A Phase II, randomized, immunogenicity and safety study of a quadrivalent meningococcal conjugate vaccine, MenACYW-TT, in healthy adolescents in the United States

Immunogenicity and Safety of a Quadrivalent Meningococcal Conjugate Vaccine Versus Nimenrix in Healthy Adolescents: A Randomized Phase IIIb Multicenter Study

INTRODUCTION

Many immunization programs in Europe recommend quadrivalent meningococcal vaccinations, which are often administered concomitantly with other vaccines. We compared the immune response of a tetanus toxoid conjugated quadrivalent meningococcal vaccine (MenACYW-TT, MenQuadfi®) with another quadrivalent meningococcal conjugate vaccine (MCV4-TT; Nimenrix®) when administered alone or concomitantly with Tdap-IPV and 9vHPV vaccines in adolescents.

METHODS

In this phase IIIb trial, healthy adolescents (MenC-naïve or MenC-primed before 2 years of age) from Spain, Italy, Hungary, and Singapore were randomized in a 3:3:2 ratio to receive either MenACYW-TT or MCV4-TT alone, or MenACYW-TT concomitantly with 9vHPV and Tdap-IPV. The primary objective was to demonstrate the non-inferiority of the seroprotection rate (human serum bactericidal assay [hSBA] titer ≥ 1:8) to serogroups A, C, W, and Y 30 days post-vaccination with a single dose of MenACYW-TT or MCV4-TT. Secondary objectives included describing hSBA titers for the four serogroups before and 1 month following vaccination and according to MenC priming status.

RESULTS

A total of 463 participants were enrolled (MenACYW-TT, n = 173; MCV4-TT, n = 173; MenACYW-TT/9vHPV/Tdap-IPV n = 117). Non-inferiority based on seroprotection was demonstrated for MenACYW-TT versus MCV4-TT for all serogroups. Immune responses were comparable whether MenACYW-TT was administered alone or concomitantly with Tdap-IPV and 9vHPV. Post-vaccination hSBA GMTs were higher in MenACYW-TT vs. MCV4-TT for serogroups C, Y, and W and comparable for serogroup A. The percentages of participants with an hSBA vaccine seroresponse were higher in MenACYW-TT vs. MCV4-TT for all serogroups. For serogroup C, higher GMTs were observed in both MenC-naïve or -primed participants vaccinated with MenACYW-TT vs. MCV4-TT. Seroprotection and seroresponse were higher in MenC-naïve participants vaccinated with MenACYW-TT vs. MCV4-TT and comparable in MenC-primed. The safety profiles were comparable between groups and no new safety concerns were identified.

CONCLUSIONS

These data support the concomitant administration of MenACYW-TT with 9vHPV and Tdap-IPV vaccines in adolescents.

TRIAL REGISTRATIONS

Clinicaltrials.gov, NCT04490018; EudraCT: 2020-001665-37; WHO: U1111-1249-2973.

Structured Benefit-Risk Assessment of a New Quadrivalent Meningococcal Conjugate Vaccine (MenACYW-TT) in Individuals Ages 12 Months and Older

INTRODUCTION

A favorable benefit-risk balance is required to support licensure of biologics, in keeping with regulatory agencies' evolving recommendations, including the United States Food and Drugs Administration. We present a structured semi-quantitative benefit-risk analysis of MenACYW-TT, a quadrivalent meningococcal conjugate vaccine against Neisseria meningitidis serogroups, A, C, W and Y versus licensed comparators in individuals aged ≥ 12 months.

METHODS

We used data from six MenACYW-TT clinical trials, stratified by age group, versus licensed vaccines: toddlers (12-23 months; Nimenrix® [MCV4-TT]), children (2-9 years; Menveo® [MCV4-CRM]), adolescents (10-17 years; MCV4-CRM or Menactra® [MCV4-DT]), adults (18-55 years; MCV4-DT) and older adults (≥ 56 years; Menomune®-A/C/Y/W-135 [MPSV4]). Eight benefit (seroresponse and seroprotection for A, C, W and Y) and five risk outcomes (any and grade 3 solicited injection site and systemic reactions, and serious adverse events) were measured at Day 30 after initial vaccination. Analyses were conducted by baseline vaccination status (meningococcal vaccine-naïve or vaccine-primed).

RESULTS

MenACYW-TT showed favorable seroresponse and seroprotection among vaccine-naïve participants aged ≥ 2 years, against all serogroups, compared with MCV4-CRM, MCV4-DT and MPSV4. In vaccine-naïve toddlers, there was a favorable effect for serogroup C, but no difference between MenACYW-TT and MCV4-TT for serogroups A, Y and W. A favorable effect for MenACYW-TT against serogroup C was observed in all vaccine-naïve and combined vaccine-naïve and MenC conjugate vaccine-primed groups. For all risk criteria, there were no differences between MenACYW-TT and MCV4s in toddlers, children, adolescents and adults. Results for solicited injection site and systemic reactions favored MPSV4 in older adults.

CONCLUSIONS

The benefit-risk profile for MenACYW-TT showed favorable seroresponse and seroprotection in individuals aged ≥ 2 years and no difference in risk criteria between MenACYW-TT and MCV4s. MenACYW-TT may provide an alternative to the standard-of-care for meningococcal disease prevention in those aged ≥ 12 months.

Quadrivalent meningococcal tetanus toxoid-conjugate booster vaccination in adolescents and adults: phase III randomized study

BACKGROUND

The immunogenicity and safety of a booster dose of tetanus toxoid-conjugate quadrivalent meningococcal vaccine (MenACYW-TT), alone or co-administered with MenB vaccine, were assessed in healthy 13-25-year olds who received MenACYW-TT or a CRM-conjugate vaccine (MCV4-CRM) 3-6 years earlier.

METHODS

This phase IIIb open-label trial (NCT04084769) evaluated MenACYW-TT-primed participants, randomized to receive MenACYW-TT alone or with a MenB vaccine, and MCV4-CRM-primed participants who received MenACYW-TT alone. Functional antibodies against serogroups A, C, W and Y were measured using human complement serum bactericidal antibody assay (hSBA). The primary endpoint was vaccine seroresponse (post-vaccination titers ≥1:16 if pre-vaccination titers <1:8; or a ≥4-fold increase if pre-vaccination titers ≥1:8) 30 days post booster. Safety was evaluated throughout the study.

RESULTS

The persistence of the immune response following primary vaccination with MenACYW-TT was demonstrated. Seroresponse after MenACYW-TT booster was high regardless of priming vaccine (serogroup A: 94.8% vs 93.2%; C: 97.1% vs 98.9%; W: 97.7% vs 98.9%; and Y; 98.9% vs 100% for MenACWY-TT-primed and MCV4-CRM-primed groups, respectively). Co-administration with MenB vaccines did not affect MenACWY-TT immunogenicity. No vaccine-related serious adverse events were reported.

CONCLUSIONS

MenACYW-TT booster induced robust immunogenicity against all serogroups, regardless of the primary vaccine received, and had an acceptable safety profile.

IMPACT

A booster dose of MenACYW-TT induces robust immune responses in children and adolescents primed with MenACYW-TT or another MCV4 (MCV4-DT or MCV4-CRM), respectively. Here, we demonstrate that MenACYW-TT booster 3-6 years after primary vaccination induced robust immunogenicity against all serogroups, regardless of the priming vaccine (MenACWY-TT or MCV4-CRM), and was well tolerated. Persistence of the immune response following previous primary vaccination with MenACYW-TT was demonstrated. MenACYW-TT booster with MenB vaccine co-administration did not affect MenACWY-TT immunogenicity and was well tolerated. These findings will facilitate the provision of broader protection against IMD particularly in higher-risk groups such as adolescents.

Efficacy and Safety of Quadrivalent Conjugate Meningococcal Vaccines: A Systematic Review and Meta-Analysis

Over the last decades, different quadrivalent antimeningococcal vaccine formulations (diphteria toxoid conjugate, MenACWY-D; tetanus toxoid conjugate, MenACWY-TT; CRM₁₉₇ protein conjugate, MenACWY-CRM) have been developed. However, their availability varies, both in terms of authorized formulations and of inclusion in vaccination schedules. Furthermore, several countries include only the monovalent meningococcal C (MenC) vaccine in their immunization programmes. Finally, there is currently no updated systematic review that directly compares the MenACWY formulations. Thus, we summarized the evidence on efficacy and safety through four parallel, independent systematic literature reviews with meta-analysis which included randomized controlled trials comparing the abovementioned vaccines. A total of 16 studies have been included. In terms of efficacy, MenACWY-TT outperformed MenACWY-D and MenACWY-CRM for A, W-135, and Y serogroups, while no significant difference was found for serogroup C. Furthermore, we did not find significant differences in efficacy between MenC and MenACWY-TT. Regarding the safety, we were able to perform a quantitative analysis only between MenACWY-TT and MenC, finding no significant differences. Similarly, among the different MenACWY formulations no relevant differences were identified. These findings suggest that MenACWY-TT could be preferable to other formulations to improve current vaccination programs and to better develop future immunization policies.

Fully Liquid MenACWY-CRM Vaccine: Results from an Integrated Safety Analysis

INTRODUCTION

The currently licensed quadrivalent MenACWY-CRM conjugate vaccine presentation consists of two vials (lyophilized MenA and liquid MenCWY) to be reconstituted before injection. A new fully liquid, single-vial formulation has been developed to simplify administration and prevent reconstitution errors. We present pooled safety data from two randomized, controlled, observer-blind phase 2b clinical trials, in which the fully liquid presentation was compared with the licensed presentation.

METHODS

This is a post hoc analysis of two studies, in which safety data from participants aged 10-40 years who received one dose of either liquid MenACWY-CRM (1337 participants; MenACWY liquid group) or licensed MenACWY-CRM (1332 participants; MenACWY licensed group) were pooled. Frequencies were calculated for solicited adverse events (AEs) during 7 days post-vaccination and unsolicited AEs, including medically attended AEs and serious AEs (SAEs), during the 6-month safety follow-up period. Analysis results are presented by vaccine group, overall and by age category (10-17 and 18-40 years).

RESULTS

Overall, AEs solicited for collection during the first 7 days after vaccination were reported by similar percentages of participants (69.2%, MenACWY liquid; 68.2%, MenACWY licensed), and were generally mild/moderate in intensity. Solicited local AEs were reported by 46.0% of the MenACWY liquid group and 43.5% of the MenACWY licensed group and solicited systemic AEs by 55.2 and 54.1%, respectively. During the 6-month post-vaccination period, unsolicited AEs were reported by 32.2 and 31.2% of the MenACWY liquid group and MenACWY licensed group, respectively, and medically attended AEs by 18.6 and 17.3%, respectively. Overall, 14 participants in each group (1.0 and 1.1%, respectively) reported SAEs, none of which was considered vaccine-related by the investigator. The safety profiles of both MenACWY-CRM presentations were similar for each age group and overall.

CONCLUSIONS

This pooled analysis shows the safety profile of fully liquid MenACWY-CRM is comparable with that of the currently licensed vaccine presentation.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov Identifiers: NCT03652610 (August 29, 2018), NCT03433482 (14 February 2018).

