Influenza, Human
Conditions
Keywords
Influenza vaccine
Brief summary
This Phase 3/4, randomized, observer-blind, multi-center study, stratified study evaluated the immune (antibody) response, efficacy and safety of a cell-derived quadrivalent subunit influenza virus vaccine (Seqirus QIVc) in comparison with a non-influenza comparator, meningococcal serogroup A, C, W-135, and Y (Menveo®, GlaxoSmithKline Biologicals, S.A.) in healthy pediatric subjects ≥2 Years to \<18 Years of Age
Detailed description
This Phase 3/4, randomized, observer-blind, multi-center, stratified study evaluated the efficacy, safety, and immunogenicity of a cell-derived quadrivalent subunit influenza virus vaccine (Seqirus QIVc) compared to a non-influenza comparator vaccine in healthy male and female participants between 2 to \<18 years of age. A total of 4514 children/teens were randomized, receiving either QIVc or the non-influenza comparator vaccine. The comparator was (meningococcal \[Groups A, C, W-135, and Y\] oligosaccharide diphtheria CRM197 conjugate vaccine \[Men ACWY\]). Randomized enrollment was stratified in a 1:1 ratio via an Interactive Response Technology (IRT) system which assigned the participants into two age cohorts: 2 to \<9 years of age and 9 to \<18 years of age. Subjects between 2 to \<9 years of age were further stratified by previous influenza vaccine status (previously vaccinated or not previously vaccinated).
Interventions
BIOLOGICALQIVc
Cell-derived Quadrivalent Influenza Vaccine for intramuscular use containing each of the 2 influenza type A strains and each of the 2 influenza type B strains
BIOLOGICALNon-influenza Comparator Vaccine
Non-influenza comparator vaccine for intramuscular use
Sponsors
Seqirus
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
QUADRUPLE (Subject, Caregiver, Investigator, Outcomes Assessor)
Intervention model description
Phase 3/4
Eligibility
Sex/Gender
ALL
Age
2 Years to 17 Years
Healthy volunteers
Yes
Inclusion criteria
* Male or female ≥2 to \<18 years of age on the day of the first study vaccination * Subject's parent(s) or legal guardian(s) who was/were able to give informed consent/dissent after the nature of the study had been explained in accordance with the practices described in the study and according to local regulatory requirements * If the subject was of an age where, according to local regulations, informed assent was required, he/she must have provided assent to participate in the study * Subject/subject's parent(s) or legal guardian(s) was/were able to comply with study procedures and was/were available for follow-up; and * Subject was in generally good health as per the investigator's medical judgment
Exclusion criteria
* Clinical signs of fever and/or an oral temperature of ≥100.4°F (38.0°C) within 3 days prior to vaccination; * A known history of any anaphylaxis, serious vaccine reactions or hypersensitivity to any of the vaccine components described in the Investigator's Brochure, or had any of the contraindications listed in the package insert of the comparator vaccine; * A history of Guillain-Barré syndrome or other de-myelinating diseases such as encephalomyelitis and transverse myelitis; * Female subject of childbearing potential (ie, post onset of menarche and before natural or induced menopause), sexually active, and who did not use any acceptable contraceptive methods for at least 2 months prior to study entry and who did not intend to use any acceptable contraceptive methods throughout subject participation (acceptable contraceptive methods included: abstinence; hormonal contraceptive \[such as oral, injection, transdermal patch, implant\]; diaphragm with spermicide; tubal occlusion device; intrauterine device \[IUD\]; tubal ligation; male partner using condom; or male partner having been vasectomized); * Pregnant or breast feeding female; * Subject and/or subject's parent/guardians who were not able to comprehend or follow all required study procedures for the entire period of the study; * Received prior Meningococcal ACWY vaccination that conflicted with national recommendations or local practices for the timing of the primary or the booster vaccination; * Received influenza vaccination or had documented influenza disease in the last 6 months; * Known or suspected congenital or acquired immunodeficiency; or received immunosuppressive therapy, such as anti-cancer chemotherapy or radiation therapy, within the preceding 6 months; or systemic corticosteroid therapy (prednisone or equivalent) at any dose for more than 2 consecutive weeks (14 days) within the past 3 months. Topical, inhaled and intra-nasal corticosteroids were permitted. Intermittent use (1 dose in 30 days) of intra-articular corticosteroids was also permitted; * Administration of immunoglobulin and/or any blood products within the 3 months preceding vaccination, or administration was planned during the study; * Participated in any clinical study with another investigational product within 30 days prior to first study visit or intended to participate in another clinical study at any time during the conduct of this study. Concomitant participation in an observational study (not involving drugs, vaccines, or medical devices) was acceptable; * Medical conditions or treatments contraindicating IM vaccination due to increased risk of bleeding. These included known bleeding disorders (such as thrombocytopenia), or treatment with anticoagulants (such as warfarin) in the 3 weeks preceding vaccination. Antiplatelet agents such as low-dose aspirin, ticlopidine (Ticlid) and clopidogrel (Plavix) were permitted; * Evidence or history (within the previous 12 months) of drug or alcohol abuse; * Study personnel or immediate family members (brother, sister, child, parent), the spouse of study personnel or individuals who were financially or emotionally dependent on study staff; * Participated in this study in a prior season, if applicable; or * Any clinical condition that, in the opinion of the investigator, may have interfered with the results of the study or pose additional risk to the subject due to participation in the study.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Primary Efficacy: First Occurrence of Either RT-PCR- or Culture-confirmed Influenza (Time-to-event Analyses) Due to Any Influenza Type A or B Strain Regardless of Antigenic Match to the Strains Selected for the Seasonal Vaccine in Subjects ≥2 to <18 Years | Day 14 to Day 180 or until the end of the influenza season, whichever is longer | The primary efficacy endpoint was defined as the time from the last study vaccination to the onset of the first occurrence of either RT-PCR- or culture-confirmed influenza (time-to-event analyses) due to any influenza Type A or B strain regardless of antigenic match to the strains selected for the seasonal vaccine, that occurred more than 14 days after the last vaccination until the end of the influenza season. Dataset Used: FAS-Efficacy = All subjects in the All Enrolled Set who received at least one dose of study vaccine and were evaluated for efficacy from 14 days after the last vaccination. The success criterion used for this primary objective was as follows: The efficacy of the QIVc was demonstrated if the lower limit (LL) of the 2-sided 95% confidence interval (CI) for VE was above 20%. |
| Co-Primary: First Occurrence of Either RT-PCR- or Culture-confirmed Influenza (Time-to-event Analyses) Due to Any Influenza Type A or B Strain Regardless of Antigenic Match to the Strains Selected for the Seasonal Vaccine in Subjects ≥3 to <18 Years | Day 14 to Day 180 or until the end of the influenza season, whichever is longer | The co-primary efficacy endpoint: was defined as the time from the last study vaccination to the onset of the first occurrence of either RT-PCR- or culture-confirmed influenza (time-to-event analyses) due to any influenza Type A or B strain regardless of antigenic match to the strains selected for the seasonal vaccine, that occurred more than 14 days after the last vaccination until the end of the influenza season.Absolute vaccine efficacy of QIVc by first occurrence RT-PCR or culture confirmed influenza, due to any influenza Type A and B strain in subjects ≥3 years to \<18 years of age |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Secondary Efficacy #3: First Occurrence of Culture-confirmed Influenza Due to Any Influenza Type A or B Strain Regardless of Antigenic Match to the Strains Selected for the Seasonal Vaccine | Day 14 to Day 180 or until the end of the influenza season, whichever is longer. | The secondary endpoint was defined as the time from the last study vaccination to the onset of the first occurrence of culture-confirmed influenza due to any influenza Type A or B strain regardless of antigenic match to the strains selected for the seasonal vaccine, that occurred more than 14 days after the last vaccination until the end of the influenza season in subjects 2 to \<18 years, 2 to \<9 years, 4 to \<18 years, and 9 to \<18 years. Dataset used: FAS Efficacy |
| Secondary Efficacy #4: First Occurrence of Culture-confirmed Influenza Due to Influenza Type A or B Strain Antigenically Matched to the Strains Selected for the Seasonal Vaccine | Day 14 to Day 180 or until the end of the influenza season, whichever is longer. | The endpoint was defined as the time from the last study vaccination to the onset of the first occurrence of culture-confirmed influenza due to influenza Type A or B strain antigenically matched to the strains selected for the seasonal vaccine, that occurred more than 14 days after the last vaccination until the end of the influenza season in subjects 2 to \<18 years, 2 to \<9 years, 4 to \<18 years, and 9 to \<18 years. |
| Secondary Immunogenicity: Geometric Mean Titers for 4 Influenza Strains (HI Assay) | Day 1 (all subjects), Day 22 (all previously vaccinated subjects) or Day 29 and Day 50 (all not previously vaccinated subjects receiving 2 doses) | Immunogenicity was characterized by HI assay 3 weeks after the last vaccination in a subset of subjects 2 to \<9 years of age enrolled in Season 2 (n=432) and Season 3 (n=319) who were immunized and had immunogenicity data at the assessed timepoints (FAS Immunogenicity). Immunogenicity was assessed at baseline (Day 1; all subjects in immunogenicity subset), at Day 22 (all previously vaccinated subjects receiving a single dose of the study vaccine), and at Days 29 and 50 (all not previously vaccinated subjects receiving 2 doses) for all 4 influenza strains using the HI assay. |
| ISecondary Immunogenicity: Percentage of Subjects Achieving Seroconversion for 4 Influenza Strains (HI Assay) | Day 22 (all previously vaccinated subjects) or Day 29 and Day 50 (all not previously vaccinated subjects) | Immunogenicity was characterized by HI assay 3 weeks after the last vaccination in a subset of subjects 2 to \<9 years of age enrolled in Season 2 (n=432) and Season 3 (n=319) who were immunized and had immunogenicity data at the assessed timepoints (FAS Immunogenicity). Immunogenicity was assessed at baseline (Day 1; all subjects in immunogenicity subset), at Day 22 (all previously vaccinated subjects receiving a single dose of the study vaccine), and at Days 29 and 50 (all not previously vaccinated subjects receiving 2 doses) for all 4 influenza strains using the HI assay. Seroconversion was defined as: either a prevaccination HI titer \<1:10 and a postvaccination HI titer ≥1:40 or a prevaccination HI titer ≥1:10 and a ≥4 fold increase in postvaccination HI titer) Dataset used: FAS Immunogenicity = All subjects in the All Enrolled Set who received at least one dose of study vaccine and provided evaluable serum samples at both baseline and after the last vaccination. |
