Quadrivalent Meningococcal Vaccine Research Articles

Statewide Outbreak of Neisseria meningitidis Serogroup Y, Sequence Type 1466 - Virginia, 2022-2024.

Invasive meningococcal disease (IMD) is a severe illness that can have devastating effects; outbreaks are uncommon in the United States. Vaccination is the preferred control measure for IMD outbreaks when a defined population at risk (e.g., college students or persons experiencing homelessness) can be identified. In August 2022, the Virginia Department of Health (VDH) began investigating an IMD outbreak in Virginia's Eastern Health Planning Region, prompted by the detection of four confirmed cases within 8 weeks. Clinical isolates available from three cases were characterized as Neisseria meningitidis serogroup Y, sequence type 1466. A subsequent statewide investigation identified 36 genetically related cases, including seven deaths (case fatality rate=19.4%) as of March 1, 2024. A majority of patients (63.9%) were in an age group (30-60 years) not generally considered at increased risk for IMD; 78.0% were non-Hispanic Black or African American. No common exposures, affiliations, or risk factors were identified, and a defined population could not be identified for vaccination. VDH recommended quadrivalent (serogroups A, C, W, and Y) meningococcal conjugate vaccination of a subset of close contacts of patients based on IMD risk factors and age range similar to that of patients with identified cases. IMD outbreaks might affect populations without established IMD risk factors. Lack of a well-defined population at risk might prompt exploration of novel control strategies, such as selective vaccination of close contacts.

Penbraya: A pentavalent meningococcal vaccine.

The FDA has licensed Penbraya (Pfizer), a pentavalent polysaccharide conjugate meningococcal vaccine, for prevention of invasive meningococcal disease caused by Neisseria meningitidis serogroups A, B, C, W, or Y (MenABCWY) in persons 10-25 years old. Penbraya is the only meningococcal vaccine that contains all five of these serogroups. Two quadrivalent polysaccharide conjugate meningococcal vaccines containing serogroups A, C, W, and Y (MenACWY; Menveo, MenQuadfi) and two meningococcal serogroup B vaccines (MenB; Bexsero, Trumenba) are available in the US.

EPH99 Public Health Impact of Replacing Monovalent and Quadrivalent Meningococcal Vaccines By Pentavalent Vaccine in the United States

EPH99 Public Health Impact of Replacing Monovalent and Quadrivalent Meningococcal Vaccines By Pentavalent Vaccine in the United States

1157. Immune Persistence and Booster Response of a Quadrivalent Meningococcal Conjugate Vaccine (MenACYW-TT) 5 Years After Primary Vaccination of Adults ≥59 Years of Age

Abstract Background MenACYW-TT (MenQuadfi®, Sanofi) is a quadrivalent (serogroups A, C, W, and Y) meningococcal tetanus toxoid conjugate vaccine. It is approved for use in persons aged ≥2 years in the US and persons aged ≥1 year in Europe and certain other countries; trials in infants as young as 6 weeks are ongoing. The second stage of a 2-stage study of MenACYW-TT, reported herein, evaluated immune persistence among older adults who received primary vaccination with either quadrivalent meningococcal polysaccharide vaccine (MSPV4) or MenACYW-TT five years earlier at age ≥ 56 years. The immunogenicity and safety of a MenACYW-TT booster dose given to this population were also evaluated. Methods This was a Phase 3, 2-stage, randomized, open-label, multi-center study (NCT04142242) of adults aged ≥59 years who participated in previous studies of MenACYW-TT vs MPSV4 (NCT01732627 and NCT02842866). The study was conducted in the US and Puerto Rico. Immune persistence and response were assessed with a serum bactericidal assay using human complement (hSBA). Safety data were collected for up to 30 days after booster vaccination. All analyses were descriptive. Results Of the initial study population (N=471), 70 adults participated in Stage II of the study. At 5 years post-primary vaccination, seroprotection (hSBA ≥ 1:8) rates (SPRs) and hSBA geometric mean titers (GMTs) declined in both MenACYW-TT- and MPSV4-primed subjects, with SPRs and hSBA GMTs for serogroups A, C, W, and Y trending higher in MenACYW-TT- vs MPSV4-primed subjects (Table 1). Thirty days after booster vaccination, hSBA GMTs and SPRs increased from pre-booster for all serogroups and were, along with seroresponse rates, higher in MenACYW-TT-primed subjects compared to MPSV4-primed subjects (Table 2). Rates of AEs following booster vaccination were similar regardless of priming vaccine. No safety concerns were identified. Conclusion Five years after primary vaccination, immune persistence tended to be greater for MenACYW-TT vs MPSV4. A MenACYW-TT booster was well tolerated and immunogenic in adults ≥ 61 years, when administered 5 years after primary vaccination with either MPSV4 or MenACYW-TT. Disclosures Corwin A. Robertson, MD, MPH, FACP, Sanofi: Sanofi employee|Sanofi: Sanofi's Employee|Sanofi: Stocks/Bonds Katherine Galarza, MD, Sanofi: Sanofi employee|Sanofi: Stocks/Bonds Alexandre Selmani, PhD, Sanofi: Sanofi employee|Sanofi: Stocks/Bonds Philipp Oster, MD, Sanofi: Sanofi employee

