FDA Accepts Supplemental Application for Teplizumab to Delay Stage 3 Type 1 Diabetes in Children Aged 1 Year and Older

The US Food and Drug Administration has accepted for Priority Review a supplemental biologic license application for Tzield (teplizumab-mzwv) to expand its age indication to include children as young as 1 year to delay the onset of stage 3 type 1 diabetes in patients diagnosed with stage 2 disease, according to an announcement from Sanofi. The agency set a target action date of April 29, 2026.¹

If approved, the expanded indication would allow use of Tzield in a younger pediatric population than its current approval, which includes adults and children aged 8 years and older with stage 2 type 1 diabetes. The Priority Review designation reflects the FDA’s assessment that the application has the potential to provide significant improvements in the prevention of a serious condition.¹

The supplemental application is supported by positive interim 1-year data from the ongoing PETITE-T1D phase 4 study (clinical study identifier NCT05757713), which is evaluating the safety and pharmacokinetics of Tzield in young children diagnosed with stage 2 type 1 diabetes. Interim findings from the study were presented at the 51st Annual Conference of the International Society for Pediatric and Adolescent Diabetes and published simultaneously in Diabetologia.²

“This priority review emphasizes the urgent need for innovative therapies like Tzield which has the potential to prevent the natural progression of T1D by delaying the loss of endogenous insulin production. This might be particularly significant in this young population, as it is well documented that the autoimmune attack that drives this disease in many cases, begins, early in life,” Christopher Corsico, Global Head of Development, Sanofi, said in a press release. “If approved, Tzield could represent an important advance for delaying the onset of stage 3 type 1 diabetes in early childhood, which would benefit patients and caregivers alike.”¹

PETITE-T1D is an ongoing phase 4, single-arm, nonrandomized, open-label, multicenter study designed to assess the safety and pharmacokinetics of Tzield in children younger than 8 years with stage 2 type 1 diabetes. Stage 2 disease is defined by the presence of two or more type 1 diabetes–related autoantibodies along with dysglycemia. The study has enrolled 23 participants who receive an intravenous infusion of Tzield once daily for 14 consecutive days, with individual follow-up and monitoring lasting up to 26 months.^1,2

Tzield is a CD3-directed monoclonal antibody that slows disease progression by protecting insulin-secreting pancreatic beta cells. It was first approved in the United States in November 2022 to delay the onset of stage 3 type 1 diabetes in adults and children aged 8 years and older with stage 2 disease. The therapy is also approved in multiple countries outside the United States for the same indication, and additional regulatory reviews are ongoing.¹

Sanofi noted that the safety and efficacy of Tzield in the PETITE-T1D study population have not been approved by any regulatory authority.¹

References:

1. Sanofi’s Tzield accepted for priority review in the US for young children with stage 2 type 1 diabetes. News release. Sanofi. January 5, 2026. Accessed January 5, 2026. https://www.news.sanofi.us/2026-01-05-Sanofis-Tzield-accepted-for-priority-review-in-the-US-for-young-children-with-stage-2-type-1-diabetes
2. Gitelman SE, Simmons K, Sherr JL, et al. Safety and pharmacokinetics of teplizumab in children less than 8 years of age with stage 2 type 1 diabetes. Diabetologia. Published online November 6, 2025. doi:10.1007/s00125-025-06586-1