| Secondary Efficacy #1: First Occurrence of Either RT-PCR- or Culture-confirmed Influenza Due to Any Influenza Type A or B Strain Regardless of Antigenic Match to the Strains Selected for the Seasonal Vaccine | Day 14 to Day 180 or until the end of the influenza season, whichever is longer. | The endpoint was defined as the time from the last study vaccination to the onset of the first occurrence of either RT-PCR- or culture-confirmed influenza due to any influenza Type A or B strain regardless of antigenic match to the strains selected for the seasonal vaccine, that occurred more than 14 days after the last vaccination until the end of the influenza season in subjects 2 to \<18 years, 2 to \<9 years, 4 to \<18 years, and 9 to \<18 years. Dataset used: FAS Efficacy = All subjects in the All Enrolled Set who received at least one dose of study vaccine and were evaluated for efficacy from 14 days after the last vaccination. |
| Secondary Immunogenicity: Percentage of Subjects With HI Titer ≥1:40 for All 4 Influenza Strains (HI Assay) | Day 1 (all subjects), Day 22 (all previously vaccinated subjects receiving a single vaccine dose) or Days 29 and 50 (all not previously vaccinatedsubjects receiving 2 doses) | Immunogenicity was characterized by HI assay 3 weeks after the last vaccination in a subset of subjects 2 to \<9 years of age enrolled in Season 2 (n=432) and Season 3 (n=319) who were immunized and had immunogenicity data at the assessed timepoints (FAS Immunogenicity). Immunogenicity was assessed at baseline (Day 1; all subjects in immunogenicity subset), at Day 22 (all previously vaccinated subjects receiving a single dose of the study vaccine), and at Days 29 and 50 (all not previously vaccinated subjects receiving 2 doses) for all 4 influenza strains using the HI assay. The measures for assessing immunogenicity as determined by HI were as follows: Percentage of subjects with an HI titer ≥1:40 on Day 22 (all previously vaccinated subjects receiving a single vaccine dose) or Days 29 and 50 (all not previously vaccinated subjects receiving 2 doses) for all 4 influenza strains |
| Safety: Percentage of Subjects With Solicited Local and Systemic Adverse Events for 7 Days After Vaccination | days after vaccination on Day 1 (for previously vaccinated subjects) or for 7 days after vaccination on Day 1 and Day 29 (for not previously vaccinated subjects) | The measures for assessing safety and tolerability were as follows: Percentage of subjects with solicited local and systemic adverse events (AEs) for 7 days after vaccination on Day 1 (for previously vaccinated subjects) or for 7 days after vaccination on Day 1 and Day 29 (for not previously vaccinated subjects) in the QIVc group and the non-influenza comparator vaccine group. Dataset used: Solicited Safety Set |
| Safety: Percentage of Subjects With Unsolicited AEs for 21 Days After Vaccination | Day 1 to Day 22 (for previously vaccinated subjects) or Day 1 to Day 50 (for not previously vaccinated subjects) | The measures for assessing safety and tolerability were as follows: Percentage of subjects with unsolicited AEs assessed from Day 1 to Day 22 (for previously vaccinated subjects) or from Day 1 to Day 50 (for not previously vaccinated subjects) in the QIVc group and the non-influenza comparator vaccine group. Dataset used: Unsolicited Safety Set (Unsolicited Adverse Events) |
| Safety: Subjects With SAEs, AEs Leading to Withdrawal From Vaccination and/or the Study,(MAAEs) Within 30 Days of a 1st Occurrence, Post-ILI, and NOCDs Reported During Entire Study Participation or End of Flue Season, Whichever Was Longer | Day 1 to Day 181 (for previously vaccinated subjects) or to Day 209 (for not previously vaccinated subjects) | The measures for assessing safety and tolerability were as follows: Percentage of subjects with SAEs, AEs leading to withdrawal from vaccination and/or the study, Medically-Attended AEs (MAAEs) within 30 days after the first occurrence of an ILI, and New Onset of Chronic Diseases (NOCDs) reported during the subject's entire participation in the study (ie, from Day 1 to Day 181 \[for previously vaccinated subjects\] or from Day 1 to Day 209 \[for not previously vaccinated subjects\]), or until the end of influenza season, whichever was longer, and all medications associated with these events. Dataset used: Overall Safety Set |
| Secondary Immunogenicity: Geometric Mean Ratio for 4 Influenza Strains (HI Assay) | Day 22/Day 1 (all previously vaccinated subjects) or Day 29/Day 1 and Day 50/Day 1 (all not previously vaccinated subjects receiving 2 doses) | Immunogenicity was characterized by HI assay 3 weeks after the last vaccination in a subset of subjects 2 to \<9 years of age enrolled in Season 2 (n=432) and Season 3 (n=319) who were immunized and had immunogenicity data at the assessed timepoints (FAS Immunogenicity). Immunogenicity was assessed at baseline (Day 1; all subjects in immunogenicity subset), at Day 22 (all previously vaccinated subjects receiving a single dose of the study vaccine), and at Days 29 and 50 (all not previously vaccinated subjects receiving 2 doses) for all 4 influenza strains using the HI assay. Geometric mean ratios (GMRs) measure the ratio in immunogenicity titers within subject\\ Dataset used: FAS Immunogenicity = All subjects in the All Enrolled Set who received at least one dose of study vaccine and provided evaluable serum samples at both baseline and after the last vaccination. |
| Secondary Efficacy #2: First Occurrence of RT-PCR-confirmed Influenza Due to Any Influenza Type A or B Strain Regardless of Antigenic Match to the Strains Selected for the Seasonal Vaccine | Day 14 to Day 180 or until the end of the influenza season, whichever is longer. | The endpoint was defined as the time from the last study vaccination to the onset of the first occurrence of RT-PCR-confirmed influenza due to any influenza Type A or B strain regardless of antigenic match to the strains selected for the seasonal vaccine, that occurred more than 14 days after the last vaccination until the end of the influenza season in subjects 2 to \<18 years, 2 to \<9 years, 4 to \<18 years, and 9 to \<18 years Dataset used: FAS Efficacy - All subjects in the All Enrolled Set who received at least one dose of study vaccine and were evaluated for efficacy from 14 days after the last vaccination. |
Countries
Australia, Estonia, Finland, Lithuania, Philippines, Poland, Spain, Thailand
Participant flow
Recruitment details
Subjects were enrolled over 3 seasons, starting in SH 2017, followed by NH 2017-2018 and NH 2018-2019. Recruitment was conducted in 8 countries over these 3 seasons: Australia, Philippines and Thailand (Season 1); Estonia and Finland i(Season 2); and Estonia, Finland, Lithuania, Poland and Spain (Season 3)
Participants by arm
| Arm | Count |
|---|---|
| QIVc (≥2 Years to <18 Years of Age) Cell-derived Seasonal Quadrivalent Influenza Vaccine
QIVc: Cell-derived Quadrivalent Influenza Vaccine for intramuscular use containing each of the 2 influenza type A strains and each of the 2 influenza type B strains | 2,258 |
| Non-Influenza Comparator Vaccine Non-Influenza Comparator Vaccine
Non-influenza Comparator Vaccine: Non-influenza comparator vaccine for intramuscular use | 2,256 |
| Total | 4,514 |
Baseline characteristics
| Characteristic | QIVc (≥2 Years to <18 Years of Age) | Total | Non-Influenza Comparator Vaccine |
|---|---|---|---|
| Age, Continuous | 8.7 years STANDARD_DEVIATION 4 | 8.8 years STANDARD_DEVIATION 4.06 | 8.9 years STANDARD_DEVIATION 4.11 |
| Ethnicity (NIH/OMB) Hispanic or Latino | 11 Participants | 22 Participants | 11 Participants |
| Ethnicity (NIH/OMB) Not Hispanic or Latino | 2245 Participants | 4490 Participants | 2245 Participants |
| Ethnicity (NIH/OMB) Unknown or Not Reported | 2 Participants | 2 Participants | 0 Participants |
| Race (NIH/OMB) American Indian or Alaska Native | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Asian | 1106 Participants | 2206 Participants | 1100 Participants |
| Race (NIH/OMB) Black or African American | 1 Participants | 1 Participants | 0 Participants |
| Race (NIH/OMB) More than one race | NA Participants | NA Participants | NA Participants |
| Race (NIH/OMB) Native Hawaiian or Other Pacific Islander | 0 Participants | 2 Participants | 2 Participants |
| Race (NIH/OMB) Unknown or Not Reported | 11 Participants | 26 Participants | 15 Participants |
| Race (NIH/OMB) White | 1140 Participants | 2279 Participants | 1139 Participants |
| Region of Enrollment Australia | 96 Participants | 195 Participants | 99 Participants |
| Region of Enrollment Estonia | 599 Participants | 1198 Participants | 599 Participants |
| Region of Enrollment Finland | 168 Participants | 326 Participants | 158 Participants |
| Region of Enrollment Lithuania | 142 Participants | 292 Participants | 150 Participants |
| Region of Enrollment Philippines | 902 Participants | 1800 Participants | 898 Participants |
| Region of Enrollment Poland | 147 Participants | 298 Participants | 151 Participants |
| Region of Enrollment Spain | 3 Participants | 5 Participants | 2 Participants |
| Region of Enrollment Thailand | 201 Participants | 400 Participants | 199 Participants |
| Sex: Female, Male Female | 1106 Participants | 2188 Participants | 1082 Participants |
| Sex: Female, Male Male | 1152 Participants | 2326 Participants | 1174 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | 0 / 2,258 | 1 / 2,255 |
| other Total, other adverse events | 871 / 2,258 | 963 / 2,255 |
| serious Total, serious adverse events | 25 / 2,258 | 30 / 2,255 |
Outcome results
Primary
Co-Primary: First Occurrence of Either RT-PCR- or Culture-confirmed Influenza (Time-to-event Analyses) Due to Any Influenza Type A or B Strain Regardless of Antigenic Match to the Strains Selected for the Seasonal Vaccine in Subjects ≥3 to <18 Years
The co-primary efficacy endpoint: was defined as the time from the last study vaccination to the onset of the first occurrence of either RT-PCR- or culture-confirmed influenza (time-to-event analyses) due to any influenza Type A or B strain regardless of antigenic match to the strains selected for the seasonal vaccine, that occurred more than 14 days after the last vaccination until the end of the influenza season.Absolute vaccine efficacy of QIVc by first occurrence RT-PCR or culture confirmed influenza, due to any influenza Type A and B strain in subjects ≥3 years to \<18 years of age
Time frame: Day 14 to Day 180 or until the end of the influenza season, whichever is longer
Population: FAS Efficacy - All subjects in the All Enrolled Set who received at least one dose of study vaccine and were evaluated for efficacy from 14 days after the last vaccination.
