Evaluation of the immunogenicity and safety of GlaxoSmithKline (GSK) Biologicals’ Quadrivalent Influenza Vaccine Influsplit™ Tetra (Fluarix™ Tetra) (GSK2321138A) when co-administered with Pneumovax™ 23 in adults 50 years of age and older

Subjects who, in the opinion of the investigator, can and will comply with the requirements of the protocol (e.g. completion of the diary cards, return for follow-up visits).

• A male or female aged 50 years or above at the time of the first vaccination at risk for complications from influenza and/or pneumococcal infections, meeting their respective countries’ recommendations for vaccination against influenza and pneumococcal disease.

At risk subjects include adults with chronic respiratory, heart, kidney, liver or neurological disease; human immunodeficiency virus (HIV) disease on combination antiretroviral therapy (cART) with cluster of differentiation 4 (CD4) T-cell counts greater than 350 cells/mm3; sickle cell disease or coeliac syndrome that may lead to splenic dysfunction (all other asplenics are excluded). The decision to enrol should be based on the investigators clinical judgement.

• Written informed consent obtained from the subject.
• Female subjects of non-childbearing potential may be enrolled in the study.

Non-childbearing potential is defined as pre-menarche, current tubal ligation, hysterectomy, ovariectomy or post-menopause.

• Female subjects of childbearing potential may be enrolled in the study, if the subject:

Use of any investigational or non-registered product other than the study vaccines within 30 days preceding the first dose of study vaccine, or planned use during the study period.

• Chronic administration (defined as more than 14 days in total) of immunosuppressants or other immune-modifying drugs within six months prior to the first vaccine dose. Inhaled, topical and low-dose intra-articular steroids are allowed.
• Planned administration/administration of a vaccine not foreseen by the study protocol within the period starting 30 days before the first dose and 30 days after the last dose of vaccine.
• Administration of such a vaccine has to be documented in the "Concomitant vaccination" of the electronic Case Report Form (eCRF).
• Administration of long-acting immune-modifying drugs/treatment within six months prior to the first vaccine dose or expected administration at any time during the study period. These immunosuppressant drugs/treatment/Biologics include:

Any immunosuppressive treatment which in the opinion of the investigator will not allow an adequate immune response. Inhaled, topical and low-dose intra-articular steroids are allowed.

• 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 vaccine/product.
• Previous vaccination with a pneumococcal vaccine within the last five years.
• Previous vaccination with an influenza vaccine within the last six months.
• Any confirmed or suspected immunosuppressive or immunodeficient condition, based on medical history and physical examination. HIV infected subjects on cART with CD4 T-cell counts above 350 cells/mm3 can be enrolled.
• History of any reaction or hypersensitivity likely to be exacerbated by any component of the vaccines.
• Acute disease and/or fever at the time of enrolment.

Subjects with a minor illness (such as mild diarrhoea, mild upper respiratory infection) without fever [≥ 38.0°C (100.4°F)] may be enrolled at the discretion of the investigator.

• Administration of immunoglobulins and/or any blood products within the three months preceding the first dose of study vaccine or planned administration during the study period.
• Pregnant or lactating female.
• Female planning to become pregnant or planning to discontinue contraceptive precautions.
• Any condition which, in the opinion of the investigator, prevents the subject from participating in the study or would make intramuscular (IM) injection unsafe.
• Asplenia or dysfunction of the spleen. This excludes homozygous sickle cell disease or coeliac syndrome that may lead to splenic dysfunction.
• Acute clinically significant (i.e. a medically significant change from baseline condition in the past 30 days) pulmonary, cardiovascular, hepatic or renal functional abnormality, as determined by physical examination or laboratory screening tests.
• History of chronic alcohol consumption and/or drug abuse.
• History of Guillain-Barré syndrome.
• A history of anaphylaxis following ANY vaccination.