WHO issues first global guidance on GLP-1 drugs for obesity

The World Health Organisation has published its first guideline on the use of GLP-1 receptor agonists for obesity, concluding that the drugs are effective over the long term when paired with lifestyle changes, but cautioning that global access must improve.

In the document, the WHO makes two key recommendations. First, GLP-1 medicines may be used as long-term treatment, defined as six months or more, for adults living with obesity, based on evidence of moderate certainty. Second, anyone prescribed these drugs should also receive counselling on diet, physical activity and other behavioural changes, although evidence supporting this recommendation is of low certainty.

The guidance covers treatments including tirzepatide (Zepbound), semaglutide (Wegovy), and liraglutide (Saxenda). These medicines are recommended for adults with a body mass index of 30 or above.

Writing in JAMA, Francesca Celletti of the WHO and colleagues said the advice reflects a growing recognition of obesity as “a chronic, relapsing disease that requires lifelong care”. GLP-1 agonists, they added, represent “more than a scientific breakthrough”, signalling a shift in how societies understand and address obesity, no longer as a simple lifestyle problem, but as a complex, preventable and treatable condition.

WHO Director-General Dr Tedros Adhanom Ghebreyesus welcomed the arrival of new treatments but stressed that they were not a substitute for healthy living. “These new medicines are powerful clinical tools offering hope to millions. But let me be clear: medicine alone will not solve the obesity crisis,” he told reporters. Obesity, he said, has “many social, commercial, and environmental determinants requiring action in many sectors, not only in the clinic”.

More than one billion people globally live with obesity, which Dr Tedros described as “one of the most serious public health challenges of our time”. According to WHO figures, 3.7 million deaths last year were related to obesity, accounting for around twelve per cent of all deaths caused by non-communicable diseases. By 2030, the number of people affected is expected to reach two billion.

GLP-1 receptor agonists have been used for more than two decades to treat type 2 diabetes and were added to the WHO’s list of essential medicines for high-risk patients last year. More recently, semaglutide and tirzepatide have shown significant effects on weight loss, leading to regulatory approvals for obesity treatment in 2021 and 2023.

However, the WHO warns that the drugs’ potential is limited by high costs, manufacturing constraints and supply-chain issues. Implementing the new recommendations will depend on three main factors: expanding fair access to affordable GLP-1 therapies, ensuring health systems can integrate these treatments with high-quality obesity care and delivering services that are person-centred, non-discriminatory, and geared towards universal access.

“Our greatest concern is equitable access,” Dr Tedros said. Even in the most optimistic scenarios, current global production would supply only around 100 million people, fewer than ten per cent of those living with obesity worldwide. Without urgent action, he warned, the medicines risk widening inequalities both within and between countries.

Strategies to increase availability could include generic manufacturing once patents expire, the patent for semaglutide is due to end next year, along with pooled procurement, tiered pricing, voluntary licensing and expanding oral formulations to ease production and distribution.

The WHO describes the recommendations as conditional, indicating that the balance of benefits and drawbacks may vary depending on individual, clinical and public-health circumstances. Celletti and colleagues point to gaps in long-term data on safety, dosing, maintenance and discontinuation, as well as concerns over cost, health-system capacity and equity.

Evidence that intensive behavioural therapy can improve weight-loss outcomes when combined with GLP-1 treatment is also limited. The guideline applies only to adults living with obesity and does not cover adults who are living with overweight with related health conditions, despite the fact that GLP-1 agents are authorised for use in such cases in some countries.

The WHO said the obesity guidance will be updated as new evidence emerges. A separate guideline addressing the use of GLP-1 therapies in children living with obesity is expected soon.