17 May 2006

 

Change to the Summary of Product Characteristics for Havrix Monodose® and Havrix Junior Monodose® vaccines

GlaxoSmithKline (GSK) have recently reviewed the Summary of Product Characteristics (SPC) of their hepatitis A vaccine products in respect to their length of protection. Both Havrix Monodose® and Havrix Junior Monodose® are expected to provide protection for at least 25 years in immune competent persons following the complete two-dose primary course.

GSK have made this change based on data following a review of the persistence of anti-hepatitis A antibodies [1]. Anti-hepatitis A antibodies, considered a marker for protection against hepatitis A, have been demonstrated for up to 12 years in adults and 5 years in children following vaccination [2, 3]. Mathematical modelling of different vaccine products has consistently predicted titres to last for > 20 years [1], and some models have predicted antibody persistence up to 55 years [4].

The Joint Committee on Vaccination and Immunisation (JCVI) have previously reviewed information on inactivated hepatitis A vaccines, and have accepted a 20 year duration of protection in immune competent persons following a complete course of hepatitis A vaccine [5]. This position will be reviewed in time as more data is generated.

NaTHNaC have also examined the information and have aligned their position with that of the JCVI, accepting a 20 year duration of protection following vaccination with inactivated hepatitis A vaccines. It is likely, however, that following a primary series of hepatitis A vaccine in immune competent children and adults the duration of protection will be indefinite.

GSK have also revised their SPC on the dosing interval. It is currently recommended that two doses of a hepatitis A vaccine be given at an interval of 6 to 12 months in order to obtain long-term immunity. Evidence indicates that if the second dose is given at an extended interval there will still be a boosting immune response [6,7.8]. The SPC for GSK hepatitis A vaccine products now states that it is unnecessary to restart the primary vaccination schedule if the second dose of vaccine is administered within 5 years of the first dose.

Although booster doses delayed beyond the recommended intervals are not covered by the product licence, evidence from available studies indicates there is no interval which would require restarting a course of hepatitis A vaccine.

Further information on hepatitis A vaccine can be found on the NaTHNaC hepatitis A vaccine information sheet.

The Summary of Product Characteristics for Havrix Monodose® can be downloaded in full from the electronic Medicines Compendium website.

References

1. Van Damme P, Banatvala J, Fay O et al. Hepatitis A booster vaccination: is there a need? Lancet. 2003;362:1065-71

2. Van Herck K, Van Damme P, Lievens M et al. Hepatitis A vaccine: indirect evidence of immune memory 12 years after the primary course. J Med Virol 2004;72:194-6.

3. Fan PC, Chang MH, Lee PI, et al. Follow-up immunogenicity of an inactivated hepatitis A virus vaccine in healthy children: results after 5 years. Vaccine 1998;16:232-5.

4. Bovier PA, Bock J, Loutan L et al. Long-term immunogenicity of an inactivated virosome hepatitis A vaccine. J Med Virol. 2002;68:489-93.

5. Department of Health. Hepatitis A (Draft Chapter, November 2005). Immunisation against infectious diseases. http://www.dh.gov.uk/assetRoot/04/12/32/31/04123231.pdf  Accessed 12 May 2006.

6. Landry P, Tremblay S, Darioli R, et al. Inactivated hepatitis A vaccine booster given >/= 24 months after primary dose. Vaccine. 2001;19:399-402.

7. Beck BR, Hatz C, Bronnimann R, et al.  Successful booster antibody response up to 54 months after single primary vaccination with virosome-formulated, aluminum-free hepatitis A vaccine.  Clin Infect Dis  2003;37:126-8.

8. Iwarson S, Lindh M and Widerstrom L. Excellent booster response 4 to 8 years after a single primary dose of an inactivated hepatitis A vaccine. J Travel Med 2004;11:120-1.