Study to Asses DTPw-HBV/Hib at 15-18 Months (m) and Mencevax™ ACW at 24 to 30 m in Primed Subjects

This open study will have two parallel groups based on the vaccination received in the primary study: AC primed Group: primed with Tritanrix™-HepB/Hib-MenAC vaccine and AC unprimed Group (control): primed with Tritanrix™-HepB/Hiberix™ vaccine. All subjects will receive a booster dose of Tritanrix™-HepB/Hiberix™ vaccine at 15 to 18 months of age with GSK Biological's OPV vaccine given concomitantly and a dose of Mencevax™ ACW vaccine at 24 to 30 months of age. Blood sampling will be done prior to (pre) and one month after (post) the Mencevax™ ACW vaccine administration for immunogenicity analyses. The study will last minimum 7 to maximum 16 months per subject.

Mencevax™ ACWY was changed to Mencevax™ ACW throughout the posting to correct an inconsistency in the earlier version of the protocol posting and to reflect the actual situation.

Inclusion criteria

• 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, 15 and 18 months of age at the time of vaccination.
• 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 participated in the primary vaccination study (CPMS N° 759346/007).

Exclusion criteria

• Use of any investigational or non-registered product (drug or vaccine) other than the study vaccine within 30 days preceding the vaccination, or planned use during the study period.
• Chronic administration (defined as more than 14 days) of immunosuppressants or other immune-modifying drugs within six months prior to vaccination.
• Planned administration/ administration of a vaccine not foreseen by the study protocol within 30 days of vaccination.
• Booster vaccination against diphtheria, tetanus, pertussis, hepatitis B, Haemophilus influenzae type b (Hib) and/or meningococcal serogroups A, C or W disease, after the date of the study conclusion visit of the primary vaccination study (CPMS N° 759346/007).
• History of diphtheria, tetanus, pertussis, hepatitis B, Hib and/or meningococcal serogroup A, C or W disease.
• Known exposure to diphtheria, tetanus, pertussis, hepatitis B, Hib and/or meningococcal serogroup A, C or W disease.
• Any confirmed or suspected immunosuppressive or immunodeficient condition, based on medical history and physical examination.
• A family history of congenital or hereditary immunodeficiency.
• History of allergic disease or reactions likely to be exacerbated by any component of the vaccines administered in the study.
• Major congenital defects or serious chronic illness.
• History of any neurologic disorders or seizures including febrile seizures in infancy.
• Acute disease at the time of enrolment.
• Axillary temperature ≥ 37.5°C at the time of vaccination.
• Administration of immunoglobulins and/or any blood products within the three months preceding the vaccination or planned administration during the study period.
• Anaphylactic reaction following the administration of vaccine in the primary vaccination study.
• Known hypersensitivity to any component of the vaccine, or subjects having shown signs of hypersensitivity after previous administration of diphtheria, tetanus, pertussis, hepatitis B, Hib or meningococcal vaccines.