Perspective

Booster dose of 4CMenB increased protection

A booster dose of a new vaccine that protects against meningitis B bacteria can overcome waning immunity induced by infant vaccination, according to recent study results published in CMAJ.

Healthy children who received four doses of serogroup B meningococcal vaccine (4CMenB, Novartis) and a fifth dose of the vaccine at aged 40 to 44 months constituted the intervention group. The control group consisted of age-matched vaccine-naive participants who received 4CMenB.

Before enrollment, 41% to 76% of the intervention group had human complement serum bactericidal activity (hSBA) titers of four or more against four reference strains. Before vaccination, these rates in the control group were similar for 44/76-SL (63%) and M10713 (68%) but low for strains NZ98/254 (0%) and 5/99 (3%). The intervention group had greater increases in hSBA titers than controls after the booster dose.

“Consistent with other vaccines against meningococcal disease, a waning of hSBA titers was observed after infant vaccination with 4CMenB,” the researchers wrote. “A booster dose during preschool years was well tolerated. If 4CMenB were to be introduced into a routine vaccination schedule, measures such as adequate disease surveillance would be important to determine whether waning of antibodies might influence the effectiveness of a vaccination campaign against this bacterium.”

Disclosure: See the study for a full list of disclosures.

A booster dose of a new vaccine that protects against meningitis B bacteria can overcome waning immunity induced by infant vaccination, according to recent study results published in CMAJ.

Healthy children who received four doses of serogroup B meningococcal vaccine (4CMenB, Novartis) and a fifth dose of the vaccine at aged 40 to 44 months constituted the intervention group. The control group consisted of age-matched vaccine-naive participants who received 4CMenB.

Before enrollment, 41% to 76% of the intervention group had human complement serum bactericidal activity (hSBA) titers of four or more against four reference strains. Before vaccination, these rates in the control group were similar for 44/76-SL (63%) and M10713 (68%) but low for strains NZ98/254 (0%) and 5/99 (3%). The intervention group had greater increases in hSBA titers than controls after the booster dose.

“Consistent with other vaccines against meningococcal disease, a waning of hSBA titers was observed after infant vaccination with 4CMenB,” the researchers wrote. “A booster dose during preschool years was well tolerated. If 4CMenB were to be introduced into a routine vaccination schedule, measures such as adequate disease surveillance would be important to determine whether waning of antibodies might influence the effectiveness of a vaccination campaign against this bacterium.”

Disclosure: See the study for a full list of disclosures.

    Perspective
    Carol J. Baker

    Carol J. Baker

    Snape and colleagues report that a fifth or booster dose of the multicomponent serogroup B meningococcal (4MenB) B vaccine given to 40- to 44-month-old children previously 4MenB immunized at 2, 4, 6 and 12 months of age resulted in a good anamnestic response compared to vaccine-naïve controls. The U.K., where this study was conducted, recently considered and rejected a recommendation for routine use of 4MenB in infants based on the limited vaccine preventable disease burden and the unfavorable cost-effectiveness.

    The study by Snape et al provides evidence that like other meningococcal vaccines, bactericidal antibodies, a correlate of protection, wane among young children 2-3 years after the primary series and first booster, but elicit a robust immune response to the second booster or fifth dose. However, hSBA activity, a correlate of protection for capsular polysaccharide-protein conjugate meningococcal vaccines, is based on antibodies binding to a single capsular epitope.

    For 4MenB vaccine, 4 distinct protein components that have considerable interstrain variation make the “protection” assumption far less certain. Furthermore, it is likely that herd immunity will be required for 4MenB to be protective in any given target population, and it is not known whether it diminishes nasopharyngeal carriage among unvaccinated in a manner similar to Haemophilus influenzae and Streptococcus pneumoniae conjugate vaccines. Until the burden of meningococcal serogroup B disease is such to justify routine use of 4MenB in infants and young children, the potential effectiveness of this vaccine will remain uncertain.

    • Carol J. Baker, MD
    • Professor, Molecular Virology & Microbiology Baylor College of Medicine

    Disclosures: Baker reported being a consultant for Novartis Vaccines and Diagnostic.