Study of Mesenchymal Stem Cells for the Treatment of Ileal Pouch Fistula's in Participants With Crohn's Disease (IPAAF)

Inclusion Criteria

1. Men and women 18-75 years of age who have undergone an ileal pouch anal anastomosis at least 6 months prior who have developed a clinical diagnosis of Crohn's disease of the pouch as determined by a combination of clinical symptoms, pouchoscopy with biopsy, enterography.

2. Single and multi-tract (up to 2 internal and 3 external openings) fistula tract arising from the ileal pouch, ileal anal anastomosis, or anal canal distal to anastomosis that travels to the perianal skin, perineal body, or vagina. Patients with fistulas that arise from the pouch, anastomosis, or anal canal distal to the anastomosis will both be included in enrollment.

   1. Acceptable internal openings and tract locations for the fistula to arise from include the ileal pouch body, the pouch anal anastomosis, and the anal canal distal to the anastomosis.
   2. Acceptable external openings and tract locations for the fistula to arise from include the perianal skin, perineal body, and/or the vaginal wall.
3. Concurrent Crohn's related therapies with stable doses (>2 months) corticosteroids, 5-ASA drugs, immunomodulators, anti-TNF therapy, anti-integrin and anti-interleukin are permitted.
4. Have failed conventional medical therapies described above, defined as a lack of response to systemic immune suppression (e.g. azathioprine, methotrexate, 6-mercaptopurine) or biologic (e.g. anti-TNF, anti-integrin, anti-interleukin) therapies to treat fistulizing CD for at least 2 months
5. Have no contraindications to MR evaluations: e.g. pacemaker or magnetically active metal fragments, claustrophobia
6. Competent and able to provide written informed consent
7. Ability to comply with protocol.

Exclusion Criteria

1. Inability to give informed consent.
2. Severe antibiotic refractory pouchitis
3. Severe cuffitis refractory to antibiotics
4. Change in medical management for CD in the previous 2 months or changes anticipated in the next 2 months
5. Clinically significant medical conditions within the six months before administration of MSCs: e.g. myocardial infarction, active angina, congestive heart failure or other conditions that would, in the opinion of the investigators, compromise the safety of the subject.

6. Specific exclusions;

   1. HIV
   2. Hepatitis B or C
   3. Abnormal CBC at screening

   i. Platelets <50 kg/uL or greater than 1.5 million kg/uL ii. WBC <50 x kg/uL iii. Hbg <7.0 g/dL d. Abnormal AST or ALT at screening(defined as >/= 2x ULN)

7. History of cancer including melanoma (with the exception of localized skin cancers) within one year of screening
8. History of colorectal cancer within 5 years
9. Investigational drug within thirty (30) days of baseline
10. Pregnant or breast feeding or trying to become pregnant

11. Branching fistula tract that has > 2 internal openings or 3 external openings,

    1. Subjects with greater than 3 blind/branching tracts are excluded
    2. Fistula tracts on the left and/or right side are allowed
12. Allergic to local anesthetics
13. Unwilling to agree to use acceptable contraception methods during participation in study
14. Subjects with a non-abscessed chronic cavity will not be included in enrollment