Immunogenicity and safety of MenACWY-TT, a quadrivalent meningococcal tetanus toxoid conjugate vaccine recently licensed in the United States for individuals ≥2 years of age

Vaccination offers the best way to prevent invasive meningococcal disease (IMD). As demonstrated in countries with national immunization programs (NIPs) against IMD, meningococcal conjugate vaccines have contributed to significant declines in incidence. Since some meningococcal vaccines are associated with modest immunogenicity in infants, possible immunological interference upon concomitant administration with some pediatric vaccines, and administration errors resulting from improper reconstitution, opportunities for improvement exist. A quadrivalent conjugate vaccine, MenQuadfi® (Meningococcal [Serogroups A, C, Y, and W] Conjugate Vaccine; Sanofi, Swiftwater, Pennsylvania), was approved in 2020 for the prevention of IMD caused by meningococcal serogroups A, C, W, and Y in individuals ≥2 years of age in the United States. Five pivotal studies and one ancillary study supported approval in the United States; clinical trials in infants are ongoing. Data on the immunogenicity and safety of this vaccine are presented, and its potential value in clinical practice is discussed.

Comparing the meningococcal serogroup C immune response elicited by a tetanus toxoid conjugate quadrivalent meningococcal vaccine (MenACYW-TT) versus a quadrivalent or monovalent C tetanus toxoid conjugate meningococcal vaccine in healthy meningococcal vaccine-naïve toddlers: A randomised, controlled trial

MenACYW-TT (MenQuadfi®) is a quadrivalent meningococcal tetanus toxoid conjugate vaccine licensed in Europe for use in individuals ≥12 months. This study assessed whether serogroup C immune responses with MenACYW-TT were at least non-inferior, or superior, to those of quadrivalent meningococcal ACWY (MCV4-TT; Nimenrix®) and monovalent meningococcal C (MenC-TT; NeisVac-C®) vaccines in toddlers (12–23 months). In this modified, double-blind Phase III study (NCT03890367), 701 toddlers received one dose of MenACYW-TT (n = 230), MCV4-TT (n = 232) or MenC-TT (n = 239). Serum bactericidal assays with human (hSBA) and baby rabbit (rSBA) complement were used to measure anti-meningococcal serogroup C antibodies at baseline and 30 days post-vaccination. A sequential statistical approach was used for primary and secondary objectives. For the primary objectives, superiority of serogroup C was assessed in terms of hSBA seroprotection rates (defined as titers ≥1:8) and GMTs for MenACYW-TT compared to MCV4-TT, and rSBA GMTs compared to MenC-TT. The safety of all vaccines within 30 days post-vaccination was described. When administered as a single dose to meningococcal vaccine-naïve healthy toddlers the superiority of the MenACYW-TT serogroup C immune response versus MCV4-TT was demonstrated for hSBA GMTs (ratio 16.3 [12.7–21.0]) and seroprotection (difference 10.43% [5.68–16.20]); and versus MenC-TT in terms of rSBA GMTs (ratio 1.32 [1.06–1.64]). The safety profiles of a single dose of MenACYW-TT, MCV4-TT and MenC-TT were similar. In meningococcal vaccine-naïve toddlers, MenACYW-TT induced superior immune responses to serogroup C versus MCV4-TT in terms of hSBA seroprotection and GMTs and versus MenC-TT in terms of rSBA GMTs.

Safety and immunogenicity of an investigational quadrivalent meningococcal tetanus toxoid conjugate vaccine (MenACYW-TT) co-administered with routine pediatric vaccines in infants and toddlers: A Phase II study

BACKGROUND

The MenACYW-TT conjugate vaccine is approved for prevention of invasive meningococcal disease (IMD) as a single dose in individuals ≥2 years of age in the United States and ≥12 months in EU and some other countries. This Phase II study evaluated the safety and immunogenicity of this vaccine and of concomitant pediatric vaccines in infants/toddlers (6 weeks-15 months of age).

METHODS

Five schedules of the MenACYW-TT conjugate vaccine were evaluated in the United States: 2, 4, 6, and 12 months; 2, 4, 6, and 15 months; 2, 4, and 12 months; 6 and 12 months; and 12 months alone. Routine pediatric vaccines (DTaP-IPV/Hib, PCV7/PCV13, MMR, and varicella) were administered per approved schedules. Proportions of participants with serum bactericidal antibodyassay with human complement (hSBA) titers ≥1:4 and ≥1:8, SBA with baby rabbit complement (rSBA) titers ≥1:8 and ≥1:128, and immune responses against concomitant vaccines were determined.

