Safety and immunogenicity of a novel quadrivalent meningococcal CRM-conjugate vaccine given concomitantly with routine vaccinations in infants

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.

A phase II, single-center, randomized, double-blind, parallel control clinical study evaluating the immunogenicity and safety of a two-dose schedule of serogroups ACYW meningococcal polysaccharide conjugate vaccine

BACKGROUND

This was a single-center, randomized, double-blind, parallel control study evaluating the immunogenicity and safety of a two-dose schedule of serogroups ACYW meningococcal polysaccharide conjugate vaccine with tetanus toxoid (TT) conjugate protein, in infants and toddlers of 3-35 months old.

METHOD

720 participants were stratified according to the age of 3-5 months old, 6-11 months old, and 12-35 months old and randomly assigned with an equal ratio to two different dose groups, i.e., 40- and 20-μg doses. Blood samples were taken from all participants before the first vaccination and 30 days after the full-course vaccination to detect the serogroups ACYW meningococcal antibodies. All adverse events occurred within 30 days after vaccination of each dose, and serious adverse events occurred within six months after full-course vaccination were collected for safety evaluation. This study was registered at the China drug trial registration with the identifier CTR 20182031.

RESULTS

After 30 days of full-course vaccination, 92.78 % (95 % CI: 85.70 %-100.00 %) showed the immune response against all serogroups in both high-dose and low-dose groups by rabbit serum bactericidal antibody assay (rSBA) and the geometric mean titer (GMT) of all serogroups showed a high level (74.6-505.8, 95 % CI: 56.4-615.7). However, no significant difference between different dose groups was observed (P > 0.05). The common local and systemic adverse events in both groups were redness (3 %-7%), and fever (26 %-65 %), respectively. In addition, the grade 3 adverse event related to the vaccine was fever (1.67 %-12.50 %). No serious adverse event was reported to be associate with the vaccination.

CONCLUSION

The serogroups ACYW meningococcal polysaccharide conjugate vaccine was safe and effective in the population aged 3-35 months. The vaccine efficacy and safety of the 20-μg dose group were not less than that of the 40-μg dose group.

A Decade of Fighting Invasive Meningococcal Disease: A Narrative Review of Clinical and Real-World Experience with the MenACWY-CRM Conjugate Vaccine

The quadrivalent A, C, W and Y meningococcal vaccine conjugated to nontoxic mutant of diphtheria toxin (MenACWY-CRM) has been licensed since 2010 for the prevention of invasive meningococcal disease (IMD), an uncommon but life-threatening condition. Here, we summarize the experience accrued with MenACWY-CRM during the first decade since its licensure, by providing an overview of clinical trials investigating the safety, immunogenicity and co-administration of MenACWY-CRM with other vaccines as well as presenting real-world evidence regarding the impact of MenACWY-CRM vaccination on carriage and IMD incidence. MenACWY-CRM has demonstrated an acceptable clinical safety profile across a wide range of age groups; no safety concerns have been reported in special populations, such as immunocompromised infants and toddlers, or pregnant women. MenACWY-CRM has also been proven to be immunogenic in various age groups and geographic settings, and a booster dose has been shown to elicit strong anamnestic responses in all studied populations, irrespective of the vaccine used for priming. With no clinically relevant vaccine interactions reported, MenACWY-CRM is being conveniently integrated into existing vaccination programs for various age and risk groups; this possibility of co-administration helps improving vaccine coverage and streamlining the healthcare process of fighting preventable infectious diseases. Vaccination of adolescents and adults has been proven to reduce nasopharyngeal carriage for serogroups C, W and Y, which is an important element in reducing transmission. Real-world evidence indicates that MenACWY-CRM can reduce IMD incidence even in high-exposure groups. When combined with vaccines against serogroup B meningococci, MenACWY-CRM can offer protection against five of the most common serogroups responsible for IMD, which is an important advantage in the continuously evolving landscape of meningococcal serogroup epidemiology.

