Lilly’s Mounjaro Shows Effect in Pediatric Type 2 Diabetes Trial

Eli Lilly and Co. reports that its drug Mounjaro (tirzepatide) reduced blood sugar levels and body mass index (BMI) in children and adolescents with type 2 diabetes in a Phase 3 clinical trial, marking the first late-stage study of the therapy in this population. Type 2 diabetes in children and teenagers is increasing globally, but treatment options remain limited.

“The SURPASS-PEDS results show Mounjaro delivered statistically significant improvements in A1C, BMI, and other critical cardiometabolic risk factors, while maintaining a safety profile generally consistent with adult studies,” says Kenneth Custer, Executive Vice President, President, Lilly Cardiometabolic Health.

The company presented results from the SURPASS-PEDS trial at the European Association for the Study of Diabetes Annual Meeting and published them in The Lancet. “Youth living with type 2 diabetes often face a more aggressive disease course, and in many instances, first-line treatments like metformin and basal insulin fail to control their A1C adequately,” says Tamara Hannon, Director of the Clinical Diabetes Program, Indiana University School of Medicine. “The SURPASS-PEDS results show that Mounjaro delivered significant and clinically meaningful improvements in blood sugar, BMI, and fasting serum glucose in pediatric patients.”

The trial enrolled 99 participants aged 10 to under 18 across eight countries, including the United States, Mexico, Brazil, and the United Kingdom. At 30 weeks, patients receiving Mounjaro achieved an average A1C reduction of 2.2 percentage points from a baseline of 8.05%, compared with no meaningful change in the placebo group. Among those who received the 10 mg dose, 86% reached the target A1C of 6.5% or lower. The drug also led to reductions in BMI, with the 10mg group recording an average decrease of 11.2% at 30 weeks. Improvements in blood sugar and weight continued through the 52-week extension.

The most common adverse events in the trial were gastrointestinal, including diarrhea, nausea, and vomiting, which were mild to moderate and occurred mainly during dose escalation. Discontinuation rates due to side effects were 6% for the 5mg group, 0% for the 10mg group, and 3% for pooled doses, compared with none in the placebo group. No cases of severe hypoglycemia were reported.

Lilly has submitted the trial data to regulatory authorities seeking an expanded indication for Mounjaro in children and adolescents with type 2 diabetes. Mounjaro is already approved by the US Food and Drug Administration (FDA) for adults with type 2 diabetes and marketed as Zepbound for obesity and related conditions.

Tirzepatide, the active ingredient in both brands, is a once-weekly injectable that targets GIP and GLP-1 receptors. It reduces calorie intake, lowers fasting, and post-meal glucose and supports weight loss. Ongoing studies are evaluating its impact on chronic kidney disease and long-term outcomes in obesity.

If approved for pediatric use, Mounjaro could become one of the first new therapies available for this group in more than a decade, providing an option beyond metformin and insulin to address rising rates of youth-onset type 2 diabetes.