Part A: Proportions (active vs. placebo) of subjects with progressive respiratory insufficiency.;Part B: Change from baseline in amount of SARS-CoV-2 virus RNA;Parts A and B: Proportions (active vs. placebo) of subjects experiencing treatment-emergent adverse events

Part A: Proportions (active vs. placebo) of subjects with progressive respiratory insufficiency.;Part B: Change from baseline in amount of SARS-CoV-2 virus RNA;Parts A and B: Proportions (active vs. placebo) of subjects experiencing treatment-emergent adverse events

Proportions (active vs. placebo) of subjects experiencing treatment-emergent adverse events;Proportions (active vs. placebo) of subjects with progressive respiratory insufficiency.

Proportions (active vs. placebo) of subjects experiencing treatment-emergent adverse events;Proportions (active vs. placebo) of subjects with progressive respiratory insufficiency.