- Expanded approval includes children aged one year and above with stage 2 T1D to delay the onset of stage 3
- Tzield is the first disease-modifying therapy for children aged one year and above diagnosed with stage 2 T1D
Paris, April 22, 2026. The US Food and Drug Administration (FDA) has approved the supplemental biologic license application for Tzield (teplizumab-mzwv), expanding the indication from eight years and older to as young as one year of age to delay the onset of stage 3 type 1 diabetes (T1D) in patients diagnosed with stage 2 T1D. The approval was granted under a priority review process and is supported by one-year data from the PETITE-T1D phase 4 study (clinical study identifier: NCT05757713), evaluating safety and pharmacokinetics in young children.
"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, Aurora, Colorado, US. “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."
"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.”
Tzield is also being reviewed by the FDA for a potential indication to delay the progression of stage 3 T1D in patients eight years of age and older recently diagnosed with stage 3 T1D.
Tzield is approved in the EU (under the name Teizeild), in the UK, China, Canada, Israel, Saudi Arabia, the UAE, Kuwait, and Brazil to delay the onset of stage 3 T1D in adults and pediatric patients eight years and older diagnosed with stage 2 T1D. Other regulatory reviews are ongoing. Tzield was previously granted FDA breakthrough therapy designation and orphan drug designation, for medicines that treat rare diseases affecting fewer than 200,000 people in the US.
About PETITE-T1D
PETITE-T1D (clinical study identifier: NCT05757713) is a phase 4 single-arm, non-randomized, open-label, multi-center study designed to assess the safety and pharmacokinetics of Tzield in children under eight years diagnosed with stage 2 T1D. Stage 2 T1D is defined by the presence of two or more T1D-related autoantibodies and abnormal blood sugar levels (dysglycemia).
The study has enrolled 23 participants. The regimen consists of an intravenous infusion of Tzield once daily for 14 consecutive days. The study duration for each individual may last up to 26 months including screening for eligibility, treatment administration and follow-up.
About autoimmune T1D
T1D is a progressive autoimmune disease where the body’s ability to regulate blood sugar levels is impacted due to the gradual destruction of insulin-producing beta cells by one’s own immune system. There are four stages to the progression of T1D:
- In stage 1, the autoimmune attack to the beta cells has started, and this can be detected by the presence of two or more T1D-related autoantibodies in the blood. During stage 1, blood sugar levels are in a normal range (normoglycemia). At this stage, T1D is presymptomatic.
- In stage 2 (also presymptomatic), in addition to the presence of two or more T1D-related autoantibodies, blood sugar levels become abnormal (dysglycemia) due to the progressive loss of beta cells / beta-cell function.
- Stage 3 (also known as clinical stage) comes once a significant portion of the beta cells have been destroyed. At this point, rising blood sugar levels reach the point of clinical hyperglycemia (which defines diabetes), and many people will start to experience the classic symptoms that come with the onset of stage 3 T1D: increased thirst, frequent urination, unexplained weight loss, blurred vision, and generalized fatigue. Management of stage 3 T1D requires daily and burdensome insulin replacement therapy.
- Stage 4 is defined as long-standing autoimmune T1D, often accompanied by evidence of chronic diabetic complications, where little to no beta-cell function remains (it has been estimated that beta-cell mass is reduced by up to 95%). At this point, the T1D-related autoantibodies might not be present anymore in the blood, as most beta cells have been rendered useless by the autoimmune attack.
About Tzield
Tzield (teplizumab-mzwv) is a CD3-directed monoclonal antibody. Tzield is the first disease modifying medicine in autoimmune T1D. It was first approved in the US in November 2022 to delay the onset of stage 3 T1D in adults and children eight years and older diagnosed with stage 2 T1D. Tzield is also approved in the EU (under the name Teizeild), the UK, China, Canada, Israel, Saudi Arabia, the UAE, Kuwait, and Brazil to delay the onset of stage 3 T1D in adults and children eight years and older diagnosed with stage 2 T1D.
