Subjects aged at enrolment between 3 and 36 months, 36 months excluded, received 2 doses of saline placebo at Days 0 and 21. The saline placebo was administered intramuscularly. For children aged up to 12 months, 12 months excluded (< 12 months), Dose 1 was administered in the left anterolateral thigh and Dose 2 in the right anterolateral thigh. For children older than (>=) 12 months, Dose 1 was administered in the deltoid region of the non-dominant arm (or left arm if dominance was not yet identified) and Dose 2 in the deltoid region of the dominant arm (or right arm).

Subjects aged at enrolment between 3 and 9 years, 9 years excluded, received 2 doses of saline placebo at Days 0 and 21. The saline placebo was administered intramuscularly, Dose 1 in the deltoid region of the non-dominant arm (or left arm if dominance was not yet identified) and Dose 2 in the deltoid region of the dominant arm (or right arm).

Subjects aged at enrolment between 9 and 18 years, 18 years excluded, received 2 doses of saline placebo at Days 0 and 21. The saline placebo was administered intramuscularly, Dose 1 in the deltoid region of the non-dominant arm (or left arm if dominance was not yet identified) and Dose 2 in the deltoid region of the dominant arm (or right arm).

Subjects in this group were those who were administered the saline placebo solution in the Blinded Phase of the study (either in the Placebo 6-<36M, Placebo 3-<9Y or Placebo 9-<18Y Group). These were subjects aged at enrolment between 6 months and 18 years, 18 years excluded, who had received 2 doses of saline placebo at Days 0 and 21 in the Blinded Phase of the study, as per described in the descriptions of the Placebo 6-<36M, Placebo 3-<9Y and Placebo 9-<18Y groups. After consenting to participating to the Unblinded Phase of the study, these subjects received in addition 2 doses of Influenza A (H5N1) Virus monovalent vaccine at Days 385 (Day U0) and Day 385 + 21 days (Day U21). Influenza A (H5N1) Virus monovalent vaccine was administered intramuscularly. Dose 1 of was administered in the deltoid region of the non-dominant arm and Dose 2 in the deltoid region of the dominant arm.

All subjects will receive 2 doses administered as an intramuscular (IM) injection.

A subject seroconverted for HI antibodies against the H5N1 A/Indonesia virus strain (A/INDO) was defined as a vaccinee with either a pre-vaccination titer less than (<) 1:10 and a post-vaccination titer higher than or equal to (>=) 1:40, or with a pre-vaccination titer >= 1:10 and at least a 4-fold increase in post-vaccination titer.

As the analyses were performed and disclosed stepwise - i.e. as soon as a study phase was completed - several releases of the CTRS (result summaries) were published. To generate an integrated Clinical Study Report, one set of domain datasets covering all analyses was used and the Adapted ATP cohort for immunogenicity has been defined. As a consequence, some of the data previously disclosed and based on ATP cohort for immunogenicity at Day 42, Day 182 and Day 385 have been replaced in this summary with data generated with the Adapted ATP cohort for immunogenicity.

GMI also known as the seroconversion factor (SCF) or geometric mean fold rise (GMFR) was defined as the geometric mean of the within-subject ratios of the post-vaccination reciprocal HI titre to the pre-vaccination reciprocal HI titre for the vaccine virus.

HI antibody titers against the H5N1 A/Indonesia virus strain (A/INDO) were expressed as geometric mean titers (GMTs). The cut-off of the assay was the seropositivity cut-off of higher than or equal to (>=) 1:10.

Adapted ATP cohort for immunogenicity included all evaluable subjects for which Day 21 and Day 42 data were obtained from the ATP cohort for immunogenicity at Day 42; Day 182 data were obtained from the ATP cohort for immunogenicity at Day 182, and Day 385 data were obtained from the ATP cohort for immunogenicity at Day 385.

A seroprotected subject against the a/Indonesia/5/2005 (A/INDO) virus strain was defined as a subject with H5N1 reciprocal haemagglutination inhibition (HI) antibody titers greater than or equal to (>=) the seroprotection cut-off of 1:40.

As the analyses were performed and disclosed stepwise - i.e. as soon as a study phase was completed - several releases of the CTRS (result summaries) were published. To generate an integrated Clinical Study Report, one set of domain datasets covering all analyses was used and the Adapted ATP cohort for immunogenicity has been defined. As a consequence, some of the data previously disclosed and based on ATP cohort for immunogenicity at Day 42, Day 182 and Day 385 have been replaced in this summary with data generated with the Adapted ATP cohort for immunogenicity.

HI antibody titers against the H5N1 A/Indonesia virus strain (A/INDO) were expressed as geometric mean titers (GMTs). The cut-off of the assay was the seropositivity cut-off of higher than or equal to (>=) 1:10.

