ECO 2026: Body Composition (DXA) Changes During 6-Month Withdrawal from Semaglutide and/or Bimagrumab Treatment of Adults with Obesity: The BELIEVE Study Extension

Presenter

Aronne, L. J

Bimagrumab (bima), an antibody to activin type 2 receptors, blocks activin/myostatin pathways, increasing skeletal muscle and reducing fat mass; in combination with semaglutide (sema), a GLP‑1RA, additive fat loss and muscle preservation have been observed.

BELIEVE was a Phase 2, double-blind, placebo-controlled trial involving 507 adults with overweight or obesity. Participants were randomized into nine groups: placebo; bima monotherapy (10 or 30 mg/kg IV every 12 weeks); sema monotherapy (1.0 or 2.4 mg SC weekly); and their respective combination regimens. After 48 weeks, open-label active treatment continued through week 72, followed by post-treatment follow-up to week 104. Total body fat mass, lean mass, and estimated abdominal visceral adipose tissue (VAT) were assessed by DXA throughout the study, including at week 96

At Week 72, % change in weight was −10.8% (bima 30), −15.7% (sema 2.4), −22.1%; fat mass −28.5%, −27.8%, −45.7%, respectively. Lean mass increased with bima, decreased with sema, and was largely preserved with combined treatment. VAT reduction was greater with bima 30 (−45.1%) vs sema 2.4 (−35.8%) and further reduced (−58.2%). At Week 96 (N=288), weight change was −9.0% vs −9.1%, indicating greater regain after sema withdrawal. Fat mass remained −18.8% vs −17.7%. Lean mass gains with bima (+2.5%) reversed (−2.1% vs BL), while sema-associated loss (−7.4%) partially recovered (−4.1% vs BL).

Following 6-month treatment withdrawal, lean mass returned to baseline post-bima, as expected. Partial weight regain after semaglutide withdrawal showed a similar fat:lean ratio as weight loss, suggesting no preferential fat regain.

ECO 2026: European Obesity Management Competency Framework

Presenter

Contreras, F

A mixed-methods, consensus-informed initiative developed the European Obesity Management Competency Framework to address fragmented obesity education across Europe.

The final framework includes five domains and 28 core competencies with enabling competencies across foundational science, clinical care, communication and care environments, multidisciplinary practice, and system-based policy. It embeds obesity as a chronic disease, incorporates weight stigma as a determinant of care quality, and emphasises person-centred and multidisciplinary approaches. Benchmarking against existing frameworks and iterative refinement ensured alignment with contemporary evidence and education models. The framework supports consistent skill development and clinical application across healthcare settings.

The framework provides the first harmonised postgraduate competency model, enabling standardised training, reducing variability in care, addressing stigma, and supporting equitable, evidence-based obesity management across European healthcare systems.

European Obesity Management Competency Framework: Domains and Core Competencies

Domain	Key Competencies
Foundation of obesity	Apply epidemiology, weight regulation, and obesity mechanisms in clinical and population care Assess biological, genetic, environmental, psychological, and treatment-related causes Recognize obesity as a chronic disease and manage using long-term care models Address stigma and bias impacting care delays and outcomes Consider variability in obesity to guide risk, prognosis, and treatment decisions
Obesity Assessment, Clinical Care & Management	Perform clinical assessments aligned with patient needs, care context, and defined scope of practice Utilise validated tools for diagnosis, staging, and risk stratification of obesity and related complications Recognise and evaluate biological, behavioural, psychological, environmental, and iatrogenic determinants of obesity to guide management and referral pathways Integrate patient-reported outcomes and individual goals into clinical evaluation and therapeutic decision-making Implement evidence-based obesity management approaches across psychological, behavioural, nutritional, pharmacological, and surgical interventions Assess benefits, risks, adverse effects, limitations, and evidence strength for each treatment modality Integrate clinical findings to tailor management plans and identify the need for specialist referral or multidisciplinary team involvement Identify and manage urgent or evolving obesity-related complications appropriately within the scope of practice
Communication & Care environment	Exhibit respectful, non-stigmatising communication that recognises obesity as a disease Identify, evaluate, and address personal, professional, and systemic contributors to weight stigma within clinical practice Establish and sustain a care environment that upholds dignity, respect, and psychological safety Enable shared decision-making by integrating clinical evidence with patient values and lived experiences Adapt communication strategies in response to patient feedback and clinical outcomes
Multidisciplinary & integrated care	Navigate and apply integrated obesity care pathways across healthcare settings Coordinate access to appropriate disciplines according to patient needs Undertake or engage in care coordination roles within obesity care pathways as required Enhance multidisciplinary team (MDT) functioning by defining roles, referral thresholds, and responsibilities Assess the efficiency and effectiveness of multidisciplinary care delivery
System-based practice & Policy	Examine the social, commercial, and economic factors that shape obesity risk, access to care, and health outcomes Promote equitable, needs-based access to evidence‑informed obesity care Assess policy and system‑level interventions, acknowledging their limitations, evolving evidence base, and context-specific differences Implement quality assurance and continuous improvement approaches within obesity services and care pathways Assist patients in navigating healthcare systems, particularly those affected by structural, financial, or social barriers

