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24/10 Optimal management of perianal Crohn’s disease commissioning brief


Published: 22 March 2024

Version: V1.0

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The aim of the Health Technology Assessment (HTA) Programme is to ensure that high quality research information on the clinical effectiveness, cost-effectiveness and broader impact of healthcare treatments and tests are produced in the most efficient way for those who plan, provide or receive care from NHS and social care services. The commissioned workstream invites applications in response to calls for research on specific questions which have been identified and prioritised for their importance to the NHS, patients and social care.

Research question

What is the optimal management for fistulising perianal Crohn’s disease?

  1. Intervention: Tailored surgical repair. Most appropriate surgery with intention to repair, to include anatomical and non-anatomical repairs. Applicants to define and justify.
  2. Patient group: Patients with perianal fistula suitable for surgical repair (and established on optimal medical biologic therapy for at least 3 months).
    Applications are encouraged which include recruitment from geographic populations with high disease burden which have been historically underserved by research activity in this field.
  3. Setting: Secondary care.
  4. Comparator: Seton removal. Participants in the control arm may subsequently have surgical treatment if needed.
  5. Study design: A randomised controlled trial with an internal pilot phase to test key trial processes such as recruitment and adherence. Clear stop/go criteria should be provided to inform progression from pilot to full trial.
  6. Important outcomes: Clinical and radiological fistula healing; health-related quality of life (HRQoL).
    Other outcomes: Pain; incidence of infection/sepsis; ability to undertake activities of daily living; long term adverse effects or complications (e.g. continence impairment); CAF-QoL (pCD core outcome set); time to relapse or remission; reoperation rates; patient acceptability.
    Existing Core Outcomes should be included amongst the list of outcomes unless a good rationale is provided to do otherwise. Applicants are encouraged to report recruitment and findings disaggregated by sex (and other demographic factors where relevant).
  7. Minimum duration of follow-up: Applicants to define and justify follow-up (long-term follow-up is likely to be particularly key for surgical treatments).
    Longer-term follow up: If appropriate, researchers should consider obtaining consent to allow potential future follow-up through efficient means (such as routine data) as part of a separately funded study.


Crohn’s disease is a chronic inflammatory disorder that can affect any part of the gastrointestinal tract from the mouth to the anus, but most commonly causes inflammation and ulceration of the last part of the small intestine (ileum) and the large intestine (colon). It is estimated that Crohn’s disease affects about one in every 650 people in the UK.

Perianal Crohn’s disease (pCD) is a particularly severe and debilitating form of Crohn’s disease localised to the area surrounding the anus (back passage). Symptoms of pCD include pain, swelling around the perianal area, faecal incontinence and leakage of blood, pus or stool. Physical manifestations of pCD include perianal fistulas and associated abscesses. Perianal fistulas are abnormal tunnels or passageways that occur between the lower parts of the gut and the skin near the anus. They appear as tiny openings in the skin that can leak pus or sometimes faecal matter. Complex perianal fistulas have several abnormal passages and openings, or passages that go deep inside the body, and often have other complications such as abscesses. Due to these symptoms fistulising pCD is a debilitating illness that often leads to work disability, psychological, sexual and social problems and has a huge detrimental impact on the patient’s quality of life.

Perianal fistulas are managed with both medical and surgical approaches. Medical therapies include antibiotics, immunosuppressants and biological therapy. The main aim of surgical intervention is to manage perianal sepsis and drain any abscesses usually through the use of setons, a silicon, string like material that promotes healing of the fistula by keeping it open.

Setons are not usually curative and remission rates can be low, so patients often go on to have surgical repair. There are a number of different surgical options for attempting to repair perianal fistulas including but not limited to fistulectomy, advancement flap, ligation of the intersphincteric fistula tract (LIFT) procedure, fibrin glue and plugs, and laser closures including video assisted anal fistula treatment (VAAFT). There is a lack of high-quality evidence comparing different surgical interventions to palliation/drainage management alone and despite the number of patients requiring surgical intervention for perianal fistulas, and the high burden on quality of life there is a lack of consensus for the best management of these patients.

This topic has been highlighted as a research priority by both the Clinical Research Network (CRN) Gastroenterology speciality group and a James Lind Alliance priority setting partnership for inflammatory bowel disease. The HTA Programme therefore wishes to commission the trial outlined above.

Additional commissioning brief background information

A background document is available that provides further information to support applicants for this call. It is intended to summarise what prompted the call and the existing evidence base, including relevant work from the HTA and wider NIHR research portfolio. It was researched and written on the basis of information from a search of relevant sources and databases, and in consultation with a number of experts in the field. If you would like a copy please email

Making an application

The HTA Programme recognises that there may be challenges in responding to this commissioning brief. If applicants would like to discuss their application with a member of the secretariat, please contact us by email

If you would like to apply for this funding opportunity, you can begin your application via the Funding opportunities page.

Your application must be submitted online no later than 1pm, 24 July 2024. Applications will be considered by the HTA Funding Committee at its meeting in September 2024.

Guidance notes and supporting information for HTA Programme applications are available by clicking the links.

Shortlisted Stage 1 applicants will be given 8 weeks to submit a Stage 2 application. The Stage 2 application will be considered at the Funding Committee in January 2025.

Applications received electronically after 1pm on the due date will not be considered.

For commissioned topics, the Programme strongly discourages the practice of the same co-applicant joining more than one competing team. There may be unusual circumstances where the same person could be included on more than on application eg. a lead from a named charity or a unique national expert in a condition.

For such exceptions, each application needs to state the case as to why the same person is included. The shared co-applicant should not divulge application details between teams, and both teams should acknowledge in their application that they are aware of the situation, and that study details have not been shared.

Should you have any queries please contact us via email: