Teplizumab at a glance
Medicine class
CD3-directed humanised monoclonal antibody
Licensed role
Delays Stage 3 type 1 diabetes in eligible people with confirmed Stage 2 disease
Administration
Given as a diluted intravenous infusion by a healthcare professional
Key checks
Blood counts, liver tests, infections and vaccination history are assessed before treatment
What is Teplizumab used for?
Teplizumab is licensed for:
Delaying the onset of Stage 3 type 1 diabetes in adults and children aged 8 years and older with confirmed Stage 2 type 1 diabetes.
How does Teplizumab work?
Teplizumab binds CD3 on T lymphocytes. Its effects are thought to reduce the activity of T cells that attack pancreatic beta cells while increasing regulatory and functionally exhausted T-cell populations, helping preserve insulin production for longer.
Teplizumab preparations and strengths
Solution for infusion
Route: Intravenous
Strengths: 2 mg/2 mL
How to take Teplizumab
Teplizumab is prepared and given through a vein by a healthcare professional. The concentrate must be diluted before use. Other medicines must not be added to it or infused simultaneously through the same intravenous line.
Medicines for fever or pain, an antihistamine and sometimes an anti-sickness medicine may be given beforehand to reduce infusion-related symptoms.
Blood tests and clinical monitoring are required during treatment.
Tell the team promptly if you feel unwell or develop infection symptoms.
Teplizumab side effects
Common or expected effects
- Reduced lymphocyte, white-cell, neutrophil, red-cell or platelet counts
- Rash or itching
- Headache
- Nausea
- Fever
- Raised liver enzymes
- Reduced blood bicarbonate or calcium
- Diarrhoea, chills, hives, or nose and throat inflammation
Get urgent medical advice
- Cytokine release syndrome, which may cause fever, fatigue, headache, nausea, muscle or joint pain, and abnormal liver tests
- Severe allergic reactions, including facial or throat swelling, bronchospasm, or collapse
- Serious bacterial or viral infection
- Severe or persistent reduction in lymphocytes
- Clinically important liver-test abnormalities
Teplizumab in pregnancy
Experience during pregnancy is insufficient, and placental transfer could suppress the unborn baby's immune system. The UK product information advises avoiding teplizumab during pregnancy and for at least 30 days before a planned pregnancy. Discuss pregnancy plans promptly with the specialist team.
Teplizumab while breastfeeding
It is unknown whether teplizumab enters human milk or affects a breastfed child. The UK product information describes interrupting breastfeeding and expressing and discarding milk during treatment and for 20 days afterwards to minimise exposure. Discuss feeding options with the specialist team.
Teplizumab interactions
Formal interaction studies have not been performed. Important practical considerations include:
Live vaccines
Teplizumab may reduce vaccine responses; live vaccines are not recommended close to treatment or for the specified post-treatment period.
Inactivated or mRNA vaccines
These should be completed before treatment where possible and avoided during the periods specified in the product information.
Immunosuppressive medicines
Combined safety and effectiveness have not been established, so concomitant use requires caution and specialist review.
Common questions about Teplizumab
Answers are fully visible for fast scanning and source review.
Is teplizumab licensed in the United Kingdom?
Yes. The MHRA authorised it on 14 August 2025 to delay Stage 3 type 1 diabetes in eligible adults and children aged 8 years and older with Stage 2 disease.
Who may be eligible for teplizumab?
People aged 8 years or older with confirmed Stage 2 type 1 diabetes may be considered after specialist assessment and safety checks.
Does teplizumab cure type 1 diabetes?
Sources
These sources were used to prepare and review this medicine page.
Prepared and reviewed by the iatroX editorial team.