As the analyses were performed and disclosed stepwise - i.e. as soon as a study phase was completed - several releases of the CTRS (result summaries) were published. To generate an integrated Clinical Study Report, one set of domain datasets covering all analyses was used and the Adapted ATP cohort for immunogenicity has been defined. As a consequence, some of the data previously disclosed and based on ATP cohort for immunogenicity at Day 42, Day 182 and Day 385 have been replaced in this summary with data generated with the Adapted ATP cohort for immunogenicity.

A subject seroconverted for HI antibodies against the H5N1 A/Indonesia virus strain (A/INDO) was defined as a vaccinee with either a pre-vaccination titer less than (<) 1:10 and a post-vaccination titer higher than or equal to (>=) 1:40, or with a pre-vaccination titer >= 1:10 and at least a 4-fold increase in post-vaccination titer.

GMI also known as the seroconversion factor (SCF) or geometric mean fold rise (GMFR) was defined as the geometric mean of the within-subject ratios of the post-vaccination reciprocal HI titre to the pre-vaccination reciprocal HI titre for the vaccine virus.

HI antibody titers against the H5N1 A/Indonesia virus strain (A/INDO) were expressed as geometric mean titers (GMTs). The cut-off of the assay was the seropositivity cut-off of higher than or equal to (>=) 1:10.

As the analyses were performed and disclosed stepwise - i.e. as soon as a study phase was completed - several releases of the CTRS (result summaries) were published. To generate an integrated Clinical Study Report, one set of domain datasets covering all analyses was used and the Adapted ATP cohort for immunogenicity has been defined. As a consequence, some of the data previously disclosed and based on ATP cohort for immunogenicity at Day 42, Day 182 and Day 385 have been replaced in this summary with data generated with the Adapted ATP cohort for immunogenicity.

A seroprotected subject against the a/Indonesia/5/2005 (A/INDO) virus strain was defined as a subject with H5N1 reciprocal haemagglutination inhibition (HI) antibody titers greater than or equal to (>=) the seroprotection cut-off of 1:40.

As the analyses were performed and disclosed stepwise - i.e. as soon as a study phase was completed - several releases of the CTRS (result summaries) were published. To generate an integrated Clinical Study Report, one set of domain datasets covering all analyses was used and the Adapted ATP cohort for immunogenicity has been defined. As a consequence, some of the data previously disclosed and based on ATP cohort for immunogenicity at Day 42, Day 182 and Day 385 have been replaced in this summary with data generated with the Adapted ATP cohort for immunogenicity.

A subject seroconverted for HI antibodies against the H5N1 A/Indonesia virus strain (A/INDO) was defined as a vaccinee with either a pre-vaccination titer less than (<) 1:10 and a post-vaccination titer higher than or equal to (>=) 1:40, or with a pre-vaccination titer >= 1:10 and at least a 4-fold increase in post-vaccination titer.

GMI also known as the seroconversion factor (SCF) or geometric mean fold rise (GMFR) was defined as the geometric mean of the within-subject ratios of the post-vaccination reciprocal HI titer to the pre-vaccination reciprocal HI titer for the vaccine virus.

MN HI antibody titers against the H5N1 A/Indonesia (A/INDO) and H5N1 A/Vietnam (A/VIET) virus strains were expressed as geometric mean titers (GMTs). The cut-off of the assay was the seropositivity cut-off of higher than or equal to (>=) 1:28.

VRR for MN was defined as as the incidence rate of vaccinees with a 4-fold increase in post vaccination reciprocal titer relative to Day 0.

Solicited local symptoms assessed were pain, redness and swelling. "Any" was defined as any occurrence of the specified solicited local symptom reported, regardless of intensity. Grade 3 pain was defined as pain that prevented normal activity. Grade 3 redness and swelling were defined as redness/swelling above 100 millimeter (mm).

Solicited local symptoms assessed were pain and swelling. "Any" was defined as any occurrence of the specified solicited local symptom reported, regardless of intensity. Grade 3 pain was defined as pain that prevented normal activity. Grade 3 redness and swelling were defined as redness/swelling above 100 millimeter (mm).

Solicited general symptoms assessed in subjects of less than 6 years of age were drowsiness, irritability/fussiness, loss of appetite and fever [axillary temperature (T) higher than or equal to (>=) 38.0 degrees Celsius (°C)]. "Any" was defined as any occurrence of the specified solicited general symptom reported, regardless of intensity or relationship to vaccination. Grade 3 was defined as a general symptom that prevented normal activity. Related was defined as a general symptom assessed by the investigator as causally related to the study vaccination. Any fever was defined as axillary temperature above 38.0 degrees Celsius (°C). Grade 3 fever was axillary temperature >= 39.0°C.

