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20/80 Endoscopic treatments for obesity




The aim of the HTA Programme is to ensure that high quality research information on the effectiveness, costs and broader impact of health technology is produced in the most efficient way for those who use, manage, provide care in or develop policy for the NHS. Topics for research are identified and prioritised to meet the needs of the NHS. Health technology assessment forms a substantial portfolio of work within the National Institute for Health Research and each year about fifty new studies are commissioned to help answer questions of direct importance to the NHS. The studies include both primary research and evidence synthesis.

Research question

What is the current state of the evidence for endoscopic treatments for obesity, and are they cost-effective? 

  1. Intervention: Endoscopic treatments for obesity.
  2. Patient group: People of any age with obesity and obesity-related comorbidities. 
  3. Control/Comparator: Any suitable control/comparator, including comparison of interventions against each other, using indirect comparisons if appropriate.
  4. Study design: An evidence synthesis by systematic review and a cost-effectiveness analysis. The scope of the evidence synthesis should be broad and include any currently available endoscopic obesity treatments (including those not currently in use in the UK). Randomised, non-randomised, and observational studies should be included in the review. 
  5. Outcomes and outputs: Weight; changes in diabetes status and/or cardiovascular risk; adverse events; re-intervention/revisional surgery; morbidity; mortality; quality of life; cost-effectiveness. Subgroup analyses should be undertaken if possible (e.g. people with/without diabetes, age groups etc.). The review should include an evidence map and identify unmet research needs.
    Where established Core Outcomes exist, they should be included amongst the list of outcomes unless there is good reason to do otherwise. 


In the UK, as in most other developed countries, obesity is highly prevalent and a growing problem. The UK currently has the highest prevalence in Europe. Around one quarter of the population are obese, and many more are overweight. Obesity is responsible for a significant degree of morbidity and mortality.

NICE guidance [CG189] recommends that surgery should be considered for morbidly obese people and for those in whom other weight-loss options were unsuccessful. The most commonly performed operations are laparoscopic adjustable gastric banding, laparoscopic gastric bypass, and sleeve gastrectomy. All of these lead to weight loss, but they are associated with different problems and long-term implications.

Endoscopic obesity treatments have been available for some time, but are predominantly used in the USA, where their lower costs (compared to surgery) make bariatric treatment more affordable to self-paying patients. Worldwide and UK-uptake is increasing though, due to improved technologies. Although numbers are still low in the NHS, most bariatric surgeons anticipate these procedures will become a bridge, if not an alternative, to surgery.

There is a significant body of evidence available from research and clinical data. Some of this has been reviewed in evidence syntheses with narrow inclusion criteria that make it difficult to compare the interventions with each other and across patient groups and treatment regimens (e.g. stand-alone treatment, endoscopic treatment prior to surgery, weight-loss intervention to improve type 2 diabetes etc.). Other evidence may not have been considered in previous reviews.

Hence, an overarching evidence synthesis is needed to establish the evidence of all currently available endoscopic obesity treatments. In addition, a cost-effectiveness analysis is required. The HTA programme intends to fund the study outlined above, in order to provide timely evidence to guide patients, doctors, and NHS Trusts, and to inform future clinical guidance.
The Programme Oversight Committee has estimated that the cost of this work will be around £200,000. 

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

If you wish to submit a Stage 1 application for this call, the online application form can be found on the Funding opportunities page.  To select this call, use the filters on the right of the screen or search using the call name and/or number.

Your application must be submitted on-line no later than 1pm on the 23rd September 2020. Applications will be considered by the HTA Funding Committee at its meeting in November 2020.

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

IMPORTANT: Shortlisted Stage 1 applicants will be given eight weeks to submit a Stage 2 application. The Stage 2 application will be considered at the Funding Committee in March 2021.

Applications received electronically after 1300 hours 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 (i) each application needs to state the case as to why the same person is included (ii) the shared co-applicant should not divulge application details between teams and (iii) both teams should acknowledge in their application that they are aware that one of their co-applicants is part of a competing application and that study details have not been shared. 

Should you have any queries please contact us