Mounjaro was approved for adults in 2022. It took three more years to get a real answer for kids — SURPASS-PEDS is the first phase 3 trial testing tirzepatide in adolescents with type 2 diabetes.
Type 2 diabetes in adolescents tends to run a more aggressive course than the adult-onset version — beta-cell function declines faster, and first-line options like metformin or basal insulin often stop holding A1C down within a couple of years. Until recently, prescribers had few next-step options with real pediatric trial data behind them.
Mounjaro (tirzepatide) was approved for adults with type 2 diabetes in May 2022 as the first GIP/GLP-1 dual receptor agonist, but adolescent use had no dedicated trial data. SURPASS-PEDS, a regulator-required study, was designed to close that gap.
SURPASS-PEDS is a multicenter, randomized, double-blind, placebo-controlled trial with an open-label extension, presented by Eli Lilly at the European Association for the Study of Diabetes (EASD) Annual Meeting in September 2025.
All participants were inadequately controlled on metformin, basal insulin, or both going in, with an average diabetes duration of 2.4 years — a group already failing standard first-line therapy.
Tirzepatide met its primary and all key secondary endpoints. Pooled across doses, A1C fell by an average of 2.2 percentage points from baseline by week 30. In the 10 mg arm, 86.1% of participants reached a target A1C of 6.5% or lower, and BMI dropped by an average of 11.2% at the same dose. Both A1C and BMI improvements held through the 52-week open-label extension.
The side-effect pattern tracked what's already documented in adults. Diarrhea, nausea, vomiting, and abdominal pain were all more common on tirzepatide than placebo, but no severe hypoglycemia was reported in either arm — reassuring, since low blood sugar risk is a standing concern whenever a new glucose-lowering drug is tested in a pediatric population that's still growing and generally more insulin-sensitive than adults.
In the first phase 3 trial of tirzepatide in adolescents, A1C fell 2.2 points and BMI dropped 11.2% at the 10 mg dose by week 30 — improvements that held through a 52-week extension, with a side-effect profile consistent with adult studies and no severe hypoglycemia.
Sources: Eli Lilly and Company, investor press release, September 17, 2025 — "Lilly's Mounjaro (tirzepatide) reduced A1C by an average of 2.2% in adolescents". Presented at EASD Annual Meeting 2025 by lead investigator Tamara Hannon, MD (Indiana University School of Medicine). See also HCPLive coverage.
Mounjaro is not yet FDA-approved for anyone under 18. Lilly submitted the SURPASS-PEDS results to global regulators seeking an expanded pediatric indication alongside the September 2025 announcement — but that review takes time, and approval isn't guaranteed on any set timeline.
This trial is about type 2 diabetes, not weight loss. All 99 participants were enrolled for glycemic control, not primarily for obesity treatment — a separate trial, SURMOUNT-ADOLESCENTS-2, is evaluating tirzepatide for adolescent obesity specifically and hadn't reported results as of this writing.
For a family already managing an adolescent's diabetes regimen, the practical takeaway is that any pediatric use today happens under close specialist supervision, not as a routine prescription — and a tracker that logs weekly doses and side effects is exactly the kind of record a pediatric endocrinologist will want to see at follow-up visits.
This article summarizes a company-reported trial presentation and published coverage for general education. It is not medical advice and does not replace guidance from a physician. Tirzepatide is not currently FDA-approved for use in patients under 18; any pediatric use should occur only under specialist medical supervision.