Immunogenicity and safety of a pentavalent meningococcal ABCWY vaccine in adolescents and young adults: an observer-blind, active-controlled, randomised trial

Immunogenicity and safety of a pentavalent meningococcal ABCWY vaccine in adolescents and young adults: an observer-blind, active-controlled, randomised trial

Safety and immunogenicity of quadrivalent meningococcal polysaccharide vaccine (MPV ACYW135) compared with quadrivalent meningococcal conjugate vaccine (Menactra®) in Malian children

ABSTRACT Affordable, polyvalent meningococcal vaccines are needed for use in emergency reactive immunization campaigns. A phase IV randomized, observer-blind, controlled study compared the safety and immunogenicity of a quadrivalent meningococcal polysaccharide vaccine (MPV-4, MPV ACYW135) and quadrivalent meningococcal ACWY conjugate vaccine (MCV-4, Menactra®). Healthy, 2- to 10-year-old children in Bamako, Mali, were randomized 1:1 to receive one dose of MPV-4 or MCV-4. Safety outcomes were evaluated for 6 months post-immunization. Immunogenicity for all serogroups was assessed for non-inferiority between MPV-4 and MCV-4 30 days post immunization by serum bactericidal antibody assay using baby rabbit complement (rSBA). From December 2020 to July 2021, 260 healthy subjects were consented and randomized. At Day 30 post-immunization, the proportions of subjects with rSBA titers ≥ 128 for all serogroups in the MPV-4 group were non-inferior to those in MCV-4 group. The proportions of subjects with rSBA ≥ 4-fold increase and rSBA titers ≥ 8 for all serogroups were similar among vaccine groups (P > .05). Geometric Mean Titers and Geometric Mean Fold Increases for all serogroups in both vaccine groups were similar (P > .05). Few local and systemic post-immunization reactions of similar severity and duration were observed within 7 days and were similar in both groups (P > .05). All resolved without sequelae. Unsolicited adverse events were similar in both groups regarding relationship to study vaccine, severity and duration. No serious adverse events were reported during the study period. MPV ACYW135 showed a non-inferior immunogenicity profile and a comparable reactogenicity profile to MCV-4 in Malian children aged 2–10 years. Clinical Trial Registration: NCT04450498.

Efficacy and safety of quadrivalent conjugate meningococcal vaccines: a systematic review and meta-analysis

Efficacy and safety of quadrivalent conjugate meningococcal vaccines: a systematic review and meta-analysis

Knowledge and Attitude of Meningitis Belt Country Passengers Arriving at King Abdul-Aziz International Airport – Jeddah, Saudi Arabia toward Ciprofloxacin as a Meningococcal Disease Prophylaxis

