Safety of Hib-MenCY-TT Vaccine Versus Licensed Hib Conjugate Vaccine, Given at 2, 4, 6 and 12 to 15 Months of Age

Inclusion Criteria: * Subjects for whom the investigator believes that parents/guardians can and will comply with the requirements of the protocol. * A male or female between, and including, 6 and 12 weeks of age at the time of the first 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. * Born after 36 weeks gestation. * Infants who have not received a previous dose of hepatitis B vaccine or those who have received only 1 dose of hepatitis B vaccine administered at least 30 days prior to enrolment. * Infants may have received a birth dose of Bacillus Calmette-Guérin (BCG) vaccine. Exclusion criteria: Use of any investigational or non-registered product (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 (defined as more than 14 days) of immunosuppressants or other immune-modifying drugs since birth. * Planned administration/ administration of a vaccine not foreseen by the study protocol within 30 days of the first dose of study vaccine(s). * Previous vaccination against Neisseria meningitidis, Haemophilus influenzae type b, diphtheria, tetanus, pertussis, and/or poliovirus; more than one previous dose of hepatitis B vaccine. * In country(ies) where Prevnar will be provided by GSK Biologicals, previous vaccination with Prevnar. * History of Neisseria meningitidis, Haemophilus influenzae type b, diphtheria, tetanus, pertussis, hepatitis B, and/or poliovirus disease. * Any confirmed or suspected immunosuppressive or immunodeficient condition based on medical history and physical examination. * History of allergic disease or reactions likely to be exacerbated by any component of the vaccines, including dry natural latex rubber. * Major congenital defects or serious chronic illness. * History of any neurologic disorders or seizures. * Acute disease at time of enrollment. * Administration of immunoglobulins and/or any blood products since birth or planned administration during the study period. * Concurrent participation 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 (pharmaceutical product or device).