Collagen Paste vs Mucosal Advancement Flap for FIA

Collagen Paste Injection Compared With Mucosal Advancement Flap for the Treatment of Fistula-in-ano: Single Centre Non-inferiority Randomised Controlled Trial

The treatment for fistula-in-ano (FIA) remains a challenge to General and Colorectal Surgeons Worldwide. A variety of surgical treatments have been described for high anal fistulas, but none offers the panacea of fistula eradication with guaranteed preservation of continence. This study compares Collagen paste injection to mucosal advancement flap for the treatment of fistula-in-ano.

Study Overview

• Status: Recruiting
• Conditions: Fistula-in-ano
• Intervention / Treatment: Procedure: Collagen Paste; Procedure: Mucosal advancement

Detailed Description

Rectal advancement flaps have been advocated as a means of closing high fistulas with preservation of the external sphincter muscle. With this technique, it shows promising results with success rate of approximately 60%. However, complications have been reported, in particular with a change of continence in 30-35% of patients.

Collagen paste is a novel sphincter-preserving method for fistula closure. Permacol (Medtronic, USA) is a sterile acellular cross-linked porcine dermal collagen matrix suspension. The paste-like suspension form a matrix that accelerates neovascularization, cellular infiltration which promotes healing and fistula closure. The theoretical benefits of paste form compared to previous collagen plug design is that the collagen can moulded into the fistula cavity or tract. This allows better tissue contact with the collagen thus improves healing and reduces the chance of dislodgement. Limited data is available to date. Success rates of collagen paste range from 47.6% to 63%. Hence it has a potential to be the first-line treatment for high FIA with low complication rates and without causing disruption to the anal sphincter complex.

• Study Type: Interventional
• Enrollment (Estimated): 118
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Kaori Futaba, FRCS; Phone Number: 35051495; Email: kfutaba@surgery.cuhk.edu.hk

Study Locations

• Hong Kong
  • Sha Tin, Hong Kong
    • Recruiting
    • Prince of Wlaes Hospital
    • Contact: Kaori Futaba; Phone Number: 35051495; Email: kfutaba@surgery.cuhk.edu.hk
  • New Territories
    • Shatin, New Territories, Hong Kong
      • Recruiting
      • Department of Surgery, Chinese University of Hong Kong
      • Contact: Kaori Futaba; Email: kfutaba@surgery.cuhk.edu.hk

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Clinical diagnosis of high cryptoglandular fistula-in-ano.
• Patients must have undergone a prior EUA to characterise the nature of the fistula.
• The fistula tract should be ≥ 2 cm in length.
• Only a single internal fistula opening should be present at EUA, such that the fistula is suitable for treatment by insertion of a seton drain.
• Patients must have been treated with a draining seton for a minimum period of 6 weeks prior to randomisation.
• Patients must be aged ≥ 18 years and able to provide informed consent.
• Fistulas must be of cryptoglandular aetiology.

Exclusion Criteria:

• Unable/unwilling to provide informed consent.
• Contraindication to general anaesthesia or spinal anaesthesia.
• Low trans-sphincteric fistulas.
• Non-cryptoglandular fistulas (e.g. Crohn's disease, obstetric, irradiation, malignant, etc.).
• Other perineal fistulas (e.g. rectovaginal fistulas, pouch-vaginal fistulas, etc.).
• Complex disease in which more than one internal fistula opening is present and requiring concurrent insertion of more than one fistula plug.
• Clinical evidence of active perianal sepsis. In the event that there is disagreement between clinical and radiological assessment of active sepsis/collection, the clinical opinion will prevail.
• Cultural or religious objection to the use of pig tissue.
• Absolute contraindication to magnetic resonance imaging (MRI) (e.g. cardiac pacemaker).
• Patients with recurrent anal fistulas previously treated with a fistula plug.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Collagen Paste; Seton is removed, the fistula tract is de-epithelialised and collagen paste applied.	Procedure: Collagen Paste; Collagen paste injection
Active Comparator: Mucosal Advancement Flap; The internal opening is excised and is covered with a "U-shape" rectal mucosal flap	Procedure: Mucosal advancement; Mucosal advancement flap

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Clinical healing of Fistula-in-ano	Clinical healing of the fistula-in-ano	1 year

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
30-day morbidity	30-day morbidity using Clavien-Dindo classification	30 days
Quality of life score	Assess effect on Quality of life post operatively using Short Form 36 Health Survey	1 year
Postoperative pain score	assessment of postoperative pain using visual analog score from 0 (no pain) to 10 (severe pain)	1 week
Faecal incontinence rate	Assess postoperative effect on continence	1 year
Hospital readmission rate	Assess hospital re-admission rate	1 year

Collaborators and Investigators

• Sponsor: Chinese University of Hong Kong

Study record dates

Study Major Dates

• Study Start (Actual): January 26, 2024
• Primary Completion (Estimated): March 31, 2026
• Study Completion (Estimated): March 31, 2027

Study Registration Dates

• First Submitted: April 22, 2024
• First Submitted That Met QC Criteria: April 24, 2024
• First Posted (Actual): April 26, 2024

Study Record Updates

• Last Update Posted (Actual): April 26, 2024
• Last Update Submitted That Met QC Criteria: April 24, 2024
• Last Verified: April 1, 2024

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Pathological Conditions, Anatomical; Fistula
• Other Study ID Numbers: CREC2021.724-T

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No