Muscle mass gain and strength recovery after discharge of critical COVID-19 patients treated with mesenchymal stromal cell infusion: a randomized clinical trial.

INTRODUCTION

during the COVID-19 pandemic, patients with severe infection suffered from profound muscle loss and physical dysfunction. The immunomodulatory and anti-inflammatory properties of mesenchymal stromal cells (MSCs) could represent a new therapeutic strategy, reducing post-COVID-19 sequelae. This study aimed to evaluate the influence of MSC infusion on body composition, functionality, and the occurrence and severity of sarcopenia in critically ill COVID-19 patients after hospital discharge, correlating with clinical outcomes, viral load, and pro-inflammatory cytokines.

METHODS

a prospective, randomized, double-blind, placebo-controlled, phase I/II, single-center study with 16 ICU patients (MSC = 10; placebo = 6) who received three intravenous doses of 5 × 10⁵ MSCs/kg. After discharge (at two and four months), patients underwent anthropometric assessment, body composition by bioelectrical impedance analysis, and functional tests [handgrip strength (HGS), gait speed (GS), and "Timed Up and Go" (TUG)] to diagnose sarcopenia. Cytokines, viral load, CRP, ferritin, and chest CT scans were also evaluated.

RESULTS

nine patients completed follow-up (MSC = 5; placebo = 4). Appendicular skeletal muscle mass (p = 0.004), appendicular skeletal muscle index (p = 0.004), phase angle (p = 0.014), left arm circumference (p = 0.033) and HGS (p = 0.009) showed better results for the MSCs group compared to the placebo group between two and four months. TUG improved in both groups (p = 0.039). There was no difference in the diagnosis of sarcopenia between the groups. Myosteatosis was present in most patients.

CONCLUSION

MSCs infusion positively impacted the recovery of muscle mass and strength after severe COVID-19.