Invasive meningococcal disease is an uncommon but life-threatening infection that appears as meningitis and/or sepsis. It is caused by Neisseria meningitidis, a bacteria commonly present in the throat or nose. Vaccination with MenACWY-CRM (Menveo, GSK) helps to prevent invasive meningococcal disease caused by four of the most common N. meningitidis serogroups (A, C, W and Y). This vaccine has been licensed for 10 years: we summarized here all available evidence gathered since the vaccine has been available in general practice, from clinical development to real-world experience. Information gained during clinical trials of MenACWY-CRM confirms that vaccination is well tolerated, has an acceptable safety profile and would induce significant protection when given to individuals of various ages such as infants, toddlers, children, adolescents and adults, and when administered at the same time as routine or traveler vaccinations as well as vaccines against serogroup B meningococci (4CMenB). Vaccination with MenACWY-CRM has been shown to decrease the number of serogroup C, W and Y meningococci found in the nose and throat in adolescents and adults as well as the occurrence of invasive meningococcal disease in a high-exposure population from a real-world setting. MenACWY-CRM can conveniently be integrated into most of the existing vaccination schedules for various age and risk groups. When combined with vaccination against serogroup B meningococci, MenACWY-CRM can contribute to providing protection against five of the most common serogroups responsible for invasive meningococcal disease.

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.

Systematic literature review on the safety and immunogenicity of rotavirus vaccines when co-administered with meningococcal vaccines

This study is aimed to review the published evidence on safety, immunogenicity, and efficacy of rotavirus vaccines when co-administered with meningococcal vaccines in infants. A systematic literature search was performed in four databases containing peer-reviewed articles and conference abstracts. In total, twelve articles were included in the review; 11 provided information on safety and five on the immunogenicity of rotavirus vaccines following co-administration. No paper was found on efficacy. Additional routine vaccines were administered in all studies. The safety analysis was mainly focused on fever, vomiting, diarrhea, intussusception, and changes in eating habits. Overall, safety profiles and immune responses associated with rotavirus vaccination were comparable between infants co-administered with rotavirus and meningococcal vaccines and infants receiving rotavirus vaccines without meningococcal vaccines. Although data are limited, co-administration of rotavirus and meningococcal vaccines does not appear to interfere with the safety or immunogenicity of rotavirus vaccines.

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.

Results from a large post-marketing safety surveillance study in the Republic of Korea with a quadrivalent meningococcal CRM-conjugate vaccine in individuals aged 2 months-55 years

The quadrivalent meningococcal conjugate vaccine MenACWY-CRM is approved in the Republic of Korea for use in individuals from 2 months of age. This single-arm, open-label, observational, multicenter, post-marketing study (NCT01766206) assessed the safety of MenACWY-CRM vaccine administered according to local clinical practice. A total of 3939 individuals aged 2 months–55 years provided safety data post-vaccination; the analysis was conducted on the per-protocol set (3920 participants). Solicited and unsolicited adverse events (AEs) were collected over 7 days post-vaccination and medically-attended AEs (MAAEs) and serious AEs (SAEs) over 29 days post-vaccination. Among recorded solicited AEs, injection site AEs were reported by 21.38% of participants, with tenderness/pain being most frequent across age groups; systemic AEs were reported in 13.95% of participants, with irritability (in ˂6-year-olds), headache and myalgia (in ≥6 year-olds) being the most frequently reported. Most solicited AEs were mild or moderate in nature. The percentage of participants reporting unsolicited AEs varied in the study population, i.e. 12.56% in participants aged 2–23 months and 3.18% in those ≥2 years of age. Overall, less than 22% of unsolicited AEs were considered as related to vaccination. MAAEs (10.89% of participants) were mostly mild; 2.82% were considered as related to vaccination. Three (0.46%) and 5 (0.15%) SAEs (none vaccination-related) occurred in participants aged 2–23 months and 2–55 years, respectively. No deaths were reported. The safety profile for MenACWY-CRM in this post-marketing surveillance was consistent with observations from studies conducted during the vaccine’s clinical development, with no new safety concerns.

