Study to Evaluate the Safety and Immunogenicity of an Investigational Pneumococcal Vaccine in the Elderly Population

Inclusion Criteria: * Subjects who the investigator believes that they can and will comply with the requirements of the protocol. * A male or female between 65 and 85 years of age at the time of the first vaccination. * Written informed consent obtained from the subject. Exclusion Criteria: * Previous vaccination against Streptococcus pneumoniae. * Acute or chronic, clinically significant pulmonary, cardiovascular, hepatic or renal functional abnormality, as determined by physical examination or laboratory tests. * Acute disease at the time of enrolment. * History of documented radiologically confirmed pneumonia within 3 years prior to first vaccination. * 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). * Current or history of Parkinson disease, Alzheimer disease, stroke, dementia or any serious neurologic or mental disorders. * All malignancies (excluding non-melanic skin cancer) and lymphoproliferative disorders diagnosed or treated actively during the past 5 years. * Subjects with documented anaemia or iron-deficiency. * Chronic administration (defined as more than 14 days) of immunosuppressants or other immune-modifying drugs within 3 months prior to the first vaccine dose. * Planned administration/ administration of a vaccine not foreseen by the study protocol within 2 weeks of the first dose of vaccine(s) with the exception of a Flu vaccine which can be administered at least 1 week preceding the first dose of vaccine(s) or 1 month after the first dose of the vaccine(s). * 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. * Administration of immunoglobulins and/or any blood products within three months preceding the first dose of study vaccine or planned administration during the study period. * History of administration of an experimental/licensed vaccine containing MPL or QS21. * History of chronic alcohol consumption and/or drug abuse.