Evaluate Reactogenicity & Immunogenicity of an Influenza Pandemic Candidate Vaccine (GSK1562902A) in Primed Adults

Inclusion Criteria:

• Subjects who the investigator believes can and will comply with the requirements of the protocol should be enrolled in the study.
• For previously primed subjects: participation in the primary study (NCT00309634).
• For unprimed subjects: male or female between and including, 19 and 61 years of age at the time of the first vaccination.
• Written informed consent obtained from the subject.
• Healthy subjects as established by medical history and clinical examination 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 vaccine(s) within 30 days preceding the first dose of study vaccine, or planned use during the study period.
• For unprimed subjects who did not participate in the primary study (NCT00309634): Chronic administration (defined as more than 14 days) of immunosuppressants or other immune-modifying drugs within six months prior to the first vaccine dose.
• Planned administration/ administration of a licenced vaccine not foreseen by the study protocol within 2 weeks (for inactivated vaccines) or 4 weeks (for live vaccines) of the first dose of vaccine(s).
• 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 (pharmaceutical product or device).
• Applicable for control group only: previous vaccination with a pandemic candidate vaccine or a vaccine containing the investigational vaccine adjuvant.
• History of hypersensitivity to vaccines.
• Any confirmed or suspected immunosuppressive or immunodeficient condition, based on medical history and physical examination (no laboratory testing required).
• History of allergic disease or reactions likely to be exacerbated by any component of the vaccine(s).
• Major congenital defects or serious chronic illness.
• History of any neurological disorders or seizures.
• Acute disease at the time of enrolment.
• Acute or chronic, clinically significant pulmonary, cardiovascular, hepatic or renal functional abnormality, as determined by physical examination or laboratory screening tests.
• Serious chronic disease including any medically significant chronic pulmonary, cardiovascular, renal, neurological, psychiatric or metabolic disorder, as determined by medical history and physical examination.
• Any condition which, in the opinion of the investigator, prevents the subject from participation in the study.
• Lactating female.
• History of chronic alcohol consumption and/or drug abuse