Study to Evaluate the Safety and Immune Response of Two-Doses of Candidate Influenza Vaccine GSK 1557484A in Adults

The purpose of this study is to evaluate the safety and immune response of two-doses of GSK Biologicals' candidate influenza vaccine GSK 1557484A with or without adjuvant in adults. The Protocol Posting has been updated in order to comply with the FDA Amendment Act, Sep 2007.

The study has five core arms and the stratification is based on site and age. In addition, there are 4 possible contingent groups of which 2 will be studied based on an analysis concerning immunogenicity performance at Day 42 in core groups above.

Eligibility Criteria:
Inclusion Criteria:

* Male and female adults 18 to 64 years of age at time of first vaccination, inclusive.
* Good general health as assessed by medical history and physical examination.
* Access to a consistent means of telephone contact
* Written informed consent obtained from the subject.
* Comprehension of the study requirements, expressed availability for the required study period, and ability to attend scheduled visits.
* Subjects who the investigator believes that they can and will comply with the requirements of the protocol should be enrolled in the study.

Exclusion Criteria:

* Presence of significant acute or chronic, uncontrolled medical or psychiatric illness
* Presence of evidence of substance abuse or of neurological or psychiatric diagnoses which, although stable, are deemed by the investigator to render the potential subject unable/unlikely to provide accurate safety reports.
* Blood pressure abnormalities
* Diagnosed with cancer, or treatment for cancer, within 3 years.
* Persons with a history of cancer who are disease-free without treatment for 3 years or more are eligible.
* Persons with a history of histologically-confirmed basal cell carcinoma of the skin successfully treated with local excision only are excepted and may enroll, but other histologic types of skin cancer are exclusionary.
* Women who are disease-free 3 years or more after treatment for breast cancer and receiving long-term prophylactic tamoxifen are excepted and may enroll.
* Presence of an oral temperature ≥ 37.8º C, or acute symptoms greater than "mild" severity on the scheduled date of first vaccination.
* Any confirmed or suspected immunosuppressive or immunodeficient condition including history of human immunodeficiency virus (HIV) infection.
* Receipt of cytotoxic or immunosuppressive drug within 6 months of study enrollment.
* Any significant disorder of coagulation or treatment with Coumadin derivatives or heparin.
* Administration of any non-influenza vaccines within 30 days before study enrollment or during the study period.
* Use of any investigational or non-registered product (drug or vaccine) or planned participation in another investigational study within 30 days prior to study enrollment, or during the study period.
* Receipt of any immunoglobulins and/or any blood products within 3 months of study enrollment or planned administration of any of these products during the study period.
* Any known or suspected allergy to any constituent of influenza vaccines.
* Known pregnancy or a positive urine beta-human chorionic gonadotropin (ß-hCG) test result prior to dosing on Study Days 0 or 21.
* Lactating or nursing.
* Women of child bearing potential who lack a history of reliable contraceptive practices.
* Known receipt of analgesic or antipyretic medication on the day of treatment