* has critical covid-19 with any of the following: respiratory failure (including endotracheal intubation and mechanical ventilation, oxygen delivered by high-flow nasal cannula (flow rates \>20l/min with fraction of delivered oxygen ≥ 0.5), noninvasive positive pressure ventilation, or extracorporeal membrane oxygenation (ecmo)) * is on dialysis or has reduced estimated glomerular filtration rate (egfr) \<30 ml/min/1.73m\^2 by the modification of diet in renal disease (mdrd) equation * has any of the following conditions: human immunodeficiency virus (hiv) with a recent viral load \>50 copies/ml or cluster of differentiation 4 (cd4) \<200 cell/mm\^3; chemotherapy required within 6 weeks before randomization; a neutrophilic granulocyte absolute count \<500/mm\^3; autologous or allogeneic hematopoietic stem cell transplant recipient * has history of hepatitis b or hepatitis c infection with any of the following: 1) cirrhosis 2) end-stage liver disease 3) hepatocellular carcinoma 4) aspartate aminotransferase (ast) and/or alanine aminotransferase (alt) \> 3 times the upper limit of normal at screening * has a history of acute pancreatitis within 3 months prior to randomization or a history of chronic pancreatitis * is taking or is anticipated to require any prohibited therapies * is unwilling to abstain from participating in another interventional clinical trial through day 29 with an investigational compound or device, including those for covid-19 therapeutics * is anticipated to require transfer to a non-study hospital within 72 hours * has a baseline heart rate of \< 50 beats per minute at rest * has a platelet count \<100,000/μl or received a platelet transfusion in the 5 days prior to randomization * has hypersensitivity or other contraindication to any of the components of the study interventions as determined by the investigator * has any condition for which, in the opinion of the investigator, participation would not be in the best interest of the participant or that could prevent, limit, or confound the protocol-specified assessments including but not limited to: participants who are not expected to survive longer than 48 hours after randomization or participants who are expected to require mechanical ventilation within 48 hours after randomization or participants with a recent history of mechanical ventilation or participants with conditions that could limit gastrointestinal absorption of capsule contents

* has critical covid-19 with any of the following: respiratory failure (including endotracheal intubation and mechanical ventilation, oxygen delivered by high-flow nasal cannula (flow rates \>20l/min with fraction of delivered oxygen ≥ 0.5), noninvasive positive pressure ventilation, or extracorporeal membrane oxygenation (ecmo)) * is on dialysis or has reduced estimated glomerular filtration rate (egfr) \<30 ml/min/1.73m\^2 by the modification of diet in renal disease (mdrd) equation * has any of the following conditions: human immunodeficiency virus (hiv) with a recent viral load \>50 copies/ml or cluster of differentiation 4 (cd4) \<200 cell/mm\^3; chemotherapy required within 6 weeks before randomization; a neutrophilic granulocyte absolute count \<500/mm\^3; autologous or allogeneic hematopoietic stem cell transplant recipient * has history of hepatitis b or hepatitis c infection with any of the following: 1) cirrhosis 2) end-stage liver disease 3) hepatocellular carcinoma 4) aspartate aminotransferase (ast) and/or alanine aminotransferase (alt) \> 3 times the upper limit of normal at screening * has a history of acute pancreatitis within 3 months prior to randomization or a history of chronic pancreatitis * is taking or is anticipated to require any prohibited therapies * is unwilling to abstain from participating in another interventional clinical trial through day 29 with an investigational compound or device, including those for covid-19 therapeutics * is anticipated to require transfer to a non-study hospital within 72 hours * has a baseline heart rate of \< 50 beats per minute at rest * has a platelet count \<100,000/μl or received a platelet transfusion in the 5 days prior to randomization * has hypersensitivity or other contraindication to any of the components of the study interventions as determined by the investigator * has any condition for which, in the opinion of the investigator, participation would not be in the best interest of the participant or that could prevent, limit, or confound the protocol-specified assessments including but not limited to: participants who are not expected to survive longer than 48 hours after randomization or participants who are expected to require mechanical ventilation within 48 hours after randomization or participants with a recent history of mechanical ventilation or participants with conditions that could limit gastrointestinal absorption of capsule contents

