1. intubated and on invasive mechanical ventilation for three or more days at the time of randomization 2. known left ventricular ejection fraction (lvef) \<40% or prior hospitalization for heart failure 3. cardiac arrest 4. shock 5. known uncontrolled bacterial, fungal, or non-covid viral infection 6. egfr \<30 ml/min/1.73 m² or requiring dialysis 7. alt or ast \> 5x uln 8. history of cirrhosis, chronic active hepatitis or severe hepatic disease 9. pregnant or lactating women 10. enrolled in other trial of unapproved therapies, unless approved by trial principal investigator. in general, co-enrollment will be permitted unless there are safety concerns, mechanistic incompatibility or inability to adjudicate serious adverse events and will be decided on a case by case basis. 11. if in the opinion of the clinical team, progression to death is imminent and inevitable within the next 24 hours, irrespective of the provision of treatments

1. intubated and on invasive mechanical ventilation for three or more days at the time of randomization 2. known left ventricular ejection fraction (lvef) \<40% or prior hospitalization for heart failure 3. cardiac arrest 4. shock 5. known uncontrolled bacterial, fungal, or non-covid viral infection 6. egfr \<30 ml/min/1.73 m² or requiring dialysis 7. alt or ast \> 5x uln 8. history of cirrhosis, chronic active hepatitis or severe hepatic disease 9. pregnant or lactating women 10. enrolled in other trial of unapproved therapies, unless approved by trial principal investigator. in general, co-enrollment will be permitted unless there are safety concerns, mechanistic incompatibility or inability to adjudicate serious adverse events and will be decided on a case by case basis. 11. if in the opinion of the clinical team, progression to death is imminent and inevitable within the next 24 hours, irrespective of the provision of treatments

intubated and on invasive mechanical ventilation for three or more days at the time of randomization known left ventricular ejection fraction (lvef) <40% or prior hospitalization for heart failure cardiac arrest shock known uncontrolled bacterial, fungal, or non-covid viral infection egfr <30 ml/min/1.73 m² or requiring dialysis alt or ast > 5x uln history of cirrhosis, chronic active hepatitis or severe hepatic disease pregnant or lactating women enrolled in other trial of unapproved therapies, unless approved by trial principal investigator. in general, co-enrollment will be permitted unless there are safety concerns, mechanistic incompatibility or inability to adjudicate serious adverse events and will be decided on a case by case basis. if in the opinion of the clinical team, progression to death is imminent and inevitable within the next 24 hours, irrespective of the provision of treatments

intubated and on invasive mechanical ventilation for three or more days at the time of randomization known left ventricular ejection fraction (lvef) <40% or prior hospitalization for heart failure cardiac arrest shock known uncontrolled bacterial, fungal, or non-covid viral infection egfr <30 ml/min/1.73 m² or requiring dialysis alt or ast > 5x uln history of cirrhosis, chronic active hepatitis or severe hepatic disease pregnant or lactating women enrolled in other trial of unapproved therapies, unless approved by trial principal investigator. in general, co-enrollment will be permitted unless there are safety concerns, mechanistic incompatibility or inability to adjudicate serious adverse events and will be decided on a case by case basis. if in the opinion of the clinical team, progression to death is imminent and inevitable within the next 24 hours, irrespective of the provision of treatments

1. intubated and on invasive mechanical ventilation for three or more days at the time of randomization 2. known left ventricular ejection fraction (lvef) <40% or prior hospitalization for heart failure 3. cardiac arrest 4. shock 5. known uncontrolled bacterial, fungal, or non-covid viral infection 6. egfr <30 ml/min/1.73 m² or requiring dialysis 7. alt or ast > 5x uln 8. history of cirrhosis, chronic active hepatitis or severe hepatic disease 9. pregnant or lactating women 10. enrolled in other trial of unapproved therapies, unless approved by trial principal investigator. in general, co-enrollment will be permitted unless there are safety concerns, mechanistic incompatibility or inability to adjudicate serious adverse events and will be decided on a case by case basis. 11. if in the opinion of the clinical team, progression to death is imminent and inevitable within the next 24 hours, irrespective of the provision of treatments

1. intubated and on invasive mechanical ventilation for three or more days at the time of randomization 2. known left ventricular ejection fraction (lvef) <40% or prior hospitalization for heart failure 3. cardiac arrest 4. shock 5. known uncontrolled bacterial, fungal, or non-covid viral infection 6. egfr <30 ml/min/1.73 m² or requiring dialysis 7. alt or ast > 5x uln 8. history of cirrhosis, chronic active hepatitis or severe hepatic disease 9. pregnant or lactating women 10. enrolled in other trial of unapproved therapies, unless approved by trial principal investigator. in general, co-enrollment will be permitted unless there are safety concerns, mechanistic incompatibility or inability to adjudicate serious adverse events and will be decided on a case by case basis. 11. if in the opinion of the clinical team, progression to death is imminent and inevitable within the next 24 hours, irrespective of the provision of treatments