The MEseNchymal coviD-19 Trial: MSCs in Adults With Respiratory Failure Due to COVID-19 or Another Underlying Cause

Inclusion Criteria: * Male or female, 18 years of age or older * Respiratory failure with the following signs and symptoms: 1. P/F ratio \<300 mmHg 2. Onset within one week of a known insult or new or worsening respiratory symptoms. 3. Chest imaging shows bilateral opacities, which are not fully explained by effusions, lobar/lung collapse, or nodules. * Respiratory failure which is not fully explained by cardiac failure or fluid overload. * Onset of respiratory failure within the past 48 hours (as defined in inclusion criterion 2 Exclusion Criteria: * \<18 years of age * Patient is known to be pregnant * Known active malignancy that required treatment in the last year * WHO Class III or IV pulmonary hypertension * Venous thromboembolism currently receiving anti-coagulation or within the past 3 months * Currently receiving extracorporeal life support * Severe chronic liver disease (Child-Pugh score \>12) * "Do Not Attempt Resuscitation" order in place * Treatment withdrawal imminent within 24 hours * BMI \> 45 kg/m2. * Received any investigational research agent within 60 days or within five half-lives of the last treatment (if the half-life of the investigational agent is known to be longer than 12 days) prior to the planned administration of study treatment. * Known positive test for human immunodeficiency virus 1 (HIV 1), HIV 2, hepatitis B virus, Hepatitis C virus or any other infection which the opinion of the Investigator is likely to impact on the ability of the patient to participate in the study. * Known sensitivity to dimethylsulfoxide (DMSO) or any other component of the study treatment.