Inclusion Criteria:

• Subjects who the investigator believes that they can and will comply with the requirements of the protocol.
• Male or female subjects who have received Boostrix™, Boostrix™-US formulation or the investigational vaccine formulation in the study 263855/029.
• Written informed consent obtained from the subject.
Additional criteria to be checked before the booster vaccination.
• Healthy subjects as established by medical history and clinical examination.
• Female subjects of non-childbearing potential may receive the booster vaccine.
• Female subjects of childbearing potential may receive the booster vaccine, if the subject:
- practices/has practiced adequate contraception for 30 days prior to vaccination, and
- has a negative pregnancy test on the day of vaccination, and
- agrees to continue adequate contraception during the entire booster epoch.


Exclusion Criteria:

Exclusion criteria to be checked at study entry:
• Previous booster vaccination against diphtheria, tetanus, or pertussis since the dose received in the study 263855/029.
• History of diphtheria, tetanus, or laboratory confirmed pertussis disease.
• Any confirmed or suspected immunosuppressive or immunodeficiency condition, based on medical history and physical examination.
• History of any reaction or hypersensitivity likely to be exacerbated by any component of the vaccine.
• Occurrence of transient thrombocytopenia or neurological complications following an earlier immunisation against diphtheria and/or tetanus.
• Occurrence of any of the following adverse event after a previous administration of a DTP vaccine :
- hypersensitivity reaction to any component of the vaccine,
- encephalopathy of unknown aetiology occurring within seven days following previous vaccination with pertussis-containing vaccine,
- fever >= 40 °C (axillary temperature) within 48 hours of vaccination not due to another identifiable cause,
- collapse or shock-like state within 48 hours of vaccination,
- convulsions with or without fever, occurring within three days of vaccination.
• Acute or chronic, clinically significant pulmonary, cardiovascular, hepatic or renal functional abnormality, as determined by physical examination or laboratory screening tests.
Additional exclusion criteria to be checked for subjects before the booster vaccination administration:
• Use of any investigational or non-registered product other than the study vaccine(s) within 30 days preceding the booster 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 booster dose.
• Administration of a vaccine not foreseen by the study protocol within 30 days prior to booster vaccination, or planned administration during the active 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.
• Administration of immunoglobulins and/or any blood products within the three months preceding the booster dose or planned administration during the study period.
• Acute disease and/or fever at the time of enrolment.
- Fever is defined as temperature ≥ 37.5°C on oral, axillary or tympanic setting.
- Subjects with a minor illness without fever may be enrolled at the discretion of the investigator.
• Pregnant or lactating female.
• Female planning to become pregnant or planning to discontinue contraceptive precautions.

• Belgium (click to view all sites in Belgium)
• GSK Investigational Site
  Leuven, 3000; Completed;
  Contact: Karel Hoppenbrouwers, Principal Investigator, .
• GSK Investigational Site
  Wilrijk, 2610; Completed;
  Contact: Pierre A Van Damme, Principal Investigator, .
• GSK Investigational Site
  Bruxelles, 1200; Completed;
  Contact: Etienne Sokal, Principal Investigator, .