Seeded Cells on Matrix Plug Treating Crohn's Perianal Fistulas (STOMP-II)

Inclusion Criteria:

1. Provision of signed and dated ICF.

2. Ability and willingness to comply with study protocol and study requirements for theduration of the study.

3. Male or female, 18-70 years of age

4. Subjects with CD diagnosed at least 6 months prior to screening visit.

5. Subjects with a single fistula tract with one internal opening and one externalopening.

6. Subjects whose perianal fistula(s) were previously treated with either biologic orconventional therapy whose fistula has demonstrated a failed response or who havedocumented medication intolerance.

7. Women of childbearing potential (WCBP) must have negative serum pregnancy test atscreening (sensitive to 25 IU human chorionic gonadotropin). WCBP participating inthis study must agree to use an adequate method of contraception during the entireduration of the study. Males who have sexual partners that are women of childbearingpotential must be willing to use a barrier method for contraception for the durationof study.

Exclusion Criteria:

1. Clinically significant medical conditions within the six months before screeningthat would, in the opinion of the investigator, compromise the safety of the subjectwith study participation and/or the ability of the subject to follow study protocol.

2. Evidence of hepatitis B, C, or HIV or subjects with congenital or acquiredimmunodeficiencies.

3. Participation in an investigational drug study (within 30 days of lastadministration from screening visit) or investigational medical device study (within 1 year of implant from screening visit) where investigational treatment (drug ordevice) is placed in rectum, vagina, or near fistula location, or that maypotentially interact with study treatment.

4. History (within previous 5 years of screening visit) of invasive cancer includingmelanoma (with the exception of localized skin cancers).

5. Subjects pregnant, trying to become pregnant, or are breast feeding.

6. Subjects with known allergies or hypersensitivity to aminoglycosides andcontraindications to Magnetic Resonance (MR) evaluations and/or to MR contrast.

7. History of clinically significant fat-directed autoimmunity.

8. Genito-urinary fistulization, including rectovaginal (i.e., fistulae that transversethe vaginal canal).

9. Presence of an ileal anal pouch.

10. Active, unresolved infection requiring parenteral antibiotics.

11. Any major surgery of the gastrointestinal tract (including one or more segments ofthe colon or terminal ileum) within 3 months prior to screening visit. Presence ofstoma is not exclusionary.

12. Subjects who had a definitive surgical procedure for the target fistula or aperianal procedure that resulted in a large soft tissue defect within 6 months priorto screening visit.

13. Subjects where the target adipose collection harvest site is compromised due to aprevious cool sculpting procedure, local radiation, chemotherapy, recent tattoos,local infection, or other reasons that may compromise the adipose tissue for studyuse.

14. Subjects previously treated with Cx601/Alofisel or other allogeneic or autologousstem-cell therapy within the past 6 months.

15. Contraindications to the anesthetic procedure (local and general) or to the adiposetissue collection procedure.

16. Subjects with one or more of the following fistula types or anatomic presentations:

17. Horseshoe fistulas

18. Fistulas that do not have an opening inside the anal canal or low rectum

19. Blind ending sinus tracts (no external opening)

20. Branching fistulas. A previously performed conversion of a branching fistulatract to a single tract is not exclusionary

21. >1 internal opening

22. Moderate or severe proctitis

23. Severe rectal mucosal fibrosis surrounding the internal opening preventing thesecuring of the fistula plug cap.

24. Any anatomical limitation to successfully securing the fistula plug cap

25. Evidence by colonoscopy of moderately or greater active luminal CD.

26. Subject with ongoing systemic or rectal steroids for CD in the last 2 weeks prior toscreening and baseline study visits.

27. History of, or concurrent high-grade dysplasia, adenocarcinoma, and carcinoma insitu on colonoscopy within 5 years of screening visit.

28. Subjects with renal insufficiency (creatinine value > 1.8 mg/dL, eGFR < 44, orpatient undergoing dialysis).

29. Subjects with a hemoglobin less than 8 gm/dL.

30. Subjects with serum aspartate transaminase (AST) or alanine transaminase (ALT) > 2times the upper limit of normal (ULN).

31. Subjects with an abscess within the fistula tract that cannot be resolved prior totreatment.

32. Subjects with known coagulopathy (abnormal INR) or thrombocytopenia as indicated bya platelet count < 75,000.

33. Subjects with history of substance abuse (drug or alcohol) that would interfere withthe ability to comply with the study protocol and study requirements.