has critical covid-19 with any of the following: respiratory failure (including endotracheal intubation and mechanical ventilation, oxygen delivered by high-flow nasal cannula (flow rates >20l/min with fraction of delivered oxygen ≥ 0.5), noninvasive positive pressure ventilation, or extracorporeal membrane oxygenation (ecmo)) is on dialysis or has reduced estimated glomerular filtration rate (egfr) <30 ml/min/1.73m^2 by the modification of diet in renal disease (mdrd) equation has any of the following conditions: human immunodeficiency virus (hiv) with a recent viral load >50 copies/ml or cluster of differentiation 4 (cd4) <200 cell/mm^3; chemotherapy required within 6 weeks before randomization; a neutrophilic granulocyte absolute count <500/mm^3; autologous or allogeneic hematopoietic stem cell transplant recipient has history of hepatitis b or hepatitis c infection with any of the following: 1) cirrhosis 2) end-stage liver disease 3) hepatocellular carcinoma 4) aspartate aminotransferase (ast) and/or alanine aminotransferase (alt) > 3 times the upper limit of normal at screening has a history of acute pancreatitis within 3 months prior to randomization or a history of chronic pancreatitis is taking or is anticipated to require any prohibited therapies is unwilling to abstain from participating in another interventional clinical trial through day 29 with an investigational compound or device, including those for covid-19 therapeutics is anticipated to require transfer to a non-study hospital within 72 hours has a baseline heart rate of < 50 beats per minute at rest has a platelet count <100,000/μl or received a platelet transfusion in the 5 days prior to randomization has hypersensitivity or other contraindication to any of the components of the study interventions as determined by the investigator has any condition for which, in the opinion of the investigator, participation would not be in the best interest of the participant or that could prevent, limit, or confound the protocol-specified assessments including but not limited to: participants who are not expected to survive longer than 48 hours after randomization or participants who are expected to require mechanical ventilation within 48 hours after randomization or participants with a recent history of mechanical ventilation or participants with conditions that could limit gastrointestinal absorption of capsule contents

has critical covid-19 with any of the following: respiratory failure (including endotracheal intubation and mechanical ventilation, oxygen delivered by high-flow nasal cannula (flow rates >20l/min with fraction of delivered oxygen ≥ 0.5), noninvasive positive pressure ventilation, or extracorporeal membrane oxygenation (ecmo)) is on dialysis or has reduced estimated glomerular filtration rate (egfr) <30 ml/min/1.73m^2 by the modification of diet in renal disease (mdrd) equation has any of the following conditions: human immunodeficiency virus (hiv) with a recent viral load >50 copies/ml or cluster of differentiation 4 (cd4) <200 cell/mm^3; chemotherapy required within 6 weeks before randomization; a neutrophilic granulocyte absolute count <500/mm^3; autologous or allogeneic hematopoietic stem cell transplant recipient has history of hepatitis b or hepatitis c infection with any of the following: 1) cirrhosis 2) end-stage liver disease 3) hepatocellular carcinoma 4) aspartate aminotransferase (ast) and/or alanine aminotransferase (alt) > 3 times the upper limit of normal at screening has a history of acute pancreatitis within 3 months prior to randomization or a history of chronic pancreatitis is taking or is anticipated to require any prohibited therapies is unwilling to abstain from participating in another interventional clinical trial through day 29 with an investigational compound or device, including those for covid-19 therapeutics is anticipated to require transfer to a non-study hospital within 72 hours has a baseline heart rate of < 50 beats per minute at rest has a platelet count <100,000/μl or received a platelet transfusion in the 5 days prior to randomization has hypersensitivity or other contraindication to any of the components of the study interventions as determined by the investigator has any condition for which, in the opinion of the investigator, participation would not be in the best interest of the participant or that could prevent, limit, or confound the protocol-specified assessments including but not limited to: participants who are not expected to survive longer than 48 hours after randomization or participants who are expected to require mechanical ventilation within 48 hours after randomization or participants with a recent history of mechanical ventilation or participants with conditions that could limit gastrointestinal absorption of capsule contents