Abstract Meningitis belt countries of sub-Saharan Africa are highly endemic of Neisseria meningitides. Passengers traveling from meningitis belt countries and arriving in Jeddah, Saudi Arabia should receive one dose of ciprofloxacin upon their arrival if they are not vaccinated with the quadrivalent (ACYW) conjugate meningococcal vaccine. This study aims to assess the knowledge and attitude of those passengers regarding the preventive measures taken at the point of entry toward meningococcal disease. A cross-sectional study was conducted among 394 passengers who arrived from meningitis belt countries in Jeddah, Saudi Arabia from April to June 2022. The study shows that 51% of the participants were aware of the purpose of ciprofloxacin use, 64.7% of them were vaccinated with the meningococcal vaccine. About 77.2 % of the passengers were not informed about the preventive measures regarding meningococcal disease and the obligation of receiving ciprofloxacin if they are not vaccinated with conjugate type. The study finding demonstrates that there is a lack of information among the passengers who are arriving from meningitis belt countries regarding the preventive measures for meningococcal disease and it should be conveyed to them before the issuance of the visa in their home countries. Keywords: Meningitis Belt Countries, Neisseria meningitidis, Polysaccharide meningococcal vaccine, Conjugate meningococcal vaccine, Ciprofloxacin.

Immunogenicity and safety of a quadrivalent meningococcal conjugate vaccine (MenACYW-TT) administered as a booster to adults aged ≥59 years: A phase III randomized study

ABSTRACT This 2-stage Phase III study (NCT04142242) of a recently licensed quadrivalent meningococcal tetanus toxoid-conjugate vaccine (MenACYW-TT) assessed the safety and immunogenicity of a booster dose in older adults (≥59 years) primed with either MenACYW-TT or a quadrivalent meningococcal polysaccharide vaccine (MPSV4). Immune persistence of MenACYW-TT and MPSV4 after primary vaccination was also evaluated. During Stage I, the participants administered MPSV4 (n = 165) or MenACYW-TT (n = 236) 3 years previously were randomized 9:2 to receive either a MenACYW-TT booster or to have blood drawn for persistence only. Participants primed with MPSV4 or MenACYW-TT 6–7 years previously had blood drawn for antibody persistence only. A serum bactericidal assay using human complement was used to measure functional antibodies against each serogroup at baseline and, for those receiving a booster, 30 days post-vaccination (D30). Proportions of participants with seroresponse (post-vaccination titers ≥1:16 when baseline titers <1:8 or ≥ 4-fold increase when baseline titers ≥1:8) were determined. Safety data were collected up to D30. Seroresponse rates for all serogroups at D30 ranged from 49.2% to 60.8% in the MPSV4-primed group, and 79.3–93.1% in the MenACYW-TT-primed group. MenACYW-TT induced sufficient seroresponses in each primed group. Geometric mean titers (GMTs) for serogroups C, W, and Y remained or trended higher than pre-vaccination levels at both 3 and 6–7 years after primary vaccination, indicating immune persistence. Safety outcomes were comparable between groups. A MenACYW-TT booster was immunogenic and well tolerated in participants aged ≥59 years regardless of previous quadrivalent meningococcal vaccine received. The greatest immune responses occurred in those primed with MenACYW-TT.

Descriptive epidemiology of age at HPV vaccination: Analysis using the 2020 NIS-Teen

ABSTRACT Human papillomavirus (HPV) vaccination uptake in the United States remains suboptimal, and continues to trail that of tetanus, diphtheria, and acellular pertussis (Tdap) vaccination and quadrivalent meningococcal conjugate vaccination (MCV4). This is despite these three vaccines all being recommended for routine adolescent use within the 2005–2006 time period. One strategy to improve HPV vaccination is starting the vaccine series at the first opportunity – currently as young as 9 years of age. Little is known about the epidemiology of age at HPV vaccination, and the frequency of vaccination occurring at 9–10 years of age. Using 2020 National Immunization Survey-Teen (NIS-Teen) data, we analyzed age at HPV vaccine initiation and proportion of initiators completing the HPV vaccine series relative to age at initiation. Overall, 4.0% of US adolescents initiated HPV vaccination at 9–10 years of age, with higher initiation among younger birth cohorts (4.8% for 13-year-olds and 5.1% for 14-year-olds) than older cohorts (3.1% for both 16 and 17 year-olds). Age cohorts maximized HPV vaccine completion after 3–4 years. Among those initiating at ages 9–10, 93% of 13-year-olds completed the series. Among those initiating at 11–12, completion rates rose from 66% among 13-year-olds to 90.2% among 16-year-olds. Among those initiating at age 13–14, completion rose from 61% among 15-year-olds to 84.9% among 17-year-olds. This manuscript serves as a starting point of comparison for future epidemiologic evaluations of HPV vaccination at the first opportunity.

