Lilly files the Mounjaro pediatric supplement

Eli Lilly's supplemental application for Mounjaro (tirzepatide) was received by the Food and Drug Administration on June 20, 2025, and the agency has since approved it, expanding the drug's approved use to include patients ages 10 and older with type 2 diabetes ^[1]. The filing, tracked as NDA 215866/S-039, also satisfies a postmarketing study requirement that Lilly agreed to when Mounjaro was first approved for adults in May 2022 ^[1].

The approval rests on results from trial I8F-MC-GPGV, a randomized, double-blind, placebo-controlled study in pediatric and adolescent patients with type 2 diabetes whose blood sugar was not adequately controlled on metformin, basal insulin, or both ^[1]. The study summary describes 99 participants ages 10 and older ^[1]. Under the design specified in the original 2022 postmarketing requirement, the trial ran for 30 weeks in its placebo-controlled phase, followed by a 22-week open-label extension in which all participants received tirzepatide ^[1].

The FDA's approval letter states the agency has completed its review of the application "as amended" and that it is approved effective on the date of the letter, with updated Prescribing Information and Medication Guide reflecting the pediatric data ^[1]. The agency also confirmed that the submission fulfills postmarketing requirement PMR 4271-1, the specific study obligation tied to Mounjaro's original approval letter ^[1]. Separately, the FDA noted that Lilly updated three warning sections in the label — covering acute pancreatitis, acute kidney injury from volume depletion, and severe gastrointestinal adverse reactions — to match recent labeling changes made for other GLP-1 receptor agonist drugs ^[1]. The agency also reminded Lilly that other postmarketing requirements from the 2022 approval letter and a November 2024 letter remain open ^[1].

Why it matters for patients

For families of children and teens with type 2 diabetes, this action means Mounjaro is now an FDA-approved option starting at age 10, rather than being used only in adults, as had been the case since 2022 ^[1]. Pediatric type 2 diabetes is harder to treat with existing options than the adult form, and having drug-specific safety and dosing data for this age group, generated from a controlled trial rather than off-label use, gives prescribers and parents more formal information to work with ^[1].

The label changes tied to pancreatitis, kidney injury from dehydration, and serious digestive side effects are not new to tirzepatide specifically — the FDA says these updates simply align Mounjaro's warnings with language already used for other GLP-1 medicines ^[1]. That suggests these risks are understood as a class effect across GLP-1 drugs rather than something newly discovered in the pediatric trial, though the sources do not detail what prompted the alignment or when those changes were made to competitor labels.

It is not yet known from these sources how Lilly or the FDA will communicate this pediatric approval to prescribers, when updated labeling will appear in pharmacies, or what specific dosing regimen was studied and approved for children ages 10 to 17. The approval letter also does not specify what the remaining open postmarketing requirements involve.

What happens next

Lilly must submit the finalized prescribing information and Medication Guide in a standardized electronic format within 14 days of the FDA's letter, and any pending labeling supplements must be updated to match within the same window ^[1]. Lilly is also required to submit patent information tied to the approval within 30 days ^[1]. The FDA noted that other postmarketing requirements from Mounjaro's 2022 approval and a November 2024 letter remain unresolved, meaning further regulatory filings related to Mounjaro are expected, though no specific dates for those were given in the letter ^[1].