Intensive Weight Loss Intervention Versus Bariatric Surgery for Adults With Severe and Complex Obesity: the LightBAR Randomised Trial
LightBAR
1 other identifier
interventional
500
2 countries
10
Brief Summary
With this trial, the aim is to assess the benefits and harms of a non-surgical intensive weight loss intervention that includes total dietary replacements, behavioural support and weight-loss medication compared with bariatric surgery for people with severe and complex obesity. The interpretation of the results will help inform future care pathways for people with obesity in whom bariatric surgery is currently the only available effective treatment option.
Trial Health
Trial Health Score
Automated assessment based on enrollment pace, timeline, and geographic reach
participants targeted
Target at P75+ for not_applicable obesity
Started May 2024
Longer than P75 for not_applicable obesity
10 active sites
Health score is calculated from publicly available data and should be used for screening purposes only.
Trial Relationships
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Study Timeline
Key milestones and dates
First Submitted
Initial submission to the registry
February 5, 2024
CompletedFirst Posted
Study publicly available on registry
March 13, 2024
CompletedStudy Start
First participant enrolled
May 8, 2024
CompletedPrimary Completion
Last participant's last visit for primary outcome
December 1, 2027
ExpectedStudy Completion
Last participant's last visit for all outcomes
December 1, 2048
February 11, 2026
February 1, 2026
3.6 years
February 5, 2024
February 9, 2026
Conditions
Outcome Measures
Primary Outcomes (1)
MetS-Z
Metabolic syndrome severity Z-score
104 weeks after randomisation
Secondary Outcomes (3)
Weight
104 weeks after randomisation
Gait speed
104 weeks after randomisation
Short-Form-36, mental component score
104 weeks after randomisation
Other Outcomes (55)
SAE
104 weeks after randomisation
Proportion of participants with at least one adverse events (AE) of special interest. Each of the AE will also be assessed individually exploratorily.
104 weeks after randomisation
Cardiometabolic health - metabolic syndrome
104 weeks after randomisation
- +52 more other outcomes
Study Arms (2)
Intensive weight loss intervention
EXPERIMENTALThe intensive weight loss intervention (IWL) includes total dietary replacements, behavioural support, and weight loss medication. The intervention consists of three phases: induction, weight loss continuation, maintenance, and it will lasts two years in total.
Bariatric surgery
ACTIVE COMPARATORBariatric surgery: Roux-en-Y Gastric Bypass (RYGB) or Sleeve Gastrectomy (SG)
Interventions
Roux-en-Y Gastric Bypass (RYGB) or Sleeve Gastrectomy (SG)
Intensive weight loss intervention, incl. total meal replacements, behavioural support, and weight loss medication
Eligibility Criteria
You may qualify if:
- Aged 18 to 60 years (inclusive) at time of screening.
- Eligible for and willing to undergo bariatric surgery, i.e., fulfilment of criteria for bariatric surgery from the respective national health authorities:
- DK: BMI ≥ 35 kg/m2 with one or more of the following: T2D, severe hypertension, sleep apnoea requiring treatment, symptomatic arthrosis in lower extremities, female infertility related to overweight, or BMI\>40 kg/m2 with other strong medical reasons for weight loss (28). Prior to surgery, an 8% weight loss is required as well as smoking cessation.
- UK: BMI of 35 kg/m2 to 40 kg/m2 and other significant disease (e.g., type 2 diabetes or high blood pressure), or BMI ≥40 kg/m2. Has been or is willing to receive intensive management in a specialist tier 3 obesity service (29).
- Fit for anaesthesia and surgery.
- Informed consent.
You may not qualify if:
- Prior bariatric or hiatal surgery, not including intragastric balloons or duodenal-jejunal bypass sleeve (Endobarrier™ or similar) if the device has been removed \>1 year before screening.
- Use of any WLM (including liraglutide and semaglutide for diabetes) within last 3 months.
- Conditions that contraindicate or complicate total diet replacement (including type 1 diabetes or other diabetes requiring basal bolus insulin therapy or insulin pump therapy (for Denmark) and any diabetes requiring insulin therapy (for UK), phenylketonuria, or other conditions requiring strict adherence to special diets).
- Conditions that contraindicate or complicate treatment with GLP-1 receptor analogues (including history of pancreatitis or known allergies).
- Conditions that contraindicate or complicate bariatric surgery (GI motility disorders, large abdominal wall hernia, large hiatus hernia (\>5cm), Crohn's disease, liver cirrhosis, or other conditions preventing laparoscopic bariatric surgery e.g. multiple previous abdominal surgery).
