Study to Evaluate Efficacy, Safety, and Immunogenicity of GlaxoSmithKline (GSK) Biologicals' Herpes Zoster Vaccine GSK1437173A

Inclusion Criteria:

Study entry (enrollment) occurs at the Pre-vaccination visit.

- Subjects who the investigator believes can and will comply with the requirements of
the protocol.

- Written informed consent obtained from the subject.

- A male or female aged 18 years or older at the time of study entry.

- Has undergone or will undergo autologous HCT within 50-70 days prior to the first
vaccination with the study vaccine/placebo, and there are no plans for additional
HCTs.

- Female subjects of non-childbearing potential may be enrolled in the study. For this
study population, non-childbearing potential is defined as current tubal ligation,
hysterectomy, ovariectomy or post-menopause.

OR Female subjects of childbearing potential may be enrolled in the study, if the subject
has practiced adequate contraception for 30 days prior to vaccination with the study
vaccine/placebo, 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 12
months after completion of the vaccination series (i.e., until Month 13).

Exclusion Criteria:

- Use of any investigational or non-registered product other than the study vaccine
within 30 days preceding the first dose of study vaccine/placebo, or planned use
during the study period. However, the investigational use of a registered or
non-registered product to treat the subject's underlying disease for which the HCT was
undertaken, or a complication of the underlying disease, is allowed.

- Previous vaccination against HZ or varicella within the 12 months preceding the first
dose of study vaccine/placebo.

- Planned administration during the study of a HZ vaccine other than the study vaccine.

- Occurrence of a varicella or HZ episode by clinical history within the 12 months
preceding the first dose of study vaccine/placebo.

- History of allergic disease or reactions likely to be exacerbated by any component of
the vaccine or study material and equipment.

- Prophylactic antiviral therapy with activity against Varicella Zoster Virus (VZV)
expected to last more than 6 months after transplantation.

- Administration and/or planned administration of a vaccine not foreseen by the study
protocol between HCT and 30 days after the last dose of study vaccine/placebo.
However, licensed non-replicating vaccines may be administered up to 8 days prior to
dose 1and/or 2, and/or at least 14 days after any dose of study vaccine/placebo.

- HIV infection by clinical history.

- Pregnant or lactating female.

- Female planning to become pregnant or planning to discontinue contraceptive
precautions (if of childbearing potential) before Month 13 (i.e., one year after the
last dose of study vaccine/placebo).