Immunogenicity and Safety Study of GlaxoSmithKline (GSK) Biologicals' Meningococcal Conjugate Vaccine (GSK134612) When Co-administered With Boostrix® in Subjects Between 11 and 25 Years of Age

Inclusion Criteria

• Healthy subjects as established by medical history and clinical examination before entering into the study.
• Subjects and subjects' parent(s)/Legally Acceptable Representative(s) [LAR(s)] who, in the opinion of the investigator, can and will comply with the requirements of the protocol.
• A male or female between, and including, 11 and 25 years of age at the time of the first vaccination.
• Written informed consent obtained from the subject/from the parent(s)/LAR(s) of the subject.
• Written informed assent obtained from the subjects when applicable according to local regulations.
• Female subjects of non-childbearing potential may be enrolled in the study.
• Non-childbearing potential is defined as pre-menarche, current tubal ligation, hysterectomy or ovariectomy.
• Female subjects of childbearing potential may be enrolled in the study, if the subject:
• has practiced adequate contraception for 30 days prior to vaccination, and
• has a negative pregnancy test on the day of vaccination, and
• has agreed to continue adequate contraception during the entire treatment period and for two months after completion of the vaccination series.

Exclusion Criteria

• Child in care.
• Use of any investigational or non-registered product other than the study vaccines 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 within six months prior to the first vaccine dose. For corticosteroids, this will mean prednisone ≥ 10 mg/day, or equivalent. Inhaled and topical steroids are allowed.
• Planned administration/administration of a vaccine not foreseen by the study protocol in the period starting 30 days before the first dose of vaccine and ending 30 days after the last dose of vaccine, with the exception of licensed inactivated influenza vaccine.
• 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.
• Previous vaccination with a meningococcal vaccine.
• History of meningococcal disease.
• Vaccination with a DTP-containing vaccine within the previous five years.
• History of serious allergic reaction following any other DTP-containing vaccine or any component of the study vaccines.
• History of encephalopathy within seven days following administration of a previous dose of pertussis vaccine that is not attributable to another identifiable cause.
• Temperature of ≥ 40.5°C (105°F) within 48 hours of receipt of a previous dose of DTP vaccine, not due to another identifiable cause.
• Collapse or shock-like state within 48 hours of receipt of a previous dose of DTP vaccine.
• Seizures with or without fever within three days of a previous dose of DTP vaccine.
• Severe Arthus-type hypersensitivity reactions following a prior dose of tetanus toxoid (TT) within the previous ten years.
• Any confirmed or suspected immunosuppressive or immunodeficient condition, based on medical history and physical examination during the study period.
• History of any reaction or hypersensitivity likely to be exacerbated by any component of the vaccine(s).
• Progressive neurologic disorder, uncontrolled epilepsy or progressive encephalopathy.
• History of any neurologic disorders or seizures, including Guillain-Barré syndrome (GBS). History of a simple, single febrile seizure is permitted.
• Bleeding disorders, such as haemophilia or thrombocytopenia, or subjects on anticoagulant therapy.
• Administration of immunoglobulins and/or any blood products within the three months preceding the first dose of study vaccine, or planned administration during the study period.
• Pregnant or lactating female.
• Female planning to become pregnant or planning to discontinue contraceptive precautions.
• Family history of congenital or hereditary immunodeficiency.
• Major congenital defects or ser