Immune Memory of DTPw-HBV/Hib Vaccine Following Primary Vaccination, Immuno & Reacto of a Booster Dose Given in Infants

Immune Memory of GSK's DTPw-HBV/Hib Vaccine by Giving Plain PRP Polysaccharide at 10 Mths. Immuno & Reacto of a Booster Dose of DTPw-HBV/Hib or DTPw-HBV or DTPw-HBV+Hib at 15-18 Mths in Infants Previously Primed With DTPw-HBV/Hib

To assess the immune memory following primary vaccination of DTPw-HBV/Hib vaccine and to assess immunogenicity and reactogenicity of a booster dose given at 15 - 18 months of age.

• Subjects who received DTPw-HBV/Hib in the primary vaccination without HBV at birth will be randomised (1:3 ratio) to receive either: Plain PRP at 10 months of age followed by DTPw-HBV at 15-18 months of age or DTPw-HBV/Hib at 15-18 months of age.
• Subjects who received DTPw-HBV + Hib in the primary vaccination without HBV at birth will receive DTPw-HBV + Hib as a booster.
• Subjects who received DTPw-HBV/Hib in the primary vaccination with HBV at birth will receive DTPw-HBV/Hib vaccine as a booster.

Inclusion criteria:

For subjects receiving Plain PRP followed by DTPw-HBV:

Male or female infant, 10 to 11 months of age, who previously completed the three-dose primary vaccination course with the DTPw-HBV/Hib vaccine.

For subjects receiving DTPw-HBV/Hib or DTPw-HBV + Hib:

Male or female infant, 15-18 months of age, who previously completed the three-dose primary vaccination course with the DTPw-HBV/Hib vaccine.

For all subjects:

• Subjects who the investigator believes that their parent/guardian can and will comply with the requirements of the protocol.
• Free of obvious health problems as established by medical history and clinical examination

Exclusion criteria:

• Use of any investigational or non-registered product other than the study vaccine(s) within 30 days preceding administration of the study vaccine, or planned use during the study period.
• Chronic administration of immunosuppressants or other immune-modifying drugs within six months prior to administration of the study vaccine.
• Planned administration/administration of a vaccine not foreseen by the study protocol starting 30 days before and ending 30 days after administration of the study vaccine with the exception of oral polio vaccine.