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.