Co-administration of vaccines: a focus on tetravalent Measles-Mumps-Rubella-Varicella (MMRV) and meningococcal C conjugate vaccines

Simultaneous administration of different vaccines is a strategy to increase the possibility to receive vaccines at appropriate age, safely and effectively, reducing the number of sessions and allowing a more acceptable integration of new vaccines into National Immunization Programs (NIPs). Co-administration can be performed when there are specific indications in the Summary of Product Characteristics (SmPC) of the vaccines; but, in absence of these indications, the practice is possible if there are no specific contraindications nor scientific evidence to discourage simultaneous administration.

The aim of this work is to review the safety and efficacy of co-administration of the tetravalent measles, mumps, rubella, and varicella (MMRV) and the meningococcal C (Men C) conjugate vaccines after 12 months of age.

Several studies demonstrated that MMRV and Men C conjugate vaccines can be administered concomitantly without a negative impact on the safety and immunogenicity of either vaccines, inducing highly immunogenic responses.

Safety of quadrivalent meningococcal conjugate vaccine in infants and toddlers 2 to 23-months old

INTRODUCTION

The quadrivalent meningococcal conjugate vaccine MenACWY-CRM is recommended for 2-23 month-old infants/toddlers at increased risk for meningococcal disease. This study adds to the current knowledge of MenACWY-CRM safety among this age group in a clinical care setting.

METHODS

Kaiser Permanente Southern California members aged 2-23 months who received MenACWY-CRM between July 2014 and June 2017 were included. Electronic health records were searched for emergency department (ED) and hospitalization encounters, and diagnoses associated with these visits up to 6 months after each dose.

RESULTS

There were 138 infants/toddlers who received MenACWY-CRM, with 59.4% being African American and 66.7% receiving only one dose. Most infants either had a high-risk condition (i.e., anatomic/functional asplenia or DiGeorge syndrome) (42.0%), or a travel indication (54.3%). The incidence rate of ED visits was 0.6/person-year (95% confidence interval [CI]: 0.5-0.8), 0.4/person-year (CI: 0.3-0.5) for hospitalizations, and 0.1/person-year (CI: 0.1-0.3) for ED to hospital transfers. Overall, 29.0% of recipients had an incident diagnosis in the ED or hospital setting. Fever and acute upper respiratory infections were the most common diagnoses, with 46 out of 47 diagnoses occurring among infants with high-risk conditions.

CONCLUSIONS

Data from this descriptive observational study do not suggest safety concerns associated with MenACWY-CRM when used as part of clinical care of 2-23 month-old infants/toddlers indicated for vaccination.

MenACWY-CRM conjugate vaccine booster dose given 4-6 years after priming: Results from a phase IIIb, multicenter, open label study in adolescents and adults

BACKGROUND

Vaccination strategies against bacterial meningitis vary across countries. In the United States, a single dose of quadrivalent meningococcal conjugate vaccine (MenACWY) is recommended at 11-12 years of age, with a booster dose approximately 5 years later. We assessed immune responses to a booster dose of MenACWY-CRM vaccine after priming with MenACWY-CRM or MenACWY-D vaccines in adolescents and adults.

METHODS

In this phase IIIb, multicenter, open-label study, healthy 15-55-year-olds, who received MenACWY-CRM (N = 301) or MenACWY-D (N = 300) 4-6 years earlier or were meningococcal vaccine-naïve (N = 100), received one MenACWY-CRM vaccine dose. Immunogenicity was evaluated pre-vaccination, 3 or 5 days post-vaccination (sampling subgroups), and 28 days post-vaccination by serum bactericidal activity assay using human complement (hSBA). After vaccination, participants were monitored for 7 days for reactogenicity, 29 days for unsolicited adverse events (AEs), and 181 days for serious AEs and medically-attended AEs.

