Late Breaking Abstract - Mesenchymal stromal cells as a salvage treatment for persistent ARDS

Aims: Mesenchymal stromal cells (MSCs) are promising but with limited safety and efficacy profiles in ARDS. To explore the safety and salvage role of Umbilical Cord derived MSCs (UCMSCs) in persistent ARDS (pARDS) patients, we collected the preliminary data from a single arm prospective study (NCT03608592) in four ICUs of a teaching hospital. Methods: Moderate to severe ARDS with unimproved oxygenation following 24 hours’ conventional therapies were defined as pARDS. A single dose (1 million/kg) of UCMSCs was infused intravenously. Infusion associated events (IAEs) and clinical outcomes were observed and compared with propensity score matched (PSM) controls. Results: Twenty-two pARDS with UCMSCs infusion with 1:1 PSM controls were finally analyzed. No prespecified IAEs was observed. Compared with PSM controls, UCMSCs significantly improved P/F, decreased lung injury (Fig1) and reduced adjusted mortality at 60 days (45% vs 55%, HR 0.25, 95% CI 0.08-0.73, P=0.01) and ventilator free days (mean difference 7.5, 95% CI 3-12, P Conclusion: The present data showed the safety and potential survival benefit of a single dose of UCMSCs in persistent ARDS. Larger trials are warranted.