Solicited general symptoms assessed in subjects of less than 6 years of age were drowsiness, irritability/fussiness, loss of appetite and fever [axillary temperature (T) higher than or equal to (>=) 38.0 degrees Celsius (°C)]. "Any" was defined as any occurrence of the specified solicited general symptom reported, regardless of intensity or relationship to vaccination. Grade 3 was defined as a general symptom that prevented normal activity. Related was defined as a general symptom assessed by the investigator as causally related to the study vaccination. Any fever was defined as axillary temperature above 38.0 degrees Celsius (°C). Grade 3 fever was axillary temperature >=39.0°C.

Solicited general symptoms assessed in subjects of at least 6 years of age were fatigue, gastrointestinal symptoms, headache, joint pain at other location, muscle aches, shivering, sweating and fever [axillary temperature (T) >= 38.0 degrees Celsius (°C)]. Gastrointestinal symptoms included nausea, vomiting, diaorrhea and/or abdominal pain. "Any" was defined as any occurrence of the specified solicited general symptom reported, regardless of intensity or relationship to vaccination. Grade 3 was defined as a general symptom that prevented normal activity. Related was defined as a general symptom assessed by the investigator as causally related to the study vaccination. Grade 3 fever was axillary temperature >= 39.0°C.

Solicited general symptoms assessed in subjects of at least 6 years of age were fatigue, gastrointestinal symptoms, headache, joint pain at other location, muscle aches, shivering, sweating and fever [axillary temperature (T) >= 38.0 degrees Celsius (°C)]. Gastrointestinal symptoms included nausea, vomiting, diaorrhea and/or abdominal pain. "Any" was defined as any occurrence of the specified solicited general symptom reported, regardless of intensity or relationship to vaccination. Grade 3 was defined as a general symptom that prevented normal activity. Related was defined as a general symptom assessed by the investigator as causally related to the study vaccination. Grade 3 fever was axillary temperature >= 39.0°C.

MAEs were defined as adverse events with medically-attended visits that were not routine visits for physical examination or vaccination. Any MAE was defined as atleast 1 MAE experienced.

MAEs were defined as adverse events with medically-attended visits that were not routine visits for physical examination or vaccination. Any MAE was defined as atleast 1 MAE experienced.

Potential immune-mediated diseases (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.

Potential immune-mediated diseases (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.

Subjects were categorized according to their results at pre-vaccination (PRE), Day 42, Day 182 and Day 385 which were normal, above normal, below the normal ranges or unknown.

Subjects were categorized according to their results at pre-vaccination (PRE), Day 42, Day 182 and Day 385 which were normal, above normal, below the normal ranges or unknown.

Subjects were categorized according to their results at pre-vaccination (PRE), Day 42, Day 182 and Day 385 which were normal, above normal, below the normal ranges or unknown.

Subjects were categorized according to their results at pre-vaccination (PRE), Day 42, Day 182 and Day 385 which were normal, above normal, below the normal ranges or unknown.

Subjects were categorized according to their results at pre-vaccination (PRE), Day 42, Day 182 and Day 385 which were normal, above normal, below the normal ranges or unknown.

Subjects were categorized according to their results at pre-vaccination (PRE), Day 42, Day 182 and Day 385 which were normal, above normal, below the normal ranges or unknown.

Subjects were categorized according to their results at pre-vaccination (PRE), Day 42, Day 182 and Day 385 which were normal, above normal, below the normal ranges or unknown.

Subjects were categorized according to their results at pre-vaccination (PRE), Day 42, Day 182 and Day 385 which were normal, above normal, below the normal ranges or unknown.

An unsolicited AE was defined as any AE (i.e. any 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) 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.

An unsolicited AE was defined as any AE (i.e. any 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) 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.

An unsolicited AE was defined as any AE (i.e. any 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) 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.

A SAE 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.

An unsolicited AE was defined as any AE (i.e. any 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) 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.

An unsolicited AE was defined as any AE (i.e. any 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) 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.

An unsolicited AE was defined as any AE (i.e. any 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) 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. As the study is still ongoing and data per age group are not available, results are presented for the groups pooled by vaccine/placebo administered. This outcome measure will be amended when data by age group become available.

A SAE 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.

For additional information about this study please refer to the GSK Clinical Study Register

For additional information about this study please refer to the GSK Clinical Study Register

For additional information about this study please refer to the GSK Clinical Study Register

For additional information about this study please refer to the GSK Clinical Study Register

For additional information about this study please refer to the GSK Clinical Study Register

Subjects aged at enrolment between 3 and 9 years, 9 years excluded, received 2 doses of Influenza A (H5N1) Virus monovalent vaccine (GSK1557484A vaccine or GSK Biologicals' monovalent A/Indonesia/5/2005 (H5N1) vaccine adjuvanted) at Days 0 and 21. Influenza A (H5N1) Virus monovalent vaccine was administered intramuscularly, Dose 1 in the deltoid region of the non-dominant arm (or left arm if dominance was not yet identified) and Dose 2 in the deltoid region of the dominant arm (or right arm).

