National and regional differences in meningococcal vaccine recommendations for individuals at an increased risk of meningococcal disease.

INTRODUCTION: Invasive meningococcal disease (IMD) is a severe, life-threatening condition caused by infection with Neisseria meningitidis. Currently available vaccines offer protection against the five most common meningococcal disease-causing serogroups and include monovalent and quadrivalent conjugate vaccines (MenA, MenC, MenACWY vaccines) and outer membrane vesicle- and/or recombinant protein-based vaccines (MenB vaccines). AREAS COVERED: Country and regional immunization programs target populations susceptible to IMD and typically emphasize the highest-risk age groups (i.e., infants, adolescents/young adults, and the elderly); however, additional groups are also considered at an elevated risk and are the focus of the current review. Specific increased-risk groups include individuals with underlying immunocompromising medical conditions, university/college students, Indigenous people, laboratory workers, military personnel, men who have sex with men, and travelers to areas with hyperendemic IMD. This review compares established meningococcal vaccination recommendations for these vulnerable groups in Europe, the United States, Australia, New Zealand, Israel, Brazil, and Turkey. EXPERT OPINION: Recommendations should be standardized to cover all groups at increased risk of IMD.

Serum bactericidal activity against circulating and reference strains of meningococcal serogroup B in the United States: A review of the strain coverage of meningococcal serogroup B (MenB) vaccines in adolescents and young adults.

Invasive meningococcal disease (IMD) is rare but associated with high morbidity and mortality. In the United States, the most vulnerable age groups are infants and adolescents/young adults, and the most common type of IMD is caused by serogroup B (MenB). MenB is preventable among adolescents and young adults with the use of two licensed vaccines, MenB-FHbp (Trumenba®, bivalent rLP2086; Pfizer Inc, Collegeville, PA) and MenB-4C (Bexsero®; GSK Vaccines, Srl, Italy). Because the effectiveness of MenB vaccination is dependent on broad vaccine coverage across circulating disease-causing strains, we reviewed the available clinical and real-world evidence regarding breadth of coverage of the two licensed vaccines in adolescents and young adults in the United States. Both vaccines protect against various MenB strains. More controlled data regarding breadth of coverage across MenB strains are available for MenB-FHbp compared with MenB-4C, whereas more observational data regarding US outbreak strain susceptibility are available for MenB-4C.

Correlates of protection for meningococcal surface protein vaccines: lessons from the past.

INTRODUCTION: Recombinant surface protein meningococcal serogroup B (MenB) vaccines are available but with different antigen compositions, leading to differences between vaccines in their immunogenicity and likely breadth of coverage. The serology and breadth of coverage assessment for MenB vaccines are multifaceted areas, and a comprehensive understanding of these complexities is required to appropriately compare licensed vaccines and those under development. AREAS COVERED: In the first of two companion papers that comprehensively review the serology and breadth of coverage assessment for MenB vaccines, the history of early meningococcal vaccines is considered in this narrative review to identify transferable lessons applicable to the currently licensed MenB vaccines and those under development, as well as their serology. EXPERT OPINION: Understanding correlates of protection and the breadth of coverage assessment for meningococcal surface protein vaccines is significantly more complex than that for capsular polysaccharide vaccines. Determination and understanding of the breadth of coverage of surface protein vaccines are clinically important and unique to each vaccine formulation. It is essential to estimate the proportion of MenB cases that are preventable by a specific vaccine to assess its overall potential impact and to compare the benefits and limitations of different vaccines in preventing invasive meningococcal disease.

Translating meningococcal serogroup B vaccines for healthcare professionals.

INTRODUCTION: Vaccination is an effective strategy to combat invasive meningococcal disease (IMD). Vaccines against the major disease-causing meningococcal serogroups are available; however, development of vaccines against serogroup B faced particular challenges, including the inability to target traditional meningococcal antigens (i.e. polysaccharide capsule) and limited alternative antigens due to serogroup B strain diversity. Two different recombinant, protein-based, serogroup B (MenB) vaccines that may address these challenges are currently available. These vaccines have been extensively evaluated in pre-licensure safety and immunogenicity trials, and recently in real-world studies on effectiveness, safety, and impact on disease burden. AREAS COVERED: This review provides healthcare professionals, particularly pediatricians, an overview of currently available MenB vaccines, including development strategies and evaluation of coverage. EXPERT OPINION: Overall, recombinant MenB vaccines are valuable tools for healthcare professionals to protect patients against IMD. Their development required innovative design approaches that overcame challenging hurdles and identified novel protein antigen targets; however, important distinctions in the approaches used in their development, evaluation, and administration exist and many unanswered questions remain. Healthcare providers frequently prescribing MenB vaccines are challenged to keep abreast of these differences to ensure patient protection against this serious disease.

A review of the immunogenicity, safety and current recommendations for the meningococcal serogroup B vaccine, MenB-FHbp.

