Expert Q&A: How the FDA's Expanded Teplizumab Indication Changes Type 1 Diabetes Care for Young Children

The FDA expanded the approval of teplizumab-mzwv (Tzield, Sanofi) to include children as young as 1 year with stage 2 type 1 diabetes (T1D), marking a significant advancement given that T1D is among the most common chronic childhood conditions and its incidence is rising globally, including in preschool-aged children. The expanded indication is supported by 1-year safety and pharmacokinetics data from the PETITE-T1D phase 4 study, which showed a safety profile in children younger than 8 years consistent with that seen in older patients, with vomiting and diarrhea as the most common adverse reactions in the younger cohort.

To address safety risks, Sanofi updated teplizumab's label—now including a boxed warning—with clear guidance on Epstein-Barr virus (EBV) and cytomegalovirus (CMV) testing prior to treatment, monitoring during and after infusion, and criteria for pausing or stopping therapy. Pharmacists are positioned to play a pivotal role in this new landscape by supporting families with adherence, ensuring pretreatment protocols are followed, and helping caregivers manage adverse effects such as nausea, which younger children may struggle to communicate verbally.

Mattias Wieloch, vice president and North America medical head of autoimmune type 1 diabetes at Sanofi, discusses the FDA's expanded approval of teplizumab for children as young as 1 year with stage 2 T1D, covering PETITE-T1D safety findings, updated EBV/CMV label guidance, and the critical role pharmacists play in supporting young patients and their families.

Pharmacy Times: Why is expanding teplizumab’s indication to include children as young as 1 year a critical milestone for T1D management?

Mattias Wieloch: T1D is one of the most common chronic childhood conditions, and its incidence is rising worldwide, including among preschool-aged children. We believe that this approval opens an important new chapter in diabetes care for young children with stage 2 T1D and their families. The opportunity to delay the onset of stage 3 T1D in this younger age group may be particularly significant, as the autoimmune attack responsible for T1D often begins early in life.

Pharmacy Times: What were the primary safety and efficacy takeaways from the PETITE-T1D study that supported this younger age indication?

Wieloch: The approval was granted under the FDA's priority review pathway and is supported by 1-year data from the PETITE-T1D phase 4 study, evaluating the safety and pharmacokinetics of teplizumab in young children. The efficacy of teplizumab that led to approval in stage 2 was studied in the TN-10 study [NCT04270942] in [individuals] 8 years and above. PETITE did not evaluate efficacy. Overall, the safety profile of teplizumab observed in pediatric patients younger than 8 years with stage 2 T1D was consistent with that observed in patients 8 years and older with stage 2 T1D. The most common adverse reactions that occurred in patients less than 8 years of age were vomiting and diarrhea. The study findings were published in Diabetologia and can be found here.

Pharmacy Times: How should health care teams manage the risk of cytokine release syndrome and viral reactivation (EBV/CMV) in this younger population?

Wieloch: Patient safety is our top priority. In collaboration with the FDA and based on continuous pharmacovigilance assessment, Sanofi updated teplizumab’s label, with a boxed warning reinforcing EBV and CVM testing, monitoring, and management. We welcome this update, and we are ready to support HCPs [health care providers] with any questions they might have about this. The update will create awareness and give clear guidance to test before starting teplizumab treatment to make sure the person doesn’t have active EBV/CMV. The language also provides guidance on who is at risk for EBV/CMV reactivation and to monitor those individuals during and after teplizumab treatment. Additionally, the update provides clear guidance on when to pause and stop teplizumab treatment.

Pharmacy Times: How can pharmacists best assist families in navigating the transition from a stage 2 diagnosis to starting this disease-modifying therapy?

Wieloch: We understand that patients, their families, and their health care professionals may have questions. Our understanding of the T1D continuum has evolved over the past few years. Pharmacists will continue to play a pivotal role in ensuring access and adherence at all stages. As an example, it is important to stay hydrated before and throughout the infusion. While nausea can sometimes occur during treatment, young children can have a hard time explaining that they are nauseous, which can lead to vomiting. Ensuring that recommended pretreatments are explained and followed to reduce any potential [adverse] effects of teplizumab treatment will be important.