Novo Nordisk Reports Positive Results from Phase 3 Clinical Trial of Semaglutide in Children with Obesity

Novo Nordisk announced positive results from a phase 3 clinical trial of semaglutide in children aged 6 to 12 who are living with obesity. The STEP Young trial, which met its primary endpoint, demonstrated that semaglutide, in combination with lifestyle modifications, significantly reduced body mass index (BMI) in children with obesity.

The trial involved 165 children with obesity, classified as having severe obesity at baseline, with a BMI above the 95th percentile. After 68 weeks of treatment, 40.4% of the children in the semaglutide group no longer met the criteria for obesity based on CDC growth charts, compared to none in the placebo group. This means that semaglutide helped reduce the BMI to a normal or overweight category for two out of five children, an improvement not seen in the placebo group.

"Childhood obesity is particularly concerning due to both immediate and enduring impacts on health, including a strong predilection to adult obesity and increased risk for the early emergence of obesity-related complications," said Ania M. Jastreboff, MD, PhD, Professor of Medicine (Endocrinology) and Pediatrics (Pediatric Endocrinology) at Yale and Director of the Yale Obesity Research Center (Y-Weight).

Children living with obesity often experience cardiovascular disease risk factors, alongside depression, eating disorders, and bullying, with studies showing that their quality of life is comparable to children undergoing cancer treatment. Without effective intervention, childhood obesity strongly tracks into adulthood, where obesity-related complications emerge earlier and more severely, substantially shortening life expectancy.

"Childhood obesity can begin early and affect wellbeing throughout life," said Martin Holst Lange, executive vice president, chief scientific officer, and head of Research & Development at Novo Nordisk. "As a pioneer in pediatric obesity medicine, we are encouraged by the positive STEP Young results and semaglutide's potential to help children living with obesity who need medical treatment, alongside lifestyle changes, to better manage their obesity."

The overall safety and tolerability of semaglutide were consistent with those seen in adults and adolescents. No new safety concerns were identified, and there were no concerns for growth or pubertal development. Detailed STEP Young results will be presented at The Obesity Society's annual meeting, ObesityWeek 2026, in Washington, DC.

The STEP Young trial is part of the ongoing clinical development program for semaglutide, following the positive phase 3 results in adults and adolescents with obesity. Semaglutide is a glucagon-like peptide-1 (GLP-1) receptor agonist that mimics the effects of the naturally occurring hormone GLP-1, which regulates blood sugar and body weight.

Novo Nordisk, a leading global healthcare company founded in 1923, continues to drive change to defeat serious chronic diseases, including obesity. With a strong focus on scientific breakthroughs and expanding access to medicines, Novo Nordisk aims to prevent and ultimately cure diseases.