Persistence of bactericidal antibodies to 5 years of age after immunization with serogroup B meningococcal vaccines at 6, 8, 12 and 40 months of age.

BACKGROUND: A serogroup B meningococcal vaccine (4CMenB) has been licensed by the European commission for use in various infant schedules. However, data are limited on persistence of serum bactericidal antibodies (SBA), which is necessary to inform cost-effectiveness analysis. METHODS: Sera were obtained from 3 groups of 5-year-old children previously immunized at 6, 8, 12 and 40 months with either 4CMenB or rMenB (which lacks the outer membrane vesicle of 4CMenB) or at 40 and 42 months with 4CMenB only. Forty-nine control children were also recruited and blood obtained before and after 2 doses of 4CMenB at 60 and 62 months of age. Sera were tested for SBA to meningococcal B reference strains. RESULTS: At 5 years of age, 67% of those receiving 4CMenB in infancy had SBA titers ≥1:4 for strain 44/76, 100% for 5/99, 17% for NZ98/254 and 45% for M10713. Results for rMenB recipients varied from 0 (NZ98/254) to 100% (5/99). Of those immunized with 4CMenB at 40 and 42 months, 38% had SBA titers ≥1:4 at age 5 for 44/76, 100% for 5/99, 0% (NZ98/254) and 83% (M10713). Among controls, SBA titers were ≥1:4 in 4% (H44/76, 5/99), 0% (NZ98/254) and 67% (M10713) at baseline, increasing to 100% (H44/76 and 5/99), 89% (NZ98/254) and 97% (M10713) postimmunization. CONCLUSION: The variable rates of waning of antibody to the 4 components of 4CMenB complicates estimates of duration of protection and should be taken into account in cost-effectiveness analyses. A 2-dose schedule of 4CMenB in 5-year-old children was immunogenic

Persistence of bactericidal antibodies to 5 years of age after immunization with serogroup B meningococcal vaccines at 6, 8, 12 and 40 months of age.

BACKGROUND: A serogroup B meningococcal vaccine (4CMenB) has been licensed by the European commission for use in various infant schedules. However, data are limited on persistence of serum bactericidal antibodies (SBA), which is necessary to inform cost-effectiveness analysis. METHODS: Sera were obtained from 3 groups of 5-year-old children previously immunized at 6, 8, 12 and 40 months with either 4CMenB or rMenB (which lacks the outer membrane vesicle of 4CMenB) or at 40 and 42 months with 4CMenB only. Forty-nine control children were also recruited and blood obtained before and after 2 doses of 4CMenB at 60 and 62 months of age. Sera were tested for SBA to meningococcal B reference strains. RESULTS: At 5 years of age, 67% of those receiving 4CMenB in infancy had SBA titers ≥1:4 for strain 44/76, 100% for 5/99, 17% for NZ98/254 and 45% for M10713. Results for rMenB recipients varied from 0 (NZ98/254) to 100% (5/99). Of those immunized with 4CMenB at 40 and 42 months, 38% had SBA titers ≥1:4 at age 5 for 44/76, 100% for 5/99, 0% (NZ98/254) and 83% (M10713). Among controls, SBA titers were ≥1:4 in 4% (H44/76, 5/99), 0% (NZ98/254) and 67% (M10713) at baseline, increasing to 100% (H44/76 and 5/99), 89% (NZ98/254) and 97% (M10713) postimmunization. CONCLUSION: The variable rates of waning of antibody to the 4 components of 4CMenB complicates estimates of duration of protection and should be taken into account in cost-effectiveness analyses. A 2-dose schedule of 4CMenB in 5-year-old children was immunogenic

Persistence of bactericidal antibodies following early infant vaccination with a serogroup B meningococcal vaccine and immunogenicity of a preschool booster dose

