TZIELD: serious viral reactivation risk and new safety measures — 15 September 2026
- 15-09-2026
- Posted by: Eldaniz Hasanov
- Category: Regulatory Updates
Health Canada has published important new safety information for TZIELD (teplizumab), used to delay the onset of Stage 3 type 1 diabetes in adults and children aged 8 years and older with Stage 2 disease. Serious and life-threatening cases of viral reactivation have led to new contraindications, screening and monitoring requirements, and permanent-discontinuation criteria.
What has changed
Serious and life-threatening cases of Epstein–Barr virus (EBV) and cytomegalovirus (CMV) reactivation have been reported after treatment with TZIELD. Most reported cases occurred within two months after the last infusion. Some involved patients who continued treatment despite persistent severe lymphopenia.
TZIELD is now contraindicated in patients with an active viral infection, including EBV or CMV, any active serious infection, or an immunocompromised condition.
Advice for healthcare professionals
- Before treatment, evaluate patients for active EBV and CMV infection and confirm an undetectable viral load, alongside existing pre-treatment tests.
- Monitor for infection and viral reactivation during treatment and for at least two months after the final infusion; continue monitoring lymphocyte counts throughout treatment.
- If EBV or CMV infection is suspected, pause TZIELD and complete diagnostic testing promptly.
- Permanently discontinue TZIELD if EBV or CMV infection is confirmed, or if prolonged severe lymphopenia or any serious infection develops.
Health Canada and sanofi-aventis Canada Inc. have updated the Canadian Product Monograph to include these measures.