RESULTS

Sufficiency of the immune response to a MenACWY-CRM booster dose was demonstrated; the lower limit of the 1-sided 97.5% confidence interval for percentages of participants with hSBA seroresponse at 28 days post-vaccination was >75% for each serogroup in those primed with either the MenACWY-CRM or MenACWY-D vaccine. Seroresponse was observed in ≥93.24% of primed participants and ≥35.87% of naïve participants 28 days post-vaccination. At 5 days post-booster, among primed participants, hSBA titers ≥1:8 were achieved in ≥47.14% of participants for MenA and in ≥85.52% of participants for MenC, MenW and MenY, and 3.25- to 8.59-fold increases in hSBA geometric mean titers against each vaccine serogroup were observed. No safety concerns were raised throughout the 6-month follow-up period.

CONCLUSIONS

A booster dose of the MenACWY-CRM vaccine induced a robust and rapid anamnestic response in adolescents and adults, irrespectively of either MenACWY-CRM or MenACWY-D vaccine administered 4-6 years earlier, with an acceptable clinical safety profile. ClinicalTrials.gov registration: NCT02986854.

One-year antibody persistence and safety of a 4-dose schedule of MenACWY-CRM in healthy infants from South Korea

Purpose

Results from a post-marketing study to generate evidence on 1-year antibody persistence and safety following vaccination of infants from South Korea with the quadrivalent meningococcal conjugate vaccine MenACWY-CRM.

Materials and Methods

In this phase IV, open-label, multi-center study (NCT02446691), 128 infants received MenACWY-CRM at ages 2, 4, 6, and 12 months. One-year antibody persistence following the full vaccination course was evaluated (primary objective) for the four meningococcal serogroups (Men) by serum bactericidal activity assay using human or rabbit complement (hSBA/rSBA). Immune responses at 1-month post-vaccination and safety were also assessed.

Results

The percentage of children with hSBA titers ≥8 ranged between 94% (MenA) and 100% (MenY/W) 1-month post-vaccination, and from 39% (MenA) to 89% (MenY) 1-year post-vaccination. At least 99% and 92% of children had rSBA titers ≥8 and ≥128 against each meningococcal serogroup, 1-month post-vaccination. One-year post-vaccination, the percentage of children with rSBA titers ≥8 and ≥128 ranged from 54% (MenC) to 99% (MenA) and from 30% (MenC) to 98% (MenA). Geometric mean titers declined from 1-month to 1-year post-vaccination, when they varied between 6.8 (MenA) and 53.6 (MenW) by hSBA and between 17.2 (MenC) and 2,269.5 (MenA) by rSBA. At least one solicited and unsolicited adverse event was reported for 79% and 66% of children. Of 36 serious adverse events reported, none were vaccination-related.

Conclusion

Antibody persistence (hSBA/rSBA titers ≥8) was determined in 39%-99% of children 1 year after a 4-dose MenACWY-CRM series during infancy, with an acceptable clinical safety profile.

Antibody persistence and booster response following MenACWY-CRM vaccination in children as assessed by two different assay methods

BACKGROUND

The quadrivalent meningococcal conjugate vaccine MenACWY-CRM has been shown to be immunogenic and well-tolerated in infants and toddlers. We evaluated antibody persistence for up to 4 years after vaccination with MenACWY-CRM in the first years of life and response to a booster dose administered at 60 months of age.

METHODS

This was phase 3b, open-label, multicenter extension trial (NCT01148017). We assessed by hSBA and rSBA the persistence of antibody responses to serogroups ACWY in 203 healthy 60-month-olds receiving 4 doses of MenACWY-CRM during infancy (ACWY-4 group), or 2 doses at 12/13 and 15 months or 1 dose at 18 months of age (ACWY-2 group). We administered a MenACWY-CRM dose to 224 primed and 45 naïve 60-month-olds and evaluated safety and antibody response 1 month later.

