Study to Evaluate Immunogenicity and Safety of GlaxoSmithKline (GSK) Biologicals' Quadrivalent Influenza Vaccine GSK2282512A When Administered to Children From 6 to 35 Months of Age

A seroconverted subject was defined as a vaccinated subject with either a pre-vaccination titer less than (\<) 1:10 and a post-vaccination titer greater than or equal to (≥) 1:40, or a pre-vaccination titer ≥ 1:10 and at least a 4-fold increase in post-vaccination titer. The vaccine strains assessed were Flu A/California/7/2009 (H1N1), Flu A/Texas/50/2012 (H3N2), Flu B/Massachusetts/2/2012 (Yamagata), Flu B/Brisbane/60/2008 (Victoria). This outcome concerns solely subjects in the FluLaval Quadrivalent Group. Vaccine primed subjects are subjects who had received a total of 2 or more doses of seasonal influenza vaccine since 01 July 2010. Vaccine unprimed subjects are subjects who had never received any seasonal influenza vaccine or had received only one dose of seasonal influenza vaccine since 01 July 2010.

Time frame: 28 days after the last vaccine dose (at Day 28 for primed subjects and at Day 56 for unprimed subjects)

Population: Analysis was performed on the According-to-Protocol (ATP) cohort for immunogenicity which included all evaluable subjects for whom data concerning immunogenicity outcome measures were available and subjects for whom assay results were available for antibodies against at least one study vaccine antigen component after vaccination.

Duration was defined as number of days with any grade of local and general symptoms. Vaccine primed subjects are subjects who had received a total of 2 or more doses of seasonal influenza vaccine since 01 July 2010. Vaccine unprimed subjects are subjects who had never received any seasonal influenza vaccine or had received only one dose of seasonal influenza vaccine since 01 July 2010.

Time frame: During a 7-day follow-up period (i.e. day of vaccination and six subsequent days) after each vaccination

Population: Analysis was performed on the Total Vaccinated cohort, which included all subjects with vaccine administration documented and for whom safety data were available.

HI antibody titres were expressed as Geometric mean titers (GMTs). The vaccine strains assessed were Flu A/California/7/2009 (H1N1), Flu A/Texas/50/2012 (H3N2), Flu B/Massachusetts/2/2012 (Yamagata), Flu B/Brisbane/60/2008 (Victoria). Vaccine primed subjects are subjects who had received a total of 2 or more doses of seasonal influenza vaccine since 01 July 2010. Vaccine unprimed subjects are subjects who had never received any seasonal influenza vaccine or had received only one dose of seasonal influenza vaccine since 01 July 2010.

Time frame: On Day 0 and 28 days after the last vaccine (Day 28 and Day 56 for primed and unprimed subjects respectively)

Population: Analysis was performed on the ATP cohort for immunogenicity which included all evaluable subjects for whom data concerning immunogenicity outcome measures were available and subjects for whom assay results were available for antibodies against at least one study vaccine antigen component after vaccination.

MGI was defined as the fold increase in serum haemagglutination inhibition (HI) GMTs post-vaccination compared to pre-vaccination (Day 0). The vaccine strains assessed were Flu A/California/7/2009 (H1N1), Flu A/Texas/50/2012 (H3N2), Flu B/Massachusetts/2/2012 (Yamagata), Flu B/Brisbane/60/2008 (Victoria). Vaccine primed subjects are subjects who had received a total of 2 or more doses of seasonal influenza vaccine since 01 July 2010. Vaccine unprimed subjects are subjects who had never received any seasonal influenza vaccine or had received only one dose of seasonal influenza vaccine since 01 July 2010.

Time frame: 28 days after the last vaccine dose (at Day 28 for primed subjects and at Day 56 for unprimed subjects)

Population: Analysis was performed on the ATP cohort for immunogenicity which included all evaluable subjects for whom data concerning immunogenicity outcome measures were available and subjects for whom assay results were available for antibodies against at least one study vaccine antigen component after vaccination.

