High-Dose Quadrivalent Influenza Vaccine 30 μg

An unsolicited AE was an observed AE that did not fulfill the conditions prelisted in the case report book (CRB) in terms of diagnosis and/or onset window post-vaccination. Unsolicited AEs includes both serious (SAEs) and non-serious unsolicited AEs. An SAE was any untoward medical occurrence that at any dose resulted in death, was life-threatening, required inpatient hospitalization or prolongation of existing hospitalization, resulted in persistent or significant disability/incapacity, was a congenital anomaly/birth defect, or was an important medical event. All participants were observed for 30 minutes after vaccination, and any unsolicited systemic AEs occurred during that time were recorded as immediate unsolicited AEs in the CRB.

An unsolicited AE was an observed AE that does not fulfill the conditions prelisted in the CRB in terms of diagnosis and/or onset window post-vaccination. Unsolicited AEs included both serious and non-serious unsolicited AEs. An SAE was any untoward medical occurrence that at any dose resulted in death, was life-threatening, required inpatient hospitalization or prolongation of existing hospitalization, resulted in persistent or significant disability/incapacity, was a congenital anomaly/birth defect, or was an important medical event. Adverse reactions (ARs) were AEs related to vaccination. An injection site reaction was an AR at and around the injection site. Systemic AEs were all AEs that were not injection or administration site reactions.

An SAE was any untoward medical occurrence that at any dose resulted in death, was life-threatening, required inpatient hospitalization or prolongation of existing hospitalization, resulted in persistent or significant disability/incapacity, was a congenital anomaly/birth defect, or was an important medical event. An SAE which caused death of the participant was considered as fatal SAE. Adverse events of special interest (AESIs) were defined as SAEs which included new onset of Guillain-Barré syndrome, encephalitis/myelitis (including transverse myelitis), Bell's palsy, convulsions, optic neuritis, and brachial neuritis.

Anti-influenza antibodies were measured by hemagglutination inhibition (HAI) assay for strains A/H1N1, A/H3N2, B/Victoria and B/Yamagata lineage. Seroconversion: defined as either HAI titer \<10(1/dilution) at Day 0 and post-vaccination titer greater than or equal to (\>=)40(1/dilution) at Day 28, or HAI titer \>=10(1/dilution) at Day 0 and \>=4-fold increase in HAI titer (1/dilution) at Day 28. Data for this Outcome Measure (OM) was planned to be collected and reported for dose level (QIV-HD 30μg and 45μg) matched separate groups for QIV-SD (Groups 4a, 4b and 4c), instead of pooled QIV-SD arm. Due to complex study design and analysis of doses and age groups, QIV-SD group participants, who matched to participants in QIV-HD 30μg and 45μg dose formulations groups (who were 9 through 17 years old and shared matching age group with QIV-SD control group), included in Groups 4a, 4b and 4c in this OM might be counted in more than once in QIV-SD arms for different dose levels, as applicable.

GMTs of anti-influenza antibodies were measured using an HAI assay for 4 strains: A/H1N1, A/H3N2, B Victoria lineage, and B Yamagata lineage. Data for this OM was planned to be collected and reported for dose level (QIV-HD 30 μg and QIV-HD 45 μg) matched separate groups for QIV-SD (Groups 4a, 4b and 4c), instead of pooled QIV-SD arm. Due to the complex study design and analysis of the dose formulation and age groups in the study, QIV-SD group participants, who matched to participants in the QIV-HD 30 μg and QIV-HD 45 μg dose formulations groups (who were 9 through 17 years old and shared a matching age group with QIV-SD control group), included in Groups 4a, 4b and 4c in this OM might be counted in more than once in QIV-SD arms for different dose levels, as applicable.

GMTs of anti-influenza antibodies were measured using an HAI assay for 4 strains: A/H1N1, A/H3N2, B Victoria lineage, and B Yamagata lineage. GMTRs were calculated as the ratio of GMTs post-vaccination and pre-vaccination.

GMT was measured for each influenza strain using HAI assay method for 4 strains: A/H1N1, A/H3N2, B/Victoria lineage, and B/Yamagata lineage.

GMT was measured for each influenza strain using SN assay method for 4 strains: A/H1N1, A/H3N2, B/Victoria lineage, and B/Yamagata lineage.

GMTRs of anti-influenza antibodies were measured using SN assay method for 4 strains: A/H1N1, A/H3N2, B/Victoria lineage and B/Yamagata lineage. GMTRs were calculated as the ratio of GMTs post vaccination and pre-vaccination.

Neutralizing Antibody titer was measured for each influenza strain with SN assay method for 4 strains: A/H1N1, A/H3N2, B/Victoria lineage, and B/Yamagata lineage at pre-defined thresholds of \>=20, \>=40 and \>=80 (1/dilution).

Neutralizing Antibody titer was measured for each influenza strain with SN method for 4 strains: A/H1N1, A/H3N2, B/Victoria lineage, and B/Yamagata lineage. 2-fold and 4-fold rise was defined as the computed value = post-vaccination computed value / pre-vaccination computed value.

A solicited reaction was an expected adverse reaction (sign or symptom) observed and reported under the conditions (nature and onset) prelisted (i.e., solicited) in the CRB and considered as related to the administered vaccination. Solicited injection site reactions included tenderness/pain, erythema, swelling, induration and bruising.

A solicited reaction was an expected adverse reaction (sign or symptom) observed and reported under the conditions (nature and onset) prelisted (i.e., solicited) in the CRB and considered as related to the administered vaccination. Solicited systemic reactions included fever, vomiting, crying abnormal, drowsiness, appetite loss and irritability. Fever was planned to be evaluated for the whole population where as, the other events (vomiting, crying abnormal, drowsiness, appetite lost, and irritability) were planned to be evaluated only in the participants aged 6 months to \<36 months.

A solicited reaction was an expected adverse reaction (sign or symptom) observed and reported under the conditions (nature and onset) prelisted (i.e., solicited) in the CRB and considered as related to the administered vaccination. Solicited systemic reactions included: headache, malaise, myalgia and shivering.