Subjects aged at enrolment between 9 and 18 years, 18 years excluded, received 2 doses of Influenza A (H5N1) Virus monovalent vaccine (GSK1557484A vaccine or GSK Biologicals' monovalent A/Indonesia/5/2005 (H5N1) vaccine adjuvanted) at Days 0 and 21. Influenza A (H5N1) Virus monovalent vaccine was administered intramuscularly, Dose 1 in the deltoid region of the non-dominant arm (or left arm if dominance was not yet identified) and Dose 2 in the deltoid region of the dominant arm (or right arm).

Subjects aged at enrolment between 3 and 36 months, 36 months excluded, received 2 doses of saline placebo at Days 0 and 21. The saline placebo was administered intramuscularly. For children aged up to 12 months, 12 months excluded (<12 months), Dose 1 was administered in the left anterolateral thigh and Dose 2 in the right anterolateral thigh. For children older than (>=) 12 months, Dose 1 was administered in the deltoid region of the non-dominant arm (or left arm if dominance was not yet identified) and Dose 2 in the deltoid region of the dominant arm (or right arm).

Subjects aged at enrolment between 3 and 9 years, 9 years excluded, received 2 doses of saline placebo at Days 0 and 21. The saline placebo was administered intramuscularly, Dose 1 in the deltoid region of the non-dominant arm (or left arm if dominance was not yet identified) and Dose 2 in the deltoid region of the dominant arm (or right arm).

Subjects aged at enrolment between 9 and 18 years, 18 years excluded, received 2 doses of saline placebo at Days 0 and 21. The saline placebo was administered intramuscularly, Dose 1 in the deltoid region of the non-dominant arm (or left arm if dominance was not yet identified) and Dose 2 in the deltoid region of the dominant arm (or right arm).

Subjects in this group were those who were administered the saline placebo solution in the Blinded Phase of the study (either in the Placebo 6-<36M, Placebo 3-<9Y or Placebo 9-<18Y Group). These were subjects aged at enrolment between 6 months and 18 years, 18 years excluded, who had received 2 doses of saline placebo at Days 0 and 21 in the Blinded Phase of the study, as per described in the descriptions of the Placebo 6-<36M, Placebo 3-<9Y and Placebo 9-<18Y groups. After consenting to participating to the Unblinded Phase of the study, these subjects received in addition 2 doses of Influenza A (H5N1) Virus monovalent vaccine at Days 385 (Day U0) and Day 385 + 21 days (Day U21). Influenza A (H5N1) Virus monovalent vaccine was administered intramuscularly. Dose 1 was administered in the deltoid region of the non-dominant arm and Dose 2 in the deltoid region of the dominant arm.

Subjects aged at enrolment between 9 and 18 years, 18 years excluded, received 2 doses of Influenza A (H5N1) Virus monovalent vaccine (GSK1557484A vaccine or GSK Biologicals' monovalent A/Indonesia/5/2005 (H5N1) vaccine adjuvanted) at Days 0 and 21. Influenza A (H5N1) Virus monovalent vaccine was administered intramuscularly, Dose 1 in the deltoid region of the non-dominant arm (or left arm if dominance was not yet identified) and Dose 2 in the deltoid region of the dominant arm (or right arm).

Subjects aged at enrolment between 3 and 36 months, 36 months excluded, received 2 doses of saline placebo at Days 0 and 21. The saline placebo was administered intramuscularly. For children aged up to 12 months, 12 months excluded (< 12 months), Dose 1 was administered in the left anterolateral thigh and Dose 2 in the right anterolateral thigh. For children older than (>=) 12 months, Dose 1 was administered in the deltoid region of the non-dominant arm (or left arm if dominance was not yet identified) and Dose 2 in the deltoid region of the dominant arm (or right arm).

Subjects aged at enrolment between 3 and 9 years, 9 years excluded, received 2 doses of saline placebo at Days 0 and 21. The saline placebo was administered intramuscularly, Dose 1 in the deltoid region of the non-dominant arm (or left arm if dominance was not yet identified) and Dose 2 in the deltoid region of the dominant arm (or right arm).

Subjects aged at enrolment between 9 and 18 years, 18 years excluded, received 2 doses of saline placebo at Days 0 and 21. The saline placebo was administered intramuscularly, Dose 1 in the deltoid region of the non-dominant arm (or left arm if dominance was not yet identified) and Dose 2 in the deltoid region of the dominant arm (or right arm).

