The case for GLP-1s in adolescents with obesity now rests on several randomised trials and two marketing authorisations. Real-world data are growing too. That evidence shows substantial reductions in body mass index over 56 to 68 weeks. It says much less about years of growth, puberty and adult life. Meanwhile, trials have moved down the age range faster than long-term answers have arrived. Detailed semaglutide data in children aged six to under 12 are due in November 2026.
Why GLP-1s in Adolescents Became a Prescribing Question
Use has risen quickly from a low base. A CDC analysis published in June 2025 examined US adolescents aged 12 to 17 with obesity. In 2023, 0.5 per cent were prescribed an obesity medication. The dataset covered 93,121 adolescents with obesity that year, of whom 427 received a prescription. After adjustment, the proportion in 2023 was 301.7 per cent higher than in 2020. Most of those treated, 82.9 per cent, had severe obesity.
Dispensing data point the same way. A 2024 JAMA research letter from the University of Michigan examined people aged 12 to 25. Monthly GLP-1 dispensing in that group rose 594 per cent between 2020 and 2023. Ozempic dispensing also rose, although it is not approved for weight management at any age. Senior author Kao-Ping Chua said this pointed to “increasing off-label use of Ozempic” for weight management in young people.
The American Academy of Pediatrics added momentum in January 2023. Its clinical practice guideline said paediatricians should offer weight loss pharmacotherapy to adolescents aged 12 and older with obesity. That offer sits alongside health behaviour and lifestyle treatment, not in place of it. The guideline gave prescribers a framework for using GLP-1s in adolescents rather than treating them as exceptional.
The Trial Evidence for GLP-1s in Adolescents
Liraglutide: the first licence
SCALE Teens, published in 2020, randomised 251 adolescents aged 12 to under 18 to liraglutide 3.0 mg or placebo. Treatment ran for 56 weeks after a 12-week lifestyle run-in. The difference in BMI standard deviation score was minus 0.22 in favour of liraglutide. At least 5 per cent BMI reduction occurred in 43.3 per cent on liraglutide. The placebo figure was 18.7 per cent.
Gastrointestinal adverse events were reported by 64.8 per cent on liraglutide and 36.5 per cent on placebo. BMI rose again during the 26-week off-treatment period. Lead author Aaron Kelly described the degree of BMI reduction as “clinically meaningful”. The FDA approved liraglutide for weight management in adolescents in 2020.
Semaglutide: the second licence
STEP TEENS changed the scale of the debate. The trial was published in the New England Journal of Medicine in November 2022. It randomised 201 adolescents 2:1 to semaglutide 2.4 mg weekly or placebo. Both arms received lifestyle intervention for 68 weeks. Mean age at baseline was 15.4 years.
BMI fell 16.1 per cent with semaglutide and rose 0.6 per cent with placebo. The estimated treatment difference was minus 16.7 percentage points (95 per cent CI minus 20.3 to minus 13.2). Weight loss of at least 5 per cent was reached by 73 per cent on semaglutide. Only 18 per cent on placebo did so. Investigators also reported improvements in waist circumference, HbA1c, several lipid measures and ALT.
For GLP-1s in adolescents, the safety profile broadly tracked the adult programme. Gastrointestinal events occurred in 62 per cent on semaglutide and 42 per cent on placebo. Five semaglutide participants (4 per cent) developed cholelithiasis, against none on placebo. Serious adverse events were reported in 11 per cent and 9 per cent respectively. Novo Nordisk funded the trial. The FDA extended Wegovy to adolescents aged 12 and over shortly after publication.
Tirzepatide: diabetes first, obesity pending
Eli Lilly’s dual GIP and GLP-1 agonist has reached younger patients through type 2 diabetes rather than obesity. SURPASS-PEDS randomised 99 participants aged 10 to under 18 whose diabetes was inadequately controlled on metformin, basal insulin or both. At 30 weeks, HbA1c fell 2.2 percentage points across pooled tirzepatide doses. BMI fell 11.2 per cent on the 10 mg dose, against 0.4 per cent on placebo, under the efficacy estimand.
Results were published online in The Lancet in September 2025. Tirzepatide is now indicated for type 2 diabetes from age 10 in the US and the UK. Its weight management indication remains limited to adults. SURMOUNT-ADOLESCENTS-1 (NCT06075667), the dedicated obesity trial, listed May 2026 as its expected primary completion. A search on 25 October 2026 found no published topline results.
What the Pooled Data Say About Safety
A systematic review and meta-analysis in JAMA Pediatrics, published online in September 2025, pooled 18 randomised trials. These involved 1,402 participants aged 6 to 17 with obesity or type 2 diabetes. GLP-1 receptor agonists reduced BMI by 1.45 units overall and by 1.71 units in the obesity trials.
