The primary purpose of this study is to demonstrate the lot-to-lot consistency of 3 production lots of GSK Biologicals' Hib-MenAC (Haemophilus influenzae type b and meningococcal serogroups A and C) vaccine when reconstituted with Tritanrix™-HepB (diphtheria, tetanus, pertussis, and hepatitis B) vaccine and administered as a single injection.

The study is double blind. However the active control vaccine Tritanrix™-HepB/Hiberix™ will be administered in a single-blind manner. Blood samples will be collected for immunogenicity analyses. GSK Biologicals' OPV vaccine will be administered concomitantly with the study vaccines at 2, 4 and 6 months of age according to local country regulation. The study will last approximately 5 months per subject

Inclusion criteria:

• healthy male or female, between, and including, 56 and 83 days of age.
• Born after a gestation period between 36 and 42 weeks
• Birth dose of hepatitis B vaccine within the first 72 hours of life

Exclusion criteria:

• 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.
• Bacille Calmette-Guérin (BCG) vaccine received after the first 2 weeks of life.
• History of OR previous vaccination against OR known exposure since birth to diphtheria, tetanus, pertussis, hepatitis B, Haemophilus influenzae type b and/or meningococcal disease.
• Any confirmed or suspected immunosuppressive or immunodeficient condition, including human immunodeficiency virus (HIV) infection
• A family history of congenital or hereditary immunodeficiency
• History of any neurologic disorders or seizures
• History of allergic disease or reactions likely to be exacerbated by any component of the vaccine

Patient-level data for this study will be made available through www.clinicalstudydatarequest.com following the timelines and process described on this site.