- has critical covid-19 with any of the following: respiratory failure (including endotracheal intubation and mechanical ventilation, oxygen delivered by high-flow nasal cannula (flow rates >20l/min with fraction of delivered oxygen >= 0.5), noninvasive positive pressure ventilation, or extracorporeal membrane oxygenation (ecmo)) - is on dialysis or has reduced estimated glomerular filtration rate (egfr) <30 ml/min/1.73m^2 by the modification of diet in renal disease (mdrd) equation - has any of the following conditions: human immunodeficiency virus (hiv) with a recent viral load >50 copies/ml or cluster of differentiation 4 (cd4) <200 cell/mm^3; chemotherapy required within 6 weeks before randomization; a neutrophilic granulocyte absolute count <500/mm^3; autologous or allogeneic hematopoietic stem cell transplant recipient - has history of hepatitis b or hepatitis c infection with any of the following: 1) cirrhosis 2) end-stage liver disease 3) hepatocellular carcinoma 4) aspartate aminotransferase (ast) and/or alanine aminotransferase (alt) > 3 times the upper limit of normal at screening - has a history of acute pancreatitis within 3 months prior to randomization or a history of chronic pancreatitis - is taking or is anticipated to require any prohibited therapies - is unwilling to abstain from participating in another interventional clinical trial through day 29 with an investigational compound or device, including those for covid-19 therapeutics - is anticipated to require transfer to a non-study hospital within 72 hours - has a baseline heart rate of < 50 beats per minute at rest - has a platelet count <100,000/μl or received a platelet transfusion in the 5 days prior to randomization - has hypersensitivity or other contraindication to any of the components of the study interventions as determined by the investigator - has any condition for which, in the opinion of the investigator, participation would not be in the best interest of the participant or that could prevent, limit, or confound the protocol-specified assessments including but not limited to: participants who are not expected to survive longer than 48 hours after randomization or participants who are expected to require mechanical ventilation within 48 hours after randomization or participants with a recent history of mechanical ventilation or participants with conditions that could limit gastrointestinal absorption of capsule contents

- has critical covid-19 with any of the following: respiratory failure (including endotracheal intubation and mechanical ventilation, oxygen delivered by high-flow nasal cannula (flow rates >20l/min with fraction of delivered oxygen >= 0.5), noninvasive positive pressure ventilation, or extracorporeal membrane oxygenation (ecmo)) - is on dialysis or has reduced estimated glomerular filtration rate (egfr) <30 ml/min/1.73m^2 by the modification of diet in renal disease (mdrd) equation - has any of the following conditions: human immunodeficiency virus (hiv) with a recent viral load >50 copies/ml or cluster of differentiation 4 (cd4) <200 cell/mm^3; chemotherapy required within 6 weeks before randomization; a neutrophilic granulocyte absolute count <500/mm^3; autologous or allogeneic hematopoietic stem cell transplant recipient - has history of hepatitis b or hepatitis c infection with any of the following: 1) cirrhosis 2) end-stage liver disease 3) hepatocellular carcinoma 4) aspartate aminotransferase (ast) and/or alanine aminotransferase (alt) > 3 times the upper limit of normal at screening - has a history of acute pancreatitis within 3 months prior to randomization or a history of chronic pancreatitis - is taking or is anticipated to require any prohibited therapies - is unwilling to abstain from participating in another interventional clinical trial through day 29 with an investigational compound or device, including those for covid-19 therapeutics - is anticipated to require transfer to a non-study hospital within 72 hours - has a baseline heart rate of < 50 beats per minute at rest - has a platelet count <100,000/μl or received a platelet transfusion in the 5 days prior to randomization - has hypersensitivity or other contraindication to any of the components of the study interventions as determined by the investigator - has any condition for which, in the opinion of the investigator, participation would not be in the best interest of the participant or that could prevent, limit, or confound the protocol-specified assessments including but not limited to: participants who are not expected to survive longer than 48 hours after randomization or participants who are expected to require mechanical ventilation within 48 hours after randomization or participants with a recent history of mechanical ventilation or participants with conditions that could limit gastrointestinal absorption of capsule contents

