Immunogenicity & Safety Study of a Vaccine Against Meningitis in Infants (2,4,6 Months) After a Hepatitis B Birth Dose.

Study to Show Lot-to-lot Consistency of Hib-MenAC Mixed With Tritanrix™-HBV, Its Non-inferiority to Tritanrix™-HBV/Hiberix™ With or Without Meningitec™, and MenA Response in 2, 4, 6 Month Infants With Hepatitis B Birth Dose

The purpose of the study is to demonstrate consistent results in 3 production lots of Hib-MenAC vaccine when extemporaneously mixed with Tritanrix™-HepB and administered as a single injection, with respect to immunogenicity, safety and reactogenicity. Tritanrix™-HepB/Hiberix™ given alone and Wyeth Lederle's meningococcal C conjugate vaccine (Meningitec™), given concomitantly with Tritanrix™-HepB/Hiberix™ will be used as benchmark vaccines for all antigens except for MenA. The immunogenicity of MenA will also be evaluated.

Randomized study with five groups to receive one of the following vaccination regimens after a birth dose of hepatitis B vaccine: One of the 3 lots of GSK Biologicals' Hib-MenAC mixed with GSK Biologicals' Tritanrix™-HBV (3 different groups) GSK Biologicals' Tritanrix™-HBV/Hiberix™ GSK Biologicals' Tritanrix™-HBV/Hiberix™ +Meningitec™

Inclusion criteria:

• Healthy infants 56-83 days of age, written informed consent obtained from the parents, born after a gestation period of 36 to 42 weeks and received a birth dose of hepatitis B vaccine within the first 72 hours of life.

Exclusion criteria:

• Any confirmed or suspected immunosuppressive or immunodeficient condition, based on medical history & physical examination.
• Planned administration/administration of a vaccine not foreseen by the study protocol within 30 days before the first dose of study vaccine, or planned administration during the study period with the exception of oral polio vaccine (OPV).
• Use of any investigational or non-registered drug or vaccine other than the study vaccine(s) within 30 days preceding the first dose of study vaccine, or planned use during the study period.
• Chronic administration (>14 days) of immunosuppressants or other immune-modifying drugs since birth.
• Bacille Calmette-Guérin (BCG) vaccine received after the first 2 weeks of life.
• Previous vaccination against diphtheria, tetanus, pertussis, Haemophilus influenzae type b, and/or meningococcal disease.