AIM: Many perianal fistulae in Crohn's disease do not respond to conventional surgical and medical management and recurrence rates are high. The study evaluated the safety and feasibility of allogeneic adipose-derived stem cells for the treatment of perianal fistula in Crohn's disease.
METHOD: A multicentre, open-label, dose escalation pilot study was performed. The first three patients (group 1) were administered 1 × 10(7) cells/ml based on the size of the fistula tract. Four weeks later, after which time this dose had been confirmed to be safe, the next three patients (group 2) were administered 3 × 10(7) cells/ml. The end-point was complete closure at 8 weeks after the injection. Patients who attended for the 8 week assessment were followed for an additional 6 months.
RESULTS: There were no adverse events of Grade 3 or 4 severity and no adverse events related to the treatment with allogeneic adipose-derived stem cells. Two patients in group 1 achieved complete closure of the fistula at month 4 and month 6, and one patient in group 2 achieved complete closure at 8 weeks. The closure was sustained up to month 8 in all three of those patients.
CONCLUSION: These data suggest that allogeneic adipose-derived stem cells may be a feasible treatment option for perianal fistula in Crohn's disease.