RESULTS

Tenderness and irritability were the most frequent solicited injection site and systemic reactions. Similar proportions of participants achieved an hSBA titer ≥1:8 for all four serogroups regardless of whether 2 or 3 doses were administered in the first year of life. Following a second-year dose, 91-100% of participants achieved the threshold for all 4 serogroups in all schedules regardless of the number of doses in the first year of life. Similar responses were seen with rSBA. Immunogenicity and safety profile of concomitant vaccines was similar whether the MenACYW-TT conjugate vaccine was administered or not.

CONCLUSION

MenACYW-TT conjugate vaccine administered with pediatric vaccines is safe and immunogenic regardless of the schedule and does not affect the immunogenicity or safety of the concomitant vaccines.

CLINICAL TRIAL REGISTRY

NCT01049035.

Meningococcal disease and vaccination in college students

Neisseria meningitidis is a bacterial pathogen capable of causing rapidly progressing illness from nonspecific symptoms to end-organ failure or death in a matter of hours to days. Despite the availability of meningococcal vaccines, there remains a notable disease incidence peak among individuals aged 18-19 years, with college students at increased risk for disease relative to non-college students. Between 2007 and 2017, as many as one in five colleges in the United States experienced an outbreak of meningococcal disease at their own or a nearby institution. Evidence-based strategies to promote meningococcal vaccination among students can be adapted for the college setting, but barriers exist that limit widespread implementation of these strategies by colleges. In this article, we review meningococcal disease characteristics and epidemiology among US college students, vaccination indications and coverage levels among US college students, as well as college vaccination policies and practices that can impact students' vaccine uptake.

A novel vaccine to prevent meningococcal disease beyond the first year of life: an early review of MenACYW-TT

INTRODUCTION

Although quadrivalent meningococcal conjugate vaccines have been effective in preventing invasive meningococcal disease (IMD) caused by serogroups A, C, W, and Y across age groups from infants to adults, data on their efficacy and safety in adults ≥56 years of age are lacking. Moreover, multiple available quadrivalent conjugate vaccines require reconstitution prior to administration, introducing the potential for error. A novel quadrivalent meningococcal conjugate vaccine, MenACYW-TT (MenQuadfi®) was approved in 2020 for use in individuals ≥12 months of age as a single dose in the European Union and some other countries and in individuals ≥2 years of age in the United States.

AREAS COVERED

The findings of Phase II/III studies that included >6600 individuals and evaluated the immunogenicity and safety of MenACYW-TT beyond the first year of life are comprehensively summarized and discussed.

EXPERT OPINION

Extensive data on immunogenicity and safety, co-administration with routine vaccines, elicitation of robust booster responses, and significantly higher Men C responses versus monovalent MenC or MenACWY standard-of-care vaccines in toddlers suggest that MenACYW-TT may be suitable for inclusion in National Immunization Programs (NIPs) globally. The authors provide their perspectives on the clinical use of MenACYW-TT across age groups from toddlers through adults.

MenQuadfi (MenACWY-TT): A New Vaccine for Meningococcal Serogroups ACWY

OBJECTIVE

This article reviews data encompassing the pharmacology, efficacy, and safety of MenACWY-TT (MenQuadfi), a conjugate vaccine to prevent meningococcal disease from serogroups A, C, W, Y.

DATA SOURCES

A literature review was conducted in PubMed, MEDLINE, and ClinicalTrials.gov from inception up to July 2021, using the search terms MenQuadfi, meningococcal ACWY vaccine, MCV4, and menacwy. Articles from reference lists were included to identify potential relevant literature.

STUDY SELECTION AND DATA EXTRACTION

Data were limited to randomized phase II and III clinical studies published in the English language, evaluating the efficacy and safety of MenACWY-TT. Animal studies and studies not utilizing MenACWY-TT were excluded.

