FDA approves teplizumab (Tzield) for delay of type 1 diabetes progression in children 1 year and older

The FDA has approved a supplemental biologics license application for teplizumab-mzwv (Tzield; Sanofi), extending its indication to include children as young as 1 year with stage 2 type 1 diabetes (T1D). The therapy is intended to delay progression to stage 3 T1D, marking a significant expansion from its prior approval for patients 8 years and older.¹

The approval follows the FDA’s acceptance of the application for priority review, with a target action date of April 29, 2026.² Priority review designation is reserved for therapies that may offer meaningful improvements in the treatment or prevention of serious conditions, underscoring the unmet need for earlier intervention in T1D, particularly among very young children.

PETITE-T1D study supports safety and feasibility in younger children

The decision is supported by interim 1-year data from the ongoing phase 4 PETITE-T1D study (NCT05757713), which is evaluating the safety and pharmacokinetics of teplizumab in children younger than 8 years. Interim findings were presented at the 51st Annual Conference of the International Society for Pediatric and Adolescent Diabetes and published in Diabetologia.

The single-arm, nonrandomized, open-label, multicenter study has enrolled 23 participants diagnosed with stage 2 T1D. Participants receive a 14-day course of once-daily intravenous infusions, with follow-up extending up to 26 months for safety monitoring and additional assessments.

Although efficacy outcomes in this younger population have not been established, the study is designed to assess whether earlier use of teplizumab is feasible and appropriate in children with evidence of autoimmune β-cell destruction. The interim data formed the basis of the supplemental application and the FDA’s priority review decision.

Teplizumab is a CD3-directed monoclonal antibody and remains the first disease-modifying therapy approved for autoimmune T1D. It was initially authorized in 2022 to delay the onset of stage 3 disease in adults and pediatric patients 8 years and older with stage 2 T1D.

Expert perspective highlights unmet need in early-stage pediatric T1D

“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 for Diabetes in Aurora, Colorado. “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."

Understanding stage 2 type 1 diabetes and early disease progression

Type 1 diabetes is a progressive autoimmune condition characterized by immune-mediated destruction of insulin-producing pancreatic β cells. The disease progresses through presymptomatic stages marked by the presence of autoantibodies and dysglycemia before advancing to clinical hyperglycemia, at which point lifelong insulin therapy is required.

Stage 2 T1D is defined by the presence of 2 or more diabetes-related autoantibodies along with dysglycemia, prior to the onset of insulin dependence. Patients at this stage remain asymptomatic but are at high risk for progression to clinical disease. In many individuals, the autoimmune process begins in early childhood, making this a critical window for intervention.

Delaying progression to stage 3 disease may help preserve endogenous insulin production and reduce disease burden during key developmental years. Early intervention strategies targeting immune-mediated β-cell destruction are therefore an area of increasing clinical focus.

Mechanism of action underscores early immune targeting

“The autoimmune attack driving this disease often begins early in life, and the burden that autoimmune T1D poses in this very young population and their families is significant,” said Christopher Corsico, global head of development at Sanofi. “This approval underscores the importance of targeting the immune system early in autoimmune type 1 diabetes, aiming to impact its natural progression by delaying the loss of insulin production in the pancreas.”

Regulatory status and global approvals for teplizumab

Teplizumab-mzwv is currently the first and only disease-modifying therapy approved for autoimmune T1D. In the United States, it received initial approval in November 2022 for adults and pediatric patients 8 years and older with stage 2 disease.

The therapy has since been approved in multiple international markets, including China, the United Kingdom, Canada, Israel, Saudi Arabia, the United Arab Emirates, and Kuwait. In November 2025, the European Medicines Agency’s Committee for Medicinal Products for Human Use issued a positive recommendation for the same patient population, with additional regulatory reviews ongoing globally.

Teplizumab is also under FDA review for a potential indication to delay progression in patients 8 years and older who have recently been diagnosed with stage 3 T1D.

Clinical implications for pediatric screening and early intervention

For clinicians, the expanded approval introduces an earlier opportunity to intervene in the disease course of T1D. Identifying patients in stage 2—often through screening for autoantibodies—remains a key step in determining eligibility for disease-modifying therapy.

It is important to note that the safety and efficacy of teplizumab in children younger than 8 years had not previously been established by regulatory authorities, and the expanded indication is based on interim data designed to support earlier use in this population.

If adopted broadly, the expanded age indication may shift the treatment paradigm by enabling intervention at earlier stages of autoimmune disease. The availability of teplizumab for younger children may also prompt increased attention to early detection strategies and risk stratification in pediatric populations.

As the understanding of T1D pathophysiology evolves, interventions that delay progression may offer meaningful benefits, including reduced burden of care during early childhood and potential preservation of pancreatic function. Continued follow-up from ongoing studies will be important to further define long-term outcomes and optimal use of immunomodulatory therapies in this setting.

References

1. Sanofi. Sanofi’s Tzield approved in the US to delay the onset of stage 3 type 1 diabetes in young children. News release. Sanofi. 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’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 April 22, 2026.. https://www.sanofi.com/en/media-room/press-releases/2026/2026-01-05-06-00-00-3212420