• Anti-PRP antibody concentrations [ Time Frame: 1 month after the primary vaccination course and post-booster vaccination. ] [ Designated as safety issue: No ]
• hSBA-MenC titres [ Time Frame: 1 month after the primary vaccination course and post-booster vaccination ] [ Designated as safety issue: No ]
• hSBA-MenY titres [ Time Frame: 1 month after the primary vaccination course and post-booster vaccination ] [ Designated as safety issue: No ]
• Anti-diphtheria antibody concentrations [ Time Frame: 1 month after the primary vaccination course ] [ Designated as safety issue: No ]
• Anti-tetanus antibody concentrations [ Time Frame: 1 month after the primary vaccination course ] [ Designated as safety issue: No ]
• Anti-pertussis toxoid antibody concentrations [ Time Frame: 1 month after the primary vaccination course ] [ Designated as safety issue: No ]
• Anti-Filamentous Haemagglutinin antibody concentrations [ Time Frame: 1 month after the primary vaccination course ] [ Designated as safety issue: No ]
• Anti-pertactin antibody concentrations [ Time Frame: 1 month after the primary vaccination course. ] [ Designated as safety issue: No ]
• Anti-poliovirus 1 antibody titres [ Time Frame: 1 month after the primary vaccination course ] [ Designated as safety issue: No ]
• Anti-poliovirus 2 antibody titres [ Time Frame: 1 month after the primary vaccination course ] [ Designated as safety issue: No ]
• Anti-poliovirus 3 antibody titres [ Time Frame: 1 month after the primary vaccination course. ] [ Designated as safety issue: No ]
• Number of Subjects Reporting Fever > 39.5°C/103.1°F [ Time Frame: In the 4-day follow-up period following any dose of the primary vaccination and following the booster dose. ] [ Designated as safety issue: No ]
• Anti-measles antibody concentrations [ Time Frame: Post-booster vaccination ] [ Designated as safety issue: No ]
• Anti-mumps antibody titre [ Time Frame: Post-booster vaccination. ] [ Designated as safety issue: No ]
• Anti-rubella antibody concentrations [ Time Frame: Post-booster vaccination ] [ Designated as safety issue: No ]
• Anti-varicella antibody titres. [ Time Frame: Post-booster vaccination ] [ Designated as safety issue: No ]