DATA SYNTHESIS

One phase II and 4 phase III randomized clinical studies, enrolling approximately 7700 participants, aged 2 years to 97 years old found that MenACWY-TT was noninferior when compared to established MenACWY vaccines, as measured by surrogate immunogenicity end points. In studies evaluating primary dose vaccination, conducted in those aged 2 to 97 years of age, the difference in seroresponse rates, reported by the lower bound of the 95% CI, was (A) 1.1% to 14.8%, (C) 21% to 42.2%, (Y) 7.7% to 24.6%, and (W) 8.9% to 22.5%.

RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE

Despite the low incidence of meningococcal disease in the United States, meningococcal disease causes significant morbidity and mortality if not prevented.

CONCLUSION

MenACWY-TT is noninferior to currently approved quadrivalent meningococcal vaccines and shows similar immunogenicity and safety as both an initial vaccine for prevention as well as a booster dose.

Safety of vaccines used for routine immunization in the United States: An updated systematic review and meta-analysis

BACKGROUND

Understanding the safety of vaccines is critical to inform decisions about vaccination. Our objective was to conduct a systematic review of the safety of vaccines recommended for children, adults, and pregnant women in the United States.

METHODS

We searched the literature in November 2020 to update a 2014 Agency for Healthcare Research and Quality review by integrating newly available data. Studies of vaccines that used a comparator and reported the presence or absence of key adverse events were eligible. Adhering to Evidence-based Practice Center methodology, we assessed the strength of evidence (SoE) for all evidence statements. The systematic review is registered in PROSPERO (CRD42020180089).

RESULTS

Of 56,603 reviewed citations, 338 studies reported in 518 publications met inclusion criteria. For children, SoE was high for no increased risk of autism following measles, mumps, and rubella (MMR) vaccine. SoE was high for increased risk of febrile seizures with MMR. There was no evidence of increased risk of  intussusception with rotavirus vaccine at the latest follow-up (moderate SoE), nor of diabetes (high SoE). There was no evidence of increased risk or insufficient evidence for key adverse events for newer vaccines such as 9-valent human papillomavirus and meningococcal B vaccines. For adults, there was no evidence of increased risk (varied SoE) or insufficient evidence for key adverse events for the new adjuvanted inactivated influenza vaccine and recombinant adjuvanted zoster vaccine. We found no evidence of increased risk (varied SoE) for key adverse events among pregnant women following tetanus, diphtheria, and acellular pertussis vaccine, including stillbirth (moderate SoE).

CONCLUSIONS

Across a large body of research we found few associations of vaccines and serious key adverse events; however, rare events are challenging to study. Any adverse events should be weighed against the protective benefits that vaccines provide.

Immunogenicity and safety of a quadrivalent meningococcal tetanus toxoid-conjugate vaccine administered concomitantly with other paediatric vaccines in toddlers: a phase III randomised study

Invasive meningococcal disease has high morbidity and mortality, with infants and young children among those at greatest risk. This phase III, open-label, randomised study in toddlers aged 12-23 months evaluated the immunogenicity and safety of meningococcal tetanus toxoid-conjugate vaccine (MenACYW-TT), a tetanus toxoid conjugated vaccine against meningococcal serogroups A, C, W and Y, when coadministered with paediatric vaccines (measles, mumps and rubella [MMR]; varicella [V]; 6-in-1 combination vaccine against diphtheria, tetanus, pertussis, polio, hepatitis B and Haemophilus influenzae type b [DTaP-IPV-HepB-Hib] and pneumococcal conjugate vaccine [PCV13])(NCT03205371). Immunogenicity to each meningococcal serogroup was assessed by serum bactericidal antibody assay using human complement (hSBA). Vaccine safety profiles were described up to 30 days post-vaccination. A total of 1183 participants were enrolled. The proportion with seroprotection (hSBA ≥1:8) to each meningococcal serogroup at Day 30 was comparable between the MenACYW-TT and MenACYW-TT + MMR + V groups (≥92 and ≥96%, respectively), between the MenACYW-TT and MenACYW-TT + DTaP-IPV-HepB-Hib groups (≥90% for both) and between the MenACYW-TT and MenACYW-TT + PCV13 groups (≥91 and ≥84%, respectively). The safety profiles of MenACYW-TT, and MMR + V, DTaP-IPV-HepB-Hib, and PCV13, with or without MenACYW-TT, were generally comparable. Coadministration of MenACYW-TT with paediatric vaccines in toddlers had no clinically relevant effect on the immunogenicity and safety of any of the vaccines.