Background: The multicomponent serogroup B meningococcal (4CMenB) vaccine was recently licensed for use in Europe. There are currently no data on the persistence of bactericidal antibodies induced by use of this vaccine in infants. Our objective was to evaluate serogroup B–specific bactericidal antibodies in children aged 40–44 months previously vaccinated at 2, 4, 6 and 12 months of age. Methods: Participants given 4 doses of 4CMenB as infants received a fifth dose of the vaccine at 40–44 months of age. Age-matched participants who were MenB vaccine–naive received 4CMenB and formed the control group. We evaluated human complement serum bactericidal activity (hSBA) titres at baseline and 1 month after each dose of 4CMenB. Results: Before a booster dose at enrolment, 41%–76% of 17 participants previously vaccinated with 4CMenB in infancy had hSBA titres of 4 or greater against 4 reference strains. Before vaccination in the control group (n = 40) these proportions were similar for strains 44/76-SL (63%) and M10713 (68%) but low for strains NZ98/254 (0%) and 5/99 (3%). A booster dose in the 4CMenB-primed participants generated greater increases in hSBA titres than in controls. Interpretation: As has been observed with other meningococcal vaccines, bactericidal antibodies waned after vaccination with 4CMenB administered according to an approved infant vaccination schedule of 2, 4, 6 and 12 months of age, but there was an anamnestic response to a booster dose at 40–44 months of age. If 4CMenB were introduced into routine vaccination schedules, assessment of the need for a booster dose would require data on the impact of these declining titres on vaccine effectiveness. ClinicalTrials.gov, no. NCT01027351</p

Bactericidal antibody persistence 2 years after immunization with 2 investigational serogroup B meningococcal vaccines at 6, 8 and 12 months and immunogenicity of preschool booster doses: A follow-on study to a randomized clinical trial

Background: In a previous study, 60 infants receiving an investigational serogroup B meningococcal vaccine containing recombinant meningococcal proteins alone (rMenB) or combined with an outer membrane vesicle from Neisseria meningitidis (4CMenB) at 6, 8 and 12 months of age produced serum bactericidal antibodies (SBAs) against meningococcal strains expressing vaccine antigens. We studied persistence of this response and the response to a booster dose of vaccine. Methods: In this extension study, SBA titers were evaluated before and after a booster dose of rMenB or 4CMenB at 40 months of age. MenB vaccine naïve age-matched children served as a control group. Results: Before the booster doses, the proportions of 4CMenB recipients with SBA titers ≥1:4 were 36% (n = 14, 95% confidence interval: 13-65%) for strain 44/76-SL, 100% (77-100%) for 5/99, 14% (2-43%) for NZ98/254 and 79% (49-95%) for M10713. These percentages were 14% to 29% for rMenB recipients (n = 14), except for 5/99 (93%, 66-100%). For controls (n = 40), these proportions were ≤3% for all strains except M10713 (53%, 36-68%). One month after the boosters, ≥93% of 4CMenB recipients had SBA titers ≥1:4 for all 4 strains. For controls receiving their first dose of 4CMenB, 23% (11-39%) had SBA titers ≥1:4 for NZ98/254, compared with 62% to 87% for the remaining strains. Conclusions: Bactericidal antibodies wane after infant immunization with rMenB or 4CMenB, but there is an anamnestic response to a booster dose. Booster doses of 4CMenB may be required to maintain immune protection through childhood and adolescence. Copyright © 2013 by Lippincott Williams and Wilkins

Immunogenicity and immune memory of a nonadjuvanted quadrivalent meningococcal glycoconjugate vaccine in infants.

