FDA Expands Teplizumab Approval to Children 1 Year & Older to Delay Type 1 Diabetes Onset

The US Food and Drug Administration (FDA) has expanded the indication for teplizumab-mzwv (Tzield) to include children as young as 1 year of age with stage 2 type 1 diabetes (T1D), allowing use to delay progression to clinical (stage 3) disease.1

The decision, announced by Sanofi on April 22, 2026, extends prior approval for patients aged 8 years and older and marks the first disease-modifying therapy available for very young children at high risk of developing symptomatic T1D. The expanded indication is supported by safety and pharmacokinetic data from the phase 4 PETITE-T1D study.1,2

"This approval opens an important new chapter in diabetes care for young children with stage 2 type 1 diabetes and their families,” said Kimber Simmons, MD, MS, associate professor of pediatrics at the Barbara Davis Center, in a press release. “This is especially important because these children are often at the highest risk of progressing quickly and without warning. Delaying the onset of stage 3 type 1 diabetes during the years when management is often most difficult because of a child’s small size and dependence on caregivers could have a truly meaningful impact for families."

FDA Expands Tzield Indication to Younger Children With Stage 2 Type 1 Diabetes

Teplizumab is a CD3-directed monoclonal antibody designed to modulate the autoimmune process underlying T1D. It was initially approved in 2022 to delay progression to stage 3 disease in adults and pediatric patients aged 8 years and older with stage 2 T1D.1

The updated approval now includes children aged 1 year and older with stage 2 disease, defined by the presence of 2 or more T1D-associated autoantibodies and dysglycemia. This stage precedes symptomatic diabetes but reflects ongoing autoimmune-mediated beta-cell destruction.1,2

The FDA granted the expanded indication under priority review, reflecting the unmet need for interventions that can alter disease progression in early T1D.1,2

PETITE-T1D Study & Teplizumab

The expanded approval is based on data from PETITE-T1D, a phase 4, open-label, single-arm, multicenter study evaluating teplizumab in children younger than 8 years with stage 2 T1D.1

The study enrolled 23 participants who received a 14-day course of intravenous teplizumab. The trial was designed primarily to assess safety and pharmacokinetics rather than efficacy outcomes.1

Although limited by its small size and nonrandomized design, the study provided supportive evidence that the safety profile of teplizumab in younger children is consistent with that observed in older populations.¹

The approval reinforces a shift toward earlier intervention in T1D, focusing on modifying disease course before the onset of clinical symptoms. At the time of the April 22, 2026 announcement, teplizumab remains the only FDA-approved therapy with this disease-modifying intent in T1D.1

Regulatory review is ongoing for an additional indication evaluating whether teplizumab may delay progression in patients with newly diagnosed stage 3 T1D aged 8 years and older.1

Teplizumab has also received regulatory approvals in multiple regions outside the US, including the European Union, United Kingdom, and Canada, for delaying progression to stage 3 T1D in patients aged 8 years and older with stage 2 disease.1

References:

1. Sanofi. Press Release: Sanofi’s Tzield approved in the US to delay the onset of stage 3 type 1 diabetes in young children. Sanofi.com. Published April 22, 2026. Accessed April 22, 2026. https://www.sanofi.com/en/media-room/press-releases/2026/2026-04-22-05-05-00-3278650

2. Sanofi. TZIELDTM (teplizumab-mzwv) approved by FDA as the first and only treatment indicated to delay the onset of Stage 3 type 1 diabetes (T1D) in adult and pediatric patients aged 8 years and older with Stage 2 T1D - Nov 17, 2022. Sanofi.us. Published November 17, 2022. Accessed April 22, 2026. https://www.news.sanofi.us/2022-11-17-TZIELD-TM-teplizumab-mzwv-approved-by-FDA-as-the-first-and-only-treatment-indicated-to-delay-the-onset-of-Stage-3-type-1-diabetes-T1D-in-adult-and-pediatric-patients-aged-8-years-and-older-with-Stage-2-T1D