Tzield (Teplizumab) to Delay Type 1 Diabetes
Tzield has been shown to delay the onset of type 1 diabetes by an average of two years. Here’s more about screening and whether treatment may be right for you.
Finding a cure for type 1 diabetes has been a priority in diabetes research for decades. Tzield (teplizumab), which was first approved by the FDA in 2022, has brought us one step closer by providing a way to delay the onset of type 1 diabetes. The medication marks an impressive milestone in diabetes research.
Tzield is the first and only treatment to delay the onset of stage 3 type 1 diabetes in adults and children aged 1 year and older with stage 2 type 1 diabetes. Previously, the treatment was only available to children ages 8 and older, but as of April 2026, the FDA expanded the approval to include children as young as 1. The move makes type 1 diabetes screening more actionable for families with young children, who now have time to learn about insulin dosing, managing glucose, meal planning, and overnight monitoring. Delaying stage 3 for a period of time can reduce stress and worry and provide a meaningful time to adjust as a family.
“It cannot be emphasized enough how precious a delay in the onset of stage 3 type 1 diabetes can be from a patient and family perspective. More time to live without and, when necessary, prepare for the burdens, complications, and risks associated with stage 3 disease,” said Ashleigh Palmer, who played a major role in the development of Tzield before the drug was acquired by Sanofi.
Tzield is an injectable drug taken once daily for 14 days. It works by binding to and modifying cells in the immune system called T-cells. In people with type 1 diabetes, T-cells destroy the insulin-producing beta cells in the pancreas. With the help of Tzield, this self-destructive process is interrupted, effectively delaying the onset of type 1 diabetes by an average of about two years.
Who is eligible to receive Tzield?
There are three stages of type 1 diabetes:
- Stage 1: Blood sugar levels are normal and the person experiences no symptoms, but has two or more autoantibodies associated with type 1 diabetes. People who test positive for at least two autoantibodies are almost certain to progress to stage 3 at some point in their lives.
- Stage 2: There are no symptoms of type 1 diabetes, but blood sugar levels are abnormal and autoantibodies for type 1 are present.
- Stage 3: Blood sugar levels are high and symptoms are commonly present (frequent urination, dry mouth, fatigue, and diabetic ketoacidosis). In the past, a person would not receive a clinical diagnosis of type 1 diabetes until they progressed to stage 3.
Currently, Tzield is approved for people aged 1 and older diagnosed with stage 2 type 1 diabetes, meaning they have abnormal blood sugar levels. A person can be diagnosed with type 1 diabetes before developing apparent symptoms by undergoing a screening test that confirms the presence of at least two specific autoantibodies. A positive test indicates that the body is already attacking the insulin-producing beta cells in the pancreas.
How to get tested for type 1 diabetes autoantibodies
Screening for type 1 diabetes autoantibodies is extremely important for early detection and timely treatment. Here are three ways to get screened:
- Autoimmunity Screening for Kids: All children and adults in the U.S. are eligible to receive a free blood test for type 1 diabetes and celiac disease through the Barbara Davis Center for Diabetes at the University of Colorado. People who live more than 30 miles away from the screening sites in Colorado can request an at-home blood test that can be submitted to Labcorp for analysis.
- TrialNet: This is a clinical trial program that provides free testing to those who have a relative who has been diagnosed with type 1 diabetes.
- Doctor’s office or lab: A doctor can order a blood test that may be done in the clinic or a lab, such as LabCorp or Quest Diagnostics.
People who test positive for two or more autoantibodies will need to discuss results and develop a plan moving forward with their healthcare providers. Sanofi also has a resource guide about how to get screened.
Potential risks
There are benefits to delaying type 1 diabetes with Tzield, but there are also risks to taking it or any drug. The most common side effects include rash, headache, and decreased levels of white blood cells. In particular, Tzield may reduce your lymphocytes, which fight infections.
Most people who experience decreases in their white blood cell count will get back to their normal numbers within two weeks of finishing treatment. Still, a drop in white blood cells increases a person’s risk for developing a serious infection during treatment. Therefore, anyone who receives Tzield must have completed all age-appropriate vaccines well ahead of beginning treatment. Furthermore, people currently undergoing Tzield therapy should immediately tell their healthcare provider if they notice signs of illness.
More rarely, Tzield can cause cytokine release syndrome, which is when the immune system responds too aggressively to an infection or immunotherapy drugs. Symptoms of this potentially serious condition include fever, muscle and joint pain, fatigue, and nausea.
Finally, Tzield can cause hypersensitivity reactions, including difficulty breathing, swelling of the face, rash, and hives. If you think you are experiencing either cytokine release syndrome or a hypersensitivity reaction, you should seek immediate medical attention.
How to access Tzield
Once a healthcare provider confirms eligibility for Tzield, the next step is filling out an enrollment form and sending it to Sanofi.
One of the company’s patient navigators from their COMPASS program will then reach out. The patient navigator will be the person’s guide and main point of contact through the rest of the process.
Tzield cost
As of January 2026, the wholesale cost per vial of Tzield is around $14,411, which translates to $201,753 for a 14-day continuous regimen. Some people may require additional vials on days five through 14 of the treatment, depending on their body surface area and weight.
Most insurance programs in the U.S. provide some coverage for Tzield, but copays will vary from plan to plan. Some people with commercial insurance plans may be eligible for the Tzield Copay Program, which could help them receive treatment for free or low cost. Sanofi also offers patient assistance programs for those without insurance or whose insurance plans do not cover Tzield.
The COMPASS program's patient navigators can help with any insurance questions and financial assistance. Even before enrolling, patients and healthcare providers can learn more by calling COMPASS at 844-778-2246 or visiting the Tzield website.
What’s next?
Positive results from an ongoing clinical trial have shown that Tzield may also be beneficial for children and adolescents who have recently progressed to stage 3 type 1 diabetes, prompting the FDA to expedite its review of Tzield for stage 3. However, following a patient’s death, the FDA is delaying its review to investigate whether the death was related to treatment or not. Other adverse events have also been reported, including blood clots and seizures. As a result, the FDA will likely need more time prior to determining the expanded approval or not.
Learn more about Tzield, type 1 diabetes delay or prevention, and screening here: