Liraglutide Safely Reduces BMI in Children Ages 6-11 With Obesity in First-Ever Randomized Trial

What the researchers found

At week 56, liraglutide 3.0mg daily produced significantly better outcomes than placebo:

- BMI change: -5.8% vs +1.6% (difference: -7.4 percentage points, P<0.001)

- Body weight change: +1.6% vs +10.0% (difference: -8.4 percentage points, P=0.001)

- ≥5% BMI reduction: 46% vs 9% (adjusted OR 6.3, P=0.02)

Note that children in both groups gained weight (they're growing), but liraglutide children gained dramatically less. Adverse events were similar overall (89% vs 88%), but GI events were higher with liraglutide (80% vs 54%). Serious adverse events: 12% liraglutide vs 8% placebo.

Why it matters

Childhood obesity is a growing epidemic with lifelong health consequences, yet no medications are approved for children under 12. This NEJM trial provides the first randomized evidence that a GLP-1 peptide drug is effective in this young age group, potentially opening the door to earlier pharmacological intervention before metabolic complications become entrenched.

How the study worked

Phase 3a randomized, double-blind, placebo-controlled trial (SCALE Kids). 82 children aged 6 to <12 years with obesity were randomized 2:1 to liraglutide 3.0mg (or maximum tolerated dose) or placebo, both with lifestyle interventions. 56-week treatment period followed by 26-week follow-up. Primary endpoint: percentage change in BMI. (NCT04775082, funded by Novo Nordisk.)

What this study cannot tell us

Small sample size (n=82) limits the ability to detect rare adverse events. Short treatment duration (56 weeks) — long-term safety in growing children is unknown. High rate of GI adverse events (80%) raises tolerability concerns. The study was funded by Novo Nordisk (liraglutide's manufacturer). Children were still growing, making BMI change interpretation complex. The 26-week follow-up period will be important for understanding weight trajectory after stopping treatment.

How to read the evidence

This is a phase 3a randomized, double-blind, placebo-controlled trial published in the New England Journal of Medicine — the gold standard of clinical evidence. Despite the small sample size (n=82), the rigorous design and statistically significant results across primary and confirmatory secondary endpoints provide strong evidence for liraglutide's efficacy in this age group.

When this study was published

Published in 2025 in NEJM, this is a landmark study as the first randomized controlled trial of any GLP-1 receptor agonist in children under 12 years of age.

The bigger picture

This trial represents the youngest age group in which a GLP-1 receptor agonist has been tested in a randomized controlled trial. As pediatric obesity rates continue to rise globally, the extension of peptide-based therapies to younger children could fundamentally change how childhood obesity is managed. However, the long-term effects of modulating incretin signaling during childhood development remain to be studied.

Questions still open

• What are the long-term effects of GLP-1 receptor agonist use during critical childhood developmental periods?
• Will semaglutide (more effective in adults) produce even better results in children under 12?
• Should GLP-1 agonists become first-line therapy for severe childhood obesity, or remain reserved for the most resistant cases?

Common questions

Read the original research

Liraglutide for Children 6 to <12 Years of Age with Obesity - A Randomized Trial.

The New England journal of medicine, 392(6), 555-565

Citation

Fox, Claudia K; Barrientos-Pérez, Margarita; Bomberg, Eric M; Dcruz, John; Gies, Inge; Harder-Lauridsen, Nina M; Jalaludin, Muhammad Yazid; Sahu, Kushal; Weimers, Petra; Zueger, Thomas; Arslanian, Silva. (2025). Liraglutide for Children 6 to <12 Years of Age with Obesity - A Randomized Trial.. The New England journal of medicine, 392(6), 555-565. https://doi.org/10.1056/NEJMoa2407379