SCALE Kids published: liraglutide lowers BMI in children aged 6 to under 12

The New England Journal of Medicine published SCALE Kids in its February 6, 2025 print issue, a phase 3a randomized trial testing the daily GLP-1 injection liraglutide in children aged 6 to under 12 years with obesity ^[1]. After 56 weeks, average body-mass index fell 5.8 percent in the liraglutide group and rose 1.6 percent in the placebo group ^[1][2].

The trial randomly assigned 82 children in a 2-to-1 ratio: 56 received once-daily subcutaneous liraglutide at 3.0 mg (or the highest dose they could tolerate) and 26 received placebo ^[1]. Both groups also received lifestyle interventions. The treatment period ran 56 weeks and was followed by a 26-week off-drug follow-up period ^[1]. The study was funded by Novo Nordisk and is registered as NCT04775082 ^[1].

What the numbers showed

The primary endpoint was percentage change in BMI. The estimated difference between groups was −7.4 percentage points (95 percent confidence interval, −11.6 to −3.2; P<0.001) ^[1][2].

Body weight is a more complicated measure in growing children, and the trial reflects that. Mean body weight rose 1.6 percent in the liraglutide group and 10.0 percent in the placebo group over the 56 weeks — an estimated difference of −8.4 percentage points (95 percent CI, −13.4 to −3.3; P=0.001) ^[1][2]. In other words, children on liraglutide still gained a small amount of weight on average, but far less than those on placebo, while their height continued to increase, which is why BMI dropped.

A BMI reduction of at least 5 percent occurred in 46 percent of the liraglutide group versus 9 percent of the placebo group (adjusted odds ratio 6.3; 95 percent CI, 1.4 to 28.8; P=0.02) ^[1][2].

Side effects were common in both arms. Adverse events of any kind were reported in 89 percent of liraglutide participants and 88 percent of placebo participants ^[1]. Gastrointestinal side effects were clearly more frequent with the drug: 80 percent versus 54 percent ^[1][2]. Serious adverse events were reported in 12 percent of the liraglutide group and 8 percent of the placebo group ^[1]. With only 82 children enrolled, the confidence intervals around several of these estimates are wide, and the trial was not designed to detect rare harms.

Why it matters for patients

For US families, the central practical fact has not changed: as the study authors state, no medications are currently approved for treating nonmonogenic, nonsyndromic obesity in children younger than 12 years of age ^[1][2]. SCALE Kids is evidence that a GLP-1 drug can lower BMI in this age group, but it is not an approval, and the sources do not indicate that any regulator has acted on these data.

It also matters which drug was tested. Liraglutide is a once-daily injection and is a different molecule from semaglutide (Ozempic, Wegovy, Rybelsus) or tirzepatide (Mounjaro, Zepbound). Results from one GLP-1 medicine in one age group do not automatically transfer to another.

The trial is small — 26 children in the comparison group — and lasted 56 weeks with a 26-week follow-up ^[1]. Longer-term effects on growth, puberty, bone development, and what happens to BMI after stopping are not described in the abstract text available here, so those questions remain open. The high rate of gastrointestinal side effects in children, 80 percent, is the most consistent safety signal reported ^[1][2].

Cost and coverage for pediatric use are not addressed in the published trial materials.

What happens next

The paper was first published online September 10, 2024, then appeared in the February 6, 2025 issue of the New England Journal of Medicine, volume 392, number 6, pages 555–565 ^[1]. It drew enough attention to prompt four pieces of published correspondence in the journal on May 8, 2025, including a reply from the trial authors — a sign that clinicians are actively debating how to interpret and apply the findings ^[2].

Whether these results lead to a regulatory filing or a label expansion for children under 12 is not stated in the sources.