Immunogenicity of MenACWY-CRM was considered noninferior to MCV4 for any of the four groups if the lower limit of the two-sided 95% confidence interval SB431542 in vivo around the difference of the percentage of participants with a seroresponse (or hSBA ≥8) for that group (MenACWY-CRM minus MCV4) was greater than −10%. A MenACWY-CRM group

was considered to have a statistically superior immune response compared to MCV4 if the lower limit of the two-sided 95% confidence interval around the difference in percentage of participants was greater than 0 (i.e., the CI did not include 0). Geometric mean titers (GMTs) and two-sided 95% CIs were calculated for each vaccine group and for each EGFR inhibitor drugs group pre- and postvaccination by exponentiating (base 10) the least-squares

means of the logarithmically transformed (base 10) titers and their 95% CIs obtained from a two-way Analysis of Variance (ANOVA) with factors for vaccine group and center. Titers below the detection limit were set to half that limit for the purpose of analysis. As an additional secondary objective analysis, the immunogenicity of the combined group of children aged 2–10 years was analyzed. A sample size of 680 per group in the 2–5-year-olds and 560 per group for the 6–10-year-olds was estimated to provide 95–99% power to demonstrate noninferiority for each of the four groups, 88% power within for each age group to demonstrate noninferiority for all four groups and 77% power to show noninferiority of all four groups across both age strata (2–10 years of age). Inclusion of 325 participants who received the two-dose MenACWY-CRM regimen was calculated to provide 84–94% power to demonstrate superiority of the two-dose regimen in children 2–5 years of age at alpha of 0.05. A total

of 2907 children between 2 and 10 years of age were enrolled in the study. There were 1751 children 2–5 years of age randomly allocated 1:2:2 to receive two doses of MenACWY-CRM (n = 359), one dose of MCV4 (n = 696), or one dose of MenACWY-CRM (n = 696). There were 1156 children 6–10 years of age randomly allocated 1:1 to receive MCV4 (n = 574) or MenACWY-CRM (n = 582). The male/female distribution, race, and weight and height were similar within each age stratum ( Table 2). In total, 2802 (96.4%) participants completed the protocol (Fig. 1). There were 105 premature withdrawals (26 in the two-dose MenACWY-CRM group, 27 in the single-dose MenACWY-CRM 2–5-year-old group, 24 in the single-dose MCV4 2–5-year-old group, 11 in the single-dose MenACWY-CRM 6–10-year-old group and 17 in the single-dose MCV4 6–10-year-old group).