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| QIVc (≥2 Years to <18 Years of Age) | Co-Primary: First Occurrence of Either RT-PCR- or Culture-confirmed Influenza (Time-to-event Analyses) Due to Any Influenza Type A or B Strain Regardless of Antigenic Match to the Strains Selected for the Seasonal Vaccine in Subjects ≥3 to <18 Years | 171 Number of cases |
| Non-Influenza Comparator Vaccine | Co-Primary: First Occurrence of Either RT-PCR- or Culture-confirmed Influenza (Time-to-event Analyses) Due to Any Influenza Type A or B Strain Regardless of Antigenic Match to the Strains Selected for the Seasonal Vaccine in Subjects ≥3 to <18 Years | 351 Number of cases |
Comparison: Statistical analysis title - Absolute Vaccine Efficacy, Any Strain Adjusted aVE for QIVc vs. comparator. Success criteria for the primary efficacy endpoint was met if the LL of the 2-sided 95% CI of the aVE estimate was greater than 30% (co-primary endpoint) using the protocol definition of ILI for the entire age range (≥ 3 to \<18 years of age).95% CI: [44.8, 61.71]
Primary
Primary Efficacy: First Occurrence of Either RT-PCR- or Culture-confirmed Influenza (Time-to-event Analyses) Due to Any Influenza Type A or B Strain Regardless of Antigenic Match to the Strains Selected for the Seasonal Vaccine in Subjects ≥2 to <18 Years
The primary efficacy endpoint was defined as the time from the last study vaccination to the onset of the first occurrence of either RT-PCR- or culture-confirmed influenza (time-to-event analyses) due to any influenza Type A or B strain regardless of antigenic match to the strains selected for the seasonal vaccine, that occurred more than 14 days after the last vaccination until the end of the influenza season. Dataset Used: FAS-Efficacy = All subjects in the All Enrolled Set who received at least one dose of study vaccine and were evaluated for efficacy from 14 days after the last vaccination. The success criterion used for this primary objective was as follows: The efficacy of the QIVc was demonstrated if the lower limit (LL) of the 2-sided 95% confidence interval (CI) for VE was above 20%.
Time frame: Day 14 to Day 180 or until the end of the influenza season, whichever is longer
Population: FAS Efficacy - All subjects in the All Enrolled Set who received at least one dose of study vaccine and were evaluated for efficacy from 14 days after the last vaccination.
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| QIVc (≥2 Years to <18 Years of Age) | Primary Efficacy: First Occurrence of Either RT-PCR- or Culture-confirmed Influenza (Time-to-event Analyses) Due to Any Influenza Type A or B Strain Regardless of Antigenic Match to the Strains Selected for the Seasonal Vaccine in Subjects ≥2 to <18 Years | 175 Number of cases |
| Non-Influenza Comparator Vaccine | Primary Efficacy: First Occurrence of Either RT-PCR- or Culture-confirmed Influenza (Time-to-event Analyses) Due to Any Influenza Type A or B Strain Regardless of Antigenic Match to the Strains Selected for the Seasonal Vaccine in Subjects ≥2 to <18 Years | 364 Number of cases |
Comparison: Statistical Analysis title - Absolute Vaccine Efficacy Any Strain. Adjusted aVE for QIVc vs. comparator. Success criteria for the primary efficacy endpoint was met if the LL of the 2-sided 95% CI of the aVE estimate was greater than 20% (primary endpoint) using the protocol definition of ILI for the entire age range (2 to \<18 years of age).95% CI: [45.67, 62.12]
Secondary
ISecondary Immunogenicity: Percentage of Subjects Achieving Seroconversion for 4 Influenza Strains (HI Assay)
Immunogenicity was characterized by HI assay 3 weeks after the last vaccination in a subset of subjects 2 to \<9 years of age enrolled in Season 2 (n=432) and Season 3 (n=319) who were immunized and had immunogenicity data at the assessed timepoints (FAS Immunogenicity). Immunogenicity was assessed at baseline (Day 1; all subjects in immunogenicity subset), at Day 22 (all previously vaccinated subjects receiving a single dose of the study vaccine), and at Days 29 and 50 (all not previously vaccinated subjects receiving 2 doses) for all 4 influenza strains using the HI assay. Seroconversion was defined as: either a prevaccination HI titer \<1:10 and a postvaccination HI titer ≥1:40 or a prevaccination HI titer ≥1:10 and a ≥4 fold increase in postvaccination HI titer) Dataset used: FAS Immunogenicity = All subjects in the All Enrolled Set who received at least one dose of study vaccine and provided evaluable serum samples at both baseline and after the last vaccination.
Time frame: Day 22 (all previously vaccinated subjects) or Day 29 and Day 50 (all not previously vaccinated subjects)
Population: FAS Immunogenicity: all subjects in the All Enrolled Set who received at least one dose of study vaccine and provided evaluable serum samples at both baseline and after the last vaccination.
