SCALE Teens: Liraglutide in Adolescents
Last verified May 2026 · Phase 3 · Finished; headline results published March 31, 2020 · NCT02918279 ↗
Treating obesity in adolescents raises questions that do not arise in adults: growth, puberty, bone development, and the fact that a drug started at 13 may be taken for decades. Trials in this group are correspondingly cautious and small. Using BMI standard-deviation score rather than percentage weight change is the methodological adaptation that matters most, because a teenager who holds weight steady while growing has improved their BMI without losing a kilogram.
- Enrollment
- 251
- Duration
- 56 weeks of blinded treatment, then 26 weeks off the drug with a final visit at week 82
- Drug
- Liraglutide 3.0 mg (Saxenda)
- Population
- Adolescents aged 12 to 17 with obesity by the international cutoffs, who had not responded adequately to lifestyle therapy alone. ⚠ Puberty had to have started, and the exclusions were broad: type 1 or type 2 diabetes, obesity with an identifiable underlying cause, any weight drug in the previous three months, and active serious psychiatric illness. Average age about 14.5, average BMI roughly 35.3, average weight 99.3 kg, and 56 to 57% girls. Recruitment ran through Belgium, Mexico, Russia, Sweden and the US.
Primary endpoint
Change in BMI measured against other children of the same age and sex, after 56 weeks
Treatment arm
Estimated change -0.23
Comparator
Estimated change -0.00
Treatment difference: Estimated treatment difference -0.22 (95% CI -0.37 to -0.08); P=0.002
★ Why this odd-looking measure rather than pounds: adolescents are still growing. A 14-year-old who holds their weight steady for a year while gaining height has genuinely improved, and a raw weight figure would show nothing. Scoring BMI against age and sex reference charts strips out normal growth and lets a 12-year-old and a 17-year-old be compared on the same scale. The 0.22 gap cleared the pre-set bar and produced the December 2020 pediatric label.
Secondary endpoints
| Endpoint | Treatment | Comparator | Difference |
|---|---|---|---|
| Cut their BMI by at least 5% More than double the rate on lifestyle therapy alone — 43.3% against 18.7%. Pediatric guidelines treat 5% as the point where a response counts as meaningful. | 43.3% (51 of 113 evaluable) | 18.7% (20 of 105 evaluable) | Estimated odds ratio favoring liraglutide; nominal P<0.001 |
| Cut their BMI by at least 10% 26.1% against 8.1%. | 26.1% (33 of 113 evaluable) | 8.1% (9 of 105 evaluable) | Roughly 3-fold higher proportion on liraglutide |
| Change in BMI itself Down about 4.3% on the drug while creeping up slightly on placebo. | Estimated -4.29 percentage-point relative reduction | Estimated +0.35 percentage-point relative change | Estimated treatment difference -4.64 percentage points (BMI relative change) |
| Actual weight change in kilograms ★ The row that shows why the odd primary measure was necessary. The drug group lost about 2.3 kg — a modest number — while the placebo group GAINED 2.3 kg. In a growing adolescent, holding weight steady while gaining height is itself a result, and a raw weight comparison badly understates what happened. | Estimated mean change -2.26 kg | Estimated mean change +2.25 kg | Estimated treatment difference -4.50 kg favoring liraglutide |
| Weight change as a percentage About 2.7% down against 2.4% up — a five-point gap, far smaller than the newer drugs achieve. | Estimated -2.65% | Estimated +2.37% | Estimated treatment difference -5.01 percentage points favoring liraglutide |
| What happened in the 26 weeks after the drug was stopped ⛔ The most important row on this page for a family deciding whether to start. BMI rebounded further in the group that had been on the drug than in the group that had been on placebo. It did not erase the gain, and the direction was unmistakable — the same pattern every adult withdrawal trial has since found. Whatever this treatment is, it is not a course you finish. | Estimated +0.22 SDS | Estimated +0.07 SDS | Estimated treatment difference +0.15 (95% CI 0.07 to 0.23) — greater rebound in the liraglutide group after stopping |
| Blood pressure, cholesterol and blood sugar ⚠ Nothing separated the groups. Partly because adolescents start with healthier numbers and there is less to improve, and partly because 251 participants is too few to detect small differences. Absence of a signal here is not evidence of no effect. | No statistically significant between-group differences reported for systolic blood pressure, lipid panel, or HbA1c | Reference | Cardiometabolic secondary endpoints did not show separation in this 56-week pediatric cohort, in contrast to the adult SCALE Obesity and Prediabetes trial (Pi-Sunyer 2015, PMID 26132939) where blood-pressure and lipid signals emerged |
| How young people rated their own quality of life ⚠ Both groups improved, and that is the finding. Structured attention and a supportive trial environment move these scores on their own — which is a caution about any weight program advertising quality-of-life gains without a control group. | Numerical improvements reported in liraglutide group | Numerical improvements also reported in placebo group | Between-group differences were not statistically significant on prespecified quality-of-life domains |
