The purpose of this open, multicenter pilot trial is to evaluate the tolerance of the combination of a gel and a plug made of Wharton's jelly in the treatment of ano-perineal fistulas resistant to surgical treatment.

Inclusion Criteria:

• Male or female, aged 18 to 65 years.
• Patient with a single anal fistula resistant after at least one surgical treatment. Fistula may be related to Crohn's disease.
• Patient with an upper transsphincteric or lower transsphincteric fistula.
• Patient presenting fistula with or without intersphincteric diverticula.
• Fistula effectively drained with a seton.
• Informed and consenting patient.
• Patient who is a member or a beneficiary of a national health insurance plan.

Exclusion Criteria:

• Pregnant or breastfeeding woman or woman of childbearing age without effective contraception.
• Patients who have had more than one failed obstruction technique.
• Patient with more than one internal orifice.
• Patient with an MRI proven abscess.
• Patient with an uncontrolled infection.
• Patient with a contraindication to anesthesia.
• Person deprived of liberty by a judicial or administrative decision.
• Adult subjected to a legal protection measure or unable to express his / her consent.