123. The change of meningococcal carriage rate and serogroup among military trainees since the introduction of meningococcal vaccine, and the genetic characterization of the carriage isolates

Abstract Background Monovalent meningococcal conjugate vaccines against serogroups A or C have resulted in significant reduction of pharyngeal carriage rates against the vaccine serogroups. However, the effect of the quadrivalent meningococcal conjugate vaccine on meningococcal carriage has not yet been evaluated. Methods We assessed changes in pharyngeal carriage rates of Neisseria meningitidis after introduction of the quadrivalent meningococcal conjugate vaccine in Korean military trainees. Two rounds of oropharyngeal swabs of Korean military trainees were obtained, at the beginning and the end of the army training period. The first oropharyngeal swabs were collected prior to vaccination; the second round was performed 5 weeks later. Results In 2013, the overall N. meningitidis carriage rate was higher at the end of the training period (13.8%, 60 of 434 participants) than upon entry into military service (8.9%, 39 of 434 participants). Although the carriage rates of nongroupable and serogroup X isolates increased over the 5-week interval, carriage of the serogroup strains included in the quadrivalent meningococcal vaccine was reduced, from 7 to 2 isolates, after vaccination. However, in 2014, the overall carriage rate of N. meningitidis was significantly lower at the end of the training period (5.2%, 23 of 443 participants) than on entry into military service (12.6%, 56 of 443 participants) (p = 0.028). Carriage of vaccine serogroups isolates was significantly decreased, compared to that of non-vaccine serogroup B over the 5-week interval. Carriage isolates belonging to the ST-178, ST-31 and ST-41/44 were frequently identified clonal complex. Meningococcal carriage rate before and after Meningococcal vaccination in Korean military trainees Conclusion Meningococcal vaccination in Korean military trainees could lead to reduce pharyngeal carriage rates of vaccine serogroup meningococci. Therefore, the quadrivalent meningococcal conjugate vaccine is likely to prevent carriage acquisition of meningococci in closed populations such as military trainees. Disclosures All Authors: No reported disclosures.

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

ABSTRACT 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.

Preclinical development of the quadrivalent meningococcal (ACYW) tetanus toxoid conjugate vaccine, MenQuadfi®

Bacterial capsular polysaccharide vaccines are generally poorly immunogenic in infants and older adults. The immunogenicity of capsular polysaccharide vaccines can be improved by conjugating them to immunogenic carrier proteins. One of the most recently licensed conjugate vaccines is the quadrivalent meningococcal vaccine with serogroups A, C, Y, and W conjugated to a tetanus toxoid protein carrier (MenACYW-TT; MenQuadfi, Sanofi Pasteur, Swiftwater, PA, USA). MenACYW-TT was developed to induce optimal immune responses against each of the meningococcal serogroups A, C, W, and Y, and across all age groups, especially infants and older adults (those aged ≥ 50 years). Here, we detail the early iterative vaccine development approach taken, whereby many different ‘small-scale’ conjugate vaccine candidates were prepared and examined for immunogenicity in a mouse model to identify the most immunogenic vaccine. Additional insights from phase I clinical studies informed further optimization of the vaccine candidates by tailoring their conjugation parameter attributes for the optimal immune response in humans. The parameters studied included: different carrier proteins [PR]; polysaccharide [PS] sizes; conjugation chemistries [linker vs. no-linker; lattice vs. neoglycoprotein; activation/derivatization levels]; conjugate size; PS:PR loading ratio; percent free PS; percent free PR; and O-acetylation content. The lead quadrivalent conjugate vaccine (polysaccharides of > 50 kDa size conjugated to TT at a high PS:PR ratio via reductive amination for serogroups C, W and Y, and carbonyldiimidazole/adipic acid dihydrazide linker chemistry for serogroup A) empirically identified from the extensive preclinical studies, was ultimately confirmed by the robust antibody responses observed in all age groups in the various clinical studies, including in the most challenging infant and older adult age groups, and subsequently led to the licensed formulation.Graphical abstract

Meningococcal Disease in Pediatric Age: A Focus on Epidemiology and Prevention.