A seroconverted subject was defined as a vaccinated subject with either a pre-vaccination titer less than (\<) 1:10 and a post-vaccination titer greater than or equal to (≥) 1:40, or a pre-vaccination titer ≥ 1:10 and at least a 4-fold increase in post-vaccination titer. The vaccine strains assessed were Flu A/California/7/2009 (H1N1), Flu A/Texas/50/2012 (H3N2), Flu B/Massachusetts/2/2012 (Yamagata), Flu B/Brisbane/60/2008 (Victoria). This outcome concerns solely subjects in the Fluzone Group. Vaccine primed subjects are subjects who had received a total of 2 or more doses of seasonal influenza vaccine since 01 July 2010. Vaccine unprimed subjects are subjects who had never received any seasonal influenza vaccine or had received only one dose of seasonal influenza vaccine since 01 July 2010.

Time frame: 28 days after the last vaccine dose (at Day 28 for primed subjects and at Day 56 for unprimed subjects)

Population: Analysis was performed on the ATP cohort for immunogenicity which included all evaluable subjects for whom data concerning immunogenicity outcome measures were available and subjects for whom assay results were available for antibodies against at least one study vaccine antigen component after vaccination.

Solicited local symptoms assessed were pain, redness and swelling. Any was defined as occurrence of the specified solicited local symptom regardless of its intensity. Grade 3 pain was defined as pain that made the subject cry when limb was moved/spontaneously painful. Grade 3 swelling was greater than 100 millimeters (mm) i.e. \>100mm. Vaccine primed subjects are subjects who had received a total of 2 or more doses of seasonal influenza vaccine since 01 July 2010. Vaccine unprimed subjects are subjects who had never received any seasonal influenza vaccine or had received only one dose of seasonal influenza vaccine since 01 July 2010.

Time frame: During a 7-day follow-up period (i.e. day of vaccination and six subsequent days) after each vaccination

Population: Analysis was performed on the Total Vaccinated cohort, which included all subjects with vaccine administration documented and for whom safety data were available.

A serious adverse event was defined as any untoward medical occurrence that: resulted in death, was life threatening, required hospitalization or prolongation of hospitalization, resulted in disability/incapacity or was a congenital anomaly/birth defect in the offspring of a study subject. Any was defined as occurrence of any symptom regardless of intensity grade or relation to vaccination and related was an event assessed by the investigator as causally related to the study vaccination. Vaccine primed subjects are subjects who had received a total of 2 or more doses of seasonal influenza vaccine since 01 July 2010. Vaccine unprimed subjects are subjects who had never received any seasonal influenza vaccine or had received only one dose of seasonal influenza vaccine since 01 July 2010.

Time frame: During the entire study period (Day 0 - Day 180)

Population: Analysis was performed on the Total Vaccinated cohort, which included all subjects with vaccine administration documented and for whom safety data were available.

Any fever was defined as any fever ≥38.0 degrees Celsius (°C) irrespective of intensity and relationship to vaccination. Related was defined as symptoms assessed by the investigator to have a causal relationship to vaccination. Grade 3 fever was defined as fever ≥39.0 °C. Vaccine primed subjects are subjects who had received a total of 2 or more doses of seasonal influenza vaccine since 01 July 2010. Vaccine unprimed subjects are subjects who had never received any seasonal influenza vaccine or had received only one dose of seasonal influenza vaccine since 01 July 2010.

Time frame: During a 4-day follow-up period (i.e. day of vaccination and 3 subsequent days) after each vaccination

Population: Analysis was performed on the Total Vaccinated cohort, which included all subjects with vaccine administration documented and for whom safety data were available.

Solicited general symptoms assessed were drowsiness, irritability/fussiness and loss of appetite. Any was defined as any solicited general symptom reported irrespective of intensity and relationship to vaccination. Related was defined as symptoms assessed by the investigator to have a causal relationship to vaccination. Grade 3 irritability/fussiness was defined as crying that could not be comforted/prevented normal activity. Grade 3 loss of appetite was defined as not eating at all. Grade 3 drowsiness was defined as drowsiness that prevented normal activity.Grade 3 fever was defined as axillary temperature above 39.0°C. Vaccine primed subjects are subjects who had received a total of 2 or more doses of seasonal influenza vaccine since 01 July 2010. Vaccine unprimed subjects are subjects who had never received any seasonal influenza vaccine or had received only one dose of seasonal influenza vaccine since 01 July 2010.

