A Study to Test GlaxoSmithKline's (GSK) Herpes Zoster (HZ) Subunit Vaccine's Long-term Immune Response in Previously Vaccinated Kidney Transplant Adults and Then to Test if 2 Additional Doses of the Vaccine Are Safe and Able to Generate an Immune Response

Anti-gE antibody concentrations were determined by enzyme-linked immunosorbent assay (ELISA) and expressed as geometric mean concentrations (GMCs) in milli-international units per milliliter (mIU/mL).

Anti-gE antibody concentrations were determined by ELISA and expressed as GMCs in mIU/mL.

Frequency of gE-specific CD4 (2+) T-cells expressing two or more activation markers (from among interferon gamma [IFN-γ], interleukin-2 [IL-2], tumour necrosis factor alpha [TNF-α] and CD40 Ligand [CD40L]) was determined by intracellular cytokine staining (ICS) as measured by cytokine flow cytometry (CFC) and expressed in CD4(2+) T-cells per million cells [CD4(2+) T-cells/million cells].

SAEs assessed included any untoward medical occurrence that resulted in death, was life-threatening, required hospitalization or prolongation of existing hospitalization or resulted in disability/incapacity or was a congenital anomaly/birth defect in the offspring of a study participant. SAEs related to primary vaccination in ZOSTER-041 study were assessed by the investigator.

A suspected HZ case was defined as a new unilateral rash accompanied by pain (broadly defined to include allodynia, pruritus or other sensations) without alternative diagnosis.

A confirmed HZ case was diagnosed by an algorithm that included Polymerase Chain Reaction (PCR) and the HZ Ascertainment Committee (HZAC) determination.

A confirmed HZ case was diagnosed by an algorithm that included Polymerase Chain Reaction (PCR) and the HZ Ascertainment Committee (HZAC) determination.

The number of participants with biopsy for clinical indication (suspected) or surveillance protocol that was not biopsy-proven rejection and with biopsy-proven allograft rejections are reported. Biopsy-proven allograft rejections are defined as adverse events of specific interest (AESIs).

Biopsy-proven allograft rejection is defined as an adverse event of specific interest (AESI).

Declining allograft function (allograft dysfunction) was assessed through all clinically obtained serum creatinine values from 2 months prior to an episode of biopsy-proven rejection and up to 2 months after rejection resolution and cessation of therapeutic immunosuppressive therapy. Allograft dysfunction is defined as having a fold increase in serum creatinine of 1.2 greater from the reference timepoint (2 months prior to an episode of biopsy-proven rejection).

Declining allograft function was assessed through all clinically obtained serum creatinine values from 2 months prior to an episode of HZ and up to 2 months after HZ rash resolution. Allograft dysfunction is defined as having a fold increase in serum creatinine of 1.2 greater from the reference timepoint (2 months prior to an episode of HZ).

Frequency of gE-specific CD4 (2+) T-cells expressing two or more activation markers (from among IFN-γ, IL-2, TNF-α and CD40L) was determined by ICS as measured by CFC and expressed in CD4(2+) T-cells/million cells.

Persistence of humoral immunity after the revaccination course was evaluated in terms of anti-gE antibody concentrations. Anti-gE antibody concentrations were determined by ELISA and expressed as GMCs in mIU/mL.

Frequency of gE-specific CD4 (2+) T-cells expressing two or more activation markers (from among IFN-γ, IL-2, TNF-α and CD40L) was determined by ICS as measured by CFC and expressed in CD4(2+) T-cells/million cells.

Assessed solicited administration site events included erythema, pain and swelling at injection site. Any = occurrence of the event regardless of intensity grade. Any erythema/swelling at injection site = erythema/swelling at injection site with a diameter larger than (>) 20 millimeters (mm). Grade 3 pain = significant pain at rest, which prevented normal, everyday activities. Grade 3 erythema/swelling at injection site = erythema/swelling at injection site with a diameter >100 mm.