| Arm | Measure | Group | Value (NUMBER) |
|---|---|---|---|
| QIVc (≥2 Years to <18 Years of Age) | ISecondary Immunogenicity: Percentage of Subjects Achieving Seroconversion for 4 Influenza Strains (HI Assay) | A/H1N1 | 59.5 Percentage of participants |
| QIVc (≥2 Years to <18 Years of Age) | ISecondary Immunogenicity: Percentage of Subjects Achieving Seroconversion for 4 Influenza Strains (HI Assay) | A/H3N2 | 19.0 Percentage of participants |
| QIVc (≥2 Years to <18 Years of Age) | ISecondary Immunogenicity: Percentage of Subjects Achieving Seroconversion for 4 Influenza Strains (HI Assay) | B/Victoria | 40.0 Percentage of participants |
| QIVc (≥2 Years to <18 Years of Age) | ISecondary Immunogenicity: Percentage of Subjects Achieving Seroconversion for 4 Influenza Strains (HI Assay) | B/Yamagata | 49.5 Percentage of participants |
| Non-Influenza Comparator Vaccine | ISecondary Immunogenicity: Percentage of Subjects Achieving Seroconversion for 4 Influenza Strains (HI Assay) | A/H3N2 | 1.9 Percentage of participants |
| Non-Influenza Comparator Vaccine | ISecondary Immunogenicity: Percentage of Subjects Achieving Seroconversion for 4 Influenza Strains (HI Assay) | B/Victoria | 2.9 Percentage of participants |
| Non-Influenza Comparator Vaccine | ISecondary Immunogenicity: Percentage of Subjects Achieving Seroconversion for 4 Influenza Strains (HI Assay) | B/Yamagata | 4.8 Percentage of participants |
| Non-Influenza Comparator Vaccine | ISecondary Immunogenicity: Percentage of Subjects Achieving Seroconversion for 4 Influenza Strains (HI Assay) | A/H1N1 | 1.9 Percentage of participants |
| QIVc (≥2 Years to <9 Years of Age) | ISecondary Immunogenicity: Percentage of Subjects Achieving Seroconversion for 4 Influenza Strains (HI Assay) | B/Victoria | 58.4 Percentage of participants |
| QIVc (≥2 Years to <9 Years of Age) | ISecondary Immunogenicity: Percentage of Subjects Achieving Seroconversion for 4 Influenza Strains (HI Assay) | A/H3N2 | 51.9 Percentage of participants |
| QIVc (≥2 Years to <9 Years of Age) | ISecondary Immunogenicity: Percentage of Subjects Achieving Seroconversion for 4 Influenza Strains (HI Assay) | B/Yamagata | 58.4 Percentage of participants |
| QIVc (≥2 Years to <9 Years of Age) | ISecondary Immunogenicity: Percentage of Subjects Achieving Seroconversion for 4 Influenza Strains (HI Assay) | A/H1N1 | 74.0 Percentage of participants |
| Comparator (≥2 Years to <9 Years of Age) | ISecondary Immunogenicity: Percentage of Subjects Achieving Seroconversion for 4 Influenza Strains (HI Assay) | B/Yamagata | 1.4 Percentage of participants |
| Comparator (≥2 Years to <9 Years of Age) | ISecondary Immunogenicity: Percentage of Subjects Achieving Seroconversion for 4 Influenza Strains (HI Assay) | A/H3N2 | 1.4 Percentage of participants |
| Comparator (≥2 Years to <9 Years of Age) | ISecondary Immunogenicity: Percentage of Subjects Achieving Seroconversion for 4 Influenza Strains (HI Assay) | A/H1N1 | 6.2 Percentage of participants |
| Comparator (≥2 Years to <9 Years of Age) | ISecondary Immunogenicity: Percentage of Subjects Achieving Seroconversion for 4 Influenza Strains (HI Assay) | B/Victoria | 3.4 Percentage of participants |
Secondary
Safety: Percentage of Subjects With Solicited Local and Systemic Adverse Events for 7 Days After Vaccination
The measures for assessing safety and tolerability were as follows: Percentage of subjects with solicited local and systemic adverse events (AEs) for 7 days after vaccination on Day 1 (for previously vaccinated subjects) or for 7 days after vaccination on Day 1 and Day 29 (for not previously vaccinated subjects) in the QIVc group and the non-influenza comparator vaccine group. Dataset used: Solicited Safety Set
Time frame: days after vaccination on Day 1 (for previously vaccinated subjects) or for 7 days after vaccination on Day 1 and Day 29 (for not previously vaccinated subjects)
Population: Dataset used: Solicited Safety Set = All subjects in the Exposed Set who had gone through any assessment of local and systemic site reaction and/or assessment of any use of analgesics/antipyretics.~Note: Other solicited adverse events refer to use of analgesics / antipyretics for prophylaxis or treatment.
| Arm | Measure | Group | Value (NUMBER) |
|---|---|---|---|
| QIVc (≥2 Years to <18 Years of Age) | Safety: Percentage of Subjects With Solicited Local and Systemic Adverse Events for 7 Days After Vaccination | Solicited AEs | 51.4 Percentage of participants |
| QIVc (≥2 Years to <18 Years of Age) | Safety: Percentage of Subjects With Solicited Local and Systemic Adverse Events for 7 Days After Vaccination | Solicited Local AEs | 36.8 Percentage of participants |
| QIVc (≥2 Years to <18 Years of Age) | Safety: Percentage of Subjects With Solicited Local and Systemic Adverse Events for 7 Days After Vaccination | Other | 8.6 Percentage of participants |
| QIVc (≥2 Years to <18 Years of Age) | Safety: Percentage of Subjects With Solicited Local and Systemic Adverse Events for 7 Days After Vaccination | Solicited Systemic AEs | 31.4 Percentage of participants |
| Non-Influenza Comparator Vaccine | Safety: Percentage of Subjects With Solicited Local and Systemic Adverse Events for 7 Days After Vaccination | Other | 7.3 Percentage of participants |
| Non-Influenza Comparator Vaccine | Safety: Percentage of Subjects With Solicited Local and Systemic Adverse Events for 7 Days After Vaccination | Solicited AEs | 48.6 Percentage of participants |
| Non-Influenza Comparator Vaccine | Safety: Percentage of Subjects With Solicited Local and Systemic Adverse Events for 7 Days After Vaccination | Solicited Local AEs | 33.6 Percentage of participants |
| Non-Influenza Comparator Vaccine | Safety: Percentage of Subjects With Solicited Local and Systemic Adverse Events for 7 Days After Vaccination | Solicited Systemic AEs | 30.5 Percentage of participants |
Secondary
Safety: Percentage of Subjects With Unsolicited AEs for 21 Days After Vaccination
The measures for assessing safety and tolerability were as follows: Percentage of subjects with unsolicited AEs assessed from Day 1 to Day 22 (for previously vaccinated subjects) or from Day 1 to Day 50 (for not previously vaccinated subjects) in the QIVc group and the non-influenza comparator vaccine group. Dataset used: Unsolicited Safety Set (Unsolicited Adverse Events)
Time frame: Day 1 to Day 22 (for previously vaccinated subjects) or Day 1 to Day 50 (for not previously vaccinated subjects)
Population: Dataset used: unsolicited Safety Set defined as all subjects in the Exposed Set who had gone through any AE assessments, ie, a subject did not have to have any AEs to be included in this population
| Arm | Measure | Group | Value (NUMBER) |
|---|---|---|---|
| QIVc (≥2 Years to <18 Years of Age) | Safety: Percentage of Subjects With Unsolicited AEs for 21 Days After Vaccination | Related AE | 4.3 Percentage of participants |
| QIVc (≥2 Years to <18 Years of Age) | Safety: Percentage of Subjects With Unsolicited AEs for 21 Days After Vaccination | Any AE (Moderate) | 4.8 Percentage of participants |
| QIVc (≥2 Years to <18 Years of Age) | Safety: Percentage of Subjects With Unsolicited AEs for 21 Days After Vaccination | Any AE | 28.0 Percentage of participants |
| QIVc (≥2 Years to <18 Years of Age) | Safety: Percentage of Subjects With Unsolicited AEs for 21 Days After Vaccination | Any AE (Severe) | 0.5 Percentage of participants |
| QIVc (≥2 Years to <18 Years of Age) | Safety: Percentage of Subjects With Unsolicited AEs for 21 Days After Vaccination | Any AE (Mild) | 24.4 Percentage of participants |
| Non-Influenza Comparator Vaccine | Safety: Percentage of Subjects With Unsolicited AEs for 21 Days After Vaccination | Any AE (Severe) | 0.5 Percentage of participants |
| Non-Influenza Comparator Vaccine | Safety: Percentage of Subjects With Unsolicited AEs for 21 Days After Vaccination | Any AE (Mild) | 24.6 Percentage of participants |
| Non-Influenza Comparator Vaccine | Safety: Percentage of Subjects With Unsolicited AEs for 21 Days After Vaccination | Related AE | 3.9 Percentage of participants |
| Non-Influenza Comparator Vaccine | Safety: Percentage of Subjects With Unsolicited AEs for 21 Days After Vaccination | Any AE | 27.9 Percentage of participants |
| Non-Influenza Comparator Vaccine | Safety: Percentage of Subjects With Unsolicited AEs for 21 Days After Vaccination | Any AE (Moderate) | 4.5 Percentage of participants |
Secondary
Safety: Subjects With SAEs, AEs Leading to Withdrawal From Vaccination and/or the Study,(MAAEs) Within 30 Days of a 1st Occurrence, Post-ILI, and NOCDs Reported During Entire Study Participation or End of Flue Season, Whichever Was Longer
The measures for assessing safety and tolerability were as follows: Percentage of subjects with SAEs, AEs leading to withdrawal from vaccination and/or the study, Medically-Attended AEs (MAAEs) within 30 days after the first occurrence of an ILI, and New Onset of Chronic Diseases (NOCDs) reported during the subject's entire participation in the study (ie, from Day 1 to Day 181 \[for previously vaccinated subjects\] or from Day 1 to Day 209 \[for not previously vaccinated subjects\]), or until the end of influenza season, whichever was longer, and all medications associated with these events. Dataset used: Overall Safety Set
Time frame: Day 1 to Day 181 (for previously vaccinated subjects) or to Day 209 (for not previously vaccinated subjects)
Population: Dataset used: overall safety set defined as all subjects in the Solicited Safety Set and/or Unsolicited Safety Set. Subjects providing only 30 minutes postvaccination safety data were also reported separately in a 30-minute postvaccination safety analysis.
