Routine vaccination against MenB: considerations for implementation

Health Technology Assessment for Vaccines Against Rare, Severe Infections: Properly Accounting for Serogroup B Meningococcal Vaccination's Full Social and Economic Benefits

The high price of new generations of vaccines relative to their predecessors has become an important consideration in debates over whether the benefits of the new vaccines justify their costs. An increasingly central line of inquiry in the literature on valuing vaccination surrounds accounting for the full social and economic benefits of vaccination. This paper applies this emerging perspective to the particular case of vaccination against serogroup B meningococcal disease (MenB). We explore key issues involved in health technology assessments of MenB vaccination, which have led to pronounced heterogeneity in evaluation methods and recommendation outcomes across countries such as France, Germany, the US, and the UK. Accounting for typically neglected sources of socioeconomic benefit could potentially impact recommendation and reimbursement decisions. We propose a taxonomy of such benefits built around four dimensions: (i) internalized health benefits, (ii) internalized non-health benefits, (iii) externalized health benefits, and (iv) externalized non-health benefits. This approach offers a systematic, comprehensive evaluation framework that can be used in future assessment of MenB vaccines as well as other health technologies.

Cost-effectiveness of alternative strategies for vaccination of adolescents against serogroup B IMD with the MenB-FHbp vaccine in Canada

OBJECTIVE

Serogroup B meningococci (MnB) are now the largest cause of invasive meningococcal disease (IMD) in Canada. We assessed the clinical and economic impact of 3 adolescent MenB-FHbp immunization strategies.

METHODS

A population-based dynamic transmission model was developed to simulate the transmission of MnB among the entire Canadian population over a 30-year time horizon. Age group-based IMD incidence, bacterial carriage and transmission, disease outcomes, costs, and impact on quality of life were obtained from Canadian surveillance data and published literature. The vaccine was assumed to provide 85% protection against IMD and 26.6% against carriage acquisition. The model estimated the impact of routine vaccination with MenB-FHbp in 3 strategies: (1) age 14, along with existing school-based programs, with 75% uptake; (2) age 17 with 75% uptake, assuming school vaccination; and (3) age 17 with 30% uptake, assuming vaccination outside of school. Costs were calculated from the Canadian societal perspective.

RESULTS

With no vaccination, an estimated 3974 MnB cases would be expected over 30 years. Vaccination with strategies 1-3 were estimated to avert 688, 1033, and 575 cases, respectively. These outcomes were associated with incremental costs per quality-adjusted life-year of $976,000, $685,000, and $490,000.

CONCLUSIONS

Our model indicated that if the vaccine reduces risk of carriage acquisition, vaccination of older adolescents, even at lower uptake, could have a significant public health impact. Due to low disease incidence, MnB vaccination is unlikely to meet widely accepted cost-effectiveness thresholds, but evaluations of new programs should consider the overall benefits of the vaccination.

Global epidemiology of serogroup B meningococcal disease and opportunities for prevention with novel recombinant protein vaccines

BACKGROUND

Meningococcal disease (MD) is a major cause of meningitis and sepsis worldwide, with a high case fatality rate and frequent sequelae. Neisseria meningitidis serogroups A, B, C, W, X and Y are responsible for most of these life-threatening infections, and its unpredictable epidemiology can cause outbreaks in communities, with significant health, social and economic impact. Currently, serogroup B is the main cause of MD in Europe and North America and one of the most prevalent serogroups in Latin America. Mass vaccination strategies using polysaccharide vaccines have been deployed since the 1970s and the use of conjugate vaccines has controlled endemic and epidemic disease caused by serogroups A, C, W and Y and more recently serogroup B using geographically-specific outer membrane vesicle based vaccines. Two novel protein-based vaccines are a significant addition to our armamentarium against N. meningitidis as they provide broad coverage against highly diverse strains in serogroup B and other groups. Early safety, effectiveness and impact data of these vaccines are encouraging. These novel serogroup B vaccines should be actively considered for individuals at increased risk of disease and to control serogroup B outbreaks occurring in institutions or specific regions, as they are likely to save lives and prevent severe sequelae. Incorporation into national programs will require thorough country-specific analysis.

Meningococcal B vaccination: real-world experience and future perspectives

Invasive meningococcal disease (IMD) represents a severe risk for health. It can be considered the most dangerous vaccine-preventable disease due to the high probability of related permanent sequelae and death. The introduction in many countries of the conjugate vaccines against A, C, W135, and Y meningococcal serogroups influenced significantly the impact of the disease. Recently, the difficulties in obtaining an effective vaccine against meningococcal serogroup B (MenB) have been get over through the reverse vaccinology, enabling the recognition of some antigens providing a response against most of circulating MenB strains worldwide. The new 4cMenB vaccine is recommended in Europe, Canada, Australia, the USA, and some Latin American countries. Even if sound data on efficacy and safety profile are available, the results in terms of effectiveness are still limited. The management of the MenB outbreaks in two US universities demonstrated the ability to quickly achieve high vaccination coverage rates and no new cases among immunized subjects were assessed. It is desirable that the opportunity to complete preventive intervention against IMD offered by the new 4cMenB vaccine should be recognized and that this vaccine is included in the vaccination schedule to complete the panel of immunization against Neisseria meningitidis.

