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 three 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 one 

Stage one T1D can be detected in the blood with two or more islet autoantibodies. 

Islet autoantibodies are created by the immune system and are the first indication that someone may develop T1D. They show an immune response in the body. In this stage, there are no symptoms and people have normal blood sugar levels. 

Stage two 

In stage two, people will experience higher blood sugar levels due to loss of beta cells, but many people are still not experiencing symptoms at this stage. 

This is because blood sugar levels will still vary. The pancreas is still working, although not at 100 percent, and blood sugar levels are only slightly higher than normal. 

Stage three 

By this time, blood sugars are high and the classic symptoms of T1D show up. Taking insulin 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 two diabetes to stage three diabetes. The delay is variable with an average delay of 2 years, with some experiencing a much longer delay., protecting the beta cells from damage by the immune system.

If approved for use in stage three diabetes, Tzield can prolong the life of any 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 one-time treatment given daily for 14 days by IV infusion. Treatment takes about 30 minutes each day. 

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 two 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 two 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.