Gastrointestinal adverse events were significantly more common than on placebo. However, rates of depression and suicidal ideation or behaviour did not differ significantly. Nor did hepatobiliary disorders or discontinuations due to adverse events. The authors noted that gastrointestinal effects remain a consideration for long-term use. Separately, the EMA’s safety committee reviewed GLP-1 receptor agonists in April 2024. It concluded that the available evidence does not support a causal association with suicidal or self-injurious thoughts and actions. That review was not specific to young people.
Real-world data are adding a nutritional signal. A study in Childhood Obesity was published on 17 September 2026. It followed 2,031 US patients aged 10 to 17 starting GLP-1 therapy. Within one year, 16.8 per cent had at least one nutritional deficiency. Vitamin D deficiency was the most frequent, at 12.4 per cent. Only 23.3 per cent received nutrition therapy or counselling within 180 days.
The cohort differs from the obesity trials. Around two thirds had type 2 diabetes, and 78.6 per cent started on liraglutide. Even so, senior author Justin Ryder of Ann and Robert H. Lurie Children’s Hospital of Chicago said wider paediatric use means “we need to understand the risks”.
Moving Down the Age Range
Two trials now cover children aged six to under 12. SCALE Kids randomised 82 children to liraglutide or placebo for 56 weeks. BMI fell 5.8 per cent on liraglutide and rose 1.6 per cent on placebo. A BMI reduction of at least 5 per cent occurred in 46 per cent and 9 per cent respectively. Lead author Claudia Fox said: “To date, children have had virtually no options for treating obesity.”
Novo Nordisk reported first STEP Young results in September 2026. The trial randomised 165 children to semaglutide or placebo for 68 weeks. More than 85 per cent had class II or III obesity at baseline. At week 68, 40.4 per cent on semaglutide no longer met the obesity threshold, against none on placebo.
That figure rests on the trial product estimand, which assumes every child adhered to treatment. The company has not yet released the mean BMI change. It said safety was consistent with earlier trials, with no concerns identified for growth or pubertal development. Chief scientific officer Martin Holst Lange said the company was “encouraged by the positive STEP Young results”. Full data are due at ObesityWeek 2026 in Washington DC, from 14 to 17 November.
No GLP-1 receptor agonist is currently authorised for weight management in children under 12 in the US or UK. In the EU, the Saxenda licence now covers children aged six to under 12 weighing at least 45 kg. The wider licence picture is tracked in the GLP-1 indications regulatory status map.
Off-label prescribing in the US has already reached younger children. A study in Pediatrics, published online on 4 September 2026, drew on national electronic health records. GLP-1 prescribing for children aged 8 to 11 with obesity, and no diabetes, rose 310-fold between 2019 and 2026. Over that period, 20,282 children in the age group received a prescription. Of these, 93.7 per cent had severe obesity.
The UK Position on GLP-1s in Adolescents
The domestic need is large. The National Child Measurement Programme reported on 2024/25 in England. It found 22.2 per cent of Year 6 children living with obesity. Wegovy and Saxenda both carry adolescent indications in the UK. The Wegovy summary of product characteristics covers adolescents aged 12 and above with obesity and body weight above 60 kg. Treatment should then be reviewed after 12 weeks at the maintenance or maximum tolerated dose. It should stop if BMI has not fallen by at least 5 per cent. The Saxenda label carries similar criteria, with a 4 per cent threshold.
Licensing has not translated into national NHS guidance. NICE terminated its appraisal of semaglutide for young people aged 12 to 17 in July 2023 (TA910). The company had confirmed it did not intend to make an evidence submission. The equivalent appraisal of liraglutide (TA749) was also terminated. As a result, access depends on specialist paediatric services and local funding decisions.
What the Evidence Does Not Yet Show
The most important gaps around GLP-1s in adolescents concern time. The pivotal adolescent trials lasted 56 to 68 weeks, while obesity in this population can persist for decades. SCALE Teens showed BMI rising after treatment stopped. Growth and pubertal outcomes have so far been reported only within trial periods.
Fatima Cody Stanford of Harvard Medical School told PolitiFact the evidence was “shorter-term than we would ideally like”. She noted that the disease often begins in childhood. Trial populations were also selected and closely supported, unlike many patients now receiving prescriptions.
Several readouts should sharpen the picture over the next year. The full STEP Young dataset will show the size of the effect in younger children. SURMOUNT-ADOLESCENTS-1 will test tirzepatide directly in adolescent obesity. For now, the evidence on GLP-1s in adolescents is strong on short-term efficacy and broadly consistent on short-term safety. It remains incomplete on what decades of treatment, or stopping it, will mean.