WHAT IS KNOWN AND OBJECTIVE: This review describes invasive meningococcal disease (IMD) epidemiology in the United States, provides a brief overview of available meningococcal vaccines and discusses meningococcal serogroup B (MenB) vaccine development. Particular focus is given to the recombinant protein MenB vaccine, MenB-FHbp (Trumenba® , bivalent rLP2086) in light of recent publication of phase 3 data; the other MenB vaccine (Bexsero® , MenB-4C) has been recently reviewed. Current recommendations of the US Advisory Committee on Immunization Practices (ACIP) for MenB vaccination and potential barriers to immunization are also discussed. METHODS: Using the published literature, this article reviews the development and use of MenB-FHbp to date, with a focus on the United States. RESULTS AND DISCUSSION: Despite the availability of medical treatment, IMD is associated with significant mortality and frequently occurring serious permanent sequelae in surviving individuals. Worldwide, most IMD is caused by six serogroups (A, B, C, W, X and Y). MenB is the most common disease-causing meningococcal serogroup in the United States and has caused several recent university-based IMD outbreaks. MenB vaccines, including MenB-FHbp, are available in the United States. ACIP recommends that all individuals ≥10 years of age at increased risk for meningococcal disease receive MenB vaccination; healthy individuals 16-23 years of age are recommended MenB vaccines based on individual clinical decision-making. MenB-FHbp is used on a 2-dose schedule (0, 6 months) when vaccinating healthy individuals and on a tailored 3-dose schedule (0, 1-2, 6 months) in cases of increased risk. WHAT IS NEW AND CONCLUSION: Because vaccination provides the most effective protection against IMD, pharmacists are in an excellent position to offer evidence-based vaccine information, as well as to encourage and provide meningococcal immunizations to adolescents and young adults.

Concomitant administration of meningococcal vaccines with other vaccines in adolescents and adults: a review of available evidence.

Invasive meningococcal disease (IMD), a rapidly progressing and potentially fatal illness, disproportionately affects adolescents and young adults. While IMD is best prevented by vaccination, vaccine uptake in these groups is low. An evidence-based understanding of the safety and effectiveness of concomitant vaccination of meningococcal vaccines, including the newer MenB protein vaccines and the more established MenACWY conjugate vaccines, with other vaccines recommended for adolescents and young adults may help maximize vaccination opportunities. We identified 21 studies assessing concomitant administration of meningococcal vaccines with other vaccines in adolescents and adults. Although studies varied in methodology, concomitant administration generally did not affect immunogenicity of the meningococcal or coadministered vaccines. In some cases, reactogenicity increased following concomitant administration, but no definitive safety concerns were raised. In general, data suggest that meningococcal vaccines can be safely and effectively coadministered with other vaccines.

Experience implementing a university-based mass immunization program in response to a meningococcal B outbreak.

Neisseria meningitidis serogroup B (MenB) has caused several recent outbreaks of meningococcal disease on US college campuses. In January 2015, a case of MenB was reported at a university in Oregon, culminating in an outbreak with a total of 7 cases (including 1 fatality) identified over a 5-month period. In response to the outbreak, the university organized a mass immunization campaign with 4 "opt-in" immunization clinics. The preparation, challenges, and resources required for organization and implementation of a mass immunization program in response to an outbreak at a large public university are discussed herein. Based on the logistical challenges as well as resource expenditures associated with planning and executing a mass immunization effort, this experience illustrates that proactive, routine immunization of incoming students is the best strategy for MenB outbreak prevention.

Meningococcal disease in adolescents and young adults: a review of the rationale for prevention through vaccination.

Invasive meningococcal disease (IMD) caused by Neisseria meningitidis is characterized by high mortality and morbidity. While IMD incidence peaks in both infants and adolescents/young adults, carriage rates are often highest in the latter age groups, increasing IMD risk and the likelihood of transmission. Effective vaccines are available for 5 of 6 disease-causing serogroups. Because adolescents/young adults represent a significant proportion of cases, often have the highest carriage rate, and have characteristically low vaccination adherence, efforts should be focused on educating this population regarding long-term consequences of infection and the importance of meningococcal vaccination in prevention. This review describes the role of adolescents/young adults in meningococcal transmission and the clinical consequences and characteristics of IMD in this population. With a focus on countries with advanced economies that have specific meningococcal vaccination recommendations, the epidemiology of meningococcal disease and vaccination recommendations in adolescents/young adults will also be discussed.

Impact of meningococcal vaccination on carriage and disease transmission: A review of the literature.

Colonization of the human nasopharyngeal tract by the bacterium Neisseria meningitidis is usually asymptomatic, but life-threatening meningococcal disease with a clinical presentation of meningitis, septicemia, or more rarely, gastrointestinal symptoms, can develop. Invasive meningococcal disease (IMD) can be fatal within 24 hours, but IMD is vaccine-preventable. Vaccines used to protect against IMD caused by 5 of the 6 most common serogroups (A, B, C, W, and Y) may also influence carriage prevalence in vaccinated individuals. Lower carriage among vaccinated people may reduce transmission to nonvaccinated individuals to provide herd protection against IMD. This article reviews observational and clinical studies examining effects of vaccination on N. meningitidis carriage prevalence in the context of mass vaccination campaigns and routine immunization programs. Challenges associated with carriage studies are presented alongside considerations for design of future studies to assess the impact of vaccination on carriage.