Posology
- Dosage
The dose of 0.5 ml (360 ELISA Units HA/10 µg HBsAg) is recommended for infants, children and adolescents from 1 year up to and including 15 years of age.
- Primary vaccination schedule
The standard primary course of vaccination with Twinrix Paediatric consists of three doses, the first administered at the elected date, the second one month later and the third six months after the first dose. The recommended schedule should be adhered to. Once initiated, the primary course of vaccination should be completed with the same vaccine.
- Booster dose
In situations where a booster dose of hepatitis A and/or hepatitis B is desired, a monovalent or combined vaccine can be given. The safety and immunogenicity of Twinrix Paediatric administered as a booster dose following a three-dose primary course have not been evaluated.
Long-term antibody persistence data following vaccination with Twinrix Paediatric are available up to 15 years after vaccination (see section 5.1).
The anti-HBs and anti-HAV antibody titres observed following a primary vaccination course with the combined vaccine are in the range of what is seen following vaccination with the monovalent vaccines. General guidelines for booster vaccination can therefore be drawn from experience with the monovalent vaccines, as follows.
Hepatitis B
The need for a booster dose of hepatitis B vaccine in healthy individuals who have received a full primary vaccination course has not been established; however some official vaccination programmes currently include a recommendation for a booster dose of hepatitis B vaccine and these should be respected.
For some categories of subjects or patients exposed to HBV (e.g. haemodialysis or immunocompromised patients) a precautionary attitude should be considered to ensure a protective antibody level ≥ 10IU/l.
Hepatitis A
It is not yet fully established whether immunocompetent individuals who have responded to hepatitis A vaccination will require booster doses as protection in the absence of detectable antibodies may be ensured by immunological memory. Guidelines for boosting are based on the assumption that antibodies are required for protection.
In situations where a booster dose of both hepatitis A and hepatitis B are desired, Twinrix Paediatric can be given. Alternatively, subjects primed with Twinrix Paediatric may be administered a booster dose of either of the monovalent vaccines.
Method of administration
Twinrix Paediatric is for intramuscular injection, preferably in the deltoid region in adolescents and children or in the anterolateral thigh in infants.
Exceptionally, the vaccine may be administered subcutaneously in patients with thrombocytopenia or bleeding disorders. However, this route of administration may result in suboptimal immune response to the vaccine (see section 4.4).