Over-expression of fHbp in Arabdopsis for development of meningococcal serogroup B subunit vaccine

Due to lack of commercial vaccine against the serogroup B (MenB) of Neisseria meningitides, the incidence of meningococcal disease remains high. To solve the issue, transgenic plants are used as bioreactors to produce a plant-derived fHbp subunit vaccine. In this study, the fHbp gene was optimized according to the codon usage bias of Arabidopsis thaliana, synthesized artificially, cloned into an expression vector, driven by a seed-specific promoter, and introduced into A. thaliana by Agrobacterium-mediated floral-dip transformation. Transgenic plants were identified by glufosinate selection, quickstix strips for PAT/bar tests and PCR analysis. The five plants showing higher expression of recombinant fHbp were screened through indirect ELISA. Southern blot analysis showed that the transgenic line rHF-22 had a single-copy integration and the highest expression of fHbp. Recombinant fHbp was purified from seeds of rHF-22 by nitrilotriacetic acid-mediated affinity chromatography, and the purity was 82.5%. BALB/c mice were tested for fHbp vaccine protection from lethal MenB infection, and the relative percent survival was found to be 80%. This study indicates that the recombinant fHbp produced from seeds of rHF-22 is a potential candidate for commercial MenB vaccine. It also provides a reference for safe, cheap and large-scale production of other plant-made vaccines.

New South Wales annual vaccine-preventable disease report, 2013

AIM

To describe the epidemiology of selected vaccine-preventable diseases in New South Wales, Australia for 2013.

METHODS

Data from the New South Wales Notifiable Conditions Information Management System were analysed by local health district of residence, age, Aboriginality, vaccination status and organism. Risk factor and vaccination status data were collected by public health units.

RESULTS

Pertussis notification rates in infants were low, and no infant pertussis deaths were reported. Despite a high number of imported measles cases, there was limited secondary transmission. The invasive meningococcal disease notification rate declined, and disease due to serogroup C remained low and stable.

CONCLUSION

Vaccine-preventable diseases were relatively well controlled in New South Wales in 2013, with declining or stable notification rates in most diseases compared with the previous year.

[Meningococcus B: control of two outbreaks by vaccination]

The issue of an effective vaccine against Meningococcus B (MenB) has been overcome by identifying, with the "reverse vaccinology" methodology, some antigens able of inducing a response to the majority of MenB strains circulating in the world. The new 4-components MenB vaccine (4CMenB) has been approved in Europe, Australia and Canada, and included in international pediatric immunization schedules: Australia, Canada, UK. In Italy, the first regions that have recommended vaccination against MenB were Basilicata and Puglia. The management of epidemics/outbreaks requires the implementation of a rapid response by health authorities in respect of a medical emergency with a high impact, even emotional, on the population, as recently demonstrated in two American universities. The declaration of outbreak in place has been followed in both contexts by the adoption of a procedure for the use of the 4CMenB vaccine not yet licensed in the USA. It was thus possible to organize interventions of active prophylaxis in the two campuses, establishing the first large-scale use of the new 4CMenB vaccine and achieving, in a relatively short time, high rates of vaccination coverage. With around 14,000 students immunized with at least one dose, no safety issues have been reported following immunization. Besides, to date there have been no cases in subjects who have received the vaccine. As a result of the two outbreaks described, FDA is now evaluating for the extension of the use of the 4CMenB vaccine in adolescents and young adults in USA.

Meningococcal serogroups A, C, W-135, and Y tetanus toxoid conjugate vaccine: a new conjugate vaccine against invasive meningococcal disease

Invasive meningococcal disease is a serious infection that occurs worldwide. It is caused by Neisseria meningitidis, of which six serogroups (A, B, C, W-135, X, and Y) are responsible for most infections. The case fatality rate of meningococcal disease remains high and can lead to significant sequelae. Vaccination remains the best strategy to prevent meningococcal disease. Polysaccharide vaccines were initially introduced in the late 1960s but their limitations (poor immunogenicity in infants and toddlers and hyporesponsiveness after repeated doses) have led to the development and use of meningococcal conjugate vaccines, which overcome these limitations. Two quadrivalent conjugated meningococcal vaccines – MenACWY-DT (Menactra^®) and MenACWY-CRM₁₉₇ (Menveo^®) – using diphtheria toxoid or a mutant protein, respectively, as carrier proteins have already been licensed in the US. Recently, a quadrivalent meningococcal vaccine conjugated to tetanus toxoid (MenACWY-TT; Nimenrix^®) was approved for use in Europe in 2012. The immunogenicity of MenACWY-TT, its reactogenicity and safety profile, as well as its coadministration with other vaccines are discussed in this review. Clinical trials showed that MenACWY-TT was immunogenic in children above the age of 12 months, adolescents, and adults, and has an acceptable reactogenicity and safety profile. Its coadministration with several other vaccines that are commonly used in children, adolescents, and adults did not affect the immunogenicity of MenACWY-TT or the coadministered vaccine, nor did it affect its reactogenicity and safety. Other studies are now ongoing in order to determine the immunogenicity, reactogenicity, and safety of MenACWY-TT in infants from the age of 6 weeks.