| Arm | Measure | Group | Value (NUMBER) |
|---|---|---|---|
| QIVc (≥2 Years to <18 Years of Age) | Safety: Subjects With SAEs, AEs Leading to Withdrawal From Vaccination and/or the Study,(MAAEs) Within 30 Days of a 1st Occurrence, Post-ILI, and NOCDs Reported During Entire Study Participation or End of Flue Season, Whichever Was Longer | SAE | 1.1 Percentage of participants |
| QIVc (≥2 Years to <18 Years of Age) | Safety: Subjects With SAEs, AEs Leading to Withdrawal From Vaccination and/or the Study,(MAAEs) Within 30 Days of a 1st Occurrence, Post-ILI, and NOCDs Reported During Entire Study Participation or End of Flue Season, Whichever Was Longer | Related SAE | 0 Percentage of participants |
| QIVc (≥2 Years to <18 Years of Age) | Safety: Subjects With SAEs, AEs Leading to Withdrawal From Vaccination and/or the Study,(MAAEs) Within 30 Days of a 1st Occurrence, Post-ILI, and NOCDs Reported During Entire Study Participation or End of Flue Season, Whichever Was Longer | MAAE | 27.2 Percentage of participants |
| QIVc (≥2 Years to <18 Years of Age) | Safety: Subjects With SAEs, AEs Leading to Withdrawal From Vaccination and/or the Study,(MAAEs) Within 30 Days of a 1st Occurrence, Post-ILI, and NOCDs Reported During Entire Study Participation or End of Flue Season, Whichever Was Longer | NOCD | 0.4 Percentage of participants |
| QIVc (≥2 Years to <18 Years of Age) | Safety: Subjects With SAEs, AEs Leading to Withdrawal From Vaccination and/or the Study,(MAAEs) Within 30 Days of a 1st Occurrence, Post-ILI, and NOCDs Reported During Entire Study Participation or End of Flue Season, Whichever Was Longer | Death | 0 Percentage of participants |
| QIVc (≥2 Years to <18 Years of Age) | Safety: Subjects With SAEs, AEs Leading to Withdrawal From Vaccination and/or the Study,(MAAEs) Within 30 Days of a 1st Occurrence, Post-ILI, and NOCDs Reported During Entire Study Participation or End of Flue Season, Whichever Was Longer | AE leading to study withdrawal | 0 Percentage of participants |
| Non-Influenza Comparator Vaccine | Safety: Subjects With SAEs, AEs Leading to Withdrawal From Vaccination and/or the Study,(MAAEs) Within 30 Days of a 1st Occurrence, Post-ILI, and NOCDs Reported During Entire Study Participation or End of Flue Season, Whichever Was Longer | MAAE | 30.1 Percentage of participants |
| Non-Influenza Comparator Vaccine | Safety: Subjects With SAEs, AEs Leading to Withdrawal From Vaccination and/or the Study,(MAAEs) Within 30 Days of a 1st Occurrence, Post-ILI, and NOCDs Reported During Entire Study Participation or End of Flue Season, Whichever Was Longer | SAE | 1.3 Percentage of participants |
| Non-Influenza Comparator Vaccine | Safety: Subjects With SAEs, AEs Leading to Withdrawal From Vaccination and/or the Study,(MAAEs) Within 30 Days of a 1st Occurrence, Post-ILI, and NOCDs Reported During Entire Study Participation or End of Flue Season, Whichever Was Longer | Death | 0.04 Percentage of participants |
| Non-Influenza Comparator Vaccine | Safety: Subjects With SAEs, AEs Leading to Withdrawal From Vaccination and/or the Study,(MAAEs) Within 30 Days of a 1st Occurrence, Post-ILI, and NOCDs Reported During Entire Study Participation or End of Flue Season, Whichever Was Longer | Related SAE | 0 Percentage of participants |
| Non-Influenza Comparator Vaccine | Safety: Subjects With SAEs, AEs Leading to Withdrawal From Vaccination and/or the Study,(MAAEs) Within 30 Days of a 1st Occurrence, Post-ILI, and NOCDs Reported During Entire Study Participation or End of Flue Season, Whichever Was Longer | AE leading to study withdrawal | 0 Percentage of participants |
| Non-Influenza Comparator Vaccine | Safety: Subjects With SAEs, AEs Leading to Withdrawal From Vaccination and/or the Study,(MAAEs) Within 30 Days of a 1st Occurrence, Post-ILI, and NOCDs Reported During Entire Study Participation or End of Flue Season, Whichever Was Longer | NOCD | 0.5 Percentage of participants |
Secondary
Secondary Efficacy #1: First Occurrence of Either RT-PCR- or Culture-confirmed Influenza Due to Any Influenza Type A or B Strain Regardless of Antigenic Match to the Strains Selected for the Seasonal Vaccine
The endpoint was defined as the time from the last study vaccination to the onset of the first occurrence of either RT-PCR- or culture-confirmed influenza due to any influenza Type A or B strain regardless of antigenic match to the strains selected for the seasonal vaccine, that occurred more than 14 days after the last vaccination until the end of the influenza season in subjects 2 to \<18 years, 2 to \<9 years, 4 to \<18 years, and 9 to \<18 years. Dataset used: FAS Efficacy = All subjects in the All Enrolled Set who received at least one dose of study vaccine and were evaluated for efficacy from 14 days after the last vaccination.
Time frame: Day 14 to Day 180 or until the end of the influenza season, whichever is longer.
Population: FAS Efficacy = All subjects in the All Enrolled Set who received at least one dose of study vaccine and were evaluated for efficacy from 14 days after the last vaccination.
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| QIVc (≥2 Years to <18 Years of Age) | Secondary Efficacy #1: First Occurrence of Either RT-PCR- or Culture-confirmed Influenza Due to Any Influenza Type A or B Strain Regardless of Antigenic Match to the Strains Selected for the Seasonal Vaccine | 175 Number of cases |
| Non-Influenza Comparator Vaccine | Secondary Efficacy #1: First Occurrence of Either RT-PCR- or Culture-confirmed Influenza Due to Any Influenza Type A or B Strain Regardless of Antigenic Match to the Strains Selected for the Seasonal Vaccine | 364 Number of cases |
| QIVc (≥2 Years to <9 Years of Age) | Secondary Efficacy #1: First Occurrence of Either RT-PCR- or Culture-confirmed Influenza Due to Any Influenza Type A or B Strain Regardless of Antigenic Match to the Strains Selected for the Seasonal Vaccine | 123 Number of cases |
| Comparator (≥2 Years to <9 Years of Age) | Secondary Efficacy #1: First Occurrence of Either RT-PCR- or Culture-confirmed Influenza Due to Any Influenza Type A or B Strain Regardless of Antigenic Match to the Strains Selected for the Seasonal Vaccine | 234 Number of cases |
| QIVc (≥4 Years to <18 Years of Age) | Secondary Efficacy #1: First Occurrence of Either RT-PCR- or Culture-confirmed Influenza Due to Any Influenza Type A or B Strain Regardless of Antigenic Match to the Strains Selected for the Seasonal Vaccine | 154 Number of cases |
| Comparator (≥4 Years to <18 Years of Age) | Secondary Efficacy #1: First Occurrence of Either RT-PCR- or Culture-confirmed Influenza Due to Any Influenza Type A or B Strain Regardless of Antigenic Match to the Strains Selected for the Seasonal Vaccine | 310 Number of cases |
| QIVc (≥9 Years to <18 Years of Age) | Secondary Efficacy #1: First Occurrence of Either RT-PCR- or Culture-confirmed Influenza Due to Any Influenza Type A or B Strain Regardless of Antigenic Match to the Strains Selected for the Seasonal Vaccine | 52 Number of cases |
| Comparator (≥9 Years to <18 Years of Age) | Secondary Efficacy #1: First Occurrence of Either RT-PCR- or Culture-confirmed Influenza Due to Any Influenza Type A or B Strain Regardless of Antigenic Match to the Strains Selected for the Seasonal Vaccine | 130 Number of cases |
Comparison: Statistical analysis title Absolute Vaccine Efficacy, Any Strain, 2 to \<18yrs95% CI: [45.67, 62.12]
Comparison: Statistical analysis title: Absolute Vaccine Efficacy, Any Strain, 2 to \<9yrs95% CI: [38.43, 60.22]
Comparison: Statistical analysis title: Absolute Vaccine Efficacy, Any Strain, 4 to \<18yrs95% CI: [43.38, 61.54]
Comparison: Statistical analysis title Absolute Vaccine Efficacy, Any Strain, 9 to \<18yrs95% CI: [47.37, 72.34]
Secondary
Secondary Efficacy #2: First Occurrence of RT-PCR-confirmed Influenza Due to Any Influenza Type A or B Strain Regardless of Antigenic Match to the Strains Selected for the Seasonal Vaccine
The endpoint was defined as the time from the last study vaccination to the onset of the first occurrence of RT-PCR-confirmed influenza due to any influenza Type A or B strain regardless of antigenic match to the strains selected for the seasonal vaccine, that occurred more than 14 days after the last vaccination until the end of the influenza season in subjects 2 to \<18 years, 2 to \<9 years, 4 to \<18 years, and 9 to \<18 years Dataset used: FAS Efficacy - All subjects in the All Enrolled Set who received at least one dose of study vaccine and were evaluated for efficacy from 14 days after the last vaccination.
Time frame: Day 14 to Day 180 or until the end of the influenza season, whichever is longer.
Population: FAS-Efficacy = All subjects in the All Enrolled Set who received at least one dose of study vaccine and were evaluated for efficacy from 14 days after the last vaccination.
