Comparison of Immune Responses to Two Quadrivalent Meningococcal Conjugate Vaccines (CRM197 and Diphtheria Toxoid) in Healthy Adults

A randomized study to evaluate the safety and immunogenicity of a pentavalent meningococcal vaccine

A randomized, active-controlled, double-blind, first-in-human, phase 1 study was conducted in healthy Korean adults to evaluate the safety, tolerability, and immunogenicity of EuNmCV-5, a new pentavalent meningococcal vaccine targeting serogroups A, C, W, X, and Y. Sixty participants randomly received a single dose of either EuNmCV-5 or MenACWY-CRM, a quadrivalent vaccine containing serogroups A, C, W, and Y. Safety was assessed through monitoring anaphylactic reactions, adverse events for 28 days, and serious adverse events over 180 days. Immunogenicity was assessed via rabbit complement-dependent serum bactericidal antibody (rSBA) assay. EuNmCV-5 was safe, well-tolerated, and elicited a substantial antibody titer increase. The seroprotection rates exceeded 96.7%, and the seroconversion rates were over 85% for all the targeted serogroups. It showed higher seroconversion rates against serogroups A and C (p = 0.0016 and 0.0237, respectively) and elicited a substantial increase in GMT for all targeted serogroups compared to the MenACWY-CRM.ClinicalTrials.gov identifier: NCT05739292.

Effectiveness of Meningococcal Vaccines at Reducing Invasive Meningococcal Disease and Pharyngeal Neisseria meningitidis Carriage: A Systematic Review and Meta-analysis

BACKGROUND

Invasive meningococcal disease (IMD), caused by Neisseria meningitidis, leads to significant morbidity and mortality worldwide. This review aimed to establish the effectiveness of meningococcal vaccines at preventing IMD and N. meningitidis pharyngeal carriage.

METHODS

A search within PubMed, Embase, Scopus, and unpublished studies up to 1 February 2020 was conducted.

RESULTS

After removal of duplicates, 8565 studies were screened and 27 studies included. Protection was provided by meningococcal C vaccines for group C IMD (odds ratio [OR], 0.13 [95% confidence interval {CI}, .07-.23]), outer membrane vesicle (OMV) vaccines against group B IMD (OR, 0.35 [95% CI, .25-.48]), and meningococcal A, C, W, Y (MenACWY) vaccines against group ACWY IMD (OR, 0.31 [95% CI, .20-.49]). A single time series analysis found a reduction following an infant 4CMenB program (incidence rate ratio, 0.25 [95% CI, .19-.36]). Multivalent MenACWY vaccines did not reduce carriage (relative risk [RR], 0.88 [95% CI, .66-1.18]), unlike monovalent C vaccines (RR, 0.50 [95% CI, .26-.97]). 4CMenB vaccine had no effect on group B carriage (RR, 1.12 [95% CI, .90-1.40]). There was also no reduction in group B carriage following MenB-FHbp vaccination (RR, 0.98 [95% CI, .53-1.79]).

CONCLUSIONS

Meningococcal conjugate C, ACWY, and OMV vaccines are effective at reducing IMD. A small number of studies demonstrate that monovalent C conjugate vaccines reduce pharyngeal N. meningitidis carriage. There is no evidence of carriage reduction for multivalent MenACWY, OMV, or recombinant MenB vaccines, which has implications for immunization strategies.

CLINICAL TRIALS REGISTRATION

CRD42018082085 (PROSPERO).

Health care professionals' preference for a fully liquid, ready-to-use hexavalent vaccine in Spain

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Biosafety devices are needed to safely administer vaccines.

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Use of “ready-to-use” vaccines can avoid biological accidents.

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Majority of nurses showed concerns about using lyophilized vaccines.

Vaccination is an effective health intervention for the prevention of infectious diseases. This study aims to evaluate the response provided by nurses toward the use of ready-to-use (RTU) formulations of hexavalent vaccines and measures to prevent errors during the vaccination process. This observational, descriptive, cross-sectional study took place from March to May 2018. It included 201 interviews with nurses from health centers in Madrid (70), Murcia (59), and Andalusia (72), who had administered RTU vaccines in the last 12 months. Approximately 91.6% of nurses provided a positive feedback for the use of RTU vaccines. The most significant concerns experienced by nurses were during the preparation and administration of vaccines; 84.1% versus 18.9% of nurses felt that the risk of making mistakes was lower while using RTU vaccines compared with non-reconstituted (lyophilized) vaccines, and 74.1% versus 22.4% of nurses felt ease at preparing RTU vaccines compared with lyophilized vaccines. A total of 66.7% of nurses believed that there were risks associated with the preparation of lyophilized vaccines (administration risk [42.8%] and risk of needle injury [42.3%]). Risk percentages reduced to 4% and 9.5%, respectively, with the use of the RTU vaccines. Therefore, nurses adopted an average of seven steps to reduce the risk of errors. The average time saved during the administration of the vaccines was 1.1 min. In summary, nurses highlighted the need for administering vaccines using RTU formulations for ensuring the safety of the recipients, preventing errors, and saving time during the vaccination process.

Post-Marketing Surveillance Observational Study of Quadrivalent Meningococcal Diphtheria Toxoid Conjugate Vaccine (MenACWY-DT, MCV4/Menactra®) in the Republic of Korea, 2014-2019

Background

Invasive meningococcal disease is a notifiable disease in the Republic of Korea. The meningococcal (groups A, C, Y, and W) polysaccharide diphtheria toxoid conjugate vaccine (MenACWY-DT, Menactra^®) was licensed in the Republic of Korea in 2014. This post-marketing surveillance (PMS) observational study aims to assess the safety of MenACWY-DT administration of routine clinical care to individuals aged 9–23 months as a two-dose series at least 3 months apart and to individuals 2–55 years as a single dose.

Methods

The PMS observational study (NCT02864927) included participants aged 9 months to 55 years and who were given MenACWY-DT during routine healthcare visits. The study participants were followed-up for up to 30 days following vaccination (additional time was allowed for the visit or phone call to be conducted). Study outcomes included solicited and unsolicited adverse reactions, unexpected adverse events, and serious adverse events (SAEs).

Results

A total of 640 participants 9–23 months of age and 671 participants 2–55 years of age were eligible for safety analysis. Overall, AEs were reported by 35.3% of participants aged < 2 years and 45% of participants aged 2–55 years. Solicited adverse reactions were reported by 21.4% and 17.4% of participants aged < 2 years and 2–55 years, respectively. Unsolicited adverse reactions were reported by 26.1% and 37.9%, respectively. No vaccine-related SAEs occurred during the study. The AEs reported in Korean population were consistent with the known safety profile of MenACWY-DT, and most were of grade 1–2 in severity.

Conclusions

This study did not detect any unanticipated or new safety findings of concern with MenACWY-DT in either of the study age groups, and provides reassurance that MenACWY-DT can be used as part of routine immunization care for the prevention of invasive meningococcal disease.

Trial Registration

ClinicalTrials.gov Identifier, NCT02864927