- has critical covid-19 with any of the following: respiratory failure (including endotracheal intubation and mechanical ventilation, oxygen delivered by high-flow nasal cannula (flow rates >20l/min with fraction of delivered oxygen >= 0.5), noninvasive positive pressure ventilation, or extracorporeal membrane oxygenation (ecmo)) - is on dialysis or has reduced estimated glomerular filtration rate (egfr) <30 ml/min/1.73m^2 by the modification of diet in renal disease (mdrd) equation - has any of the following conditions: human immunodeficiency virus (hiv) with a recent viral load >50 copies/ml or cluster of differentiation 4 (cd4) <200 cell/mm^3; chemotherapy required within 6 weeks before randomization; a neutrophilic granulocyte absolute count <500/mm^3; autologous or allogeneic hematopoietic stem cell transplant recipient - has an active diagnosis of hepatitis due to any cause - has a history of acute pancreatitis within 3 months prior to randomization or a history of chronic pancreatitis - is taking or is anticipated to require any prohibited therapies - is unwilling to abstain from participating in another interventional clinical trial through day 29 with an investigational compound or device, including those for covid-19 therapeutics - is anticipated to require transfer to a non-study hospital within 72 hours - has a baseline heart rate of < 50 beats per minute at rest - has a platelet count <100,000/μl or received a platelet transfusion in the 5 days prior to randomization. - has hypersensitivity or other contraindication to any of the components of the study interventions as determined by the investigator - has any condition for which, in the opinion of the investigator, participation would not be in the best interest of the participant or that could prevent, limit, or confound the protocol-specified assessments including but not limited to: participants who are not expected to survive longer than 48 hours after randomization, participants who are expected to require mechanical ventilation within 48 hours after randomization, or participants with a recent history of mechanical ventilation not associated with covid-19, or participants with conditions that could limit gastrointestinal absorption of capsule contents.

- has critical covid-19 with any of the following: respiratory failure (including endotracheal intubation and mechanical ventilation, oxygen delivered by high-flow nasal cannula (flow rates >20l/min with fraction of delivered oxygen >= 0.5), noninvasive positive pressure ventilation, or extracorporeal membrane oxygenation (ecmo)) - is on dialysis or has reduced estimated glomerular filtration rate (egfr) <30 ml/min/1.73m^2 by the modification of diet in renal disease (mdrd) equation - has any of the following conditions: human immunodeficiency virus (hiv) with a recent viral load >50 copies/ml or cluster of differentiation 4 (cd4) <200 cell/mm^3; chemotherapy required within 6 weeks before randomization; a neutrophilic granulocyte absolute count <500/mm^3; autologous or allogeneic hematopoietic stem cell transplant recipient - has an active diagnosis of hepatitis due to any cause - has a history of acute pancreatitis within 3 months prior to randomization or a history of chronic pancreatitis - is taking or is anticipated to require any prohibited therapies - is unwilling to abstain from participating in another interventional clinical trial through day 29 with an investigational compound or device, including those for covid-19 therapeutics - is anticipated to require transfer to a non-study hospital within 72 hours - has a baseline heart rate of < 50 beats per minute at rest - has a platelet count <100,000/μl or received a platelet transfusion in the 5 days prior to randomization. - has hypersensitivity or other contraindication to any of the components of the study interventions as determined by the investigator - has any condition for which, in the opinion of the investigator, participation would not be in the best interest of the participant or that could prevent, limit, or confound the protocol-specified assessments including but not limited to: participants who are not expected to survive longer than 48 hours after randomization, participants who are expected to require mechanical ventilation within 48 hours after randomization, or participants with a recent history of mechanical ventilation not associated with covid-19, or participants with conditions that could limit gastrointestinal absorption of capsule contents.