• Anti-PRP antibody concentrations [ Time Frame: 1 month after the primary vaccination course, pre-booster and post-booster vaccination ] [ Designated as safety issue: No ]
• rSBA-MenC titres [ Time Frame: 1 month after the primary vaccination course, pre-booster and post-booster vaccination ] [ Designated as safety issue: No ]
• rSBA-MenY titres [ Time Frame: 1 month after the primary vaccination course, pre-booster and post-booster vaccination ] [ Designated as safety issue: No ]
• Anti-Polysaccharide C antibody concentrations [ Time Frame: 1 month after the primary vaccination course, pre-booster and post-booster vaccination ] [ Designated as safety issue: No ]
• Anti-Polysaccharide Y antibody concentrations [ Time Frame: 1 month after the primary vaccination course, pre-booster and post-booster vaccination ] [ Designated as safety issue: No ]
• Anti-diphtheria antibody concentrations [ Time Frame: 1 month after the primary vaccination course ] [ Designated as safety issue: No ]
• Anti-tetanus antibody concentrations [ Time Frame: 1 month after the primary vaccination course ] [ Designated as safety issue: No ]
• Anti-Hepatitis B surface antigen antibody concentrations [ Time Frame: 1 month after the primary vaccination course ] [ Designated as safety issue: No ]
• hSBA-MenY titres [ Time Frame: 1 month after the primary vaccination course, pre-booster and post-booster vaccination ] [ Designated as safety issue: No ]
• Anti-pertussis antibody concentrations [ Time Frame: 1 month after the primary vaccination course. ] [ Designated as safety issue: No ]
• Anti-poliovirus types 1, 2, and 3 antibody titres. [ Time Frame: 1 month after the primary vaccination course ] [ Designated as safety issue: No ]
• Anti-measles antibody concentrations in initially seronegative subjects [ Time Frame: Post-booster vaccination. ] [ Designated as safety issue: No ]
• Anti-mumps antibody titres in initially seronegative subjects. [ Time Frame: Post-booster vaccination ] [ Designated as safety issue: No ]
• hSBA-MenC titres [ Time Frame: 1 month after the primary vaccination course, pre-booster and post-booster vaccination ] [ Designated as safety issue: No ]
• Anti-rubella antibody concentrations in initially seronegative subjects [ Time Frame: Post-booster vaccination ] [ Designated as safety issue: No ]
• Anti-varicella antibody titres in initially seronegative subjects. [ Time Frame: Post-booster vaccination. ] [ Designated as safety issue: No ]
• Number of subjects reporting Local and General Solicited Adverse Events [ Time Frame: Within 4 days (Day 0 through Day 3) following each vaccine dose. ] [ Designated as safety issue: No ]
• Number of subjects reporting unsolicited symptoms [ Time Frame: Within 31 days (Day 0-30) following each dose of vaccine dose ] [ Designated as safety issue: No ]
• Number of subjects reporting Serious Adverse Events (SAEs) [ Time Frame: From Dose 0 through 6 months after the last primary dose or until administration of the booster dose (whichever comes first); and from the booster dose of Hib-MenCY-TT vaccine and PedvaxHIB through the end of the 6-month safety follow-up. ] [ Designated as safety issue: No ]
• Number of subjects reporting specific adverse events [ Time Frame: From Dose 0 through 6 months after the last primary dose or until administration of the booster dose (whichever comes first); and from the booster dose of Hib-MenCY-TT vaccine and PedvaxHIB through the end of the 6-month safety follow-up. ] [ Designated as safety issue: No ]
• % subjects with at least a 4-fold rise in anti-H1N1, anti-H3N2, and anti-B ab titers, measured by hemagglutination inhibition assay (HIA), in subjects who received 1 or 2 doses of flu vaccine within the same flu season concomitantly with study vaccine. [ Time Frame: Post-booster vaccination ] [ Designated as safety issue: No ]
• Incidence of increased circumferential swelling at the injected limb(s). [ Time Frame: Within 4 days (Day 0 to Day 3) after booster vaccination ] [ Designated as safety issue: No ]
• Incidence of general symptoms specific to measles, mumps, rubella, and varicella vaccination (fever, rash/exanthem, parotid/salivary gland swelling, and any suspected signs of meningism including febrile convulsions). [ Time Frame: Within 43 days (Day 0 through Day 42) after booster vaccination ] [ Designated as safety issue: No ]

