FDA Grants Priority Review to Tzield for Early Childhood Type 1 Diabetes

The US FDA has moved fast. It has accepted a priority review for Sanofi’s supplemental biologics license application (sBLA) for Tzield (teplizumab-mzwv). The goal: expand use to children as young as one year old.

If approved, Tzield could delay the onset of stage 3 type 1 diabetes (T1D) in very young patients diagnosed with stage 2 T1D.

The FDA’s target decision date is April 29, 2026.

What Changed in the Label Request?

Currently, Tzield is approved for:

• Adults and children 8 years and older
• Patients diagnosed with stage 2 T1D

The new sBLA seeks approval for:

• Children aged 1 year and above
• The same disease stage and indication

This would push disease-modifying treatment years earlier than ever before.

Data Behind the Priority Review

The application is backed by positive interim one-year data from the PETITE-T1D phase 4 study (NCT05757713).

Key study details:

• Phase 4, single-arm, open-label, multicentre
• Children under 8 years with stage 2 T1D
• Primary focus: safety and pharmacokinetics

The interim results were:

• Presented at the 51st ISPAD Annual Conference
• Published simultaneously in Diabetologia

Why the FDA Fast-Tracked This Review?

Priority review is reserved for therapies that may:

• Significantly improve treatment
• Prevent serious diseases
• Address urgent unmet medical needs

According to Sanofi, the case is clear. Autoimmune destruction in T1D often begins early in life. Delaying beta-cell loss at this stage could change lifelong outcomes.

What Tzield Actually Does?

Tzield is:

• A CD3-directed monoclonal antibody
• The first and only disease-modifying therapy in autoimmune T1D

Instead of treating symptoms, it:

• Modulates the immune response
• Slows destruction of insulin-producing beta cells
• Delays progression to clinical diabetes

That distinction matters.

Inside the PETITE-T1D Study

Study design highlights:

• 23 enrolled children
• Diagnosed with stage 2 T1D
• Defined by:
  • Two or more T1D-related autoantibodies
  • Abnormal blood sugar (dysglycaemia)

Treatment regimen:

• 14 daily intravenous infusions
• Follow-up lasting up to 26 months

Regulatory approval for this population is not yet granted.

Understanding the Stages of Type 1 Diabetes

T1D progresses through four stages:

Stage 1

• Autoantibodies present
• Normal blood sugar
• No symptoms

Stage 2

• Autoantibodies plus dysglycaemia
• Still presymptomatic
• Progressive beta-cell loss begins

Stage 3

• Clinical diabetes
• Hyperglycaemia and symptoms appear
• Daily insulin therapy required

Stage 4

• Long-standing disease
• Up to 95% beta-cell loss
• Chronic complications common

Tzield targets the disease before stage 3 begins.

Global Regulatory Status

Tzield was first approved in the US in November 2022.

It is now approved in:

• China
• UK
• Canada
• Israel
• Saudi Arabia
• UAE
• Kuwait

In November 2025, the EMA issued a positive CHMP opinion. In Europe, the drug will be marketed as Teizeild. Other regulatory reviews are ongoing.

The Bigger Picture

This sBLA is not incremental. It signals a shift toward:

• Earlier intervention
• Immune-based disease modification
• Pre-symptomatic treatment strategies

If approved, Tzield could redefine how early type 1 diabetes is treated—and how early it can be delayed.