Safety and Immunogenicity of Three Influenza Vaccines in Children Aged 4 Years Old to Less Than 18 Years Old

Immunogenicity of QIVc to comparator TIV1c (For A/H1N1, A/H3N2 and B1 strain, the comparison was between QIVc and TIV1c and for B2 i.e. alternate B strain, the comparison was between QIVc and TIV2c) was assessed in terms of GMT in subjects (Previously vaccinated and Not previously vaccinated) measured by hemagglutination inhibition (HI) assay, three weeks after last vaccination with one or two doses of either QIVc, TIV1c or TIV2c. Non-inferiority was established if the upper bound of the two-sided 95% confidence interval (CI) for the ratio of GMTs (GMT TIV1c or TIV2c /GMT QIVc) for HI antibody does not exceed the non-inferiority margin of 1.5.

Immunogenicity of QIVc to comparator TIVc (For A/H1N1, A/H3N2 and B1 strain, the comparison was between QIVc and TIV1c and for B2 i.e. alternate B strain, the comparison was between QIVc and TIV2c) was assessed in terms of number (%) of subjects (Previously vaccinated and Not previously vaccinated) showing seroconversion or significant increase (at least a 4-fold increase in HI titer in subjects seropositive at baseline [i.e., HI titer ≥1:10 at Day 1] ) in HI antibody titers, three weeks after last vaccination with one or two doses of either QIVc, TIV1c or TIV2c Seroconversion was defined in subjects seronegative at baseline (i.e., HI titer <1:10 at Day 1) as postvaccination HI titer ≥1:40, and defined in subjects seropositive at baseline (i.e., HI titer ≥1:10 at Day 1) as a minimum of a 4-fold increase in post-vaccination HI titer.

Immunogenicity was assessed in terms of number (%) of subjects (Previously vaccinated and Not previously vaccinated) showing seroconversion or significant increase in HI antibody titers, three weeks after last vaccination with one or two doses of either QIVc, TIV1c or TIV2c For A/H1N1, A/H3N2 and B1 strain, the comparison was between QIVc and TIV1c and for B2 i.e. alternate B strain, the comparison was between QIVc and TIV2c Seroconversion was defined in subjects seronegative at baseline (i.e., HI titer <1:10 at Day 1) as postvaccination HI titer ≥1:40, and defined in subjects seropositive at baseline (i.e., HI titer ≥1:10 at Day 1) as a minimum of a 4-fold increase in post-vaccination HI titer. The Center for Biologics Evaluation, Research, and Review (CBER) criterion for an adult population is that the lower bound of the two-sided 95% CI for the percentage of subjects achieving seroconversion for HI antibody should meet or exceed 40%

Immunogenicity was assessed in terms of number (%) of subjects (Previously vaccinated and Not previously vaccinated) showing HI titer ≥1:40, three weeks after last vaccination with one or two doses of either QIVc, TIV1c or TIV2c For A/H1N1, A/H3N2 and B1 strain, the comparison was between QIVc and TIV1c and for B2 i.e. alternate B strain, the comparison was between QIVc and TIV2c. The CBER criterion for adult population was that the lower bound of the two-sided 95% CI for the percentage of subjects achieving an HI antibody titer ≥1:40 should meet or exceed 70%

Immunogenicity was assessed in terms of number (%) of subjects (Previously vaccinated and Not previously vaccinated) showing seroconversion or significant increase in HI antibody titers, three weeks after last vaccination with one or two doses of either QIVc, TIV1c or TIV2c For A/H1N1, A/H3N2 and B1 strain, the comparison was between QIVc and TIV1c and for B2 i.e. alternate B strain, the comparison was between QIVc and TIV2c Seroconversion was defined in subjects seronegative at baseline (i.e., HI titer <1:10 at Day 1) as postvaccination HI titer ≥1:40, and defined in subjects seropositive at baseline (i.e., HI titer ≥1:10 at Day 1) as a minimum of a 4-fold increase in post-vaccination HI titer.

