Weight loss drug liraglutide shows promise for younger children with obesity, study finds

Children who used the weight loss drug liraglutide in a late-stage trial lost significantly more weight than children who got a placebo, according to a new study.

Doctors say it can be extremely difficult for anyone with obesity to lose weight, no matter their age. Most adults and children 12 and older have access to highly effective new medicines called GLP-1 receptor agonists, but younger children must rely on lifestyle changes like diet, exercise and counselling alone to lose weight. Even with more aggressive interventions, children generally have only modest results, doctors say.

The first study on the effects of the GLP-1 drug liraglutide, which is sold under the brand names Saxenda and Victoza, on younger children found that the medication could have a significant impact on their body mass index (BMI), the measure that practitioners use to determine whether a person has obesity.

Liraglutide was approved by the U.S. Food and Drug Administration in 2014 to help adults lose weight. In 2020, that approval was extended to children ages 12 to 17.

The study was published Tuesday in the New England Journal of Medicine and presented at the annual European Association for the Study of Diabetes conference by its lead co-author, Dr. Claudia Fox, a pediatrician who works with the Center for Pediatric Obesity Medicine at the University of Minnesota Medical School in Minneapolis.

The researchers looked at the effects of the drug on children between the ages of 6 and 12 who had what’s considered to be a high BMI. The average 10-year-old in the study, Fox said, weighed about 155 pounds.

The trial included 82 children, of whom 56 got a liraglutide injection once a day. The rest got a placebo. All of the children also got counselling to encourage a healthier diet and exercise of moderate to high intensity for at least an hour a day.

The groups had significantly different results. In just over a year, the BMIs of the children who got the medicine fell 7.4 percentage points more than those in the placebo group. Children in the liraglutide group had a 5.8% drop in BMI. Those in the placebo group had a 1.6% increase.

The study was funded by drugmaker Novo Nordisk.

The results were in line with other studies done in teenagers, Fox said, but the younger children had stronger results.

“That to me was the most surprising, and it makes me think that maybe we should be intervening at younger ages,” Fox said.

The study does not directly compare weight loss among age groups, so more research would be needed to determine whether her theory could be correct.

Liraglutide was considered safe for the young children in the study, but participants in both the placebo group and the medication group had some adverse events.

Stomach problems like nausea, diarrhea and vomiting were more common in the group that got the medicine, but Fox said very few people dropped out of the study because of the side effects. Stomach problems tended to appear early in the study and decreased over time, she said.

The research was also not designed to address how long children would have to stay on the drugs. When the trial period was over and the children were no longer using the medication or getting counselling, their BMI crept up again. However, the increase wasn’t as significant for this younger age group as it was for teens in earlier studies, and that could mean the drugs have a more robust longer-term outcome if used earlier.

“We do know that obesity is a chronic disease,” Fox said. “As soon as the intervention is over, the disease can come back, and that is true of any other chronic disease, whether it’s diabetes, asthma, hypertension – any chronic disease that requires chronic treatment.”

Any drug that could help children with obesity could make a big impact on the public’s health. Obesity is considered the most common chronic health problem for children in the United States, with nearly 20% of all children having what’s considered a high BMI. And the number has been growing, with the prevalence more than tripling since the 1970s, according to the U.S. Centers for Disease Control and Prevention.

Obesity isn’t just a problem in the short term, as children with obesity usually become adults with obesity and can face a lifetime of health problems related to it, Dr. Simon Cork, a senior lecturer in physiology at Anglia Ruskin University, told the Science Media Centre.

“The evidence that liraglutide is both safe and effective in children is positive,” said Cork, who was not involved with the research.

Developing anti-obesity medicine for children is complicated because children are still growing, he said. More studies that monitor children for longer periods will be needed to make sure appetite suppression does not have consequences later in development. There were no indications in the new study that liraglutide was detrimental for changes in height or child’s puberty, but scientists will need to make sure that medicines don’t stunt growth.

Early puberty can be a problem for children with obesity, as can type 2 diabetes, and down the road they may develop heart problems, liver and kidney diseases and cancers. But a weight loss drug that proves to be effective in the long term could do a lot more for health than helping lose weight. Children with obesity can also face significant bias and stigma, studies show.

“Because treating children and adolescents living with obesity has the potential to have longer-lasting health benefits, although these medications are currently costly, their value for reducing risk of conditions associated with obesity and improving longer-term health must be considered,” Dr. Nerys Astbury, an associate professor of diet and obesity at the Nuffield Department of Primary Health Care Sciences at the University of Oxford, told the Science Media Centre. Astbury was not involved with the new study.

In December, draft guidelines from the U.S. Preventive Services Task Force – which influence whether insurance will cover medical care – recommended that doctors provide intensive behavioural interventions to help children lose excess weight, but it did not recommend weight loss medications or surgery.

The American Academy of Pediatrics, which updated its own guidelines on managing patients with obesity in 2023, recommended both options for some people.

Although doctors – and even parents – don’t always agree, Fox believes that weight-loss medications and surgical procedures such as gastric bypass or sleeve gastrectomy should be an option for children.

“There’s a feeling among patients’ families that they just need to work harder to lose weight, but going to the park more and eating better food isn’t always enough,” she said. “We can’t just rely only on behavioural interventions for a biological disease and get significant improvement.”