Primary Outcomes
Measure: number of subjects with treatment emergent adverse events and serious adverse events Time: absolute number through the end of the study, approximately 56 days
Measure: number of subjects with change in laboratory parameters Time: absolute number and change from baseline through the end of the study, approximately 56 days
Measure: exposure of galidesivir as measured by plasma concentrations Time: 24 hours post dose on Day 1 through 12 hours post dose on Day 7
Secondary Outcomes
Measure: yellow fever virus (YFV) titer (Group A) Time: change in YFV titer from baseline through Day 21
Measure: antiviral effect on SARS-CoV-2 in the respiratory tract - COVID-19 (Group B) Time: change in SARS-CoV-2 from baseline through Day 21
Measure: changes in clinical status using 8-point ordinal scale in COVID-19 (Group B) Time: through Day 21
Measure: changes from baseline and time to improvement using NEWS in COVID-19 (Group B) Time: through Day21
Measure: mortality Time: mortality at Day 56