Duration is the number of days in which a participant experienced the solicited administration site event within the 7-day solicited follow-up period. Assessed solicited administration site events included erythema, pain and swelling at injection site.

Assessed solicited systemic events included fatigue, gastrointestinal symptoms (including nausea, vomiting, diarrhea and/or abdominal pain), headache, myalgia, shivering and fever [temperature higher than or equal (>=) to 38.0 degrees Celsius (°C)/100.4 degrees Fahrenheit (°F)]. Any AE = occurrence of the event regardless of intensity grade. Grade 3 fatigue, gastrointestinal symptoms, headache, myalgia, shivering = event that prevented normal, everyday activities. Grade 3 fever = temperature higher (>) than 39°C/102.2°F. Related fatigue, gastrointestinal symptoms, headache, myalgia, shivering, fever = event assessed by the investigator as related to the revaccination. The preferred route for measuring temperature in this study was oral.

Duration is the number of days in which a participant experienced the solicited systemic event within the 7-day solicited follow-up period. Assessed solicited systemic events included fatigue, gastrointestinal symptoms (including nausea, vomiting, diarrhea and/or abdominal pain), headache, myalgia, shivering and fever.

An unsolicited AE was defined as any AE reported in addition to those solicited during the clinical study. Also, any 'solicited' symptom with onset outside the specified period of follow-up for solicited symptoms was reported as an unsolicited AE. Any = occurrence of the event regardless of intensity grade or relation to revaccination. Grade 3 = event that prevented normal, everyday activities. Related = event assessed by the investigator as related to revaccination.

SAEs assessed included any untoward medical occurrence that resulted in death, was life-threatening, required hospitalization or prolongation of existing hospitalization or resulted in disability/incapacity or was a congenital anomaly/birth defect in the offspring of a study participant. Any = occurrence of the SAE regardless of intensity grade or relation to revaccination. Fatal = SAE resulting in the death of the participant.

SAEs assessed included any untoward medical occurrence that resulted in death, was life-threatening, required hospitalization or prolongation of existing hospitalization or resulted in disability/incapacity or was a congenital anomaly/birth defect in the offspring of a study participant. Related = SAE assessed by the investigator as related to revaccination. Related-fatal = SAE resulting in the death of the participant assessed by the investigator as related to revaccination.

Biopsy-proven allograft rejection is defined as an adverse event of special interest (AESI) and is recorded in serious adverse event (SAE) screens, irrespective of the seriousness of the event. Related biopsy proven allograft rejections = biopsy-proven allograft rejections assessed by the investigator as related to revaccination.

pIMDs are defined as a subset of AEs that include autoimmune diseases and other inflammatory and/or neurologic disorders of interest which may or may not have an autoimmune etiology. Any = occurrence of the pIMD regardless of intensity grade or relation to revaccination. Related = pIMDs assessed by the investigator as related to revaccination.

A confirmed HZ case was diagnosed by an algorithm that included Polymerase Chain Reaction (PCR) and the HZ Ascertainment Committee (HZAC) determination.

Declining allograft function was assessed through all clinically obtained serum creatinine values from 3 months before the first revaccination dose until 3 months after the last revaccination dose. Allograft dysfunction is defined as having a fold increase in serum creatinine of 1.2 greater from the reference timepoint (3 months prior to revaccination).

Declining allograft function was assessed through all clinically obtained serum creatinine values from 2 months prior to an episode of biopsy-proven rejection and up to 2 months after rejection resolution and cessation of therapeutic immunosuppressive therapy. Allograft dysfunction is defined as having a fold increase in serum creatinine of 1.2 greater from the reference timepoint (2 months prior to an episode of biopsy-proven rejection).

Declining allograft function was assessed through all clinically obtained serum creatinine values from 2 months prior to an episode of HZ and up to 2 months after HZ resolution. Allograft dysfunction is defined as having a fold increase in serum creatinine of 1.2 greater from the reference timepoint (2 months prior to an episode of HZ).