RESULTS

Antibody persistence measured by both assays was higher in primed than naïve 60-month-olds. The percentages of primed children with hSBA titers ≥8 was low for serogroup A (6-25%) and moderate for serogroups C (27-43%), Y (69-74%) and W (56-69%). For all serogroups, hSBA antibody geometric mean titers (GMTs) tended to be higher in the ACWY-2 than the ACWY-4 group. Post-booster/single dose, ≥96% of primed and ≥73% of naïve children had hSBA titers ≥8 against each serogroup, and hSBA GMTs were higher in primed children. The booster dose was well-tolerated and no safety concern was identified. We further assessed persistence using rSBA across different age groups and detected no overall correlation between rSBA and hSBA titers.

CONCLUSIONS

Primary vaccination of infants/toddlers with MenACWY-CRM resulted in moderate antibody persistence against serogroups C, W and Y for up to 4 years after the last priming dose. Regardless of priming schedule, a MenACWY-CRM booster dose at 60 months of age induced a robust immune response against all serogroups and was well-tolerated in all children.

An update of clinical experience with the quadrivalent meningococcal ACWY-CRM conjugate vaccine

INTRODUCTION

Menveo, quadrivalent meningococcal ACWY-CRM conjugate vaccine, was first licensed in 2010 in the United States and has a long track record of immunogenicity and safety in all age groups, including infants from 2 months of age.

AREAS COVERED

This review presents clinical and post-marketing experience with MenACWY-CRM from 32 studies conducted in 20 countries that included individuals aged from 2 months to 75 years.

EXPERT COMMENTARY

This decade has seen an increased number of countries reporting serogroup W ST-11 clonal complex outbreaks of invasive meningococcal disease. As infant vaccination programs targeting the meningococcus are reevaluated, the role of quadrivalent meningococcal vaccines including MenACWY-CRM will be expanded. MenACWY-CRM was immunogenic in all populations and age groups studied, regardless of country of origin. MenACWY-CRM can be coadministered with many routinely used infant, toddler and adolescent vaccines, and traveler vaccines in adults, allowing for flexible use within national immunization programs and recommendations. Antibody persistence has been demonstrated up to 5 years post vaccination in all age groups. Booster doses induced robust increases in antibody titers for all four serogroups, indicative of effective priming and induction of immunological memory. The acceptable safety profile of MenACWY-CRM has been confirmed in large post-marketing safety studies.

Immunogenicity and safety of MenACWY-TT, a meningococcal conjugate vaccine, co-administered with routine childhood vaccine in healthy infants: A phase III, randomized study

BACKGROUND

Invasive meningococcal disease has a high burden in young children, particularly during infancy. We investigated the immunogenicity and safety of a quadrivalent meningococcal conjugated vaccine (MenACWY-TT) co-administered with routine vaccines in healthy infants.

METHODS

In this phase IIIb study (NCT01340898) conducted in 2 centers in Lebanon and Mexico, 750 infants were randomized (2:1:1) to receive MenACWY-TT according to 3 schedules: 3+1 (at ages 2, 4, 6 and 15-18 months; group ACWY3+1); 1+1 (at 6 and 15-18 months; group ACWY1+1) or single-dose at 15-18 months (group ACWY1). All infants received PHiD-CV and DTPa-IPV/Hib at ages 2, 4, 6, 15-18 months. Immune responses to MenACWY-TT were assessed by rSBA and hSBA at 7 months (groups ACWY3+1, ACWY1+1) and pre- and post-vaccination at 15-18 months of age (all groups). Immune responses to co-administered vaccines, reactogenicity and safety were also evaluated.