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| QIVc (≥2 Years to <18 Years of Age) | Secondary Efficacy #2: First Occurrence of RT-PCR-confirmed Influenza Due to Any Influenza Type A or B Strain Regardless of Antigenic Match to the Strains Selected for the Seasonal Vaccine | 175 Number of cases |
| Non-Influenza Comparator Vaccine | Secondary Efficacy #2: First Occurrence of RT-PCR-confirmed Influenza Due to Any Influenza Type A or B Strain Regardless of Antigenic Match to the Strains Selected for the Seasonal Vaccine | 364 Number of cases |
| QIVc (≥2 Years to <9 Years of Age) | Secondary Efficacy #2: First Occurrence of RT-PCR-confirmed Influenza Due to Any Influenza Type A or B Strain Regardless of Antigenic Match to the Strains Selected for the Seasonal Vaccine | 123 Number of cases |
| Comparator (≥2 Years to <9 Years of Age) | Secondary Efficacy #2: First Occurrence of RT-PCR-confirmed Influenza Due to Any Influenza Type A or B Strain Regardless of Antigenic Match to the Strains Selected for the Seasonal Vaccine | 234 Number of cases |
| QIVc (≥4 Years to <18 Years of Age) | Secondary Efficacy #2: First Occurrence of RT-PCR-confirmed Influenza Due to Any Influenza Type A or B Strain Regardless of Antigenic Match to the Strains Selected for the Seasonal Vaccine | 154 Number of cases |
| Comparator (≥4 Years to <18 Years of Age) | Secondary Efficacy #2: First Occurrence of RT-PCR-confirmed Influenza Due to Any Influenza Type A or B Strain Regardless of Antigenic Match to the Strains Selected for the Seasonal Vaccine | 310 Number of cases |
| QIVc (≥9 Years to <18 Years of Age) | Secondary Efficacy #2: First Occurrence of RT-PCR-confirmed Influenza Due to Any Influenza Type A or B Strain Regardless of Antigenic Match to the Strains Selected for the Seasonal Vaccine | 52 Number of cases |
| Comparator (≥9 Years to <18 Years of Age) | Secondary Efficacy #2: First Occurrence of RT-PCR-confirmed Influenza Due to Any Influenza Type A or B Strain Regardless of Antigenic Match to the Strains Selected for the Seasonal Vaccine | 130 Number of cases |
Comparison: Statistical analysis title Absolute Vaccine Efficacy, Any Strain, 2 to \<18yrs95% CI: [45.67, 62.12]
Comparison: Statistical analysis title Absolute Vaccine Efficacy, Any Strain, 2 to \<9yrs95% CI: [49.01, 69.83]
Comparison: Statistical analysis title Absolute Vaccine Efficacy, Any Strain, 4 to \<18yrs95% CI: [49.08, 68.05]
Comparison: Statistical analysis title Absolute Vaccine Efficacy, Any Strain, 9 to \<18yrs95% CI: [42.14, 73.33]
Secondary
Secondary Efficacy #3: First Occurrence of Culture-confirmed Influenza Due to Any Influenza Type A or B Strain Regardless of Antigenic Match to the Strains Selected for the Seasonal Vaccine
The secondary endpoint was defined as the time from the last study vaccination to the onset of the first occurrence of culture-confirmed influenza due to any influenza Type A or B strain regardless of antigenic match to the strains selected for the seasonal vaccine, that occurred more than 14 days after the last vaccination until the end of the influenza season in subjects 2 to \<18 years, 2 to \<9 years, 4 to \<18 years, and 9 to \<18 years. Dataset used: FAS Efficacy
Time frame: Day 14 to Day 180 or until the end of the influenza season, whichever is longer.
Population: FAS-Efficacy = All subjects in the All Enrolled Set who received at least one dose of study vaccine and were evaluated for efficacy from 14 days after the last vaccination.
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| QIVc (≥2 Years to <18 Years of Age) | Secondary Efficacy #3: First Occurrence of Culture-confirmed Influenza Due to Any Influenza Type A or B Strain Regardless of Antigenic Match to the Strains Selected for the Seasonal Vaccine | 115 Number of cases |
| Non-Influenza Comparator Vaccine | Secondary Efficacy #3: First Occurrence of Culture-confirmed Influenza Due to Any Influenza Type A or B Strain Regardless of Antigenic Match to the Strains Selected for the Seasonal Vaccine | 279 Number of cases |
| QIVc (≥2 Years to <9 Years of Age) | Secondary Efficacy #3: First Occurrence of Culture-confirmed Influenza Due to Any Influenza Type A or B Strain Regardless of Antigenic Match to the Strains Selected for the Seasonal Vaccine | 79 Number of cases |
| Comparator (≥2 Years to <9 Years of Age) | Secondary Efficacy #3: First Occurrence of Culture-confirmed Influenza Due to Any Influenza Type A or B Strain Regardless of Antigenic Match to the Strains Selected for the Seasonal Vaccine | 190 Number of cases |
| QIVc (≥4 Years to <18 Years of Age) | Secondary Efficacy #3: First Occurrence of Culture-confirmed Influenza Due to Any Influenza Type A or B Strain Regardless of Antigenic Match to the Strains Selected for the Seasonal Vaccine | 101 Number of cases |
| Comparator (≥4 Years to <18 Years of Age) | Secondary Efficacy #3: First Occurrence of Culture-confirmed Influenza Due to Any Influenza Type A or B Strain Regardless of Antigenic Match to the Strains Selected for the Seasonal Vaccine | 237 Number of cases |
| QIVc (≥9 Years to <18 Years of Age) | Secondary Efficacy #3: First Occurrence of Culture-confirmed Influenza Due to Any Influenza Type A or B Strain Regardless of Antigenic Match to the Strains Selected for the Seasonal Vaccine | 36 Number of cases |
| Comparator (≥9 Years to <18 Years of Age) | Secondary Efficacy #3: First Occurrence of Culture-confirmed Influenza Due to Any Influenza Type A or B Strain Regardless of Antigenic Match to the Strains Selected for the Seasonal Vaccine | 89 Number of cases |
Comparison: Statistical analysis title Absolute Vaccine Efficacy, Any Strain, 2 to \<18yrs95% CI: [51.3, 68.46]
Comparison: Statistical analysis title Absolute Vaccine Efficacy, Any Strain, 2 to \<9yrs95% CI: [49.01, 69.83]
Comparison: Statistical analysis title Absolute Vaccine Efficacy, Any Strain, 9 to \<18yrs95% CI: [49.08, 68.05]
Comparison: Statistical analysis title Absolute Vaccine Efficacy, Any Strain, 9 to \<18yrs95% CI: [42.14, 73.33]
Secondary
Secondary Efficacy #4: First Occurrence of Culture-confirmed Influenza Due to Influenza Type A or B Strain Antigenically Matched to the Strains Selected for the Seasonal Vaccine
The endpoint was defined as the time from the last study vaccination to the onset of the first occurrence of culture-confirmed influenza due to influenza Type A or B strain antigenically matched to the strains selected for the seasonal vaccine, that occurred more than 14 days after the last vaccination until the end of the influenza season in subjects 2 to \<18 years, 2 to \<9 years, 4 to \<18 years, and 9 to \<18 years.
Time frame: Day 14 to Day 180 or until the end of the influenza season, whichever is longer.
Population: FAS-Efficacy = All subjects in the All Enrolled Set who received at least one dose of study vaccine and were evaluated for efficacy from 14 days after the last vaccination.
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| QIVc (≥2 Years to <18 Years of Age) | Secondary Efficacy #4: First Occurrence of Culture-confirmed Influenza Due to Influenza Type A or B Strain Antigenically Matched to the Strains Selected for the Seasonal Vaccine | 90 Number of cases |
| Non-Influenza Comparator Vaccine | Secondary Efficacy #4: First Occurrence of Culture-confirmed Influenza Due to Influenza Type A or B Strain Antigenically Matched to the Strains Selected for the Seasonal Vaccine | 236 Number of cases |
| QIVc (≥2 Years to <9 Years of Age) | Secondary Efficacy #4: First Occurrence of Culture-confirmed Influenza Due to Influenza Type A or B Strain Antigenically Matched to the Strains Selected for the Seasonal Vaccine | 64 Number of cases |
| Comparator (≥2 Years to <9 Years of Age) | Secondary Efficacy #4: First Occurrence of Culture-confirmed Influenza Due to Influenza Type A or B Strain Antigenically Matched to the Strains Selected for the Seasonal Vaccine | 164 Number of cases |
| QIVc (≥4 Years to <18 Years of Age) | Secondary Efficacy #4: First Occurrence of Culture-confirmed Influenza Due to Influenza Type A or B Strain Antigenically Matched to the Strains Selected for the Seasonal Vaccine | 81 Number of cases |
| Comparator (≥4 Years to <18 Years of Age) | Secondary Efficacy #4: First Occurrence of Culture-confirmed Influenza Due to Influenza Type A or B Strain Antigenically Matched to the Strains Selected for the Seasonal Vaccine | 200 Number of cases |
| QIVc (≥9 Years to <18 Years of Age) | Secondary Efficacy #4: First Occurrence of Culture-confirmed Influenza Due to Influenza Type A or B Strain Antigenically Matched to the Strains Selected for the Seasonal Vaccine | 26 Number of cases |
| Comparator (≥9 Years to <18 Years of Age) | Secondary Efficacy #4: First Occurrence of Culture-confirmed Influenza Due to Influenza Type A or B Strain Antigenically Matched to the Strains Selected for the Seasonal Vaccine | 72 Number of cases |
Comparison: Statistical analysis title Absolute Vaccine Efficacy, Any Strain, 2 to \<18yrs95% CI: [53.64, 71.48]
Comparison: Statistical analysis title Absolute Vaccine Efficacy, Any Strain, 2 to \<9yrs95% CI: [50.66, 72.32]
Comparison: Statistical analysis title Absolute Vaccine Efficacy, Any Strain, 4 to \<18yrs95% CI: [50.25, 70.53]
Comparison: Statistical analysis title Absolute Vaccine Efficacy, Any Strain, 9 to \<18yrs95% CI: [44.84, 77.51]
Secondary
Secondary Immunogenicity: Geometric Mean Ratio for 4 Influenza Strains (HI Assay)
Immunogenicity was characterized by HI assay 3 weeks after the last vaccination in a subset of subjects 2 to \<9 years of age enrolled in Season 2 (n=432) and Season 3 (n=319) who were immunized and had immunogenicity data at the assessed timepoints (FAS Immunogenicity). Immunogenicity was assessed at baseline (Day 1; all subjects in immunogenicity subset), at Day 22 (all previously vaccinated subjects receiving a single dose of the study vaccine), and at Days 29 and 50 (all not previously vaccinated subjects receiving 2 doses) for all 4 influenza strains using the HI assay. Geometric mean ratios (GMRs) measure the ratio in immunogenicity titers within subject\\ Dataset used: FAS Immunogenicity = All subjects in the All Enrolled Set who received at least one dose of study vaccine and provided evaluable serum samples at both baseline and after the last vaccination.
