Safety of Allogeneic Adipose Tissue-Derived Mesenchymal Stem Cells for the Treatment of Complex Perianal Fistulas Not Associated With Crohn's Disease: A Phase I Clinical Trial.

Background: Anal fistula treatment aims to eradicate the fistula, preserve the sphincter, prevent recurrence, and allow an early return to daily activities for the patient. Because of the difficulty of achieving these goals, stem cell-based therapy has emerged for the treatment of complex perianal fistula with promising results.

Objective: The objective of this study was to evaluate the safety of allogeneic mesenchymal stem cells in the treatment of complex anal fistula in patients without Crohn's disease.