Evaluate Safety & Immunogenicity of a Pandemic Influenza Vaccine (GSK1562902A) in Children

The present study is designed to evaluate in children (aged between 3 and 9 years) the immunogenicity and safety of different antigen doses of the candidate vaccine (GSK1562902A) administered following a two-administration schedule (21 days apart). Subjects in the control group will receive Fluarix. The Protocol Posting has been updated in order to comply with the FDA Amendment Act, Sep 2007.

This 107066 study is a participating study to the broader NCT00502593 study, which included 2 other studies, the 108498 and 108500 studies. The NCT00502593 study had a staggered design (subjects from each group being enrolled sequentially into 2 age strata, '6-9 years' 1st, and '3-5 years' next) and was run in 3 phases, phases A (Study 107066), B (Study 108498) and C (Study 108500). In each phase, the decision to vaccinate subjects aged 3-5 years and to administer a 2nd injection to subjects aged 6-9 years was made based on safety data collected on Days 0-6 after the 1st injection for the subjects aged 6-9 years. Decision to start Phase B was made on complete safety data including those collected on Day 28 of Phase A (7 days after the 2nd injection) for each age group. A similar approach was to be used to start Phase C. As safety data in Phase A did not raise any safety concerns, Phases B and C were run in parallel.

Eligibility Criteria:
Inclusion Criteria:

* Children who the investigator believes that their parents/guardians can and will comply with the requirements of the protocol.
* Children aged between and including 3 and 9 years of age at the time of first vaccination.
* Written informed consent obtained from the parent(s) or guardian of the subject.
* Healthy children as established by medical history and clinical examination before entering the study.
* Subjects who are likely to reside in the vicinity of the study center for the duration of the study.

Exclusion criteria:

* Use of any investigational or non-registered product (drug or vaccine) other than the investigational vaccine within 30 days prior to the enrolment in this study, or planned use during the study period.
* Administration of 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 30 days after the second vaccination, with the exception of routine childhood inoculations which cannot be delayed, but which must not be administered on the same day as the investigational vaccine candidate.
* Administration of the interpandemic influenza vaccine 21 days prior to Day 0 or up to Day 51.
* Chronic administration (defined as more than 14 days) of immunosuppressants or other immune-modifying drugs within six months prior to the enrolment in this study.
* Any chronic drug therapy to be continued during the study period, with the exception of inhalative treatment for seasonal allergies or asthma.
* Any confirmed or suspected immunosuppressive or immunodeficient condition, based on medical history and physical examination.
* Acute or chronic clinically significant pulmonary, cardiovascular, hepatic or renal functional abnormality, as determined by medical history and physical examination.
* History of hypersensitivity to vaccines.
* History of allergic disease or reactions likely to be exacerbated by any component of the vaccines used in this study.
* History of any neurological disorders or seizures.
* Acute disease at the time of enrolment.
* Administration of immunoglobulins and/or any blood products within the three months prior to the enrolment in this study or planned during the study.
* Any condition which, in the opinion of the investigator, renders the subject unfit for participation in the study