More detailed information as to inclusion and exclusion criteria, timing of MSC administration relative to onset of disease, comorbidities, clinical course of each patient, and evaluation of inflammatory mediators and cell populations for both treated and placebo patients are needed to better determine potential MSC efficacy and mechanisms of action. Importantly, there is no discussion as to whether the approach be further investigated in only critically severe and/or severe patients or for the broader range of clinical presentations of COVID-19 respiratory infection.