Adverse events
| Event | Treatment rate | Comparator rate |
|---|---|---|
| Any stomach or bowel problem ⚠ Nearly two thirds of the drug group against about a third on placebo. That is a high rate in any population, and worth setting out plainly for a 13-year-old expected to attend school through it. | 64.8% (81 of 125) | 36.5% (46 of 126) |
| Nausea Around 42% against 14%, mostly mild to moderate and concentrated in the four weeks while the dose was being raised. | Approximately 42% of liraglutide arm (per supplementary AE table) | Approximately 14% of placebo arm |
| Vomiting ⚠ About 34% against 4% — the widest gap in the table, and the side effect most likely to interfere with school. It settled over time for most participants. | Approximately 34% of liraglutide arm | Approximately 4% of placebo arm |
| Diarrhea About 22% against 14%. | Approximately 22% of liraglutide arm | Approximately 14% of placebo arm |
| Stopped the drug because of a side effect 10.4% of the drug group against nobody at all on placebo, almost entirely stomach and bowel effects. | 10.4% (13 of 125) | 0% (0 of 126) |
| Serious adverse events of any kind Lower on the drug than on placebo, and below what the adult trials of the same drug reported. | 2.4% (3 of 125) | 4.0% (5 of 126) |
| Death during the trial ⛔ One participant in the drug group died by suicide. Investigators judged it unlikely to be related to treatment, and one event cannot establish or rule out a link either way. ★ Suicidal thinking is a monitored concern across every weight medication, and this trial tracked it prospectively with a validated scale rather than waiting for reports. Any adolescent starting one of these drugs should be monitored for mood, and a family should know to raise it. | 1 (suicide in liraglutide arm) | 0 |
| Low blood sugar Uncommon in both groups — anyone with diabetes was excluded from this trial. | Low and similar across arms | Low and similar across arms |
Subgroup analyses
- Younger adolescents against older ones: The same effect in both
★ This is what supported labeling the drug from 12 upward rather than restricting it to older teenagers.
- How far through puberty participants were: Consistent across every stage from early puberty to fully developed
★ A genuinely important check: puberty reshapes body composition, and it would have been reasonable to expect the drug to behave differently across it. It did not.
- Boys against girls: The drug favored in both, with overlapping uncertainty
No meaningful difference by sex.
- How high BMI was to start with: The same direction across the range, with the largest kilogram differences in the heaviest participants
The usual pattern — more starting weight means more absolute weight available to lose.
Clinical significance
This trial opened adolescent access to GLP-1 pharmacotherapy, later extended to semaglutide through STEP-TEENS. ⚠ The effect size is modest against what the newer drugs achieve in adults, and the long-term questions the trial cannot answer — what a decade of exposure during development does — remain open. It is also 251 participants over 56 weeks, which is thin evidence on which to build a lifelong treatment decision, and that is worth saying plainly to any parent reading it.
Who sells liraglutide, and for how much
This trial tested Liraglutide 3.0 mg (Saxenda). Across the 556 sellers on this register, 3 publish a standing monthly cash price for compounded liraglutide, from $160 a month, with a median of $214.
⛔ None of those sellers was in this trial. A compounded preparation is not the product studied here: no agency has reviewed that specific preparation for safety, effectiveness or manufacturing quality, and its concentration is set by whichever pharmacy filled it. The result above is the strongest evidence available for liraglutide and it was generated on something else. Every seller, with its price record.
Frequently Asked Questions
References
- 1.Kelly AS, Auerbach P, Barrientos-Perez M, Gies I, Hale PM, Marcus C, Mastrandrea LD, Prabhu N, Arslanian S; NN8022-4180 Trial Investigators A Randomized, Controlled Trial of Liraglutide for Adolescents with Obesity N Engl J Med 2020;382(22):2117-2128. 2020. PMID: 32233338.
- 2.ClinicalTrials.gov Effect of Liraglutide for Weight Management in Pubertal Adolescent Subjects With Obesity (NN8022-4180) ClinicalTrials.gov, NCT02918279. 2020. https://clinicaltrials.gov/study/NCT02918279
- 3.Weghuber D, Barrett T, Barrientos-Pérez M, et al. Once-Weekly Semaglutide in Adolescents with Obesity N Engl J Med 2022;387(24):2245-2257. 2022. PMID: 36322838.
- 4.U.S. Food and Drug Administration Saxenda (liraglutide) injection 3 mg — Prescribing Information (pediatric label expansion) DailyMed. 2020. https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=51eb02c8-3c74-4a01-bb55-13c9c9e3f74c
- 5.Hampl SE, Hassink SG, Skinner AC, et al. Clinical Practice Guideline for the Evaluation and Treatment of Children and Adolescents With Obesity Pediatrics 2023;151(2):e2022060640. 2023. PMID: 36622135.