Mesenchymal Stem Cell-Derived Exosomes Can Effectively Improve the Hair Count and Terminal Hair Diameter in Androgenetic Alopecia

Background and Objective: Androgenetic alopecia (AGA) is a common cause of male hair loss, and it is urgent to explore effective treatments. The purpose of this study was to evaluate the safety and preliminary efficacy of local injection of autologous or allogeneic stem cell exosomes in the treatment of AGA. Methods: Eight male subjects with AGA were treated with intradermal injection of stem cell exosomes. The treatment regimen was injected once every 4 weeks for 24 weeks. The changes in hair density (hairs/cm2) and hair diameter (mm) in the target area were evaluated at baseline (0 week), 12 weeks and 24 weeks by standardized hair mirror image analysis. Results: The 24-week treatment was well tolerated and no serious adverse events were reported. The analysis after treatment showed that the hair density and hair diameter of the patients were significantly improved compared with the baseline (p < 0.05). This improvement continued to increase during treatment. Conclusion: This preliminary study shows that intradermal injection of stem cell exosomes is a promising and safe strategy that can effectively promote hair growth and thickening in male AGA patients. This therapy provides a potential new treatment option for AGA, which is worthy of further large-scale research to verify its long-term effect and mechanism.