis [dvt], pulmonary embolism, ischemic stroke, transient ischemic attack) requiring interventional treatment. this exclusion does not prohibit prophylaxis for thromboembolic events, including those considered possible with concurrent sars-cov-2 infection. - history of severe allergic or anaphylactic reactions or hypersensitivity to the study drug - consideration by the investigator, for any reason, that the subject is an unsuitable candidate to receive study treatment

- participation in any other randomized, controlled clinical trial of an experimental treatment for covid-19 (uncontrolled, compassionate use trials are allowed) - in the opinion of the investigator, progression to death is imminent and inevitable within the next 24 hours, irrespective of the provision of treatments - currently participating in a vaccination trial for sars-cov-2 - subject requires oxygen administration by high flow nasal cannula (> 20 l/min) - positive influenza test at screening - positive for human immunodeficiency virus (hiv) that is not controlled with current treatment - hepatitis b surface antigen, or hepatitis c positive at the time of screening. subjects who are positive for hepatitis c but have hepatitis c virus (hcv) rna below the limit of quantitation may be enrolled. subjects with hepatitis b, but with undetectable viral load, may be enrolled. - alanine aminotransferase (alt) or aspartate aminotransferase (ast) > 5 × the upper limit of normal (uln) - stage 4 severe chronic kidney disease (i.e., estimated glomerular filtration rate [egfr] < 30 ml/min) or acute renal failure resulting in egfr < 30 ml/min - serious comorbidity, including: 1. myocardial infarction (within the last month) 2. moderate or severe heart failure (new york heart association [nyha] class iii or iv) 3. acute stroke (within the last month) 4. uncontrolled malignancy. uncontrolled malignancy would include cancers that are not considered in remission, or solid tumor or hematological malignancies with evidence of disease progression in the past 3 months (i.e., there is evidence of disease progression by response evaluation criteria in solid tumours [recist] or equivalent relevant criterion for the type of malignancy), and are not considered effectively managed with ongoing treatment as determined by the investigator 5. recent severe thromboembolic disease or evidence of severe thromboembolic disease defined as a current large vessel thromboembolic event or a thromboembolic event within the past 3 months (e.g., deep vein thrombosis [dvt], pulmonary embolism, ischemic stroke, transient ischemic attack) requiring interventional treatment. this exclusion does not prohibit prophylaxis for thromboembolic events, including those considered possible with concurrent sars-cov-2 infection. - history of severe allergic or anaphylactic reactions or hypersensitivity to the study drug - consideration by the investigator, for any reason, that the subject is an unsuitable candidate to receive study treatment

- participation in any other randomized, controlled clinical trial of an experimental treatment for covid-19 (uncontrolled, compassionate use trials are allowed) - in the opinion of the investigator, progression to death is imminent and inevitable within the next 24 hours, irrespective of the provision of treatments - currently participating in a vaccination trial for sars-cov-2 - subject requires oxygen administration by high flow nasal cannula (> 20 l/min) - positive influenza test at screening - positive for human immunodeficiency virus (hiv) that is not controlled with current treatment - hepatitis b surface antigen, or hepatitis c positive at the time of screening. subjects who are positive for hepatitis c but have hepatitis c virus (hcv) rna below the limit of quantitation may be enrolled. subjects with hepatitis b, but with undetectable viral load, may be enrolled. - alanine aminotransferase (alt) or aspartate aminotransferase (ast) > 5 × the upper limit of normal (uln) - stage 4 severe chronic kidney disease (i.e., estimated glomerular filtration rate [egfr] < 30 ml/min) or acute renal failure resulting in egfr < 30 ml/min - serious comorbidity, including: 1. myocardial infarction (within the last month) 2. moderate or severe heart failure (new york heart association [nyha] class iii or iv) 3. acute stroke (within the last month) 4. uncontrolled malignancy. uncontrolled malignancy would include cancers that are not considered in remission, or solid tumor or hematological malignancies with evidence of disease progression in the past 3 months (i.e., there is evidence of disease progression by response evaluation criteria in solid tumours [recist] or equivalent relevant criterion for the type of malignancy), and are not considered effectively managed with ongoing treatment as determined by the investigator 5. recent severe thromboembolic disease or evidence of severe thromboembolic disease defined as a current large vessel thromboembolic event or a thromboembolic event within the past 3 months (e.g., deep vein thrombosis [dvt], pulmonary embolism, ischemic stroke, transient ischemic attack) requiring interventional treatment. this exclusion does not prohibit prophylaxis for thromboembolic events, including those considered possible with concurrent sars-cov-2 infection. - history of severe allergic or anaphylactic reactions or hypersensitivity to the study drug - consideration by the investigator, for any reason, that the subject is an unsuitable candidate to receive study treatment