Immunogenicity was assessed in terms of number (%) of subjects (Previously vaccinated and Not previously vaccinated) showing HI titer ≥1:40, three weeks after last vaccination with one or two doses of either QIVc, TIV1c or TIV2c For A/H1N1, A/H3N2 and B1 strain, the comparison was between QIVc and TIV1c and for B2 i.e. alternate B strain, the comparison was between QIVc and TIV2c The Committee for Medicinal Products for Human Use (CHMP) criterion for an adult population was that the percentage of subjects achieving an HI titer ≥1:40 is >70%

Immunogenicity was measured in subjects (Previously vaccinated and Not previously vaccinated) as the geometric mean ratio (GMR). The ratio of postvaccination to prevaccination HI GMTs, three weeks after last vaccination with one or two doses of either QIVc, TIV1c or TIV2c .For A/H1N1, A/H3N2 and B1 strain, the comparison was between QIVc and TIV1c and for B2 i.e. alternate B strain, the comparison was between QIVc and TIV2c The CHMP criterion for GMR in adult population is >2.5

Immunogenicity of QIVc to comparator TIV1c was assessed in terms of GMT in subjects (Previously vaccinated and Not previously vaccinated) measured by HI assay, three weeks after last vaccination with one or two doses of either QIVc or TIV1c. Superiority was established if the upper bound of the two-sided 95% CI for the ratio of GMTs (GMT TIV1c /GMT QIVc) for HI antibody did not exceed the superiority margin of 1

Immunogenicity of QIVc to comparator TIV1c in terms of number (%) of subjects (Previously vaccinated and Not previously vaccinated) showing seroconversion or significant increase in HI antibody titers, against influenza strain B2, three weeks after last vaccination with QIVc or TIV1c. Superiority criterion was established if the upper bound of the two-sided 95% CI for the difference between seroconversion rates (% seroconversion TIV1c - % seroconversion QIVc) for HI antibody does not exceed the margin of 0 points

Immunogenicity of QIVc to comparator TIV2c was assessed in terms of GMT in subjects (Previously vaccinated and Not previously vaccinated) measured by HI assay, three weeks after last vaccination with one or two doses of either QIVc or TIV2c. Superiority was established if the upper bound of the two-sided 95% CI for the ratio of GMTs (GMT TIV2c /GMT QIVc) for HI antibody does not exceed the superiority margin of 1

Immunogenicity of QIVc to comparator TIV2c in terms of number (%) of subjects (Previously vaccinated and Not previously vaccinated) showing seroconversion or significant increase in HI antibody titers, against influenza strain B1, three weeks after last vaccination with QIVc or TIV2c. Superiority was established if the upper bound of the two-sided 95% CI for the difference between seroconversion rates (% seroconversion TIV2c - % seroconversion QIVc) for HI antibody does not exceed the margin of 0 points

Safety was assessed in terms of number of subjects (Previously vaccinated and Not previously vaccinated) reporting solicited local and systemic reactions, day 1 to 7 after last vaccination with one or two doses of either QIVc, TIV1c or TIV2c.For A/H1N1, A/H3N2 and B1 strain, the comparison was between QIVc and TIV1c and for B2 i.e. alternate B strain, the comparison is between QIVc and TIV2c.

Safety was assessed in terms of number of subjects (Previously vaccinated and Not previously vaccinated) reporting unsolicited AEs (day 1 to 22 for Previously vaccinated and day 1 to day 50 for Not previously vaccinated subjects), serious adverse events (SAEs), medically attended AEs, AEs leading to withdrawal from the study, new onset of chronic diseases (NOCDs), and concomitant medications (day 1 to day 181 for Previously vaccinated and day 1 to day 210 for Not previously vaccinated subjects) after receiving one or two doses of either QIVc, TIV1c or TIV2c. For A/H1N1, A/H3N2 and B1 strain, the comparison is between QIVc and TIV1c and for B2 i.e. alternate B strain, the comparison was between QIVc and TIV2c.