Intensive Weight Loss Intervention Versus Usual Care for Adults With Severe and Complex Obesity

Not Applicable

Recruiting

• Conditions: Obesity
• Interventions: Behavioral: Usual care; Behavioral: Intensive weight loss intervention

• Registration Number: NCT06321458
• Lead Sponsor: Carsten Dirksen

Brief Summary

In this trial, the aim is to assess the clinical benefits and harms, as well as cost-effectiveness of an intensive weight loss (IWL) intervention that includes total dietary replacements, behavioural support and weight-loss medication compared with existing weight management programmes within primary care for people with severe and complex obesity.

Detailed Description

In the LightWAY trial, an intensive weight loss (IWL) intervention will be compared with with usual care. The IWL lasts two years, and includes total dietary replacements, behavioural support, and weight loss medication in three phases:

* Induction' phase (week 0-12 after randomisation): total dietary replacement (TDR) programme and behavioural support with weight loss medication (WLM) if rate of weight loss is insufficient.

* Weight loss continuation' phase (week 13-32 after randomisation): progression of dietary programme including reduction in use of TDR products, reintroduction of healthy foods, with behavioural support, introduction of physical activity, WLM (as required).

* Maintenance' phase (week 33-104 after randomisation): Continued healthy diet and physical activity with WLM (if required), with return to induction phase if weight regain occurs induction, weight loss continuation, maintenance.

Usual care will differ between the two countries (Denmark and the United Kingdom).

In Denmark, participants will receive a pamphlet on current obesity management guidelines from the Danish National Board of Health, and will be advised to contact their GP for potential referral to local municipality-based obesity management programmes. Furthermore, a notification will be sent to the participant's GP, informing that the participant has been enrolled in the trial and is randomised to usual care. The availability and structure of current obesity programmes varies between municipalities.

In the United Kingdom, participants are eligible for referral into an NHS Tier 3 weight management service. These services are commissioned by integrated care boards, and can therefore differ slightly across the 42 regions within the UK. These are specialist weight management clinics that provide non-surgical, intensive medical management with a multidisciplinary approach to care. These clinics often consist of specialist doctors, nurses, dieticians and physiotherapists/exercise therapists, and include psychological support.

Study Timeline

• Study First Submitted: 2024-03-13
• Study First Submitted QC: 2024-03-19
• Study First Posted: 2024-03-20
• Study Start: 2024-04-29
• Status Verified: 2025-05
• Last Update Submitted: 2025-05-14
• Last Update Posted: 2025-05-15
• Primary Completion: 2027-12
• Study Completion: 2048-12

Recruitment & Eligibility

• Status: RECRUITING
• Sex: All
• Target Recruitment: 600

Inclusion Criteria

1. Age ≥18 years and ≤60 years old at screening.
2. Has severe and complex obesity i.e. BMI>35 or >32.5 in people with South Asian, Chinese, other Asian, Middle Eastern, Black African or African-Caribbean family backgrounds and with one or more of these specific adiposity-related chronic diseases of cardiovascular disease, type 2 diabetes, hypertension, non-alcoholic steatosis, or sleep apnoea.
3. Provides informed consent.

Exclusion Criteria

1. Intending to become pregnant in the next two years or pregnant or breastfeeding.
2. Use of WLM or GLP-1 agonist treatment within the last three months.
3. Currently being treated for cancer other than oestrogen antagonist therapy or non-melanoma skin cancer.
4. Prior bariatric surgery, not including laparoscopic gastric banding, intragastric balloons or duodenal-jejunal bypass sleeve (Endobarrier™ or similar) if the device has been removed >1 year before screening.
5. Diagnosis of or treatment for severe eating disorder within the last 6 months.
6. Any other disease that markedly compromises the participant's ability to adhere to the treatment programme or follow-up or is likely to mean that weight loss will not improve the person's length or quality of life, such as conditions limiting life expectancy.
7. Conditions that contraindicate or complicate TDR (including type 1 diabetes or other diabetes requiring insulin therapy, phenylketonuria, or other conditions requiring special diets).
8. Conditions that contraindicate or complicate GLP-1 treatment (including history of pancreatitis)
9. Taking part in other research involving multidisciplinary obesity treatment would compromise participation in this trial.
10. Another member of the household enrolled in the trial.

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Usual care	Usual care	Denmark: usual care offered by the GP or local municipality. The UK: tier 3 weight management services.
Intensive weight loss intervention	Intensive weight loss intervention	The 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.

Primary Outcome Measures

Name	Time	Method
MetS-Z	104 weeks after randomisation	Metabolic syndrome severity Z-score (scale from -4 to 4, mean is 0, higher scores indicate a worse outcome)
Weight	104 weeks after randomisation	Weight (kg)

Secondary Outcome Measures

Name	Time	Method
Short-Form-36, mental component score	104 weeks after randomisation	Quality of life, SF36-mental component score (scale from 0-100, higher scores indicate better mental health)
Gait speed	104 weeks after randomisation	4-metre gait speed (m/s)
Weight loss (20%)	104 weeks after randomisation	Proportion of participants with weight loss ≥20%

Trial Locations

Locations (10)

University Hospitals Birmingham NHS Foundation Trust; 🇬🇧 Birmingham, United Kingdom

University Hospitals of Derby and Burton NHS Foundation Trust; 🇬🇧 Derby, United Kingdom

East of England RRDN; 🇬🇧 Ipswich, United Kingdom

Yorkshire and Humber RRDN (Leeds, Sheffield and Hull); 🇬🇧 Leeds, United Kingdom

Powys Teaching Health Board; 🇬🇧 Powys, United Kingdom

Frederiksberg kommune: Social-, Sundheds- og Arbejdsmarkedsområdet; 🇩🇰 Frederiksberg, Denmark

The Parker Institute, Copenhagen University Hospital - Bispebjerg and Frederiksberg; 🇩🇰 Frederiksberg, Denmark

Hvidovre kommune: Center for Sundhed og Ældre, Hvidovre Sundhedscenter, Sundhed og Forebyggelse; 🇩🇰 Hvidovre, Denmark

The Department of Medicine and the Gastro Unit, Copenhagen University Hospital - Amager and Hvidovre; 🇩🇰 Hvidovre, Denmark

Gladsaxe kommune: Social- og Sundhedsforvaltningen, Sundhed og Rehabilitering; 🇩🇰 Søborg, Denmark