The World Health Organization (WHO) has released its first guideline on the use of GLP-1 therapies for treating obesity in adults.

Obesity currently affects more than 1 billion people globally — a number projected to double by 2030, according to WHO. The organization defines obesity as having a BMI of 30 or higher in adults aged more than 19 years.

The new guideline “recognizes that obesity is a chronic disease that should be treated with comprehensive and lifelong care,” Francesca Celletti, MD, PhD, WHO senior adviser on obesity, told Medscape Medical News. It was developed in response to requests from WHO member states, and it’s a key deliverable under the WHO acceleration plan to stop obesity.

“The arrival of these medicines is a medical breakthrough,” Celletti said, “but without deliberate policies, access could exacerbate existing global health disparities.”

A special communication highlighting key points of the guideline was published simultaneously in JAMA.

Recommendations, Good Practice Statements

The guideline contains two key conditional recommendations based on evaluations of two GLP-1 receptor agonists (liraglutide and semaglutide) and one dual glucagon insulinotropic polypeptide (GIP)/GLP-1 agonist (tirzepatide). It also provides two good practice statements.

The first recommendation states that the drugs may be used by adults, excluding pregnant women, for the long-term treatment of obesity. This conditional recommendation is supported by moderate-certainty evidence due to limited data on long-term efficacy and safety, maintenance and discontinuation, current costs, inadequate health-system preparedness, and potential equity implications.

Intensive behavioral therapy may be provided as a co-intervention within a comprehensive multimodal clinical algorithm, according to the second recommendation. This is based on low-certainty evidence suggesting that such therapy may enhance treatment outcomes.

The two good-practice statements are:

1. Obesity is a chronic, complex disease requiring lifelong care, beginning with clinical assessment and early diagnosis. Once diagnosed, individuals should have access to comprehensive chronic care programs offering sustained behavioral and lifestyle interventions. 

   When appropriate, pharmacologic, surgical, or other therapeutic options may be used to support disease management. In parallel, care should address the prevention and treatment of obesity-related complications and comorbidities.

2. People living with obesity should receive context-appropriate counseling on behavioral and lifestyle changes — including, but not limited to, physical activity and healthy dietary practices — as a first step toward more structured behavioral interventions. For those prescribed the drugs, counseling on behavioral and lifestyle changes should be provided as a first step to intensive behavioral therapy to amplify and support optimal health outcomes.

‘A Societal Challenge’

Obesity is more than an individual challenge, according to WHO. The organization emphasized it’s also “a societal challenge that requires a fundamental reorientation of current approaches to a comprehensive strategy built with three pillars:

1. Creating healthier environments through robust population-level policies to promote health and prevent obesity;
2. Protecting individuals at high risk of developing obesity and related comorbidities through targeted screening and structured early interventions; and
3. Ensuring access to lifelong, person-centered care.”

Countries aiming for an inclusive implementation of the guideline face “a triple challenge,” Celletti said. “These include equitable access to affordable GLP-1 therapies; health-system readiness; and person-centered, nondiscriminatory universal access to care.”

The guideline calls on the global community to consider strategies to expand access, such as pooled procurement, tiered pricing, and voluntary licensing among others.

“While the introduction of this class of therapeutic agents is critical at this stage, selective and targeted treatment with medication alone cannot solve a crisis of this scale — what is needed is a comprehensive, system-wide response addressing prevention, care, and the underlying determinants of obesity,” Celletti said.

“Furthermore, WHO recommends the use of GLP-1 therapies only when clinically indicated and prescribed by a qualified healthcare provider,” she added. “Clinicians should inform people living with obesity and comorbidities about the risk related to inappropriate use and alert about the danger of falsified and substandard medical products procured outside [regulated] pathways.”

A separate WHO guideline on the management of obesity in children and adolescents is under development.

‘Welcome First Step’

John Wilding, professor of medicine and honorary consultant physician, Department of Cardiovascular and Metabolic Medicine, University of Liverpool, UK, commented on the guideline for the Science Media Centre. He said the guideline “should be broadly welcomed,” noting that it “reasserts the view that obesity is a chronic, relapsing disease that may require treatment, but also makes the important point that any strategy to curb the global obesity epidemic will require coordinated efforts in public health to look at food systems and the physical activity environment as well as improving access to treatment.

“I hope this will help focus WHO member states to consider how to improve access to comprehensive obesity care, and this is a welcome first step,” he concluded.

Marie Spreckley, research program manager and researcher specializing in weight management research and clinical practice at the University of Liverpool, UK, also commented. “A key strength is the emphasis on combining medication with behavioral support and on the need for equitable access, rather than presenting drugs as a stand-alone solution,” she said. The guideline “also avoids overspeculation by explicitly acknowledging supply constraints and the ethical and practical challenges of prioritization.” 

Wilding reported consultancy/advisory board work for the pharmaceutical industry contracted via the University of Liverpool in the past 36 months (no personal payment) for Alnylam, Amgen, AstraZeneca, Boehringer Ingelheim, Cytoki, Kailera, Lilly, Menarini, Metsera, Napp, Novo Nordisk, Pfizer, ProSciento, Response Pharmaceuticals, Rhythm Pharmaceuticals, Saniona, Shionogi, and YSOPIA; funding for clinical trials from Amgen, AstraZeneca, and Novo Nordisk; and personal honoraria/lecture fees from AstraZeneca, Boehringer Ingelheim, Medscape, Novo Nordisk, and Menarini. 

Wilding is past president of the World Obesity Federation and is a member of the Association for the Study of Obesity, Diabetes UK, European Association for the Study of Diabetes, American Diabetes Association, Society for Endocrinology, and the Rank Prize Funds Nutrition Committee. From 2009-2024, he was national lead for the Metabolic and Endocrine Specialty Group of the UK National Institute for Health and Care Research (NIHR) Clinical Research Network. 

Spreckley reported being the named holder and principal investigator of a University of Cambridge Public Engagement Starter Fund award for the AMPLIFY project; she also works on research programs funded by the NIHR. She has no personal financial links to manufacturers of GLP-1 therapies and has not received any industry funding.

Marilynn Larkin, MA, is an award-winning medical writer and editor whose work has appeared in numerous publications, including Medscape Medical News and its sister publication MDedge, The Lancet (where she was a contributing editor), and Reuters Health.