Study of Long-term Antibody Persistence After a Booster Dose of Menitorix Vaccine

The purpose of this study is to evaluate the long-term antibody persistence at 12, 24 and 48 months after the administration of a booster dose of Menitorix™, given at 12-15 months of age. The children had previously received 3 doses of Menitorix™ and Infanrix IPV™ or Meningitec™ and Pediacel™ in infancy. In addition, the antibody persistence is to be investigated in children of 40-43 months of age who received a 3-dose primary vaccination of a MenC conjugate vaccine and a Hib containing vaccine in infancy without a booster dose of MenC conjugate and Hib vaccine in the second year of life.

This protocol posting deals with objectives \& outcome measures of the extension phases at 12, 24 and 48 months after the booster phase. The links to objectives and outcome measures of the primary phase \& booster phase at 12 to 15 months are provided below:

https://www.gsk-studyregister.com/study/2747 (Primary phase) https://www.gsk-studyregister.com/study/2755 (Booster phase)

This multicentre \& multicountry study is open and has 2 study groups at Visits 1 and 3 (HibMenC and LicMenC). An additional control group in the UK at the time of the second year follow-up for persistence (subjects aged 40-43 months primed with MenC conjugate and Hib vaccines in infancy with no subsequent booster dose, group NoBoost at Visit 2). These subjects will receive a Hib catch-up vaccine at 40-43 months of age. The subjects of groups HibMenC and LicMenC were randomized in the primary vaccination study 103974 and will not be further randomized. The subjects of group NoBoost will not be randomized. All subjects at the UK centre will receive Infanrix™-IPV at the second visit (i.e. 24 months after Menitorix booster or at 40-43 months of age). In addition, the subjects of group NoBoost will receive a Hib catch-up vaccine (Menitorix™) at the same visit.

Subjects of groups HibMenC and LicMenC will have 3 blood samples taken for immunogenicity analyses: at 12, 24 \& 48 months after the booster vaccination. Subjects of group NoBoost will have 1 blood sample taken for immunogenicity analyses at 40-43 months of age. 75 new subjects will be enrolled in this study (group NoBoost).

Eligibility Criteria:
Inclusion Criteria:

Subjects of groups HibMenC and LicMenC at Visits 1, 2 and 3:

* Subjects who the investigator believes that their parents/guardians can and will comply with the requirements of the protocol.
* A male or female between and including 24 and 31 months of age at the time of Visit 1, between and including 40 and 43 months of age at Visit 2 and between and including 60 and 64 months at Visit 3.
* Written informed consent obtained from the parent or guardian of the subject.
* Healthy subjects as established by medical history and clinical examination before entering into the study.
* Having completed the booster vaccination study 104056.

Subjects of group NoBoost at Visit 2 (UK only):

* Subjects who the investigator believes that their parents/guardians can and will comply with the requirements of the protocol.
* A male or female between and including 40 and 43 months of age at Visit 2.
* Written informed consent obtained from the parent or guardian of the subject.
* Healthy subjects as established by medical history and clinical examination before entering into the study.
* Having received a 3-dose primary vaccination with a MenC conjugate vaccine and a Hib containing vaccine before the age of 8 months.

Exclusion Criteria:

* Previous administration of booster dose of Hib or meningococcal serogroup C except booster study vaccines during the study 104056.
* History of H. influenzae type b or meningococcal diseases.
* For UK subjects of groups HibMenC and LicMenC only: previous administration of a booster dose of a pertussis-containing vaccine except booster study vaccines during the study 104056.