- participation in any other randomized, controlled clinical trial of an experimental treatment for covid-19 (uncontrolled, compassionate use trials are allowed) - in the opinion of the investigator, progression to death is imminent and inevitable within the next 24 hours, irrespective of the provision of treatments - currently participating in a vaccination trial for sars-cov-2 - subject requires oxygen administration by high flow nasal cannula (> 20 l/min) - positive influenza test at screening - positive for human immunodeficiency virus (hiv) that is not controlled with current treatment - hepatitis b surface antigen, or hepatitis c positive at the time of screening. subjects who are positive for hepatitis c but have hepatitis c virus (hcv) rna below the limit of quantitation may be enrolled. subjects with hepatitis b, but with undetectable viral load, may be enrolled. - alanine aminotransferase (alt) or aspartate aminotransferase (ast) > 5 × the upper limit of normal (uln) - stage 4 severe chronic kidney disease (i.e., estimated glomerular filtration rate [egfr] < 30 ml/min) or acute renal failure resulting in egfr < 30 ml/min - serious comorbidity, including: 1. myocardial infarction (within the last month) 2. moderate or severe heart failure (new york heart association [nyha] class iii or iv) 3. acute stroke (within the last month) 4. uncontrolled malignancy. uncontrolled malignancy would include cancers that are not considered in remission, or solid tumor or hematological malignancies with evidence of disease progression in the past 3 months (i.e., there is evidence disease progression by response evaluation criteria in solid tumours [recist] or equivalent relevant criterion for the type of malignancy), and are not considered effectively managed with ongoing treatment as determined by the investigator 5. recent severe thromboembolic disease or evidence of severe thromboembolic disease defined as a current large vessel thromboembolic event or a thromboembolic event within the past 3 months (e.g., deep vein thrombosis [dvt], pulmonary embolism, ischemic stroke, transient ischemic attack) requiring interventional treatment. this exclusion does not prohibit prophylaxis for thromboembolic events, including those considered possible with concurrent sars-cov-2 infection. - history of severe allergic or anaphylactic reactions or hypersensitivity to the study drug - consideration by the investigator, for any reason, that the subject is an unsuitable candidate to receive study treatment

- participation in any other randomized, controlled clinical trial of an experimental treatment for covid-19 (uncontrolled, compassionate use trials are allowed) - in the opinion of the investigator, progression to death is imminent and inevitable within the next 24 hours, irrespective of the provision of treatments - currently participating in a vaccination trial for sars-cov-2 - subject requires oxygen administration by high flow nasal cannula (> 20 l/min) - positive influenza test at screening - positive for human immunodeficiency virus (hiv) that is not controlled with current treatment - hepatitis b surface antigen, or hepatitis c positive at the time of screening. subjects who are positive for hepatitis c but have hepatitis c virus (hcv) rna below the limit of quantitation may be enrolled. subjects with hepatitis b, but with undetectable viral load, may be enrolled. - alanine aminotransferase (alt) or aspartate aminotransferase (ast) > 5 × the upper limit of normal (uln) - stage 4 severe chronic kidney disease (i.e., estimated glomerular filtration rate [egfr] < 30 ml/min) or acute renal failure resulting in egfr < 30 ml/min - serious comorbidity, including: 1. myocardial infarction (within the last month) 2. moderate or severe heart failure (new york heart association [nyha] class iii or iv) 3. acute stroke (within the last month) 4. uncontrolled malignancy. uncontrolled malignancy would include cancers that are not considered in remission, or solid tumor or hematological malignancies with evidence of disease progression in the past 3 months (i.e., there is evidence disease progression by response evaluation criteria in solid tumours [recist] or equivalent relevant criterion for the type of malignancy), and are not considered effectively managed with ongoing treatment as determined by the investigator 5. recent severe thromboembolic disease or evidence of severe thromboembolic disease defined as a current large vessel thromboembolic event or a thromboembolic event within the past 3 months (e.g., deep vein thrombosis [dvt], pulmonary embolism, ischemic stroke, transient ischemic attack) requiring interventional treatment. this exclusion does not prohibit prophylaxis for thromboembolic events, including those considered possible with concurrent sars-cov-2 infection. - history of severe allergic or anaphylactic reactions or hypersensitivity to the study drug - consideration by the investigator, for any reason, that the subject is an unsuitable candidate to receive study treatment