Immunogenicity and Safety Study of a GlaxoSmithKline Biologicals' Candidate Influenza Vaccine in Healthy Children

Inclusion Criteria

For all subjects:

• Subjects who the investigator believes that they and/or their Legally Acceptable Representative(s) (LAR) can and will comply with the requirements of the protocol.
• Written informed consent obtained from the subject/from the LAR(s).

For unprimed subjects:

• A male or female child aged 18 to 47 months at the time of the first vaccination.
• Children who did not have influenza vaccine in a previous season.

For primed subjects from study NCT00764790:

• Children who received Fluarix™ in the 111751 study NCT00764790.

Exclusion Criteria

• Use of any investigational or non-registered product other than the study vaccine within 30 days preceding the first dose of study vaccine, or planned use during the study period.
• History of hypersensitivity to any vaccine.
• History of allergy or reactions likely to be exacerbated by any component of the vaccine.
• Planned administration/ administration of a vaccine not foreseen by the study protocol during the period starting one month before and ending 28 days after each dose of vaccine(s).
• Acute or chronic clinically significant pulmonary, cardiovascular, hepatic or renal functional abnormality, as determined by medical history and physical examination.
• Acute disease at the time of enrolment.
• History of Guillain Barré syndrome within 6 weeks of receipt of prior inactivated influenza virus vaccine.
• Receipt of another seasonal influenza vaccine outside of this study, during current (2009-2010) flu season.
• Any confirmed or suspected immunosuppressive or immunodeficient condition based on medical history and physical examination.
• Chronic administration of immunosuppressants or other immune-modifying drugs within six months prior to the first vaccination Inhaled and topical steroids are allowed.
• Administration of immunoglobulins and/or blood products within the 3 month preceding the first dose of study vaccine or planned administration during the 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.