Evaluation of Safety and Immunogenicity of GSK Bio's Influenza Vaccine GSK576389A After Repeated Vaccination in Elderly Adults

Since influenza vaccines are administered every year because of the frequent change in their antigenic composition, the safety and immunogenicity profile of GSK Biologicals' influenza vaccine GSK576389A will be re-evaluated after repeated vaccine administration. In this study, the subjects previously enrolled in study 104887 will receive a dose with the 2007-2008 season's formulations of Fluarix or GSK576389A. Only subjects who were previously enrolled in study 104887 are eligible for participation in this study.

This study is a year 2 revaccination study. First year revaccination was done in study 104887 (NCT00386698). Primary study was study 104886 (NCT00318149). This study involves 2 age groups (based on primary study):

Subjects enrolled in the ≥ 65 years age group in the primary study. Subjects enrolled in the 18-40 years age group in the primary study.

The Protocol Posting has been updated in order to comply with the FDA Amendment Act, Sep 2007

Eligibility Criteria:
Inclusion Criteria:

* Subjects who were previously vaccinated with GlaxoSmithKline Biologicals Fluarix™ or GSK576389A investigational vaccines in the 104887 study (NCT00386698).
* Subjects who the investigator believes that they can and will comply with the requirements of the protocol should be enrolled in the study.
* A male or female aged between 19 and 42 years or 66 years and older at the time of the vaccination.
* Written informed consent obtained from the subject.
* Free of an acute aggravation of the health status as established by clinical evaluation before entering into the study.
* If the subject is female, she must be of non-childbearing potential or if she is of childbearing potential, she must practice adequate contraception for 30 days prior to vaccination, have a negative pregnancy test and continue such precautions for 2 months after completion of the vaccination series.

Exclusion Criteria:

* Use of any investigational or non-registered product (drug or vaccine) other than the study vaccines within 30 days prior to vaccination, or planned use during the study period.
* Administration of other licensed vaccines within 2 weeks (for inactivated vaccines) or 4 weeks (for live vaccines) prior to enrolment in this study. Planned administration of a vaccine not foreseen by the study protocol up to 21 days after vaccination.
* Planned administration of an influenza vaccine other than the study vaccines during the entire study period.
* Vaccination against influenza since January 2007 with the Northern Hemisphere 2007/2008 influenza vaccine or 2006/2007 influenza vaccine.
* History of confirmed influenza infection since the date of previous vaccination.
* Chronic administration (defined as more than 14 days) of immunosuppressants or other immune-modifying drugs within six months prior to the administration of the study vaccine. (For corticosteroids, this will mean prednisone, or equivalent, ≥0.5 mg/kg/day. Inhaled and topical steroids are allowed.)
* Any confirmed or suspected immunosuppressive or immunodeficient condition, based on medical history and physical examination (no laboratory testing required).
* History of hypersensitivity to a previous dose of influenza vaccine.
* History of allergy or reactions likely to be exacerbated by any component of the vaccine(s)
* Acute (active) clinically significant pulmonary, cardiovascular, hepatic or renal functional abnormality, as determined by clinical evaluation (medical history and medical history directed physical examination) or pre-existing laboratory screening tests.
* Acute disease at the time of enrolment. (Acute disease is defined as the presence of a moderate or severe illness with or without fever. All vaccines can be administered to persons with a minor illness such as diarrhea, mild upper respiratory infection with or without low-grade febrile illness, i.e. Axillary temperature \<37.5°C / Oral temperature of \<37.5°C).
* Administration of immunoglobulins and/or any blood products within the three months preceding the first administration of the study vaccine or planned administration during the study.
* Any medical conditions in which intramuscular injections are contraindicated.
* Pregnant or lactating female.
* Female planning to become pregnant or planning to discontinue contraceptive precautions.