STEP TEENS extends semaglutide evidence to adolescents
A 68-week trial in 201 teens with obesity found BMI dropped 16.1% on weekly 2.4 mg semaglutide versus a 0.6% rise on placebo, with more gastrointestinal side effects and gallstones. [1]
Researchers reported that once-weekly semaglutide at 2.4 mg — the dose sold for weight management as Wegovy — cut body-mass index by an average of 16.1% over 68 weeks in adolescents with obesity, compared with a 0.6% increase in a placebo group. [1] The results come from STEP TEENS, a Novo Nordisk–funded randomized trial published in the New England Journal of Medicine. [1]
The trial enrolled 201 people aged 12 to under 18 who had obesity (BMI at or above the 95th percentile) or who were overweight (BMI at or above the 85th percentile) plus at least one weight-related health condition. [1] All but one participant had obesity. [1] Participants were assigned in a 2-to-1 ratio to weekly injections of semaglutide or placebo for 68 weeks, and both groups also received a lifestyle intervention. [1] Of the 201 randomized, 180 (90%) completed treatment. [1]
What the numbers showed
The main measure was the percentage change in BMI from the start of the study to week 68. The estimated difference between groups was 16.7 percentage points in favor of semaglutide (95% confidence interval, −20.3 to −13.2; P<0.001). [1]
The study's second key measure was the share of participants who lost at least 5% of their body weight. At week 68, 95 of 131 participants (73%) taking semaglutide hit that mark, compared with 11 of 62 (18%) on placebo — an estimated odds ratio of 14.0 (95% CI, 6.3 to 31.0; P<0.001). [1] The published figures also break out the proportions who lost at least 10%, 15% and 20%, though those specific percentages are not given in the abstract. [1]
Beyond weight, the semaglutide group had greater improvements in waist circumference, glycated hemoglobin (a measure of blood sugar), lipids other than HDL cholesterol, and alanine aminotransferase, a liver enzyme. [1]
Side effects
Stomach and bowel side effects were more common with semaglutide than placebo: 62% versus 42%. [1] Five participants (4%) in the semaglutide group developed gallstones (cholelithiasis), compared with none in the placebo group. [1] Serious adverse events were reported in 15 of 133 participants (11%) taking semaglutide and 6 of 67 (9%) taking placebo. [1]
The trial design included a follow-up period after participants stopped taking semaglutide or placebo, but the abstract does not report what happened to weight during that off-treatment stretch. [1]
Why it matters for patients
Until this trial, the 2.4 mg weekly dose of semaglutide had been tested mainly in adults, and the authors noted that evaluation of the drug in adolescents "has been lacking." [1] STEP TEENS is the randomized evidence that regulators and pediatric clinicians had been missing for this age group.
For families weighing options, a few details matter. The comparison here was semaglutide plus lifestyle intervention versus lifestyle intervention alone — not against another medication or surgery. [1] The study measured BMI change as its primary result, which is the standard approach in pediatric obesity research because teens are still growing, while the 5% weight-loss threshold gives a more familiar benchmark. [1]
The safety picture is also part of the trade-off. Roughly three in five teens on semaglutide had gastrointestinal side effects, and a small number developed gallstones, an issue that has also been seen with rapid weight loss generally. [1] Serious adverse events occurred at similar rates in both groups. [1]
What the trial does not answer is how long treatment would need to continue, what happens to weight and growth over several years, or how these results apply to children younger than 12. Those questions are not addressed in the published abstract. [1]
What happens next
The study appeared in the New England Journal of Medicine on Nov. 2, 2022 (trial registration NCT04102189). [1] Letters debating the findings, along with a reply from the investigators, were published in the same journal on March 23, 2023. [1]
The timing of any US regulatory action on a pediatric indication for Wegovy is not described in the source material available here, so that detail is not confirmed by this trial report. [1]
Sources
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