P718 A Phase I Study of Ex Vivo Expanded Allogeneic Bone Marrow Derived Mesenchymal Stem Cells for the Treatment of Pediatric Perianal Fistulizing Crohn’s Disease

Otero Piñeiro, A.(1)*; Lightner , A.L.(1);Reese , J.(2);Ream , J.(3);Nachand , D.(4);Adams , A.(5);VanDenBossche, A.(1);Kurowski, J.(6);

(1)Digestive Disease Surgical Institute- Cleveland Clinic, Colorectal Surgery, Cleveland, United States;(2)Cleveland Clinic, National Center for Regenerative Medicine, Cleveland, United States;(3)Digestive Disease Surgical Institute- Cleveland Clinic, Department of Abdominal Radiology-, Cleveland, United States;(4)Digestive Disease Surgical Institute- Cleveland Clinic, Department of Abdominal Radiology, Cleveland, United States;(5)Digestive Disease Surgical Institute- Cleveland Clinic, Department of Colorectal Surgery, Cleveland, United States;(6)Pediatric Institute- Cleveland Clinic, Pediatrics, Cleveland, United States;

Background

Background: Mesenchymal stem cells have been used for the treatment of perianal Crohn’s fistulizing disease by direction injection. However, no studies to date have included pediatric patients.
Objective: To determine safety and efficacy of mesenchymal stem cells for pediatric perianal fistulizing Crohn’s disease.



Methods

Design: Phase I safety trial
Settings: Tertiary inflammatory bowel disease referral center
Patients: Crohn’s patients aged 13-17 with perianal fistulizing disease. 
Intervention: 75 million mesenchymal stem cells were administered with a 22G needle by direct injection after curettage and primary closure of the fistula tract. A repeat injection of 75 million mesenchymal stem cells at 3 months was given if complete clinical and radiographic healing were not achieved.
Main outcomes measures: Adverse and serious adverse events at post procedure day 1, week 2, week 6, month 3, month 6 and month 12. Clinical healing, radiographic healing per magnetic resonance imaging, and patient reported outcomes at the same time points.

Results

Results: A total of 7 pediatric patients were enrolled and treated (6 male; median age of 16.7 years). There were no adverse or serious adverse events reported related to investigational product. At six months, 83% had complete clinical and radiographic healing. The perianal Crohn’s disease activity index, Wexner incontinence score, and VanAssche score had all decreased at six months.
Limitations: Single institution and open label.

Conclusion

Bone marrow derived mesenchymal stem cells offer a safe, and likely effective, alternative treatment approach for pediatric perianal fistulizing Crohn’s disease.