What is TZIELD?
TZIELD is a prescription medicine used to delay the onset of Stage 3 type 1 diabetes, which is when your body cannot make enough insulin on its own and may require insulin injections. TZIELD is for adults and children 1 year of age and older who have Stage 2 type 1 diabetes. This means that they have tested positive for 2 or more type 1 diabetes-related autoantibodies, have abnormal blood sugar levels, and do not have type 2 diabetes or other forms of diabetes.
It is not known if TZIELD is safe and effective in children under 1 years of age.
IMPORTANT SAFETY INFORMATION
What is the most important information I should know about TZIELD?
TZIELD may cause serious side effects, including:
- Viral Reactivation. Epstein-Barr virus (EBV) and cytomegalovirus (CMV) are common viruses that may stay inactive in your body after an initial infection. TZIELD may cause these viruses to become active again which, especially in patients with a weakened immune system, can become serious and potentially life-threatening. These viral reactivations can happen during treatment with TZIELD and up to 2 months after your last dose. Your healthcare provider will test you for active EBV and CMV infections before treatment with TZIELD. Contact your healthcare provider right away if you develop symptoms of an infection during or after treatment with TZIELD (such as fever, swollen glands, or fatigue).
- Cytokine release syndrome (CRS). Signs and symptoms may start during the first 5 days of TZIELD treatment and could include fever, nausea (with or without vomiting), feeling tired (fatigue), headache, muscle and joint pain, or increased liver enzymes in your blood. Tell your healthcare provider right away if you develop any signs and symptoms of CRS during treatment with TZIELD.
- Decrease in white blood cells. TZIELD may cause a decrease in a type of white blood cell called lymphocytes. A decrease in white blood cells is a serious, but common side effect that can affect your body’s ability to fight infections. A decrease in white blood cell counts can happen after your first dose. Your white blood cell counts will start to go back to normal after your fifth dose of TZIELD. Some people may develop longer and more severe decreases in lymphocytes.
Your healthcare provider will do blood tests to check for active infections, verify your liver function and your complete blood counts before you start treatment and during treatment with TZIELD. During and after your treatment with TZIELD, your healthcare provider will check for serious side effects, as well as other side effects, and treat you as needed. Your healthcare provider may temporarily or completely stop your treatment with TZIELD, if you develop liver problems, have a serious infection or viral reactivation, or if your blood counts stay too low.
What should I tell my healthcare provider before receiving TZIELD?
Before or after receiving TZIELD, tell your healthcare provider about all your medical conditions, including if you:
• have any of the conditions or symptoms listed in the section “What is the most important information I should know about TZIELD?”
• have a weakened immune system, including if you have Down syndrome.
• have a serious infection or an infection that does not go away or keeps coming back (chronic).
• have recently received or are scheduled to receive an immunization (vaccine). TZIELD may affect how well a vaccine works. Tell your healthcare provider that you are receiving treatment with TZIELD before receiving a vaccine.
• are pregnant or plan to become pregnant. TZIELD may harm your unborn baby. Do not receive TZIELD during pregnancy and at least 30 days before a planned pregnancy.
If you become pregnant while taking TZIELD, you are encouraged to report your pregnancy to the Sanofi’s Adverse Event reporting line at 1-800-633-1610 or visit https://ae.reporting.sanofi.
• are breastfeeding or plan to breastfeed. It is not known if TZIELD passes into your breast milk and if it can harm your baby. Talk to your healthcare provider about the best way to feed your baby if you receive TZIELD.
Tell your healthcare provider about all the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements.
What are the possible side effects of TZIELD?
The most common side effects of TZIELD include:
• decrease in white blood cell counts
• vomiting
• rash
• diarrhea
• headache
These are not all of the possible side effects of TZIELD. For more information, ask your healthcare provider or pharmacist. Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088. You may also report side effects to us at 1-800-633-1610 or visit https://ae.reporting.sanofi.
Please click for full Prescribing Information, including Risk of SERIOUS SIDE EFFECTS and Medication Guide.
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