Meningococcal disease is caused by Neisseria meningitidis; 13 serogroups have been identified and differentiated from each other through their capsular polysaccharide. Serotypes A, B, C, W, X, and Y are responsible for nearly all infections worldwide. The most common clinical manifestations are meningitis and invasive meningococcal disease, both characterized by high mortality and long-term sequelae. The infection rate is higher in children younger than 1 year and in adolescents, who are frequently asymptomatic carriers. Vaccination is the most effective method of preventing infection and transmission. Currently, both monovalent meningococcal vaccines (against A, B, and C serotypes) and quadrivalent meningococcal vaccines (against serogroups ACYW) are available and recommended according to local epidemiology. The purpose of this article is to describe the meningococcal vaccines and to identify instruments that are useful for reducing transmission and implementing the vaccination coverage. This aim could be reached by switching from the monovalent to the quadrivalent vaccine in the first year of life, increasing vaccine promotion against ACYW serotypes among adolescents, and extending the free offer of the anti-meningococcal B vaccine to teens, co-administering it with others proposed in the same age group. Greater awareness of the severity of the disease and increased health education through web and social networks could represent the best strategies for promoting adhesion and active participation in the vaccination campaign. Finally, the development of a licensed universal meningococcal vaccine should be another important objective.

Annals for Educators - March 2022.

Annals for Educators - March 2022.

Meningococcal Vaccination:: An Update on Meningococcal Vaccine Recommendations for the Primary Care Physician.

Neisseria meningitidis is an aerobic, gram-negative, diplococcus bacterium that is a leading cause of meningitis and sepsis in the United States. Particularly at-risk groups include those with complement deficiencies, people using complement inhibitors, individuals with anatomic or functional asplenia, patients with HIV infection and travelers to endemic countries. There are currently three quadrivalent meningococcal vaccines (Serogroups A, C, W, Y) and two recombinant serogroup B vaccines available for use in the United States, and recommendations for vaccine use have changed rapidly in the past 10-15 years. This article summarizes updated ACIP recommendations for meningococcal vaccination for the primary care provider.

04. Immunogenicity and Safety of a Quadrivalent Meningococcal Conjugate Vaccine (MenACYW-TT) Administered in Meningococcal Vaccine-Naive Participants Across a Broad Age Range (2-55 Years) in Japan