RESULTS

Immunogenicity of MenACWY-TT at 1 month post-primary vaccination was demonstrated in group ACWY3+1: the lower limit of the 95% confidence interval for the percentage of infants with rSBA titers ≥8 was >80% for each serogroup. At 7 months of age, ≥93.9% of MenACWY-TT-primed infants had rSBA titers ≥8. Post-MenACWY-TT vaccination at age 15-18 months, ≥96.3% of participants in all groups had rSBA titers ≥8, regardless of the number of doses received previously. The percentage of infants with hSBA titers ≥4 were ≥87.2% and ≥89.7% at post-primary and booster/single-dose vaccination, respectively. Immune responses to PHiD-CV and DTPa-IPV/Hib did not seem impacted by co-administration with MenACWY-TT in infancy. The incidence of all adverse events was similar among groups. Serious adverse events were reported for 63/750 children in all groups; none were considered vaccine-related by investigators.

CONCLUSION

Primary vaccination with 3 or 1 dose(s) of MenACWY-TT when co-administered with routine pediatric vaccines in infants is immunogenic and well-tolerated.

Safety and Immunogenicity of the Quadrivalent Meningococcal Serogroups A, C, W and Y Tetanus Toxoid Conjugate Vaccine Coadministered With Routine Childhood Vaccines in European Infants: An Open, Randomized Trial

BACKGROUND

This was the first study evaluating the immunogenicity and safety of the quadrivalent meningococcal tetanus toxoid conjugate vaccine (MenACWY-TT) coadministered with routine childhood vaccines in young infants.

METHODS

In this open, randomized, controlled, phase III study (NCT01144663), 2095 infants (ages 6-12 weeks) were randomized (1:1:1:1) into 4 groups to receive MenACWY-TT at 2, 3, 4 and 12 months of age, or MenACWY-TT, MenC-cross-reactive material (CRM197) or MenC-TT at 2, 4 and 12 months of age. All participants received PHiD-CV and DTPa-HBV-IPV/Hib at 2, 3, 4 and 12 months of age. Immune responses were measured by serum bactericidal activity assays using rabbit (rSBA) and human (hSBA) complement. Solicited and unsolicited symptoms were recorded during 8 and 31 days post-vaccination, respectively, and serious adverse events throughout the study.

RESULTS

Noninferiority of immune responses to MenC induced by 2 or 3 doses of MenACWY-TT versus 2 doses of MenC-TT or MenC-CRM197 was demonstrated. Predefined criteria for the immunogenicity of MenACWY-TT to MenA, MenW and MenY were met. One month after 2 or 3 primary MenACWY-TT doses, ≥93.1% and ≥88.5% of infants had rSBA and hSBA titers ≥1:8 for all serogroups. The robust increases in rSBA and hSBA titers observed for all vaccine serogroups postbooster vaccination suggested that MenACWY-TT induced immune memory. MenACWY-TT coadministered with childhood vaccines had a clinically acceptable safety profile.

CONCLUSIONS

This study supports the coadministration of MenACWY-TT with routine childhood vaccines as 2 or 3 primary doses during infancy followed by a booster dose in the second year of life.

Adverse events following quadrivalent meningococcal CRM-conjugate vaccine (Menveo®) reported to the Vaccine Adverse Event Reporting system (VAERS), 2010-2015

BACKGROUND

Limited data are available describing the post-licensure safety of meningococcal vaccines, including Menveo®. We reviewed reports of adverse events (AEs) to the Vaccine Adverse Event Reporting System (VAERS) to assess safety in all age groups.

METHODS

VAERS is a national spontaneous vaccine safety surveillance system co-administered by the Centers for Disease Control and Prevention and the US Food and Drug Administration. We searched the VAERS database for US reports of adverse events in persons who received Menveo from 1 January 2010 through 31 December 2015. We clinically reviewed reports and available medical records for serious AEs, selected pre-specified outcomes, and vaccination during pregnancy. We used empirical Bayesian data mining to identify AEs that were disproportionately reported after receipt of Menveo.

