Nebulization of Mesenchymal Stem Cells Secretome Attenuates Acute Respiratory Distress Syndrome Caused by SARS-CoV-2 Corona Virus: An Open-Label, Controlled Trial.

Background: Previous investigations have indicated the potential of mesenchymal stem cell (MSC) transplantation in treating COVID-19. However, the limited lifespan of transplanted cells constrains this therapeutic approach. the immunomodulatory, anti-inflammatory, and regenerative properties of MSCs secretome could be a promising solution to improve patient outcomes.

Materials and methods: A randomized clinical trial was conducted in Kerman, a region in south-central Iran. This study enrolled twenty patients in the severe phase of COVID-19 pneumonia, randomly allocated into either investigation or control groups. Both groups received standard therapy, the investigation group additionally received nebulized concentrated MSCs secretome, 2 mL administered twice daily for five consecutive days. To evaluate the effect of MSCs secretome therapy, the length of stay in the intensive care unit (ICU), oximetry, and paraclinical results were assessed at baseline and 5 days after ICU admission.

Results: Baseline characteristics were balanced and distributed among the two groups. No adverse effect was observed in MSCs secretome-treated patients. Compared to the control group, the investigated group exhibited a decrease in ICU stay duration (10.90 ± 3.75 vs. 5.50 ± 1.64 days, P = 0.04) and a significant improvement in O2 saturation (60.65 ± 16.58 vs. 79.47 ± 15.36, P = 0.02). In addition, significant decreases in CRP, PTT, and INR and upregulation in lymphocyte fraction were observed in the investigation group during the study period.

Conclusions: The findings of this study underscore the prospective advantages and safety of the secretome of MSCs as a viable therapeutic choice in COVID-19 patients. We advise verifying our results through additional clinical trials at various disease stages.