Immunogenicity and safety of a quadrivalent meningococcal tetanus toxoid-conjugate vaccine (MenACYW-TT) vs. a licensed quadrivalent meningococcal tetanus toxoid-conjugate vaccine in meningococcal vaccine-naïve and meningococcal C conjugate vaccine-primed toddlers: a phase III randomised study

Vaccination remains the best strategy to reduce invasive meningococcal disease. This study evaluated an investigational tetanus toxoid-conjugate quadrivalent meningococcal vaccine (MenACYW-TT) vs. a licensed tetanus toxoid-conjugate quadrivalent meningococcal vaccine (MCV4-TT) (NCT02955797). Healthy toddlers aged 12–23 months were included if they were either meningococcal vaccine-naïve or MenC conjugate (MCC) vaccine-primed (≥1 dose of MCC prior to 12 months of age). Vaccine-naïve participants were randomised 1:1 to either MenACYW-TT (n = 306) or MCV4-TT (n = 306). MCC-primed participants were randomised 2:1 to MenACYW-TT (n = 203) or MCV4-TT (n = 103). Antibody titres against each of the four meningococcal serogroups were measured by serum bactericidal antibody assay using the human complement. The co-primary objectives of this study were to demonstrate the non-inferiority of MenACYW-TT to MCV4-TT in terms of seroprotection (titres ≥1:8) at Day 30 in both vaccine-naïve and all participants (vaccine-naïve and MCC-primed groups pooled). The immune response for all four serogroups to MenACYW-TT was non-inferior to MCV4-TT in vaccine-naïve participants (seroprotection: range 83.6–99.3% and 81.4–91.6%, respectively) and all participants (seroprotection: range 83.6–99.3% and 81.4–98.0%, respectively). The safety profiles of both vaccines were comparable. MenACYW-TT was well-tolerated and demonstrated non-inferior immunogenicity when administered to MCC vaccine-primed and vaccine-naïve toddlers.

Vaccines against Meningococcal Diseases

Neisseria meningitidis is the main cause of meningitis and sepsis, potentially life-threatening conditions. Thanks to advancements in vaccine development, vaccines are now available for five out of six meningococcal disease-causing serogroups (A, B, C, W, and Y). Vaccination programs with monovalent meningococcal serogroup C (MenC) conjugate vaccines in Europe have successfully decreased MenC disease and carriage. The use of a monovalent MenA conjugate vaccine in the African meningitis belt has led to a near elimination of MenA disease. Due to the emergence of non-vaccine serogroups, recommendations have gradually shifted, in many countries, from monovalent conjugate vaccines to quadrivalent MenACWY conjugate vaccines to provide broader protection. Recent real-world effectiveness of broad-coverage, protein-based MenB vaccines has been reassuring. Vaccines are also used to control meningococcal outbreaks. Despite major improvements, meningococcal disease remains a global public health concern. Further research into changing epidemiology is needed. Ongoing efforts are being made to develop next-generation, pentavalent vaccines including a MenACWYX conjugate vaccine and a MenACWY conjugate vaccine combined with MenB, which are expected to contribute to the global control of meningitis.