Subjects aged at enrolment between 9 and 18 years, 18 years excluded, received 2 doses of Influenza A (H5N1) Virus monovalent vaccine (GSK1557484A vaccine or GSK Biologicals' monovalent A/Indonesia/5/2005 (H5N1) vaccine adjuvanted) at Days 0 and 21. Influenza A (H5N1) Virus monovalent vaccine was administered intramuscularly, Dose 1 in the deltoid region of the non-dominant arm (or left arm if dominance was not yet identified) and Dose 2 in the deltoid region of the dominant arm (or right arm).

Subjects aged at enrolment between 3 and 36 months, 36 months excluded, received 2 doses of saline placebo at Days 0 and 21. The saline placebo was administered intramuscularly. For children aged up to 12 months, 12 months excluded (< 12 months), Dose 1 was administered in the left anterolateral thigh and Dose 2 in the right anterolateral thigh. For children older than (>=) 12 months, Dose 1 was administered in the deltoid region of the non-dominant arm (or left arm if dominance was not yet identified) and Dose 2 in the deltoid region of the dominant arm (or right arm).

Subjects aged at enrolment between 3 and 9 years, 9 years excluded, received 2 doses of saline placebo at Days 0 and 21. The saline placebo was administered intramuscularly, Dose 1 in the deltoid region of the non-dominant arm (or left arm if dominance was not yet identified) and Dose 2 in the deltoid region of the dominant arm (or right arm).

Subjects aged at enrolment between 9 and 18 years, 18 years excluded, received 2 doses of saline placebo at Days 0 and 21. The saline placebo was administered intramuscularly, Dose 1 in the deltoid region of the non-dominant arm (or left arm if dominance was not yet identified) and Dose 2 in the deltoid region of the dominant arm (or right arm).

Subjects aged at enrolment between 3 and 9 years, 9 years excluded, received 2 doses of Influenza A (H5N1) Virus monovalent vaccine (GSK1557484A vaccine or GSK Biologicals' monovalent A/Indonesia/5/2005 (H5N1) vaccine adjuvanted) at Days 0 and 21. Influenza A (H5N1) Virus monovalent vaccine was administered intramuscularly, Dose 1 in the deltoid region of the non-dominant arm (or left arm if dominance was not yet identified) and Dose 2 in the deltoid region of the dominant arm (or right arm).

Subjects aged at enrolment between 9 and 18 years, 18 years excluded, received 2 doses of Influenza A (H5N1) Virus monovalent vaccine (GSK1557484A vaccine or GSK Biologicals' monovalent A/Indonesia/5/2005 (H5N1) vaccine adjuvanted) at Days 0 and 21. Influenza A (H5N1) Virus monovalent vaccine was administered intramuscularly, Dose 1 in the deltoid region of the non-dominant arm (or left arm if dominance was not yet identified) and Dose 2 in the deltoid region of the dominant arm (or right arm).

Subjects aged at enrolment between 3 and 36 months, 36 months excluded, received 2 doses of saline placebo at Days 0 and 21. The saline placebo was administered intramuscularly. For children aged up to 12 months, 12 months excluded (< 12 months), Dose 1 was administered in the left anterolateral thigh and Dose 2 in the right anterolateral thigh. For children older than (>=) 12 months, Dose 1 was administered in the deltoid region of the non-dominant arm (or left arm if dominance was not yet identified) and Dose 2 in the deltoid region of the dominant arm (or right arm).

Subjects aged at enrolment between 3 and 9 years, 9 years excluded, received 2 doses of saline placebo at Days 0 and 21. The saline placebo was administered intramuscularly, Dose 1 in the deltoid region of the non-dominant arm (or left arm if dominance was not yet identified) and Dose 2 in the deltoid region of the dominant arm (or right arm).

Subjects aged at enrolment between 9 and 18 years, 18 years excluded, received 2 doses of saline placebo at Days 0 and 21. The saline placebo was administered intramuscularly, Dose 1 in the deltoid region of the non-dominant arm (or left arm if dominance was not yet identified) and Dose 2 in the deltoid region of the dominant arm (or right arm).

Subjects aged at enrolment between 9 and 18 years, 18 years excluded, received 2 doses of Influenza A (H5N1) Virus monovalent vaccine (GSK1557484A vaccine or GSK Biologicals' monovalent A/Indonesia/5/2005 (H5N1) vaccine adjuvanted) at Days 0 and 21. Influenza A (H5N1) Virus monovalent vaccine was administered intramuscularly, Dose 1 in the deltoid region of the non-dominant arm (or left arm if dominance was not yet identified) and Dose 2 in the deltoid region of the dominant arm (or right arm).

Subjects aged at enrolment between 3 and 36 months, 36 months excluded, received 2 doses of saline placebo at Days 0 and 21. The saline placebo was administered intramuscularly. For children aged up to 12 months, 12 months excluded (< 12 months), Dose 1 was administered in the left anterolateral thigh and Dose 2 in the right anterolateral thigh. For children older than (>=) 12 months, Dose 1 was administered in the deltoid region of the non-dominant arm (or left arm if dominance was not yet identified) and Dose 2 in the deltoid region of the dominant arm (or right arm).