BackgroundMenACYW-TT [MenQuadfi®] is a quadrivalent meningococcal conjugate vaccine, licensed for use in ages 2 years and older in USA. The vaccine is also licensed in ages 12 months and older in EU and certain other countries. We evaluated the safety and immunogenicity of MenACYW-TT compared to a licensed quadrivalent conjugate meningococcal vaccine (MenACWY-DT [Menactra®]) in Japanese children, adolescents and adults (2-55 years of age).MethodsA phase III modified double-blind, randomized study (NCT04368429) to evaluate the immunogenicity and safety of a single dose of MenACYW-TT versus MenACWY-DT was conducted in 360 participants (ratio 1:1) between ages 2 and 55 years in Japan. Serum bactericidal assays with human complement (hSBA) were used to measure antibodies against vaccine serogroups at baseline (Day 0) and 30 days post-vaccination (D30). Safety data were collected up to 30 days post-vaccination.ResultsNon-inferiority of immune responses for all four serogroups, based on percentages of participants achieving hSBA vaccine seroresponse as primary endpoint, was demonstrated for MenACYW-TT compared to MenACWY-DT at Day 30 in comparison to baseline: 85.6% vs 65.4% for serogroup A, 96.6% vs 62.6% for serogroup C, 87.4% vs 49.2% for serogroup W, and 97.7% vs 63.5% for serogroup Y. The proportions of individuals with hSBA titers ≥ 1:8 following MenACYW-TT administration were higher than those after MenACWY-DT administration for serogroups C (98.9% vs 81.0%), W (99.4% vs 91.1%) and Y (100 % vs 89.4%) and comparable for serogroup A (96.6% vs 92.7%). The hSBA GMTs were higher following administration of MenACYW-TT for all four serogroups. Immunogenicity results in participants 10 to 17 years of age and ≥ 18 years of age were comparable to those in the whole population (2-55 years). The safety profiles of MenACYW-TT and MenACWY-DT were comparable. There were no immediate adverse events (AEs), no AEs leading to study discontinuation, and no vaccine-related serious adverse events reported in the study.ConclusionMenACYW-TT vaccine was well tolerated and demonstrated a non-inferior immune response compared to that for the licensed MenACWY-DT vaccine when administered as a single dose to meningococcal vaccine-naïve children, adolescents, and adults in Japan.Disclosures Osamu Matsuoka, MD, Sanofi Pasteur (Scientific Research Study Investigator, Research Grant or Support) Mugen Ujiie, MD, Sanofi Pasteur (Scientific Research Study Investigator, Research Grant or Support) Hitoshi Kikuchi, MD, Sanofi Pasteur (Scientific Research Study Investigator)Sanofi Pasteur (Research Grant or Support) Danaya Chansinghakul, MD, Sanofi Pasteur (Employee) Takahiro Inoue, MSc, Sanofi Pasteur (Employee) Kucku Varghese, PhD, Sanofi Pasteur (Employee) Nuchra Sirisuphmitr, MSc, Sanofi Pasteur (Employee) Tomoyuki Hashiguchi, MSc, Sanofi Pasteur (Employee) Betzana Zambrano, MD, Sanofi Pasteur (Employee) Takahiro Nakama, MD, Sanofi Pasteur (Employee) Carina Frago, MD, Sanofi Pasteur (Employee, Shareholder) Emilia Jordanov, MD, Sanofi Pasteur (Employee, Shareholder) Mandeep S. Dhingra, MD, Sanofi Pasteur (Employee, Shareholder)

1046. Immunogenicity and Safety of a Quadrivalent Meningococcal Conjugate Vaccine (MenACYW-TT) Administered as a Booster to Adults ≥ 59 Years of Age

Abstract Background MenACYW-TT (MenQuadfi®, Sanofi) is a quadrivalent (serogroups A, C, W, and Y) meningococcal tetanus toxoid conjugate vaccine. It was recently approved for use in persons aged ≥ 2 years in the US and persons aged ≥ 1 year in Europe and certain other countries; trials in infants as young as 6 weeks are ongoing. This study evaluated seroresponse after a MenACYW-TT booster given to adults who received either quadrivalent meningococcal polysaccharide vaccine (MSPV4) or MenACYW-TT three years earlier at age ≥ 56 years. Immune persistence up to 7 years after primary vaccination was also evaluated. Methods This was a Phase 3 randomized, open-label study (NCT04142242) of adults aged ≥ 59 years who participated in previous studies of MenACYW-TT vs MPSV4 (NCT01732627 and NCT02842866). The study was conducted in the US and Puerto Rico. Immune response and persistence were assessed with a serum bactericidal assay using human complement (hSBA). Sufficiency of the vaccine seroresponse was considered demonstrated if the lower limit of the 1-sided 97.5% CI for the percentage of subjects with an hSBA vaccine seroresponse against serogroups A, C, W and Y was &amp;gt; 40%. Safety data were collected up to 30 days after booster vaccination. Results A total of 471 persons were enrolled. Sufficiency of a MenACYW-TT booster was demonstrated for MPSV4- and for MenACYW-TT-primed subjects. hSBA seroresponse rates were higher among MenACYW-TT- vs MPSV4-primed subjects (79.3%–93.1% vs 49.2%–60.8%, respectively). Three to 7 years after primary vaccination, hSBA geometric mean titers (GMTs) and seroprotection rates (SPRs) declined in both MenACYW-TT- and MPSV4-primed subjects, with hSBA GMTs and SPRs for serogroups C, W, and Y generally remaining higher for MenACYW-TT- vs MPSV4-primed subjects; those for serogroup A were similar regardless of priming vaccine. Rates of adverse events following a MenACYW-TT booster were similar between MenACYW-TT- and MPSV4-primed subjects. No safety concerns were identified. Conclusion A MenACYW-TT booster was well tolerated and immunogenic when administered to either MPSV4- or MenACYW-primed adults aged ≥ 59 years. Up to 7 years after primary vaccination, immune persistence for serogroups C, W, and Y tended to be greater for MenACYW-TT vs MPSV4. Disclosures Corwin A. Robertson, MD, MPH, FACP, Sanofi Pasteur (Employee, Other Financial or Material Support, Stockholder) Alexandre Selmani, PhD, Sanofi Pasteur (Employee) Katherine Galarza, MD, Sanofi Pasteur (Employee) Philipp Oster, MD, Sanofi Pasteur (Employee, Stockholder)

