inclusion criteria: * age ≥ 18 years * willing and able to provide written informed consent prior to performing study procedures * severe acute respiratory syndrome coronavirus (sars-cov)-2 infection confirmed by polymerase chain reaction (pcr) test ≤ 5 days before randomization or clinical presentation consistent with covid-19 infection (fever or cough or shortness of breath) with positive igm serology * currently hospitalized or in an emergency department * peripheral capillary oxygen saturation (spo2) ≥ 93% on room air at screening

inclusion criteria: * age ≥ 18 years * willing and able to provide written informed consent prior to performing study procedures * severe acute respiratory syndrome coronavirus (sars-cov)-2 infection confirmed by polymerase chain reaction (pcr) test ≤ 5 days before randomization or clinical presentation consistent with covid-19 infection (fever or cough or shortness of breath) with positive igm serology * currently hospitalized or in an emergency department * peripheral capillary oxygen saturation (spo2) ≥ 93% on room air at screening

inclusion criteria: - age ≥ 18 years - willing and able to provide written informed consent prior to performing study procedures - severe acute respiratory syndrome coronavirus (sars-cov)-2 infection confirmed by polymerase chain reaction (pcr) test ≤ 5 days before randomization or clinical presentation consistent with covid-19 infection (fever or cough or shortness of breath) with positive igm serology - currently hospitalized or in an emergency department - peripheral capillary oxygen saturation (spo2) ≥ 93% on room air at screening

inclusion criteria: - age ≥ 18 years - willing and able to provide written informed consent prior to performing study procedures - severe acute respiratory syndrome coronavirus (sars-cov)-2 infection confirmed by polymerase chain reaction (pcr) test ≤ 5 days before randomization or clinical presentation consistent with covid-19 infection (fever or cough or shortness of breath) with positive igm serology - currently hospitalized or in an emergency department - peripheral capillary oxygen saturation (spo2) ≥ 93% on room air at screening