Subjects aged at enrolment between 3 and 9 years, 9 years excluded, received 2 doses of saline placebo at Days 0 and 21. The saline placebo was administered intramuscularly, Dose 1 in the deltoid region of the non-dominant arm (or left arm if dominance was not yet identified) and Dose 2 in the deltoid region of the dominant arm (or right arm).

Subjects aged at enrolment between 9 and 18 years, 18 years excluded, received 2 doses of saline placebo at Days 0 and 21. The saline placebo was administered intramuscularly, Dose 1 in the deltoid region of the non-dominant arm (or left arm if dominance was not yet identified) and Dose 2 in the deltoid region of the dominant arm (or right arm).

Subjects aged at enrolment between 3 and 9 years, 9 years excluded, received 2 doses of Influenza A (H5N1) Virus monovalent vaccine (GSK1557484A vaccine or GSK Biologicals' monovalent A/Indonesia/5/2005 (H5N1) vaccine adjuvanted) at Days 0 and 21. Influenza A (H5N1) Virus monovalent vaccine was administered intramuscularly, Dose 1 in the deltoid region of the non-dominant arm (or left arm if dominance was not yet identified) and Dose 2 in the deltoid region of the dominant arm (or right arm).

Subjects aged at enrolment between 9 and 18 years, 18 years excluded, received 2 doses of Influenza A (H5N1) Virus monovalent vaccine (GSK1557484A vaccine or GSK Biologicals' monovalent A/Indonesia/5/2005 (H5N1) vaccine adjuvanted) at Days 0 and 21. Influenza A (H5N1) Virus monovalent vaccine was administered intramuscularly, Dose 1 in the deltoid region of the non-dominant arm (or left arm if dominance was not yet identified) and Dose 2 in the deltoid region of the dominant arm (or right arm).

Subjects aged at enrolment between 3 and 36 months, 36 months excluded, received 2 doses of saline placebo at Days 0 and 21. The saline placebo was administered intramuscularly. For children aged up to 12 months, 12 months excluded (< 12 months), Dose 1 was administered in the left anterolateral thigh and Dose 2 in the right anterolateral thigh. For children older than (>=) 12 months, Dose 1 was administered in the deltoid region of the non-dominant arm (or left arm if dominance was not yet identified) and Dose 2 in the deltoid region of the dominant arm (or right arm).

Subjects aged at enrolment between 3 and 9 years, 9 years excluded, received 2 doses of saline placebo at Days 0 and 21. The saline placebo was administered intramuscularly, Dose 1 in the deltoid region of the non-dominant arm (or left arm if dominance was not yet identified) and Dose 2 in the deltoid region of the dominant arm (or right arm).

Subjects aged at enrolment between 9 and 18 years, 18 years excluded, received 2 doses of saline placebo at Days 0 and 21. The saline placebo was administered intramuscularly, Dose 1 in the deltoid region of the non-dominant arm (or left arm if dominance was not yet identified) and Dose 2 in the deltoid region of the dominant arm (or right arm).

Subjects aged at enrolment between 3 and 9 years, 9 years excluded, received 2 doses of Influenza A (H5N1) Virus monovalent vaccine (GSK1557484A vaccine or GSK Biologicals' monovalent A/Indonesia/5/2005 (H5N1) vaccine adjuvanted) at Days 0 and 21. Influenza A (H5N1) Virus monovalent vaccine was administered intramuscularly, Dose 1 in the deltoid region of the non-dominant arm (or left arm if dominance was not yet identified) and Dose 2 in the deltoid region of the dominant arm (or right arm).

Subjects aged at enrolment between 9 and 18 years, 18 years excluded, received 2 doses of Influenza A (H5N1) Virus monovalent vaccine (GSK1557484A vaccine or GSK Biologicals' monovalent A/Indonesia/5/2005 (H5N1) vaccine adjuvanted) at Days 0 and 21. Influenza A (H5N1) Virus monovalent vaccine was administered intramuscularly, Dose 1 in the deltoid region of the non-dominant arm (or left arm if dominance was not yet identified) and Dose 2 in the deltoid region of the dominant arm (or right arm).

Subjects aged at enrolment between 3 and 36 months, 36 months excluded, received 2 doses of saline placebo at Days 0 and 21. The saline placebo was administered intramuscularly. For children aged up to 12 months, 12 months excluded (< 12 months), Dose 1 was administered in the left anterolateral thigh and Dose 2 in the right anterolateral thigh. For children older than (>=) 12 months, Dose 1 was administered in the deltoid region of the non-dominant arm (or left arm if dominance was not yet identified) and Dose 2 in the deltoid region of the dominant arm (or right arm).

