The main finding
In one sentence: In 82 children aged 6 to under 12 with obesity, 56 weeks of daily liraglutide (Saxenda, Victoza) plus lifestyle support lowered body mass index by 5.8% while placebo plus lifestyle support saw it rise by 1.6%, although mean body weight went up in both groups because the children were growing.
Group averages, not an individual prediction. A trial result describes what happened to a defined group over a defined time.
On this page
Why this study matters
Before this trial, no medicine had been tested in a large randomized trial for common obesity in children under 12. SCALE Kids is the first such trial of liraglutide in this age group. For Canadian parents and clinicians, it shows what the medicine did over about one year in young children, what side effects appeared, and why results in growing children must be read differently from results in adults.
Who was in the study
The trial enrolled 82 children aged 6 to under 12 years who had obesity. The abstract describes this as nonmonogenic, nonsyndromic obesity, meaning obesity not caused by a single known gene change or a genetic syndrome. 56 children were assigned to liraglutide and 26 to placebo. Treatment lasted 56 weeks and was followed by a 26-week follow-up period. The summary we reviewed does not state where the trial was run.
What the researchers did
This was a phase 3a randomized trial. Randomized means chance decided who got the medicine. Placebo is an injection that looks the same but contains no medicine. Children were assigned in a 2 to 1 ratio, so twice as many got liraglutide as placebo.
Children in the liraglutide group received a once-daily injection under the skin at a dose of 3.0 mg, or the highest dose they could tolerate if 3.0 mg was too much. Both groups received lifestyle interventions.
The primary outcome was the percentage change in body mass index (BMI). BMI compares weight with height. In children it is often used instead of weight alone, because children are expected to gain weight as they grow taller. The confirmatory secondary outcomes were the percentage change in body weight and a reduction in BMI of at least 5%.
What they found
At week 56, BMI changed by a mean of -5.8% with liraglutide and +1.6% with placebo (R32-C106). The estimated difference was -7.4 percentage points, with a 95% confidence interval of -11.6 to -3.2. A confidence interval is the range in which the true difference most likely sits. It does not include zero, so the result is unlikely to be due to chance.
| Outcome at week 56 | Liraglutide | Placebo | Difference (95% CI) |
|---|---|---|---|
| Change in BMI | -5.8% | +1.6% | -7.4 percentage points (-11.6 to -3.2) |
| Change in body weight | +1.6% | +10.0% | -8.4 percentage points (-13.4 to -3.3) |
| Reduction in BMI of at least 5% | 46% | 9% | adjusted odds ratio 6.3 (1.4 to 28.8) |
A key point for readers: mean body weight went up in both groups. Children on liraglutide gained 1.6% on average, and children on placebo gained 10.0% (R32-C106). Because the children were growing taller at the same time, BMI still fell in the liraglutide group. The medicine slowed weight gain rather than causing weight loss in most children.
Side effects and people who stopped
Side effects of any kind were very common in both groups: 89% with liraglutide and 88% with placebo. Stomach and bowel side effects were more common with liraglutide, at 80% compared with 54%. Serious side effects were reported in 12% of the liraglutide group and 8% of the placebo group.
The published summary we reviewed does not report how many children stopped treatment, or how many stopped because of side effects.
What this study does not tell you
- The trial was small, with 82 children and only 26 on placebo. Small trials give wide confidence intervals and cannot detect rare harms.
- A lower BMI in a growing child is not the same as weight loss in an adult. Mean weight still rose. Results cannot be compared with adult trials.
- Treatment lasted 56 weeks. The abstract does not report what happened during the 26-week follow-up after stopping.
- The summary we reviewed does not describe how missing data were handled.
- This is research evidence. It does not by itself mean the medicine is authorized in Canada for children under 12, and it is not a treatment recommendation for any child.
- The trial was funded by the maker of liraglutide.
What it means in Canada
This page describes one trial in young children. It does not say whether a medicine is right for any child. To learn about the medicine itself, see liraglutide in Canada. Information on what provincial plans pay for is at public drug coverage by province, and compare services shows how weight-management programs, including those for families, differ.
Common questions
Did liraglutide lower BMI in children aged 6 to 11?
Yes. At week 56, BMI changed by -5.8% with liraglutide and +1.6% with placebo, a difference of -7.4 percentage points (95% CI -11.6 to -3.2).
Did children on liraglutide lose weight in SCALE Kids?
On average, no. Body weight rose 1.6% with liraglutide and 10.0% with placebo. The children were still growing, so BMI fell even though weight went up slightly.
What side effects did children have on liraglutide in SCALE Kids?
Stomach and bowel side effects occurred in 80% of the liraglutide group and 54% of the placebo group. Serious side effects were reported in 12% and 8%.
Related reading
Other studies in this library that bear on the same question.
Liraglutide in adolescents with obesity
STEP TEENS: semaglutide in adolescents
Child obesity treatment and eating disorder risk review
SCALE: liraglutide 3 mg for weight management in adults
Source
Original paper: Claudia K Fox, SCALE Kids, The New England journal of medicine, 2025. PubMed: https://pubmed.ncbi.nlm.nih.gov/39258838/. DOI: https://doi.org/10.1056/NEJMoa2407379. Funding: The trial was funded by Novo Nordisk, the maker of liraglutide. How we summarized it: abstract and extracted data.
This page explains a published study. It is not medical advice and does not describe whether a medicine is right for you. Talk to your doctor, nurse practitioner or pharmacist about your own situation. Reviewed and signed by two pharmacists registered in British Columbia, 2026-09-18.
Evidence records behind this page
Each record is a row in the clinical evidence file, taken from the published paper named above. The caution column is the limit the researcher recorded for that number.
This table scrolls sideways.
| Record | What the paper reports | Type | Population | Caution | Source |
|---|---|---|---|---|---|
| R32-C106 | In SCALE Kids, children aged 6 to <12 years receiving liraglutide plus lifestyle support had mean BMI change-5.8% at 56 weeks versus+1.6% with placebo; mean body weight rose 1.6% versus 10.0%, respectively. | direct evidence | Children 6 to <12 years with obesity | Small growing-child population; reduced BMI accompanied by mean weight gain. Research evidence does not establish Canadian authorization below 12 years; no individual treatment recommendation. | PubMed 39258838 |