Mesenchymal Stromal Cells for COVID-19 and Viral Pneumonias

Study Design: This open-label phase 1 trial in 10 patients will assess the efficacy and safety of UC-MSCs given on day 1 and 3 in hospitalized patients with acute respiratory symptoms between 1 and 7 days after the onset of symptoms. The following will be assessed in all subjects: * Age, sex, comorbidities, date of symptoms, source of infection, type of admission, APACHE II score, SOFA score, Clinical status, vital signs including temperature, respiratory rate, oxygen saturation, oxygen requirement, CBC with neutrophil counts, lymphocyte count, CRP, chest imaging (CT or X-ray), location and status in hospital. * Safety and efficacy: Day 0 (baseline), 3, and 5. Monitoring at 14, 21 and 28 days and monthly for 3 months will be obtained by telephone consult and chart review with serial laboratory. * Serum or plasma antibody titer to SARS-CoV-2: Day 0, and 5 (additional days 14, 21 and 28 may be included, as available). * SARS-CoV-2 PCR from nasopharyngeal swabs: Day 0 and 5. (additional day 14, 28 and 60 day samples may be tested if available or at any time when there is clinical suspicion for COVID-19 persistence). * Outcome measures: O2 requirement (PaO2/FiO2 ratio or SpO2/FIo2), supplemental oxygen strategy (nasal cannula, high flow nasal cannula, noninvasive ventilation, intubation and invasive mechanical ventilation, neuromuscular blocking agent use, prone positioning, corticosteroids, ECMO), vasopressors, renal support, ICU LOS, ICU mortality, Hospital LOS, Hospital mortality, 28 day mortality. Study Agent: • Allogeneic UC-MSCs given intravenously at 1.2-1.5 x 106 cells/kg on day 1 and day 3 of study entry. A maximum dose of 100 x 106 cells would be given in each dose. All cellular product will be given with actively growing cells \>24 hours from the time of thawing in the Center for Cellular Therapy (CCT) at MUSC. Any emerging FDA guidance will be followed. Primary Safety Objective: Evaluate the safety of treatment with UC-MSCs in hospitalized patients with COVID-19 and respiratory symptoms. Primary Safety Endpoint: 1\. Rapid deterioration of respiratory or clinical status within 6 hours after transfusion of UC-MSCs Secondary Safety Endpoints: 1. Cumulative incidence of serious adverse events during the study period 2. Transfer to intensive care unit (ICU) 3. Type and duration of respiratory support (and other ICU support) 4. ICU mortality and length of stay 5. Hospital mortality and length of stay 6. Ventilator-free days 7. 28 day mortality Exploratory Efficacy Objective: Evaluate changes in oxygenation, progression, and regression of viral pneumonias Efficacy Endpoint: Change from baseline in PaO2/FiO2 ratio at day 5 Biologic Samples will be serially collected to determine mechanisms of effect. Propensity matching of the cohort to the MUSC COVID-19 Biorepository population will provide a population for comparison.