Tzield Accepted for Priority FDA Review

There’s good news on the horizon for people at risk for a type 1 diabetes (T1D) diagnosis, especially parents of young children. Sanofi recently announced that its drug to delay the onset of T1D, Tzield, was accepted by the Food and Drug Administration (FDA) for priority review for expanded eligibility for the treatment.

Approval would expand the eligible age for taking the medication from children 8 years and older (which was FDA-approved in late 2022) to children as young as 1 year old. The news is encouraging because FDA priority review is given to therapies that may provide great improvements in the treatment, diagnosis or prevention of serious conditions, including T1D.

This marks a second potential breakthrough for Tzield in recent months. In October, Tzield was also accepted for expedited review in the U.S. for stage 3 T1D through the FDA Commissioner’s National Priority Voucher pilot program. That approval would make Tzield the first drug to delay the progression of T1D, keeping any insulin-producing cells healthy for as long as possible after diagnosis in adults and children 8 years of age and older. 

What is Tzield?

Tzield is a medication currently approved for children 8 years and older that reduces the body’s attack on beta cells and protects the body’s ability to make insulin. This delays the onset of T1D and can prevent emergency hospital stays from diabetic ketoacidosis (DKA), as well as make diabetes easier and safer to manage in the first few years after onset.

Why is delaying the diagnosis of T1D important?

Too often, the onset of T1D comes on quickly with symptoms like excessive thirst, unexplained weight loss, frequent urination, and persistent fatigue leading to DKA, which is dangerous and can be life-threatening. However, the destruction of insulin producing cells leading up to this happens over time in three stages. Early detection and slowing the progression of diabetes can save lives. 

What are the stages of T1D?

Stage 1 T1D 

Can be detected in the blood through autoantibody testing. There are no symptoms and blood sugars are normal, but the immune system has already begun attacking the insulin-producing beta cells. The likelihood of needing to take insulin for T1D within five years is 44%, in 10 years it is 70% and lifetime risk is 100%. 

Stage 2 T1D

Can be detected in the blood through autoantibody testing. There are still no symptoms but now blood sugars have started to rise due to increased beta cell destruction. The likelihood of needing to take insulin for T1D within five years is 75% and lifetime risk is 100%. 

Stage 3 T1D

By this time, blood sugars are high and you’ll have symptoms of T1D. This includes frequent urination, excessive thirst, weight loss and fatigue. Taking insulin for T1D is now required, but the intensity is based on the level of beta cell function remaining in the body.

How does Tzield work?

Tzield can delay the progression of stage 2 diabetes to stage 3 diabetes. The delay is variable with an average delay of two years, with some experiencing a much longer delay, protecting the beta cells from damage by the immune system.

If approved for use in stage 3 diabetes, Tzield can prolong the life of the body’s remaining beta cells, increasing the amount of time a newly diagnosed person stays in the “honeymoon period”—months or years of easier and safer to manage diabetes because the body still makes small amounts of its own insulin.

Tzield is a treatment given by IV infusion. Each infusion takes about 30 minutes.

What does this mean for people at risk for diabetes?

If approved, Tzield would be the first therapy to delay the onset of T1D in children younger than 8 with stage 2 T1D. 

“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,” said Christopher Corsico, global head of development at Sanofi. 

He continues, “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.”

What happens next?

The FDA’s target action date for a decision is April 29, 2026. If approved, Tzield could be life-changing for young children already in stage 2 type 1 diabetes, helping preserve beta cell function for up to two years.

A decision on approval through the National Priority Voucher pilot program may come even sooner. If granted, it would make Tzield the first drug shown to delay the progression of type 1 diabetes after diagnosis in adults and children ages 8 and older. The FDA accepted Tzield for review under this program in October.

While preventing type 1 diabetes entirely is not yet possible, therapies like Tzield represent meaningful progress—offering more time, better outcomes, and new hope for those facing a T1D diagnosis. Until then, early detection remains critical. Learn more about the primary warning signs of type 1 diabetes and how to get screened here.