Epidemiologic Trends, Global Shifts in Meningococcal Vaccination Guidelines, and Data Supporting the Use of MenACWY-TT Vaccine: A Review

Abstract

Neisseria meningitidis is a major cause of meningitis and septicemia with cases, outbreaks, and epidemics reported globally in industrialized and non-industrialized countries. N. meningitidis is categorized into 12 serogroups; however, only 5 serogroups (A, B, C, W, Y) are responsible for the majority of disease. Invasive meningococcal disease (IMD) occurs unpredictably; protection is therefore best achieved by initiating proactive vaccination strategies. Vaccines are currently available for the five main disease-causing serogroups. With the evolution of meningococcal vaccines and changes in IMD epidemiology, different vaccination strategies have been used. Recently, the rapid clonal expansion of meningococcal serogroup W (MenW) has been associated with a change in the national and regional vaccination recommendations from monovalent meningococcal serogroup C vaccines to meningococcal serogroup A, C, W, Y (MenACWY) vaccines in several countries. This review highlights these and other changes in IMD epidemiology and meningococcal vaccination recommendations, summarizes information available for currently available conjugate MenACWY vaccines, and focuses on clinical study data for the most recently approved MenACWY conjugate vaccine, MenACWY vaccine conjugated to tetanus toxoid (MenACWY-TT). MenACWY-TT studies spanned multiple age groups and generally demonstrated safety and immunogenicity in comparison with other meningococcal vaccines and under concomitant administration of other routine vaccines. Continuous updates to meningococcal vaccine recommendations in response to changing epidemiology, as have been undertaken for MenW, are necessary to ensure optimal population protection. Funding Pfizer, Inc.

Vaccines against Meningococcal Diseases

“…It has been licensed since 2005 in the USA and is currently approved for infants 9–23 months old as two doses and for individuals from 2 to 55 years old as a single dose [ 49 ]. Currently it is not approved in Europe [ 50 ]. It can be co-administered with other vaccines, but the immunogenicity of some co-administered vaccines is affected [ 49 ].…”

“…MenACWY-TT ( Nimenrix , Pfizer) was approved in 2012, in Europe, in infants aged six weeks or greater with no upper age limit [ 50 ]. It is indicated for use as a two-dose series in healthy infants from six weeks to less than six months of age followed by a booster dose at 12 months of age, and as a single dose from six months of age [ 65 ].…”

“…It is indicated for use as a two-dose series in healthy infants from six weeks to less than six months of age followed by a booster dose at 12 months of age, and as a single dose from six months of age [ 65 ]. It is currently not approved for use in the USA [ 50 ].…”

“…The immunogenicity, persistence, and safety profile of MenACWY-TT have been established in multiple clinical studies across various age groups (infants, toddlers, children, adolescents, and young adults) while co-administered with routine vaccines [ 50 ]. A booster dose in persons previously vaccinated with a conjugate or polysaccharide meningococcal vaccine has also been shown to be immunogenic and safe [ 66 ].…”

Invasive Meningococcal Disease in Italy: from the analysis of national data to an evidence-based vaccination strategy.

“…In particular, an increase in cases of IMD related to serogroups Y and W was described [ 40 , 41 , 48 ], whereas serogroup C was almost s from 2012 to 2014, increasing in 2015 and 2016 [ 40 , 43-45 ]. This epidemiological evidence, as well as the possibility of capsular switch from one serogroup to another [ 12 , 18-22 ], should lead the national decision makers to boost the use of the MenACWY vaccine instead of MenC in the next PNPV, as already done in Emilia-Romagna [ 49 ], Apulia [ 50 ] and Sicily [ 51 , 52 ] and recently implemented in other countries [ 53 , 54 ], to ensure more comprehensive protection.…”