Multiple Dosing of Mesenchymal Stromal Cells in Patients With ARDS (COVID-19)

Inclusion Criteria: * Age 18-80 years * Meets 'Berlin Criteria' for diagnosis of moderate to severe ARDS for a minimum of 4 hours * Less than 48 hours on a ventilator after meeting criteria for diagnosis of ARDS * SARS-CoV-2 (proven by RT-PCR assay) with radiographic infiltrates * PaO2/FiO2 \< 250 * Positive end-expiratory airway pressure (PEEP) \>5 cm H20 * Elevated C-reactive protein (above laboratory upper limit of normal) * Meets organ function requirements, including left ventricular ejection fraction (LVEF) \>35% ( as defined below) * Off other investigational agents directed against inflammatory cytokines 48 hours prior to enrollment; agents directed against the replication of SARS-CoV-2 \[e.g., Remdesivir\] are permitted * Voluntary informed consent in person or virtually by the patient or patient surrogate considering the face to face limitations during the COVID-19 pandemic and, given the nature of the study population, which frequently requires mechanical ventilation with sedation, surrogate consent will likely occur in a substantial proportion of the study population (this will remain a valid consent until the patient is fully alert, and aware, and can provide a second consent to continue participation in the study). * Adequate organ function is defined as: * Renal: Calculated estimated glomerular filtration rate \>30 mL/min/1.73 m2 (on chemistry panel) * Hepatic: Bilirubin \<3x upper limit of normal (ULN) and AST, ALT and alkaline phosphatase \<5x ULN * C…