- Conditions that contraindicate or complicate study adherence and bariatric surgery (mental disorder, unstable psychiatric disease, recent history of alcohol/medication abuse, cancer treatment within 5 years).
- Pregnant or planning pregnancy in the next two years or currently breast feeding.
- Not achieving a 5% weight loss within 12 weeks prior to randomisation.
- People taking part in other research involving multidisciplinary obesity treatment that would compromise their participation in this trial.
- Another member of the household enrolled in the trial.
- Diagnosis of or treatment for severe eating disorder within the last 6 months.
Contact the study team to confirm eligibility.
Sponsors & Collaborators
- University of Southern Denmarkcollaborator
- University of Oxfordcollaborator
- Copenhagen Trial Unit, Center for Clinical Intervention Researchcollaborator
- Carsten Dirksenlead
- University of Copenhagencollaborator
Study Sites (10)
Steno Diabetes Center Aarhus, Aarhus Universitets Hospital
Aarhus, 8200, Denmark
The Department of Medicine and Department of Surgery, University Hospital of South West Jutland
Esbjerg, 6700, Denmark
The Department of Medicine and the Gastro Unit, Copenhagen University Hospital - Amager and Hvidovre
Hvidovre, 2650, Denmark
Department of Surgery, Viborg Regional Hospital
Viborg, 8800, Denmark
St Richard's Hospital
Chichester, Sussex, PO19 6SE, United Kingdom
Hartlands Hospital, University Hospitals Birmingham NHS Foundation Trust
Birmingham, B9 5SS, United Kingdom
Southmead Hospital, North Bristol NHS Trust
Bristol, BS10 5NB, United Kingdom
The Whittington Hospital
London, N19 5NF, United Kingdom
Sunderland Royal Hospital
Sunderland, SR4 7TP, United Kingdom
Musgrove Park Hospital, Somerset Foundation NHS Trust
Taunton, TA1 5DA, United Kingdom
Related Publications (1)
Tomova-Olsen SA, Kousgaard MB, Jensen KT, Reventlow S, Christiansen AL, Bojsen-Moller KN, Dirksen C, Overbeck G. Time, money, and weight loss: a qualitative study exploring patients' perspectives on randomization for bariatric surgery vs. an intensive non-surgical weight loss program. Trials. 2025 Apr 4;26(1):121. doi: 10.1186/s13063-025-08816-8.
PMID: 40186310DERIVED
Related Links
MeSH Terms
Conditions
Interventions
Condition Hierarchy (Ancestors)
Intervention Hierarchy (Ancestors)
Study Officials
- STUDY CHAIR
Carsten Dirksen, Ass Professor
Department of Medicine, Copenhagen University Hospital - Amager and Hvidovre
Central Study Contacts
Study Design
- Study Type
- interventional
- Phase
- not applicable
- Allocation
- RANDOMIZED
- Masking
- DOUBLE
- Who Masked
- INVESTIGATOR, OUTCOMES ASSESSOR
- Masking Details
- Due to the nature of the interventions, it will not be possible to blind the participants or the healthcare providers administering the interventions. Blinded outcome assessment will be employed for the primary outcome and anywhere else possible. When assessing clinical outcomes, the participants will be asked not to disclose their assigned intervention group to the outcome assessor. Further, they will be provided with a plain white t-shirt, or similar, to wear during clinical assessments to cover the presence of surgical scars. Statisticians and investigators drawing conclusions will be fully blinded. We will conduct the statistical analyses with the intervention groups coded as e.g., 'A' and 'B'. We will write two abstracts while the blinding is intact; one assuming the experimental intervention group is 'A' and the control intervention group is 'B', and one assuming the opposite. After these two abstracts have both obtained consensus, the code will be broken by the data manager.
- Purpose
- TREATMENT
- Intervention Model
- PARALLEL
- Sponsor Type
- OTHER
- Responsible Party
- SPONSOR INVESTIGATOR
- PI Title
- Associate Professor
Study Record Dates
First Submitted
February 5, 2024
First Posted
March 13, 2024
Study Start
May 8, 2024
Primary Completion (Estimated)
December 1, 2027
Study Completion (Estimated)
December 1, 2048
Last Updated
February 11, 2026
Record last verified: 2026-02
Data Sharing
- IPD Sharing
- Will share
- Shared Documents
- STUDY PROTOCOL, SAP
- Time Frame
- When the results have been published
- Access Criteria
- Researchers with a protocol for their planned study
After the results have been published, we aim to make a depersonalised dataset publicly available on e.g. ClinicalTrials.gov and/or the European Union (EU) Zenodo database (https://zenodo.org/). The final choice will reflect which platform(s) that are compliant with current legislation at that time.