Publications & Reports

Comparative immunogenicity and safety of two dosing schedules of a combined hepatitis A and B vaccine in healthy adolescent volunteers: an open, randomised study.

Burgess MA, Rodger AJ, Waite SA, Collard F
Centre for Immunisation Research, The Children's Hospital at Westmead, Cnr Hainsworth Street and Hawkesbury Road, Locked Bag 4001, NSW 2145, Westmead, Australia.


An open, randomised study was undertaken to demonstrate the equivalence in immunogenicity and to determine the reactogenicity and safety of two dosing schedules (0, 6 or 0, 12 month) of an adult formulation of a combined hepatitis A and B vaccine containing 720 EL.U. of inactivated hepatitis A antigen and 20 microg of hepatitis B surface antigen (Twinrix, SmithKline Beecham Biologicals, Belgium) in 240 healthy volunteers aged 12-15 years. The vaccine was well tolerated when administered using either vaccination schedule. At month 7, 98.1% of subjects completing the 0, 6 month vaccination schedule were seroprotected against hepatitis B (anti-hepatitis B surface antigen (anti-HBs) > or =10 mIU/ml) and 100% were seropositive for anti-hepatitis A virus (anti-HAV) antibodies (i.e., > or =33 mIU/ml). The corresponding geometric mean titres (GMTs) were 2791 mIU/ml for anti-HBs and 5992 mIU/ml for anti-HAV antibodies. At month 13, 97% of subjects assigned to the 0, 12 month vaccination schedule were protected against hepatitis B and 99% were seropositive for anti-HAV antibodies. The corresponding GMTs were 4340 and 8472 mIU/ml, respectively. A combined response (i.e., subjects, who were seropositive for anti-HAV antibodies and seroprotected for anti-HBs antibodies) was achieved in 98% of subjects vaccinated according to the 0, 6 month interval and in 96% of subjects vaccinated using the 0, 12 month schedule. The reactogenicity of both vaccination schedules was also equivalent. The results thus show that the combined hepatitis A and B vaccine can be administered using flexible vaccination intervals, which make it suitable for use in large-scale hepatitis immunisation programmes.


  • Journal: Vaccine
  • Published: 14/09/2001
  • Volume: 19
  • Issue: 32
  • Pagination: 4835-4841

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