Time frame: Day 22/Day 1 (all previously vaccinated subjects) or Day 29/Day 1 and Day 50/Day 1 (all not previously vaccinated subjects receiving 2 doses)
Population: FAS Immunogenicity: all subjects in the All Enrolled Set who received at least one dose of study vaccine and provided evaluable serum samples at both baseline and after the last vaccination.
| Arm | Measure | Group | Value (NUMBER) |
|---|---|---|---|
| QIVc (≥2 Years to <18 Years of Age) | Secondary Immunogenicity: Geometric Mean Ratio for 4 Influenza Strains (HI Assay) | A/H3N2 | 1.74 Geometric mean ratio (GMR) |
| QIVc (≥2 Years to <18 Years of Age) | Secondary Immunogenicity: Geometric Mean Ratio for 4 Influenza Strains (HI Assay) | A/H1N1 | 5.76 Geometric mean ratio (GMR) |
| QIVc (≥2 Years to <18 Years of Age) | Secondary Immunogenicity: Geometric Mean Ratio for 4 Influenza Strains (HI Assay) | B/Yamagata | 4.63 Geometric mean ratio (GMR) |
| QIVc (≥2 Years to <18 Years of Age) | Secondary Immunogenicity: Geometric Mean Ratio for 4 Influenza Strains (HI Assay) | B/Victoria | 3.79 Geometric mean ratio (GMR) |
| Non-Influenza Comparator Vaccine | Secondary Immunogenicity: Geometric Mean Ratio for 4 Influenza Strains (HI Assay) | A/H3N2 | 0.99 Geometric mean ratio (GMR) |
| Non-Influenza Comparator Vaccine | Secondary Immunogenicity: Geometric Mean Ratio for 4 Influenza Strains (HI Assay) | B/Yamagata | 1.08 Geometric mean ratio (GMR) |
| Non-Influenza Comparator Vaccine | Secondary Immunogenicity: Geometric Mean Ratio for 4 Influenza Strains (HI Assay) | A/H1N1 | 1.00 Geometric mean ratio (GMR) |
| Non-Influenza Comparator Vaccine | Secondary Immunogenicity: Geometric Mean Ratio for 4 Influenza Strains (HI Assay) | B/Victoria | 1.00 Geometric mean ratio (GMR) |
| QIVc (≥2 Years to <9 Years of Age) | Secondary Immunogenicity: Geometric Mean Ratio for 4 Influenza Strains (HI Assay) | A/H3N2 | 4.14 Geometric mean ratio (GMR) |
| QIVc (≥2 Years to <9 Years of Age) | Secondary Immunogenicity: Geometric Mean Ratio for 4 Influenza Strains (HI Assay) | B/Victoria | 7.01 Geometric mean ratio (GMR) |
| QIVc (≥2 Years to <9 Years of Age) | Secondary Immunogenicity: Geometric Mean Ratio for 4 Influenza Strains (HI Assay) | B/Yamagata | 5.27 Geometric mean ratio (GMR) |
| QIVc (≥2 Years to <9 Years of Age) | Secondary Immunogenicity: Geometric Mean Ratio for 4 Influenza Strains (HI Assay) | A/H1N1 | 9.73 Geometric mean ratio (GMR) |
| Comparator (≥2 Years to <9 Years of Age) | Secondary Immunogenicity: Geometric Mean Ratio for 4 Influenza Strains (HI Assay) | A/H1N1 | 1.23 Geometric mean ratio (GMR) |
| Comparator (≥2 Years to <9 Years of Age) | Secondary Immunogenicity: Geometric Mean Ratio for 4 Influenza Strains (HI Assay) | B/Yamagata | 1.05 Geometric mean ratio (GMR) |
| Comparator (≥2 Years to <9 Years of Age) | Secondary Immunogenicity: Geometric Mean Ratio for 4 Influenza Strains (HI Assay) | B/Victoria | 1.25 Geometric mean ratio (GMR) |
| Comparator (≥2 Years to <9 Years of Age) | Secondary Immunogenicity: Geometric Mean Ratio for 4 Influenza Strains (HI Assay) | A/H3N2 | 1.02 Geometric mean ratio (GMR) |
Secondary
Secondary Immunogenicity: Geometric Mean Titers for 4 Influenza Strains (HI Assay)
Immunogenicity was characterized by HI assay 3 weeks after the last vaccination in a subset of subjects 2 to \<9 years of age enrolled in Season 2 (n=432) and Season 3 (n=319) who were immunized and had immunogenicity data at the assessed timepoints (FAS Immunogenicity). Immunogenicity was assessed at baseline (Day 1; all subjects in immunogenicity subset), at Day 22 (all previously vaccinated subjects receiving a single dose of the study vaccine), and at Days 29 and 50 (all not previously vaccinated subjects receiving 2 doses) for all 4 influenza strains using the HI assay.
Time frame: Day 1 (all subjects), Day 22 (all previously vaccinated subjects) or Day 29 and Day 50 (all not previously vaccinated subjects receiving 2 doses)
Population: FAS Immunogenicity - All Subjects in the All Enrolled Set who received at least one dose of study vaccine and provided evaluable serum samples at both baseline at after the last vaccination
| Arm | Measure | Group | Value (NUMBER) |
|---|---|---|---|
| QIVc (≥2 Years to <18 Years of Age) | Secondary Immunogenicity: Geometric Mean Titers for 4 Influenza Strains (HI Assay) | B/Yamagata Day 1 HI GMT | 10.87 Geometric mean titers (GMTs) |
| QIVc (≥2 Years to <18 Years of Age) | Secondary Immunogenicity: Geometric Mean Titers for 4 Influenza Strains (HI Assay) | B/Victoria Day 1 HI GMT | 11.67 Geometric mean titers (GMTs) |
| QIVc (≥2 Years to <18 Years of Age) | Secondary Immunogenicity: Geometric Mean Titers for 4 Influenza Strains (HI Assay) | A/H3N2 Day 22/50 HI GMT | 168.73 Geometric mean titers (GMTs) |
| QIVc (≥2 Years to <18 Years of Age) | Secondary Immunogenicity: Geometric Mean Titers for 4 Influenza Strains (HI Assay) | A/H1N1 Day 22/50 HI GMT | 283.45 Geometric mean titers (GMTs) |
| QIVc (≥2 Years to <18 Years of Age) | Secondary Immunogenicity: Geometric Mean Titers for 4 Influenza Strains (HI Assay) | B/Yamagata Day 22/50 HI GMT | 52.81 Geometric mean titers (GMTs) |
| QIVc (≥2 Years to <18 Years of Age) | Secondary Immunogenicity: Geometric Mean Titers for 4 Influenza Strains (HI Assay) | B/Victoria Day 22/50 HI GMT | 45.25 Geometric mean titers (GMTs) |
| QIVc (≥2 Years to <18 Years of Age) | Secondary Immunogenicity: Geometric Mean Titers for 4 Influenza Strains (HI Assay) | A/H3N2 Day 1 HI GMT | 97.02 Geometric mean titers (GMTs) |
| QIVc (≥2 Years to <18 Years of Age) | Secondary Immunogenicity: Geometric Mean Titers for 4 Influenza Strains (HI Assay) | A/H1N1 Day 1 HI GMT | 50.83 Geometric mean titers (GMTs) |
| Non-Influenza Comparator Vaccine | Secondary Immunogenicity: Geometric Mean Titers for 4 Influenza Strains (HI Assay) | B/Victoria Day 22/50 HI GMT | 11.94 Geometric mean titers (GMTs) |
| Non-Influenza Comparator Vaccine | Secondary Immunogenicity: Geometric Mean Titers for 4 Influenza Strains (HI Assay) | B/Yamagata Day 1 HI GMT | 12.17 Geometric mean titers (GMTs) |
| Non-Influenza Comparator Vaccine | Secondary Immunogenicity: Geometric Mean Titers for 4 Influenza Strains (HI Assay) | A/H1N1 Day 1 HI GMT | 47.51 Geometric mean titers (GMTs) |
| Non-Influenza Comparator Vaccine | Secondary Immunogenicity: Geometric Mean Titers for 4 Influenza Strains (HI Assay) | B/Yamagata Day 22/50 HI GMT | 12.34 Geometric mean titers (GMTs) |
| Non-Influenza Comparator Vaccine | Secondary Immunogenicity: Geometric Mean Titers for 4 Influenza Strains (HI Assay) | A/H3N2 Day 1 HI GMT | 94.40 Geometric mean titers (GMTs) |
| Non-Influenza Comparator Vaccine | Secondary Immunogenicity: Geometric Mean Titers for 4 Influenza Strains (HI Assay) | B/Victoria Day 1 HI GMT | 11.73 Geometric mean titers (GMTs) |
| Non-Influenza Comparator Vaccine | Secondary Immunogenicity: Geometric Mean Titers for 4 Influenza Strains (HI Assay) | A/H1N1 Day 22/50 HI GMT | 49.20 Geometric mean titers (GMTs) |
| Non-Influenza Comparator Vaccine | Secondary Immunogenicity: Geometric Mean Titers for 4 Influenza Strains (HI Assay) | A/H3N2 Day 22/50 HI GMT | 96.27 Geometric mean titers (GMTs) |
| QIVc (≥2 Years to <9 Years of Age) | Secondary Immunogenicity: Geometric Mean Titers for 4 Influenza Strains (HI Assay) | B/Victoria Day 22/50 HI GMT | 66.82 Geometric mean titers (GMTs) |