 

ECO 2026: EASO/EFAD Position Statement on Nutritional Considerations for Incretin-Based Therapies in Obesity Management

Presenter

Tolvanen, L

A consensus statement by European Association for the Study of Obesity (EASO) and European Federation of the Associations of Dietitians (EFAD) evaluated nutritional considerations during incretin-based therapies, focusing on Medical Nutrition Therapy (MNT) by Registered Dietitians (RDs).

Reduced appetite and early satiety lower energy intake but increase risk of inadequate protein intake, micronutrient deficiencies, and dehydration. MNT supports dietary quality, symptom management (nausea, constipation, diarrhoea), and development of regular eating patterns and mindful eating. It also addresses food insecurity, weight-loss expectations, plateaus, and preparation for treatment discontinuation. Multidisciplinary monitoring improves safety and effectiveness.

Individualised MNT is integral to obesity pharmacotherapy, helping prevent nutritional deficiencies, mitigate gastrointestinal adverse events, preserve lean mass, and support sustainable long-term weight management.

ECO 2026: Semaglutide Reduces Body Weight Regardless of Menopause Status: STEP and OASIS 4 Post Hoc Analysis

Presenter

Palacios, S

This post hoc analysis of Semaglutide Treatment Effect in People with obesity (STEP)  (n=2151) and Oral Semaglutide in Adults with Overweight or Obesity (OASIS 4)  (n=151) trials evaluated semaglutide (2.4 mg weekly s.c. for 68 weeks; 25 mg oral daily for 64 weeks) on anthropometric outcomes in women with overweight/obesity without diabetes, stratified by menopause status.This was determined based on the response to “Has the participant gone through menopause?”, medical history, and age. Pre-menopause pts responded “No,” had no history of menopause, and were aged <45 years; peri-menopause pts responded “No,” had no history of menopause, and were aged 45–54 years; post-menopause pts either responded “Yes,” had documented menopause, or were aged ≥55 years.

In STEP, median body weight reduction was −18.0%, −17.7%, and −16.4% in the pre-, peri-, and post-menopause groups, respectively; similar trends were observed in OASIS 4 (−18.1%, −15.6%, −15.6%). The proportion achieving ≥10% weight loss in STEP was 74.7%, 78.7%, and 74.8%, and in OASIS 4 was 65.1%, 77.4%, and 63.3% across the respective groups. Waist circumference decreased by −18.5, −17.7, and −15.9 cm in STEP and −17.7 (13.5), −15.3 (8.6), and −13.5 (10.3) cm in OASIS 4. WHtR risk improvement reached 17.1%, 14.2%, and 9.1% in STEP and 19.0%, 9.7%, and 8.3% in OASIS 4, respectively.

Semaglutide produced clinically meaningful, consistent weight loss and anthropometric improvements irrespective of menopause status.

33^rd European Congress on Obesity (ECO 2026), 12^th -15^th May 2026, Istanbul, Turkey.