Study to Evaluate the Safety and Immunogenicity of a Pandemic Influenza Vaccine in Adults Aged 18 Years and Above

Today, the leading contender for the next pandemic of influenza is H5N1, a strain of avian virus. Prevention and control will depend on the rapid production and worldwide distribution of specific pandemic vaccines. Candidate 'pandemic-like' vaccines must be developed and tested in clinical trials to determine the most optimal formulation and the best vaccination schedule. This study is designed to test in healthy adults aged above 18 years the reactogenicity and immunogenicity of one and two administrations of a candidate pandemic H5N1 vaccine formulated from Split Virus.

This study has 2 phases:

The study ID 107064 corresponds to objectives \& outcome measures evaluated from day 0 until day 51.

The study ID 107217 corresponds to objectives \& outcome measures evaluated at day 180.

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

Eligibility Criteria:
Inclusion Criteria:

* Subjects who the investigator believes that they can and will comply with the requirements of the protocol.
* A male or female aged 18 years or above 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, for 30 days prior to first vaccination, have a negative pregnancy test and must agree to continue such precautions for two months after completion of the vaccination series.

Exclusion Criteria:

* 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 30 days after the second vaccination.
* Administration of interpandemic influenza vaccine between Day 0 and Day 51of the study. Those study participants belonging to risk groups eligible to receive the annual interpandemic influenza vaccine (in accordance with local regulations) can receive the annual vaccination after day 51 and before the end of the study on Day 180.
* Chronic administration (defined as more than 14 days) of immunosuppressants or other immune-modifying drugs within 6 months prior to the first administration of the study vaccine.
* Any confirmed or suspected immunosuppressive or immunodeficient condition, based on medical history and physical examination
* History of chronic alcohol consumption and/or drug abuse.
* History of hypersensitivity to vaccines.
* History of allergic disease or reactions likely to be exacerbated by any component of the vaccine.
* Acute clinically significant pulmonary, cardiovascular, hepatic or renal functional abnormality, as determined by physical examination or laboratory screening tests.
* Major congenital defects or serious chronic disease including any medically significant chronic pulmonary, cardiovascular, renal, neurological, psychiatric or metabolic disorder, as determined by medical history and physical examination. (Subjects suffering from seasonal allergies or asthma under inhalative treatment can be included).
* Acute disease at the time of enrolment.
* Administration of immunoglobulins and/or any blood products within the 3 months preceding the first administration of the study vaccine or during the study.
* Lactating women
* Use of any investigational or non-registered product (drug or vaccine) other than the study vaccine(s) within 30 days prior to the first vaccination, or planned use during the study period.