Subjects aged at enrolment between 3 and 9 years, 9 years excluded, received 2 doses of saline placebo at Days 0 and 21. The saline placebo was administered intramuscularly, Dose 1 in the deltoid region of the non-dominant arm (or left arm if dominance was not yet identified) and Dose 2 in the deltoid region of the dominant arm (or right arm).

Subjects aged at enrolment between 9 and 18 years, 18 years excluded, received 2 doses of saline placebo at Days 0 and 21. The saline placebo was administered intramuscularly, Dose 1 in the deltoid region of the non-dominant arm (or left arm if dominance was not yet identified) and Dose 2 in the deltoid region of the dominant arm (or right arm).

Subjects aged at enrolment between 3 and 9 years, 9 years excluded, received 2 doses of Influenza A (H5N1) Virus monovalent vaccine (GSK1557484A vaccine or GSK Biologicals' monovalent A/Indonesia/5/2005 (H5N1) vaccine adjuvanted) at Days 0 and 21. Influenza A (H5N1) Virus monovalent vaccine was administered intramuscularly, Dose 1 in the deltoid region of the non-dominant arm (or left arm if dominance was not yet identified) and Dose 2 in the deltoid region of the dominant arm (or right arm).

Subjects aged at enrolment between 9 and 18 years, 18 years excluded, received 2 doses of Influenza A (H5N1) Virus monovalent vaccine (GSK1557484A vaccine or GSK Biologicals' monovalent A/Indonesia/5/2005 (H5N1) vaccine adjuvanted) at Days 0 and 21. Influenza A (H5N1) Virus monovalent vaccine was administered intramuscularly, Dose 1 in the deltoid region of the non-dominant arm (or left arm if dominance was not yet identified) and Dose 2 in the deltoid region of the dominant arm (or right arm).

Subjects aged at enrolment between 3 and 36 months, 36 months excluded, received 2 doses of saline placebo at Days 0 and 21. The saline placebo was administered intramuscularly. For children aged up to 12 months, 12 months excluded (< 12 months), Dose 1 was administered in the left anterolateral thigh and Dose 2 in the right anterolateral thigh. For children older than (>=) 12 months, Dose 1 was administered in the deltoid region of the non-dominant arm (or left arm if dominance was not yet identified) and Dose 2 in the deltoid region of the dominant arm (or right arm).

Subjects aged at enrolment between 3 and 9 years, 9 years excluded, received 2 doses of saline placebo at Days 0 and 21. The saline placebo was administered intramuscularly, Dose 1 in the deltoid region of the non-dominant arm (or left arm if dominance was not yet identified) and Dose 2 in the deltoid region of the dominant arm (or right arm).

Subjects aged at enrolment between 9 and 18 years, 18 years excluded, received 2 doses of saline placebo at Days 0 and 21. The saline placebo was administered intramuscularly, Dose 1 in the deltoid region of the non-dominant arm (or left arm if dominance was not yet identified) and Dose 2 in the deltoid region of the dominant arm (or right arm).

SSubjects aged at enrolment between 3 and 9 years, 9 years excluded, received 2 doses of Influenza A (H5N1) Virus monovalent vaccine (GSK1557484A vaccine or GSK Biologicals' monovalent A/Indonesia/5/2005 (H5N1) vaccine adjuvanted) at Days 0 and 21. Influenza A (H5N1) Virus monovalent vaccine was administered intramuscularly, Dose 1 in the deltoid region of the non-dominant arm (or left arm if dominance was not yet identified) and Dose 2 in the deltoid region of the dominant arm (or right arm).

Subjects aged at enrolment between 9 and 18 years, 18 years excluded, received 2 doses of Influenza A (H5N1) Virus monovalent vaccine (GSK1557484A vaccine or GSK Biologicals' monovalent A/Indonesia/5/2005 (H5N1) vaccine adjuvanted) at Days 0 and 21. Influenza A (H5N1) Virus monovalent vaccine was administered intramuscularly, Dose 1 in the deltoid region of the non-dominant arm (or left arm if dominance was not yet identified) and Dose 2 in the deltoid region of the dominant arm (or right arm).

Subjects aged at enrolment between 3 and 36 months, 36 months excluded, received 2 doses of saline placebo at Days 0 and 21. The saline placebo was administered intramuscularly. For children aged up to 12 months, 12 months excluded (< 12 months), Dose 1 was administered in the left anterolateral thigh and Dose 2 in the right anterolateral thigh. For children older than (>=) 12 months, Dose 1 was administered in the deltoid region of the non-dominant arm (or left arm if dominance was not yet identified) and Dose 2 in the deltoid region of the dominant arm (or right arm).

