he primary objectives are:

Phase 1/2 (Cohort 1)

To exclude futility of REGN10933+REGN10987 compared to placebo, as measured by death or mechanical ventilation

To evaluate the safety and tolerability of REGN10933+REGN10987 compared to placebo Phase 2 (Cohort 1A)

To evaluate the clinical efficacy of REGN10933+REGN10987 compared to placebo, as measured by death or mechanical ventilation

To evaluate the safety and tolerability of REGN10933+REGN10987 compared to placebo Phase 3 (Cohort 1 and Cohort 1A)

To evaluate the clinical efficacy of REGN10933+REGN10987 compared to placebo, as measured by death or mechanical ventilation