Hospitalizations related to meningococcal infection in Spain from 1997 to 2018

BackgroundBaseline hospitalization, mortality, and in-hospital fatality rates for meningococcal infection are required to evaluate preventive interventions, such as the inclusion of the conjugated quadrivalent meningococcal vaccine and serogroup B based protein vaccines.MethodsAll meningococcal infection–related hospitalizations in any diagnostic position in Spain from 1st January 1997 through 31st December 2018 were analysed. The annual hospitalization rate, mortality rate and case-fatality rate were calculated.ResultsThe average hospitalization rate for meningococcal infection was 1.64 (95% CI 1.61 to 1.66) hospitalizations per 100,000 inhabitants during the study period and significantly decreased from 1997 to 2018. Hospitalizations for meningococcal infection decreased significantly with age and were concentrated in children under 5 years of age (46%). The hospitalization rates reached 29 per 100,000 and 24 per 100,000 children under 1 and 2 years of age, respectively. The in-hospital case-fatality rate was 7.45% (95% CI 7.03 to 7.86). Thirty percent of the deaths occurred in children under 5 years of age, and more than half occurred in adults. The case fatality rate increased significantly with age (p < 0.001).ConclusionIt is necessary to maintain epidemiological surveillance of meningococcal infection to determine the main circulating serogroups involved, track their evolution, and evaluate preventive measures whose effectiveness must be assessed in all age groups.

National and State-Level Composite Completion of Recommended Vaccines Among Adolescents in the United States, 2015–2018

BackgroundRoutine adolescent vaccination recommendations in the United States include tetanus, diphtheria, and acellular pertussis, quadrivalent meningococcal conjugate vaccine, and human papillomavirus vaccines. Although coverage for these individual vaccines is known, limited data are available on composite completion for all three vaccines. MethodsThis cross-sectional analysis of pooled 2015–2018 National Immunization Survey–Teen data used logistic regression to estimate model-adjusted composite vaccination completion nationally and by state among United States adolescents aged 17 years. National Immunization Survey–Teen data were combined with state-level data to estimate a multilevel model identifying factors associated with composite vaccination completion. ResultsThe pooled model-adjusted composite vaccination completion was 30.6% (95% confidence interval [CI], 30.13%–31.04%) nationally, varying from 11.3% in Idaho (6.91%–17.95%) to 56.4% (49.81%–62.82%) in Rhode Island. Individual-level factors with the greatest impact on composite completion were having a provider's recommendation for human papillomavirus vaccination (odds ratio, 3.24; 95% CI, 2.76–3.80) and a check-up visit at age 16–17 years (odds ratio, 2.35; 95% CI, 1.80–3.07), with other individual-level factors associated with completion including being Medicaid insured, female, Hispanic, or non-Hispanic black. State-level quadrivalent meningococcal conjugate vaccination mandates were also associated with an increased likelihood of composite vaccination completion (odds ratio, 1.64; 95% CI, 1.16–2.33). ConclusionsFewer than one-third of 17-year-old individuals have completed all three recommended vaccines, with rates varying by state. Although this study identified implementable strategies to improve composite completion, additional research is needed to further understand factors associated with adolescent vaccination completion.