| QIVc (≥2 Years to <9 Years of Age) | Secondary Immunogenicity: Geometric Mean Titers for 4 Influenza Strains (HI Assay) | A/H1N1 Day 1 HI GMT | 36.62 Geometric mean titers (GMTs) |
| QIVc (≥2 Years to <9 Years of Age) | Secondary Immunogenicity: Geometric Mean Titers for 4 Influenza Strains (HI Assay) | A/H1N1 Day 22/50 HI GMT | 380.70 Geometric mean titers (GMTs) |
| QIVc (≥2 Years to <9 Years of Age) | Secondary Immunogenicity: Geometric Mean Titers for 4 Influenza Strains (HI Assay) | A/H3N2 Day 22/50 HI GMT | 67.64 Geometric mean titers (GMTs) |
| QIVc (≥2 Years to <9 Years of Age) | Secondary Immunogenicity: Geometric Mean Titers for 4 Influenza Strains (HI Assay) | B/Victoria Day 1 HI GMT | 9.54 Geometric mean titers (GMTs) |
| QIVc (≥2 Years to <9 Years of Age) | Secondary Immunogenicity: Geometric Mean Titers for 4 Influenza Strains (HI Assay) | B/Yamagata Day 1 HI GMT | 23.98 Geometric mean titers (GMTs) |
| QIVc (≥2 Years to <9 Years of Age) | Secondary Immunogenicity: Geometric Mean Titers for 4 Influenza Strains (HI Assay) | B/Yamagata Day 22/50 HI GMT | 108.49 Geometric mean titers (GMTs) |
| QIVc (≥2 Years to <9 Years of Age) | Secondary Immunogenicity: Geometric Mean Titers for 4 Influenza Strains (HI Assay) | A/H3N2 Day 1 HI GMT | 20.85 Geometric mean titers (GMTs) |
| Comparator (≥2 Years to <9 Years of Age) | Secondary Immunogenicity: Geometric Mean Titers for 4 Influenza Strains (HI Assay) | B/Yamagata Day 22/50 HI GMT | 21.68 Geometric mean titers (GMTs) |
| Comparator (≥2 Years to <9 Years of Age) | Secondary Immunogenicity: Geometric Mean Titers for 4 Influenza Strains (HI Assay) | A/H1N1 Day 1 HI GMT | 31.76 Geometric mean titers (GMTs) |
| Comparator (≥2 Years to <9 Years of Age) | Secondary Immunogenicity: Geometric Mean Titers for 4 Influenza Strains (HI Assay) | B/Victoria Day 22/50 HI GMT | 11.94 Geometric mean titers (GMTs) |
| Comparator (≥2 Years to <9 Years of Age) | Secondary Immunogenicity: Geometric Mean Titers for 4 Influenza Strains (HI Assay) | B/Victoria Day 1 HI GMT | 9.41 Geometric mean titers (GMTs) |
| Comparator (≥2 Years to <9 Years of Age) | Secondary Immunogenicity: Geometric Mean Titers for 4 Influenza Strains (HI Assay) | A/H3N2 Day 22/50 HI GMT | 16.73 Geometric mean titers (GMTs) |
| Comparator (≥2 Years to <9 Years of Age) | Secondary Immunogenicity: Geometric Mean Titers for 4 Influenza Strains (HI Assay) | A/H3N2 Day 1 HI GMT | 20.74 Geometric mean titers (GMTs) |
| Comparator (≥2 Years to <9 Years of Age) | Secondary Immunogenicity: Geometric Mean Titers for 4 Influenza Strains (HI Assay) | B/Yamagata Day 1 HI GMT | 27.33 Geometric mean titers (GMTs) |
| Comparator (≥2 Years to <9 Years of Age) | Secondary Immunogenicity: Geometric Mean Titers for 4 Influenza Strains (HI Assay) | A/H1N1 Day 22/50 HI GMT | 48.22 Geometric mean titers (GMTs) |
Secondary
Secondary Immunogenicity: Percentage of Subjects With HI Titer ≥1:40 for All 4 Influenza Strains (HI Assay)
Immunogenicity was characterized by HI assay 3 weeks after the last vaccination in a subset of subjects 2 to \<9 years of age enrolled in Season 2 (n=432) and Season 3 (n=319) who were immunized and had immunogenicity data at the assessed timepoints (FAS Immunogenicity). Immunogenicity was assessed at baseline (Day 1; all subjects in immunogenicity subset), at Day 22 (all previously vaccinated subjects receiving a single dose of the study vaccine), and at Days 29 and 50 (all not previously vaccinated subjects receiving 2 doses) for all 4 influenza strains using the HI assay. The measures for assessing immunogenicity as determined by HI were as follows: Percentage of subjects with an HI titer ≥1:40 on Day 22 (all previously vaccinated subjects receiving a single vaccine dose) or Days 29 and 50 (all not previously vaccinated subjects receiving 2 doses) for all 4 influenza strains
Time frame: Day 1 (all subjects), Day 22 (all previously vaccinated subjects receiving a single vaccine dose) or Days 29 and 50 (all not previously vaccinatedsubjects receiving 2 doses)
Population: Dataset used: FAS Immunogenicity = all subjects in the All Enrolled Set who received at least one dose of study vaccine and provided evaluable serum samples at both baseline and after the last vaccination.
| Arm | Measure | Group | Value (NUMBER) |
|---|---|---|---|
| QIVc (≥2 Years to <18 Years of Age) | Secondary Immunogenicity: Percentage of Subjects With HI Titer ≥1:40 for All 4 Influenza Strains (HI Assay) | A/H1N1 | 88.6 Percentage of participants |
| QIVc (≥2 Years to <18 Years of Age) | Secondary Immunogenicity: Percentage of Subjects With HI Titer ≥1:40 for All 4 Influenza Strains (HI Assay) | A/H3N2 | 90.0 Percentage of participants |
| QIVc (≥2 Years to <18 Years of Age) | Secondary Immunogenicity: Percentage of Subjects With HI Titer ≥1:40 for All 4 Influenza Strains (HI Assay) | B/Yamagata | 63.8 Percentage of participants |
| QIVc (≥2 Years to <18 Years of Age) | Secondary Immunogenicity: Percentage of Subjects With HI Titer ≥1:40 for All 4 Influenza Strains (HI Assay) | B/Victoria | 54.3 Percentage of participants |
| Non-Influenza Comparator Vaccine | Secondary Immunogenicity: Percentage of Subjects With HI Titer ≥1:40 for All 4 Influenza Strains (HI Assay) | A/H1N1 | 58.6 Percentage of participants |
| Non-Influenza Comparator Vaccine | Secondary Immunogenicity: Percentage of Subjects With HI Titer ≥1:40 for All 4 Influenza Strains (HI Assay) | B/Yamagata | 21.4 Percentage of participants |
| Non-Influenza Comparator Vaccine | Secondary Immunogenicity: Percentage of Subjects With HI Titer ≥1:40 for All 4 Influenza Strains (HI Assay) | B/Victoria | 24.30 Percentage of participants |
| Non-Influenza Comparator Vaccine | Secondary Immunogenicity: Percentage of Subjects With HI Titer ≥1:40 for All 4 Influenza Strains (HI Assay) | A/H3N2 | 92.4 Percentage of participants |
| QIVc (≥2 Years to <9 Years of Age) | Secondary Immunogenicity: Percentage of Subjects With HI Titer ≥1:40 for All 4 Influenza Strains (HI Assay) | A/H3N2 | 74.0 Percentage of participants |
| QIVc (≥2 Years to <9 Years of Age) | Secondary Immunogenicity: Percentage of Subjects With HI Titer ≥1:40 for All 4 Influenza Strains (HI Assay) | A/H1N1 | 94.8 Percentage of participants |
| QIVc (≥2 Years to <9 Years of Age) | Secondary Immunogenicity: Percentage of Subjects With HI Titer ≥1:40 for All 4 Influenza Strains (HI Assay) | B/Victoria | 68.8 Percentage of participants |
| QIVc (≥2 Years to <9 Years of Age) | Secondary Immunogenicity: Percentage of Subjects With HI Titer ≥1:40 for All 4 Influenza Strains (HI Assay) | B/Yamagata | 79.2 Percentage of participants |
| Comparator (≥2 Years to <9 Years of Age) | Secondary Immunogenicity: Percentage of Subjects With HI Titer ≥1:40 for All 4 Influenza Strains (HI Assay) | A/H1N1 | 55.2 Percentage of participants |
| Comparator (≥2 Years to <9 Years of Age) | Secondary Immunogenicity: Percentage of Subjects With HI Titer ≥1:40 for All 4 Influenza Strains (HI Assay) | A/H3N2 | 24.8 Percentage of participants |
| Comparator (≥2 Years to <9 Years of Age) | Secondary Immunogenicity: Percentage of Subjects With HI Titer ≥1:40 for All 4 Influenza Strains (HI Assay) | B/Yamagata | 46.2 Percentage of participants |
| Comparator (≥2 Years to <9 Years of Age) | Secondary Immunogenicity: Percentage of Subjects With HI Titer ≥1:40 for All 4 Influenza Strains (HI Assay) | B/Victoria | 13.1 Percentage of participants |