Immunogenicity and Safety of Two Doses of a Paediatric Hepatitis A Vaccine in Thai Children: Comparison of Three Vaccination Schedules

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Journal of Tropical Pediatrics

Volume 49, Issue 6, December 2003: pp. 333-339

Article

Immunogenicity and Safety of Two Doses of a Paediatric Hepatitis A Vaccine

in Thai Children: Comparison of Three Vaccination Schedules

Somsak Lolekha1, Surasak Pratuangtham1, Warunee Punpanich1, Piyaporn

Bowonkiratikachorn1, Kanittha Chimabutra1 and Françoise Weber2

1Ramathibodi Hospital, Bangkok, Thailand

2Aventis Pasteur, Lyon, France

As fewer children in Thailand are exposed to hepatitis A virus (HAV) and so

do not have seroprotective anti-HAV antibodies, they are becoming an

important source of HAV transmission. A flexible HAV vaccination schedule

would facilitate incorporation of the vaccine into existing immunization

programmes, and we compared the immunogenicity and safety of three HAV

immunization schedules. An open, randomized, clinical trial was carried out

in which healthy children were given a primary dose of the inactivated

hepatitis A vaccine, Avaxim 80 paediatric, with a booster dose 6, 12 or 18

months later. Anti-HAV geometric mean concentrations (GMC), seroconversion

rates, and GMC ratios (GMCR) of the three schedules were compared and

reactogenicity was evaluated. Seroconversion rates were above 98 per cent

(per group) up to the booster. The three schedules were equivalent in terms

of GMCRs, each eliciting a large booster effect. Local reactions were

reported for fewer than 9 per cent of each group after dose one and less

frequently after the booster dose. Injection site pain, gastrointestinal

tract disorders and fever were the most commonly reported adverse events. No

vaccine-related serious adverse events were reported. It was concluded that

the hepatitis A vaccine, Avaxim 80 paediatric, is safe and immunogenic when

given as a two-dose schedule to healthy seronegative children aged 5-10

years, with the second dose given at either 6, 12 or 18 months after the

first.

Published by Oxford University Press

Copyright ©Oxford University Press 2003

Print ISSN: 0142-6338 Online ISSN: 1465-3664.

Oxford University Press Privacy Policy and Legal Statement

[Guest guest]

Journal of Tropical Pediatrics

Volume 49, Issue 6, December 2003: pp. 333-339

Article

Immunogenicity and Safety of Two Doses of a Paediatric Hepatitis A Vaccine

in Thai Children: Comparison of Three Vaccination Schedules

Somsak Lolekha1, Surasak Pratuangtham1, Warunee Punpanich1, Piyaporn

Bowonkiratikachorn1, Kanittha Chimabutra1 and Françoise Weber2

1Ramathibodi Hospital, Bangkok, Thailand

2Aventis Pasteur, Lyon, France

As fewer children in Thailand are exposed to hepatitis A virus (HAV) and so

do not have seroprotective anti-HAV antibodies, they are becoming an

important source of HAV transmission. A flexible HAV vaccination schedule

would facilitate incorporation of the vaccine into existing immunization

programmes, and we compared the immunogenicity and safety of three HAV

immunization schedules. An open, randomized, clinical trial was carried out

in which healthy children were given a primary dose of the inactivated

hepatitis A vaccine, Avaxim 80 paediatric, with a booster dose 6, 12 or 18

months later. Anti-HAV geometric mean concentrations (GMC), seroconversion

rates, and GMC ratios (GMCR) of the three schedules were compared and

reactogenicity was evaluated. Seroconversion rates were above 98 per cent

(per group) up to the booster. The three schedules were equivalent in terms

of GMCRs, each eliciting a large booster effect. Local reactions were

reported for fewer than 9 per cent of each group after dose one and less

frequently after the booster dose. Injection site pain, gastrointestinal

tract disorders and fever were the most commonly reported adverse events. No

vaccine-related serious adverse events were reported. It was concluded that

the hepatitis A vaccine, Avaxim 80 paediatric, is safe and immunogenic when

given as a two-dose schedule to healthy seronegative children aged 5-10

years, with the second dose given at either 6, 12 or 18 months after the

first.

Published by Oxford University Press

Copyright ©Oxford University Press 2003

Print ISSN: 0142-6338 Online ISSN: 1465-3664.

Oxford University Press Privacy Policy and Legal Statement