• hSBA-MenC titres [ Time Frame: 1 month after the primary vaccination course, pre-booster and post-booster vaccination ]
• hSBA-MenY titres [ Time Frame: 1 month after the primary vaccination course, pre-booster and post-booster vaccination ]
• Anti-PRP antibody concentrations [ Time Frame: 1 month after the primary vaccination course, pre-booster and post-booster vaccination ]
• rSBA-MenC titres [ Time Frame: 1 month after the primary vaccination course, pre-booster and post-booster vaccination ]
• rSBA-MenY titres [ Time Frame: 1 month after the primary vaccination course, pre-booster and post-booster vaccination ]
• Anti-Polysaccharide C antibody concentrations [ Time Frame: 1 month after the primary vaccination course, pre-booster and post-booster vaccination ]
• Anti-Polysaccharide Y antibody concentrations [ Time Frame: 1 month after the primary vaccination course, pre-booster and post-booster vaccination ]
• Anti-diphtheria antibody concentrations [ Time Frame: 1 month after the primary vaccination course ]
• Anti-tetanus antibody concentrations [ Time Frame: 1 month after the primary vaccination course ]
• Anti-Hepatitis B surface antigen antibody concentrations [ Time Frame: 1 month after the primary vaccination course ]
• Anti-pertussis, anti-filamentous haemagglutinin and anti-pertactin antibody concentrations [ Time Frame: 1 month after the primary vaccination course. ]
• Anti-poliovirus types 1, 2, and 3 antibody titres. [ Time Frame: 1 month after the primary vaccination course ]
• Anti-measles antibody concentrations in initially seronegative subjects [ Time Frame: Post-booster vaccination. ]
• Anti-mumps antibody titres in initially seronegative subjects. [ Time Frame: Post-booster vaccination ]
• Anti-rubella antibody concentrations in initially seronegative subjects [ Time Frame: Post-booster vaccination ]
• Anti-varicella antibody titres in initially seronegative subjects. [ Time Frame: Post-booster vaccination. ]
• Incidence of local and general solicited adverse events [ Time Frame: Within 4 days (Day 0 through Day 3) following each vaccine dose. ]
• Incidence of unsolicited symptoms [ Time Frame: Within 31 days (Day 0-30) following each dose of vaccine dose ]
• Incidence of Serious Adverse Events [ Time Frame: From Dose 0 through 6 months after the last primary dose or until administration of the booster dose (whichever comes first); and from the booster dose of Hib-MenCY-TT vaccine and PedvaxHIB through the end of the 6-month safety follow-up. ]
• Occurrence of specific adverse events of new onset of chronic illness(es), rash, and conditions prompting emergency room visits and physician office visits not related to common illnesses [ Time Frame: From Dose 0 through 6 months after the last primary dose or until administration of the booster dose (whichever comes first); and from the booster dose of Hib-MenCY-TT vaccine and PedvaxHIB through the end of the 6-month safety follow-up. ]
• % subjects with at least a 4-fold rise in anti-H1N1, anti-H3N2, and anti-B ab titers, measured by hemagglutination inhibition assay (HIA), in subjects who received 1 or 2 doses of flu vaccine within the same flu season concomitantly with study vaccine. [ Time Frame: Post-booster vaccination ]
• Incidence of increased circumferential swelling at the injected limb(s). [ Time Frame: Within 4 days (Day 0 to Day 3) after booster vaccination ]
• Incidence of general symptoms specific to measles, mumps, rubella, and varicella vaccination (fever, rash/exanthem, parotid/salivary gland swelling, and any suspected signs of meningism including febrile convulsions). [ Time Frame: Within 43 days (Day 0 through Day 42) after booster vaccination ]

This study evaluates the immunogenicity and consistency of 3 Hib-MenCY-TT vaccine lots and the safety and immunogenicity of Hib-MenCY-TT vaccine compared to a control group receiving licensed Hib conjugate vaccine, when each are co-administered with Pediarix® to healthy infants at 2, 4, and 6 months of age. The study will also evaluate the safety and immunogenicity of Hib-MenCY-TT vaccine compared to a control group receiving licensed Hib conjugate vaccine, when each are co-administered with M-M-R® II and Varivax® at 12 to 15 months of age.

The subjects from this study will participate in one of three cohorts:

• US Safety and Immunogenicity (Cohort 1): All immunogenicity analyses in the primary and booster phases will be evaluated in this cohort. These subjects will also contribute to the safety analyses in the primary and booster phases.
• Safety Only (Cohort 2): Only safety objectives will be assessed in the primary and booster phases for this cohort.
• Non-US Safety and Immunogenicity (Cohort 3): Only descriptive immunogenicity results in the primary and booster phases will be reported for this cohort. These subjects will also contribute to the safety analyses in the primary and booster phases.

Treatment allocation:

Primary phase: Subjects will be randomized with balanced allocation (1:1:1:1) to 1 of the 4 treatment groups and with a stratification according to the cohort. Assignment to a cohort will be based on study site.

