Immunogenicity and Safety Study of GSK Biologicals' Herpes Zoster Vaccine GSK1437173A When Co-administered With Prevenar13 in Adults Aged 50 Years and Older

The purpose of this study is to assess immunogenicity and safety of GSK Biologicals' HZ vaccine when its first dose is co-administered with a pneumococcal polysaccharide conjugate vaccine (Prevenar13) in adults aged ≥50 YOA, as compared to the control group where the two HZ/su doses are administered subsequent to Prevenar13.

Following the initial approval of the GlaxoSmithKline (GSK) Biologicals' HZ/su vaccine, the protocol was amended to indicate that the trademark is Shingrix. In addition, the term "candidate" vaccine has been replaced by "study" vaccine throughout the protocol.

Eligibility Criteria:
Inclusion Criteria:

* Subjects who, in the opinion of the investigator, can and will comply with the requirements of the protocol.
* Written informed consent obtained from the subject prior to performance of any study specific procedure.
* A male or female, aged ≥50 YOA at the time of the first vaccination with the study vaccine(s).
* Female subjects of non-childbearing potential may be enrolled in the study.
* Female subjects of childbearing potential may be enrolled in the study, if the subject:

  * has practiced adequate contraception for 30 days prior to vaccination, and
  * has a negative pregnancy test on the day of vaccination, and
  * has agreed to continue adequate contraception during the entire treatment period and for 2 months after completion of the vaccination series.

Exclusion Criteria:

* Use of any investigational or non-registered product other than the study vaccines during the period starting 30 days before the first dose of study vaccines (Day -30 to Day 1), or planned use during the study period.
* Any medical condition that in the judgment of the investigator would make intramuscular (IM) injection unsafe.
* Use or anticipated use of immunosuppressants or other immune-modifying drugs during the period starting six months prior to study start and during the whole study period. This includes chronic administration of corticosteroids (\>14 consecutive days of prednisone at a dose of ≥20 mg/day \[or equivalent\]), long-acting immune modifying agents or immunosuppressive/cytotoxic therapy. Inhaled, topical and intra-articular corticosteroids are allowed.
* Administration or planned administration of a vaccine not foreseen by the study protocol in the period starting 30 days before the first dose and ending 30 days after the last dose of study vaccine administration. This includes any type of vaccine such as (but not limited to) live, inactivated and subunit vaccines.
* 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 and/or planned administration of an HZ or VZV vaccine other than the study vaccine during the study period.
* History of HZ.
* History of documented pneumococcal infection within 5 previous years.
* Prior receipt of any pneumococcal vaccine or planned use during the study period, other than the study vaccines.
* Any confirmed or suspected immunosuppressive or immunodeficient condition resulting from disease or immunosuppressive/cytotoxic therapy.
* 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 enrollment.

  * Fever is defined as temperature ≥ 38.0°C/100.4°F. The preferred location for measuring temperature in this study will be the oral cavity.
  * Subjects with a minor illness without fever may, be enrolled at the discretion of the investigator.
* Administration of immunoglobulins and/or any blood products during the period starting 3 months before 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 before 2 months after the last dose of study vaccine.
* Any person with cerebrospinal fluid (CSF) leaks, cochlear implants, chronic renal failure, nephrotic syndrome and functional or anatomic asplenia.
* Any medical condition that in the judgment of the investigator would prevent the subject from participating in the study.