Safety and Immunogenicity of a Quadrivalent Meningococcal Conjugate Vaccine in Healthy Meningococcal-Naïve Children 2-9 Years of Age: A Phase III, Randomized Study

BACKGROUND

Invasive meningococcal disease is a major cause of meningitis in children. An investigational meningococcal (serogroups A, C, Y, and W) tetanus toxoid conjugate vaccine (MenACYW-TT) could offer protection against invasive meningococcal disease in this population. This phase III study assessed the immunogenicity and safety of MenACYW-TT in children compared with a licensed quadrivalent meningococcal vaccine conjugated with diphtheria protein CRM197 (MenACWY-CRM).

METHODS

Healthy children 2-9 years of age in the United States, including Puerto Rico, were randomized (1:1) to receive MenACYW-TT (n = 499) or MenACWY-CRM (n = 501) (NCT03077438). Meningococcal antibody titers to the 4 vaccine serogroups were measured using a serum bactericidal antibody assay with human complement (hSBA) before and at day 30 after vaccination. Noninferiority between the vaccine groups was assessed by comparing seroresponse rates (postvaccination titers ≥1:16 when prevaccination titers were <1:8, or ≥4-fold increase if prevaccination titers were ≥1:8) to the 4 serogroups at day 30. Safety was monitored.

RESULTS

The proportion of participants achieving seroresponse at day 30 in the MenACYW-TT group was noninferior to the MenACWY-CRM group (A: 55.4% vs. 47.8%; C: 95.2% vs. 47.8%; W: 78.8% vs. 64.1%; Y: 91.5% vs. 79.3%, respectively). Geometric mean titers for serogroups C, W, and Y were higher with MenACYW-TT than for MenACWY-CRM. Both vaccines were well-tolerated and had similar safety profiles.

CONCLUSIONS

MenACYW-TT was well-tolerated in children and achieved noninferior immune responses to MenACWY-CRM against each of the 4 vaccine serogroups.

Meningococcal Vaccination: Recommendations of the Advisory Committee on Immunization Practices, United States, 2020

This report compiles and summarizes all recommendations from CDC's Advisory Committee on Immunization Practices (ACIP) for use of meningococcal vaccines in the United States. As a comprehensive summary and update of previously published recommendations, it replaces all previously published reports and policy notes. This report also contains new recommendations for administration of booster doses of serogroup B meningococcal (MenB) vaccine for persons at increased risk for serogroup B meningococcal disease. These guidelines will be updated as needed on the basis of availability of new data or licensure of new meningococcal vaccines. ACIP recommends routine vaccination with a quadrivalent meningococcal conjugate vaccine (MenACWY) for adolescents aged 11 or 12 years, with a booster dose at age 16 years. ACIP also recommends routine vaccination with MenACWY for persons aged ≥2 months at increased risk for meningococcal disease caused by serogroups A, C, W, or Y, including persons who have persistent complement component deficiencies; persons receiving a complement inhibitor (e.g., eculizumab [Soliris] or ravulizumab [Ultomiris]); persons who have anatomic or functional asplenia; persons with human immunodeficiency virus infection; microbiologists routinely exposed to isolates of Neisseria meningitidis; persons identified to be at increased risk because of a meningococcal disease outbreak caused by serogroups A, C, W, or Y; persons who travel to or live in areas in which meningococcal disease is hyperendemic or epidemic; unvaccinated or incompletely vaccinated first-year college students living in residence halls; and military recruits. ACIP recommends MenACWY booster doses for previously vaccinated persons who become or remain at increased risk.In addition, ACIP recommends routine use of MenB vaccine series among persons aged ≥10 years who are at increased risk for serogroup B meningococcal disease, including persons who have persistent complement component deficiencies; persons receiving a complement inhibitor; persons who have anatomic or functional asplenia; microbiologists who are routinely exposed to isolates of N. meningitidis; and persons identified to be at increased risk because of a meningococcal disease outbreak caused by serogroup B. ACIP recommends MenB booster doses for previously vaccinated persons who become or remain at increased risk. In addition, ACIP recommends a MenB series for adolescents and young adults aged 16-23 years on the basis of shared clinical decision-making to provide short-term protection against disease caused by most strains of serogroup B N. meningitidis.