Booster phase: Subjects who received Hib-MenCY-TT vaccine in the primary phase will receive a booster dose of Hib-MenCY-TT vaccine. Subjects who received ActHIB in the primary phase will receive a booster dose of PedvaxHIB.

During the 3-dose primary vaccination course, co-administration of Prevnar, Synagis, and/or rotavirus vaccine is permitted; co-administration of influenza vaccine is permitted at dose 3.

During the booster vaccination, co-administration of Prevnar, hepatitis A vaccine and influenza vaccine is permitted for all subjects in Cohort 1, 2 and 3; and co-administration of measles, mumps, rubella and varicella vaccine is permitted for all subjects in Cohort 2 and 3.

The study will be conducted in a double-blind fashion with regard to consistency of the 3 manufacturing lots of Hib-MenCY-TT vaccine and single-blind fashion for Hib-MenCY-TT vaccine versus monovalent Hib vaccine. The parents/guardians will be blinded up to collection of all data pertaining to the period up to one month after booster vaccination. Therefore, the extended safety follow-up after the booster dose will be conducted in an unblinded manner. The person administering the vaccines will ensure that the parent/guardian does not see the vaccine vial used in reconstituting the vaccine. Due to the differences in the presentations of the candidate Hib-MenCY-TT vaccine and control vaccines, it is not possible to blind study personnel who administer the vaccines.

• Haemophilus Influenzae Type b Infection
• Meningococcal Infection

• Biological: GSK Biologicals' Haemophilus influenzae type b and Neisseria meningitidis 792014 vaccine
• Biological: ActHIB
• Biological: PedvaxHIB
• Biological: Prevnar
• Biological: M-M-R II
• Biological: Pediarix
• Biological: Varivax

• Experimental: Primed with 3 doses of Hib-MenCY-TT vaccine Lot A co-administered with Pediarix. Boosted with 1 dose of Hib-MenCY-TT vaccine, with co-administration of M-M-R II and Varivax to all US subjects in Cohort 1.
• Experimental: Primed with 3 doses of Hib-MenCY-TT vaccine Lot B co-administered with Pediarix. Boosted with 1 dose of Hib-MenCY-TT vaccine, with co-administration of M-M-R II and Varivax to all US subjects in Cohort 1
• Experimental: Primed with 3 doses of Hib-MenCY-TT vaccine Lot C co-administered with Pediarix. Boosted with 1 dose of Hib-MenCY-TT vaccine, with co-administration of M-M-R II and Varivax to all US subjects in Cohort 1.
• Active Comparator: Primed with 3 doses of ActHIB co-administered with Pediarix. Boosted with 1 dose of PedvaxHIB, with co-administration of M-M-R II and Varivax to all US subjects in Cohort 1

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 enrollment.
• 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). (Synagis® [palivizumab, MedImmune], Prevnar (Prevenar), rotavirus vaccine, and influenza vaccine are allowed.
• Previous vaccination against Neisseria meningitidis, Haemophilus influenzae type b, diphtheria, tetanus, pertussis, and/or poliovirus; more than one previous dose of hepatitis B vaccine.
• 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 (no laboratory testing is required).
• 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).

Additional specific criteria for the US subjects in Cohort 1. In addition, for Cohorts 2 and 3, subjects should not be administered M-M-R II and Varivax if any of these criteria apply:

• History of measles, mumps, rubella or varicella.
• Previous vaccination against measles, mumps, rubella or varicella.
• Hypersensitivity to any component of the vaccines, including gelatin or neomycin.
• Patients receiving immunosuppressive therapy.
• Individuals with blood dyscrasias, leukemia, lymphomas of any type, or other malignant neoplasms affecting the bone marrow or lymphatic systems.
• Individuals with primary and acquired immunodeficiency states.
• Individuals with a family history of congenital or hereditary immunodeficiency, until the immune competence of the potential vaccine recipient is demonstrated.
• Individuals with active tuberculosis.
• Acute disease at time of booster vaccination.