Phase III DAS181 Lower Tract PIV Infection in Immunocompromised Subjects (Substudy: DAS181 for COVID-19): RCT Study

Eligible subjects (i.e., those meeting the Inclusion / Exclusion criteria) will be enrolled in one of four cohorts based on the following criteria: Cohort 1: All eligible subjects in the PoI who are ≥18 year old subjects with a PIV infection and meet all of the following criteria: 1.1 Meet criteria for being severely immunocompromised 1.2 Prior to the onset of PIV infection, had no ongoing need for oxygen therapy due to a chronic respiratory condition (e.g., COPD, sleep apnea) and are assessed as acutely hypoxemic due to their PIV infection 1.3 At the time of randomization are not on mechanical, bi-level or continuous positive airway pressure (Bi-PAP or CPAP) ventilation 1.4 Have no known concurrent respiratory viral coinfection(s) Cohort 2: All eligible subjects in the PoI who are ≥18 year old with a PIV infection (including those with PIV and another SAD-RV) who do not meet one or more of the listed criteria for Cohort 1. Cohort 3: All eligible subjects in the PoI who are \<18 year old subjects with a PIV infection (including those with PIV and another concurrent SAD-RV). There is no lower age limit for this cohort. Cohort 4: All eligible subjects in the PoI with a respiratory infection due to any SAD-RV infection except PIV. Eligible subjects with both PIV and an additional concurrent SAD-RV, will be enrolled for either Cohorts 2 or 3 depending on their age. There is no lower age limit for this cohort. Sub-Study: Patients with Severe COVID-19