Subjects aged at enrolment between 3 and 9 years, 9 years excluded, received 2 doses of saline placebo at Days 0 and 21. The saline placebo was administered intramuscularly, Dose 1 in the deltoid region of the non-dominant arm (or left arm if dominance was not yet identified) and Dose 2 in the deltoid region of the dominant arm (or right arm).

Subjects aged at enrolment between 9 and 18 years, 18 years excluded, received 2 doses of saline placebo at Days 0 and 21. The saline placebo was administered intramuscularly, Dose 1 in the deltoid region of the non-dominant arm (or left arm if dominance was not yet identified) and Dose 2 in the deltoid region of the dominant arm (or right arm).

Subjects aged at enrolment between 9 and 18 years, 18 years excluded, received 2 doses of Influenza A (H5N1) Virus monovalent vaccine (GSK1557484A vaccine or GSK Biologicals' monovalent A/Indonesia/5/2005 (H5N1) vaccine adjuvanted) at Days 0 and 21. Influenza A (H5N1) Virus monovalent vaccine was administered intramuscularly, Dose 1 in the deltoid region of the non-dominant arm (or left arm if dominance was not yet identified) and Dose 2 in the deltoid region of the dominant arm (or right arm).

Subjects aged at enrolment between 3 and 36 months, 36 months excluded, received 2 doses of saline placebo at Days 0 and 21. The saline placebo was administered intramuscularly. For children aged up to 12 months, 12 months excluded (< 12 months), Dose 1 was administered in the left anterolateral thigh and Dose 2 in the right anterolateral thigh. For children older than (>=) 12 months, Dose 1 was administered in the deltoid region of the non-dominant arm (or left arm if dominance was not yet identified) and Dose 2 in the deltoid region of the dominant arm (or right arm).

Subjects aged at enrolment between 3 and 9 years, 9 years excluded, received 2 doses of saline placebo at Days 0 and 21. The saline placebo was administered intramuscularly, Dose 1 in the deltoid region of the non-dominant arm (or left arm if dominance was not yet identified) and Dose 2 in the deltoid region of the dominant arm (or right arm).

Subjects aged at enrolment between 9 and 18 years, 18 years excluded, received 2 doses of saline placebo at Days 0 and 21. The saline placebo was administered intramuscularly, Dose 1 in the deltoid region of the non-dominant arm (or left arm if dominance was not yet identified) and Dose 2 in the deltoid region of the dominant arm (or right arm).

Subjects aged at enrolment between 3 and 9 years, 9 years excluded, received 2 doses of Influenza A (H5N1) Virus monovalent vaccine (GSK1557484A vaccine or GSK Biologicals' monovalent A/Indonesia/5/2005 (H5N1) vaccine adjuvanted) at Days 0 and 21. Influenza A (H5N1) Virus monovalent vaccine was administered intramuscularly, Dose 1 in the deltoid region of the non-dominant arm (or left arm if dominance was not yet identified) and Dose 2 in the deltoid region of the dominant arm (or right arm).

Subjects aged at enrolment between 9 and 18 years, 18 years excluded, received 2 doses of Influenza A (H5N1) Virus monovalent vaccine (GSK1557484A vaccine or GSK Biologicals' monovalent A/Indonesia/5/2005 (H5N1) vaccine adjuvanted) at Days 0 and 21. Influenza A (H5N1) Virus monovalent vaccine was administered intramuscularly, Dose 1 in the deltoid region of the non-dominant arm (or left arm if dominance was not yet identified) and Dose 2 in the deltoid region of the dominant arm (or right arm).

Subjects aged at enrolment between 3 and 36 months, 36 months excluded, received 2 doses of saline placebo at Days 0 and 21. The saline placebo was administered intramuscularly. For children aged up to 12 months, 12 months excluded (&lt; 12 months), Dose 1 was administered in the left anterolateral thigh and Dose 2 in the right anterolateral thigh. For children older than (&gt;=) 12 months, Dose 1 was administered in the deltoid region of the non-dominant arm (or left arm if dominance was not yet identified) and Dose 2 in the deltoid region of the dominant arm (or right arm).

Subjects aged at enrolment between 3 and 9 years, 9 years excluded, received 2 doses of saline placebo at Days 0 and 21. The saline placebo was administered intramuscularly, Dose 1 in the deltoid region of the non-dominant arm (or left arm if dominance was not yet identified) and Dose 2 in the deltoid region of the dominant arm (or right arm).

Subjects aged at enrolment between 9 and 18 years, 18 years excluded, received 2 doses of saline placebo at Days 0 and 21. The saline placebo was administered intramuscularly, Dose 1 in the deltoid region of the non-dominant arm (or left arm if dominance was not yet identified) and Dose 2 in the deltoid region of the dominant arm (or right arm).