Immunogenicity and Safety of GSK Biologicals' Infanrix Hexa in Infants

Inclusion Criteria: * Subjects who the investigator believes that their parent/guardian can and will comply with the requirements of the protocol should be enrolled in the study. * A male or female between, and including, 6 and 12 weeks of age at the time of the first vaccination. * Born after a gestation period of 36 to 42 weeks inclusive. * Healthy subjects as established by medical history before entering into the study. * Written informed consent obtained from the parent or guardian of the subject. Exclusion Criteria: * Use of any investigational or non-registered product within 30 days preceding the first dose of study vaccine, or planned use during the study period. * Chronic administration of immunosuppressants or other immune-modifying drugs from birth until first primary vaccination dose.. * Administration of immunoglobulins and/or any blood products since birth or planned administration during the study period. * Concurrently participating in another clinical study, at any time during the study period, in which the subject has been or will be exposed to an investigational or a non-investigational product. * Major congenital defects or serious chronic illness. * Evidence of previous or intercurrent diphtheria, tetanus, pertussis, poliomyelitis, hepatitis B and/or Hib vaccination or disease. * Any confirmed or suspected immunosuppressive or immunodeficient condition, based on medical history. * History of allergic disease or reactions likely to be exacerbated by any component of the vaccines. * The following condition is temporary or self limiting and a subject may be vaccinated once the condition has resolved and no other exclusion criteria are met: * Current febrile illness or axillary temperature of ≥ 37.5 ºC or other moderate to severe illness within 24 hours of study vaccine administration.