Study to Evaluate the Immunogenicity and Safety of GlaxoSmithKline (GSK) Biologicals' Herpes Zoster Vaccine GSK1437173A When Co-administered With GSK Biologicals' Seasonal Influenza Vaccine GSK2321138A in Adults Aged 50 Years and Older

The vaccine response(VRR) for anti-gE humoral immunogenicity, as determined by enzyme-linked immunosorbent assay (ELISA),was assessed only in subjects from the GSK1437173A + GSK2321138A Group. The VRR for anti-gE was defined as the percentage of subjects who had at least: a 4-fold increase in the post-dose 2 anti-gE antibody concentration as compared to the pre-vaccination anti-gE antibody concentration, for subjects who were seropositive at baseline (cut-off ≥ 97 mIU/ml), or, a 4-fold increase in the post dose 2 anti-gE antibody concentrations as compared to the anti-gE antibodies cut-off value for seropositivity, for subjects who were seronegative at baseline (cut-off < 97 mIU/ml).

The vaccine response(VRR) for anti-gE humoral immunogenicity, as determined by enzyme-linked immunosorbent assay (ELISA),was assessed only in subjects from the GSK1437173A + GSK2321138A Group. The VRR for anti-gE was defined as the percentage of subjects who had at least:

a 4-fold increase in the post-dose 2 anti-gE antibody concentration as compared to the pre-vaccination anti-gE antibody concentration, for subjects who were seropositive at baseline (cut-off ≥ 97 mIU/ml), or, a 4-fold increase in the post dose 2 anti-gE antibody concentrations as compared to the anti-gE antibodies cut-off value for seropositivity, for subjects who were seronegative at baseline (cut-off < 97 mIU/ml).Criterion used: the objective was met if the Lower Limit (LL) of the 95% confidence interval (CI) of the VRR for anti-gE antibody concentrations was at least 60%.

Geometric means (GMs) of post-vaccination concentrations (Month 3 for GSK1437173A + GSK2321138A group and Month 5 for Control group) was calculated conditionally to the means of the pre-vaccination log-transformed concentrations for anti-gE (Month 0 for GSK1437173A + GSK2321138A group and Month 2 for Control group). Adjusted Least Squares (LS) means and difference of LS means between the groups were calculated together with 2-sided 95% CIs and back-transformed to the original units to provide GMCs.

For each strain included in the FLU-D-QIV vaccine, an ANOVA model was used to analyze post-vaccination log-transformed titers. The fixed-effect model included the minimization variable (age cohorts) and the treatment as fixed effect. The pre-vaccination log-transformed concentrations were included as continuous covariate. Geometric Means (GM) of post-vaccination titers (Day 21) were calculated conditionally to the means of the pre-vaccination log-transformed titers (Month 0) for each strain.

Adjusted GMTs (GMTs adjusted for baseline titers) and Adjusted GMT ratios were calculated together with 2-sided 95% CIs.

FLU HI antibodies were assessed in four strains: Flu A/California/7/2009 H1N1, Flu A/Texas/50/2012 H3N2, Flu B/Brisbane/60/2008 Victoria and Flu B/Massachusetts (Massach)/2/2012 Yamagata (Yama). Cut-off titer for seropositivity was 1:10.

Seroprotection rate is defined as the percentage of vaccines with a serum HI titer ≥1:40 that usually was accepted as indicating protection. FLU HI antibodies were assessed in four strains: Flu A/California/7/2009 H1N1, Flu A/Texas/50/2012 H3N2, Flu B/Brisbane/60/2008 Victoria (Vic) and Flu B/Massachusetts(Massach)/2/2012 Yamagata (Yama).

HI antibody titres against the four influenza vaccine strains Flu A/California/7/2009, Flu A/Texas/50/2012, Flu B/Brisbane/60/2008 Victoria (Vic) and Flu B/Massachusetts (Massach)/2/2012 Yamagata (Yamma) were expressed as geometric mean titers (GMTs).

The number of seroconverted subjects was assessed in terms of HI antibodies against the four influenza vaccine strains Flu A/California/7/2009, Flu A/Texas/50/2012, Flu B/Brisbane/60/2008 Victoria and Flu B/Massachusetts/2/2012 Yamagata.

The geometric mean ratio for Flu HI antibodies against the four influenza vaccine strains Flu A/California/7/2009, Flu A/Texas/50/2012, Flu B/Brisbane/60/2008 Victoria and Flu B/Massachusetts/2/2012 Yamagata was defined as the geometric mean of the within subject ratios of the post-vaccination reciprocal HI titer to the Day 0 reciprocal HI titer.

Assessed solicited local symptoms were pain, redness and swelling. Any = occurrence of the symptom regardless of intensity grade. Grade 3 (G3) pain = pain that prevented normal activity. Grade 3 (G3) redness/swelling = redness/swelling spreading beyond 100 millimeters (mm) of injection site. Relationship analysis was not performed.

Assessed solicited local symptoms were pain, redness and swelling. Any = occurrence of the symptom regardless of intensity grade. Grade 3 pain = pain that prevented normal activity. Grade 3 redness/swelling = redness/swelling spreading beyond 100 millimeters (mm) of injection site. Relationship analysis was not performed.

Assessed solicited general symptoms were arthralgia, fatigue, gastrointestinal symptoms, headache, myalgia, shivering and fever [defined as axillary temperature equal to or above 37.5 degrees Celsius (°C)]. Any = occurrence of the symptom regardless of intensity grade. Grade 3 symptom = symptom that prevented normal activity. Grade 3 fever = fever > 39.0 °C. Related = symptom assessed by the investigator as related to the vaccination.

Assessed solicited general symptoms were arthralgia, fatigue, gastrointestinal symptoms, headache, myalgia, shivering and fever [defined as axillary temperature equal to or above 37.5 degrees Celsius (°C)]. Any = occurrence of the symptom regardless of intensity grade. Grade 3 symptom = symptom that prevented normal activity. Grade 3 fever = fever > 39.0 °C. Related = symptom assessed by the investigator as related to the vaccination.

An unsolicited AE covers any untoward medical occurrence in a clinical investigation subject temporally associated with the use of a medicinal product, whether or not considered related to the medicinal product and reported in addition to those solicited during the clinical study and any solicited symptom with onset outside the specified period of follow-up for solicited symptoms. Any was defined as the occurrence of any unsolicited AE regardless of intensity grade or relation to vaccination. Grade 3 AE = an AE which prevented normal, everyday activities. Related = AE assessed by the investigator as related to the vaccination.

Serious adverse events (SAEs) assessed include medical occurrences that result in death, are life threatening, require hospitalization or prolongation of hospitalization or result in disability/incapacity.

pIMDs are 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 aetiology.