Evaluation of Meningococcal Immune Response Among Children Who Previously Received MenACWY Conjugate Vaccine

The persistence of the antibody response in subjects of 60 months of age previously vaccinated with MenACWY-CRM in the parent study, and baseline antibody levels in age-matched naive subjects, is measured by the percentages of subjects with human Serum Bactericidal Assay (hSBA) titers ≥ 1:8 directed against N. meningitidis serogroups A, C, W-135, and Y.

Time frame: Visit 10, 60 months of age

Population: Analysis was done on the Per Protocol Set 60-Month persistence (PPS 60-Month persistence), ie, all subjects in the enrolled population who provided an evaluable serum sample at the 60-month of age visit and had no major protocol deviation.

The persistence of the antibody response in subjects of 40 months of age, previously vaccinated with MenACWY-CRM in the parent study, and baseline antibody levels in age-matched naive subjects, is measured by the percentage of subjects with human Serum Bactericidal Assay (hSBA) titers ≥ 1:8 directed against N. meningitidis serogroups A, C, W-135, and Y.

Time frame: Visit 9 (continuation from the parent study), 40-month visit.

Population: Analysis was done on the Per Protocol Set 40-month persistence (PPS 40-month persistence), ie, all subjects in the enrolled population who provided an evaluable serum sample at the 40-months of age visit and had no major protocol deviation.

The persistence of the antibody response in children of 40 months of age previously vaccinated with MenACWY-CRM in study V59P14 (NCT00474526), and baseline antibody levels in age-matched naive subjects, is measured by the hSBA GMTs directed against N meningitidis serogroups A, C, W-135, and Y.

Time frame: Visit 9 (continuation from the parent study), 40-months of age.

Population: Analysis was done on the PPS 40-month persistence.

The persistence of the antibody response in children of 60 months of age previously vaccinated with MenACWY-CRM in study V59P14 (NCT00474526), and baseline antibody levels in age-matched naive subjects is measured by the hSBA GMTs directed against N meningitidis serogroups A, C, W-135, and Y.

Time frame: Visit 10, 60 months of age.

Population: Analysis was done on the PPS 60-Month persistence.

Number of subjects reporting solicited local and systemic Adverse Events (AEs) and other indicators of reactogenicity after receiving study vaccination. Note: solicited AEs were not recorded for naive subjects at 40 months of age, but only SAEs and medically attended AEs.

Time frame: From day 1 to 7 after vaccination.

Population: Analysis was done on the Solicited Safety Set (from 6 hours to day 7), ie, all subjects who received a vaccination at 60 months and provided postvaccination solicited safety data.

Number of subjects reporting unsolicited AEs, serious adverse events (SAEs) and medically attended AEs after receiving study vaccination.

Time frame: Day 1 to 7 after vaccination for any unsolicited AEs, day 1 to study termination for SAEs and medically attended AEs (for the naive-40 group), day 8 to study termination for SAEs and medically attended AEs (for the other groups).

Population: Analysis was done on the Post MenACWY at 60 months safety set ie, all subjects who received a vaccination at 60 months and were assessed for postvaccination safety, and on the Post MenACWY at 40 Months Safety Set, ie, the Naive subjects enrolled at 40 months of age who received vaccination at 40 months and were assessed for post vaccination safety.

The antibody response to one booster dose of MenACWY-CRM in children of 60 months of age who had previously received at least one dose of MenACWY-CRM in the parent study, compared to the antibody response to one dose of MenACWY-CRM in meningococcal vaccine-naïve subjects, is measured by the percentage of subjects with seroresponse at 1 month post-vaccination. Seroresponse is defined as hSBA ≥ 1:8 for subjects with pre-vaccination hSBA titer ≤1:4, and as at least a four-fold rise in hSBA for subjects with pre-vaccination hSBA titer ≥ 1:4.

Time frame: Visit 11, 1 month after vaccination.

Population: Analysis was done on the PPS Post-MenACWY-CRM.

The persistence of the antibody response in subjects of 40 months of age previously vaccinated with MenACWY-CRM in the parent study, and baseline antibody levels in age-matched naive subjects, is measured by the percentage of subjects with human Serum Bactericidal Assay (hSBA) titers ≥ 1:4 directed against N. meningitidis serogroups A, C, W-135, and Y.

Time frame: Visit 9, 40 months of age.

Population: Analysis was done on the PPS 40-month persistence.

The persistence of the antibody response in subjects of 60 months of age previously vaccinated with MenACWY-CRM in the parent study, and baseline antibody levels in age-matched naive subjects, is measured by the percentage of subjects with human Serum Bactericidal Assay (hSBA) titers ≥ 1:4 directed against N. meningitidis serogroups A, C, W-135, and Y.

Time frame: Visit 10, 60 months of age.

Population: Analysis was done on the PPS 60-Month persistence.

The antibody response to one booster dose of MenACWY-CRM in children of 60 months of age who had previously received at least one dose of MenACWY-CRM in the parent study compared to the antibody response to one dose of MenACWY-CRM in meningococcal vaccine-naïve subjects, is measured by the percentage of subjects with hSBA titers ≥ 1:8 and ≥1:4 directed against N. meningitidis serogroups A, C, W-135, and Y, at 1 month post-vaccination.

Time frame: Visit 11, 1 month after vaccination.

Population: Analysis was done on the PPS-Immunogenicity after one dose of MenACWY-CRM (PPS Post-MenACWY-CRM), ie, all subjects in the enrolled population who correctly received the vaccine, provided at least one evaluable serum sample at the relevant time points and whose assay result was available for at least one serogroup with no major protocol deviation.