BACKGROUND: The highest rate of invasive meningococcal disease is among children under 2 years of age. There is currently no licensed quadrivalent (serogroups A, C, W-135, and Y) meningococcal glycoconjugate vaccine approved for infants. We evaluated the immunogenicity and reactogenicity of a novel quadrivalent nonadjuvanted meningococcal glycoconjugate vaccine (MenACWY-CRM) in healthy infants. METHODS: One hundred eighty infants (90 in Canada and 90 in the United Kingdom) received 2 doses of MenACWY-CRM at 2 and 4 months of age administered concomitantly with routine infant vaccines. At 12 months of age, the Canadian infants received either MenACWY-CRM or a reduced dose of a licensed meningococcal polysaccharide vaccine. In the United Kingdom, all infants received a further dose of MenACWY-CRM. The serological marker of protection was a titer of > or =1:4 using a serum bactericidal assay with human complement (hSBA). RESULTS: Two doses of MenACWY-CRM induced hSBA titers > or =1:4 in 57% (95% confidence interval [CI]: 45-67) and 50% (95% CI: 38-62) of infants against serogroup A in Canada and the United Kingdom, respectively, 93% (95% CI: 85-97) and 86% (95% CI: 46-93) against serogroup C, 95% (95% CI: 87-99) and 82% (95% CI: 71-90) against serogroup W-135, and 91% (95% CI: 82-96) and 74% (95% CI: 63-83) against serogroup Y. After a booster dose of MenACWY-CRM at 12 months, at least 94% of participants achieved hSBA titers > or =1:4 against each of the serogroups C, W-135, and Y and more than 79% against serogroup A. The vaccine was well tolerated. CONCLUSIONS: The nonadjuvanted MenACWY-CRM is immunogenic and well tolerated in infancy and could provide broad protection against meningococcal disease in this vulnerable age group

Immunogenicity of a tetravalent meningococcal glycoconjugate vaccine in infants: a randomized controlled trial.

CONTEXT: Immunization with a meningococcal tetravalent (serogroup ACWY) glycoconjugate vaccine is recommended for all US adolescents. However, the currently licensed vaccine is poorly immunogenic in infancy, when the highest rates of disease are observed. OBJECTIVE: To determine the immunogenicity of a novel tetravalent CRM(197)-conjugated meningococcal vaccine (MenACWY) in infants. DESIGN, SETTING, AND PARTICIPANTS: Randomized, open-label, controlled study of 225 UK and 196 Canadian 2-month-olds from August 2004 to September 2006. INTERVENTION: UK infants received a primary course of MenACWY (at 2, 3, and 4 months or 2 and 4 months) or Neisseria meningitidis serogroup C monovalent meningococcal glycoconjugate vaccine (MenC) (at 2 and 4 months). All received MenACWY at 12 months. Canadian infants received MenACWY at 2, 4, and 6 months or 2 and 4 months; at 12 months they received MenACWY, a plain tetravalent polysaccharide vaccine, or no vaccine. MAIN OUTCOME MEASURE: Percentage of infants with a human complement serum bactericidal activity (hSBA) titer >or=1:4 after a primary course of MenACWY and after a 12-month booster. Safety and reactogenicity of MenACWY were also assessed. RESULTS: According to the prespecified per-protocol analysis, the percentages (95% CIs) of MenACWY 2-, 3-, and 4-month recipients with hSBA titers >or=1:4 after primary immunization were serogroup A, 93% (84%-98%); C, 96% (89%-99%); W-135, 97% (90%-100%); and Y, 94% (86%-98%). With a post hoc intention-to-treat analysis with imputed values for missing data, these values were unchanged for serogroups C and Y; for serogroup A, values were 92% (84%-97%), and for W-135, 97% (91%-99%). For the per-protocol analysis of MenACWY 2-, 4-, and 6-month recipients, the percentages (95% CIs) of responders were A, 81% (71%-89%); C, 98% (92%-100%); W-135, 99% (93%-100%); and Y, 98% (92%-100%). With the imputed value analysis, these values were A, 83% (74%-89%); C, 98% (93%-99%); W-135, 99% (94%-100%); and Y, 98% (92%-99%). At least 84% of MenACWY 2- and 4-month recipients achieved hSBA titers >or=1:4 for serogroups C, W-135, and Y after primary immunization, as did at least 60% for serogroup A (per-protocol and imputation analysis). At least 95% of primary and booster MenACWY recipients achieved hSBA titers >or=1:4 for serogroups C, W-135, and Y at 13 months, as did at least 84% for serogroup A (per-protocol and imputation analysis). During the primary immunization course, postimmunization pain on leg movement was observed in 2% of UK MenACWY 2- and 4-month recipients and 4% of MenC 2- and 4-month recipients; a temperature of 38 degrees C or greater was observed in 4% and 2% in these groups, respectively. CONCLUSION: MenACWY is well tolerated and immunogenic in infancy. Trial Registration clinicaltrials.gov Identifier: NCT00262002