Time frame: During a 7-day follow-up period (i.e. day of vaccination and six subsequent days) after each vaccination

Population: Analysis was performed on the Total Vaccinated cohort, which included all subjects with vaccine administration documented and for whom safety data were available.

An unsolicited AE was defined as an untoward medical occurrence in a patient or clinical investigation subject, temporally associated with 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 occurrence of any unsolicited symptom regardless of intensity grade or relation to vaccination. Grade 3 was an event that prevented normal activities and related was defined as an unsolicited AE assessed by the investigator to be causally related to the study vaccination Vaccine primed subjects are subjects who had received a total of 2 or more doses of seasonal influenza vaccine since 01 July 2010. Vaccine unprimed subjects are subjects who had never received any seasonal influenza vaccine or had received only one dose of seasonal influenza vaccine since 01 July 2010

Time frame: During a 28-day follow-up period (i.e. day of vaccination and 27 subsequent days) after each vaccination

Population: Analysis was performed on the Total Vaccinated cohort, which included all subjects with vaccine administration documented and for whom safety data were available.

MAEs were defined as adverse events with medically-attended visits that were not routine visits for physical examination or vaccination, such as visits for hospitalization, an emergency room visit, or an otherwise unscheduled visit to or from medical personnel (medical doctor) for any reason. Any was defined as any occurrence of MAE(s). Related was defined as a MAE assessed by the investigator to be causally related to the study vaccination. Vaccine primed subjects are subjects who had received a total of 2 or more doses of seasonal influenza vaccine since 01 July 2010. Vaccine unprimed subjects are subjects who had never received any seasonal influenza vaccine or had received only one dose of seasonal influenza vaccine since 01 July 2010.

Time frame: During the entire study period (Day 0 to Day 180)

Population: Analysis was performed on the Total Vaccinated cohort, which included all subjects with vaccine administration documented and for whom safety data were available.

pIMDs were defined as a subset of adverse events that included both clearly autoimmune diseases and also other inflammatory and/or neurologic disorders which might or might not have an autoimmune aetiology. Any pIMD was defined as at least one pIMD experienced by the study subject. Related pIMD was defined as a pIMD assessed by the investigator to be causally related to the study vaccination. Vaccine primed subjects are subjects who had received a total of 2 or more doses of seasonal influenza vaccine since 01 July 2010. Vaccine unprimed subjects are subjects who had never received any seasonal influenza vaccine or had received only one dose of seasonal influenza vaccine since 01 July 2010.

Time frame: During the entire study period (Day 0 to Day 180)

Population: Analysis was performed on the Total Vaccinated cohort, which included all subjects with vaccine administration documented and for whom safety data were available.

A seroprotected subject was defined as a vaccinated subject with a serum HI titer greater than or equal to (≥) 1:40 that usually is accepted as indicating protection in adults. The vaccine strains assessed were Flu A/California/7/2009 (H1N1), Flu A/Texas/50/2012 (H3N2), Flu B/Massachusetts/2/2012 (Yamagata), Flu B/Brisbane/60/2008 (Victoria). Vaccine primed subjects are subjects who had received a total of 2 or more doses of seasonal influenza vaccine since 01 July 2010. Vaccine unprimed subjects are subjects who had never received any seasonal influenza vaccine or had received only one dose of seasonal influenza vaccine since 01 July 2010.

Time frame: At Day 0 (for all subjects) and Day 28 after last vaccine dose (Day 28 for primed subjects and Day 56 for unprimed subjects)

Population: Analysis was performed on the ATP cohort for immunogenicity which included all evaluable subjects for whom data concerning immunogenicity outcome measures were available and subjects for whom assay results were available for antibodies against at least one study vaccine antigen component after vaccination.