Re-treatment From a Phase I Study of MSC-AFP in Patients With Perianal Fistulas

This study is an extension to re-treat partial and non-responders from the previously
approved Phase 1 MCS-AFP protocols IRB #12-009716 (Crohn's Disease perianal fistulas) and
15-003200 (cryptoglandular perianal fistulas). This study will enroll patients that have
persistent symptomatic perianal disease despite being treated with an MSC coated fistula
plug, and also treat patients that have had recurrence of their perianal fistula.

As per the previously approval treatment under IND 15356, patients will have a single
affected fistula treated, which is the same fistula that was treated in the original
protocol. The matrix for delivering the cells is a Gore Bio-A Fistula Plug.

Subjects will be screened at outpatient clinic visits and interested qualified subjects will
be offered participation in the trial and consented. At the first study visit (Visit 1;
Screening visit), the patient will be evaluated and assessment will be made if an EUA is
clinically necessary to assess the fistula. As this is a re-treatment trial, patients with
incomplete response to initial plug placement typically have close follow up, recent MRI
imaging, and may have a seton in place. If an EUA is clinically indicated, this would be by a
colorectal surgeon for drainage of sepsis and placement of a seton as part of the standard
clinical care for perianal fistula.

Patients will return on: Day 1, Week 4, Week 12, and Week 24.

Inclusion Criteria

1. Males and females 18-65 years of age.

2. Residents of the United States.

3. Single draining perianal fistula for at least three months despite standard therapy

4. Concurrent therapies are permitted (such as antibiotics, corticosteroids,
thiopurines).

5. Have no contraindications to MR evaluations: e.g. pacemaker or magnetically active
metal fragments, claustrophobia

6. Ability to comply with protocol

7. Competent and able to provide written informed consent

8. Patients that were treated with an MSC-coated fistula plug in the study IRB#12-009716
or IRB#15-003200

Exclusion Criteria

1. Inability to give informed consent.

2. 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 patient.

3. Specific exclusions: Evidence of hepatitis B, C, or HIV

4. History of cancer including melanoma (with the exception of localized skin cancers)

5. Investigational drug within thirty (30) days of baseline

6. A resident outside the United States

7. Previous allergic reaction to a perianal fistula plug.

8. Allergic to local anesthetics

9. Pregnant patients or trying to become pregnant or breast feeding.

10. Non-enterocutaneous tracts (i.e. recto-vaginal, entero-vesicular)