Novo Nordisk delivered a mixed set of developments on Monday. Positive data from a pediatric obesity trial arrived alongside fresh news that two more cardiovascular drug trials had been scrapped.

NVO was trading down 1.92%, at $46.60, as the market weighed both developments.

STEP Young Trial Results

The STEP Young phase 3 trial tested once-weekly semaglutide in 165 children aged 6 to under 12 with obesity. Semaglutide is the active ingredient in Novo's blockbuster GLP-1 medicines Wegovy and Ozempic, which are currently approved for obesity treatment in patients aged 12 and older, making this younger age group an untapped expansion opportunity. After 68 weeks, 40.4% of those who received semaglutide dropped below the obesity BMI threshold. None of the children in the placebo group reached that mark.

All participants also received lifestyle support throughout the trial, including a reduced-calorie diet and increased physical activity.

The trial met its primary endpoint, showing greater BMI reduction in the semaglutide group compared to placebo. More than 85% of participants started the trial with severe class II or III obesity. Children received either 1.7 mg or 2.4 mg of semaglutide weekly, based on their baseline weight.

Ania M. Jastreboff, Professor of Medicine and Pediatrics at Yale, said the results were encouraging given the severity of obesity seen in most participants at the start of the study.

Safety and tolerability matched what was observed in previous adult and adolescent trials. No new safety concerns were flagged, and no issues were found related to growth or pubertal development — a key consideration for therapies in children this young.

Novo plans to present full results at ObesityWeek 2026 in Washington DC, running November 14 to 17.

Ziltivekimab Setback Adds Pressure

The positive pediatric data was offset by news that Novo halted two additional trials of its experimental cardiovascular drug ziltivekimab, an anti-inflammatory drug Novo acquired through its roughly $2 billion purchase of Corvidia Therapeutics in 2020.

Both trials were studying the drug in heart failure patients and were stopped early after an independent data monitoring committee found a low likelihood either would produce results different from an earlier failed trial.

In July, ziltivekimab had already failed to reduce the risk of major adverse cardiovascular events — including death, non-fatal heart attack, and non-fatal stroke — versus placebo in a late-stage trial.

The back-to-back failures are a blow to Novo's effort to grow beyond its obesity and diabetes business, a diversification push that has taken on greater importance as rival Eli Lilly's competing GLP-1 therapies have gained ground in the obesity market.

The setback also follows a failed cardiovascular trial from Novartis, whose drug was based on the same inflammatory-disease hypothesis that underpinned development of both medicines.

What Comes Next

One remaining ziltivekimab trial, studying the drug in patients recovering from a heart attack, is still running. Results are expected in the first half of 2027.

Prescriptions for GLP-1 drugs in U.S. children under 12 have risen more than 300-fold since 2019, according to a study published Friday, even though semaglutide is not yet approved for that age group — a gap the STEP Young results could position Novo to address through regulatory filings.