RESULTS

During the study period, VAERS received 2614 US reports after receipt of Menveo. Of these, 67 were classified as serious, including 1 report of death. Adolescents (aged 11-18years) accounted for 74% of reports. Most of the reported AEs were non-serious and described AEs consistent with data from pre-licensure studies. Anaphylaxis and syncope were the two most common events in the serious reports. We did not identify any new safety concerns after review of AEs that exceeded the data mining threshold, although we did observe disproportionate reporting for terms that were not associated with an adverse event (e.g., "incorrect drug dosage form administered", "wrong technique in drug usage process"). Although reports were limited, we did not find any evidence for concern regarding the use of Menveo during pregnancy.

CONCLUSIONS

In our review of VAERS reports, findings of AEs were consistent with the data from pre-licensure studies. Vaccine providers should continue to emphasize and adhere to proper administration of the vaccine.

Recommendations for Use of Meningococcal Conjugate Vaccines in HIV-Infected Persons - Advisory Committee on Immunization Practices, 2016

At its June 2016 meeting, the Advisory Committee on Immunization Practices (ACIP) recommended routine use of meningococcal conjugate vaccine (serogroups A, C, W, and Y; including MenACWY-D [Menactra, Sanofi Pasteur] or MenACWY-CRM [Menveo, GlaxoSmithKline]) for persons aged ≥2 months with human immunodeficiency virus (HIV) infection. ACIP has previously recommended routine vaccination of persons aged ≥2 months who have certain medical conditions that increase risk for meningococcal disease (1), including persons who have persistent (e.g., genetic) deficiencies in the complement pathway (e.g., C3, properdin, Factor D, Factor H, or C5-C9); persons receiving eculizumab (Soliris, Alexion Pharmaceuticals) for treatment of atypical hemolytic uremic syndrome or paroxysmal nocturnal hemoglobinuria (because the drug binds C5 and inhibits the terminal complement pathway); and persons with functional or anatomic asplenia (including persons with sickle cell disease). Routine vaccination with meningococcal conjugate vaccine is also recommended for all healthy adolescents in the United States (1). This report summarizes the evidence considered by ACIP in recommending vaccination for HIV-infected persons, and provides recommendations and guidance for use of meningococcal conjugate vaccines (serogroups A, C, W, and Y) among HIV-infected persons aged ≥2 months; the majority of meningococcal disease among HIV-infected persons is caused by these four serogroups.

The impact of administration of conjugate vaccines containing cross reacting material on Haemophilus influenzae type b antibody responses in infants: A systematic review and meta-analysis of randomised controlled trials

BACKGROUND

Protein-polysaccharide conjugate vaccines such as Haemophilus influenzae type b (Hib), meningococcal, and pneumococcal vaccine, induce immunological memory and longer lasting protection than plain polysaccharide vaccines. The most common proteins used as carriers are tetanus toxoid (TT) and cross reacting material-197 (CRM), a mutant form of diphtheria toxoid. CRM conjugate vaccines have been reported to suppress antibody responses to co-administered Hib-TT vaccine.

METHODS

We conducted a systematic review and meta-analysis of randomised controlled trials in which infants were randomised to receive meningococcal or pneumococcal conjugate vaccines along with Hib-TT. Trials of licensed vaccines with different carrier proteins were included for group C meningococcal (MenC), quadrivalent ACWY meningococcal (MenACWY), and pneumococcal vaccines.

RESULTS

Twenty-three trials were included in the meta-analyses. Overall, administration of MenC-CRM in a 2 or 3 dose schedule resulted in a 45% reduction in Hib antibody concentrations (GMR 0.55, 95% CI 0.49-0.62). MenACWY-CRM boosted Hib antibody responses by 22% (GMR 1.22, 95% CI 1.06-1.41) whilst pneumococcal CRM conjugate vaccines had no impact on Hib antibody responses (GMR 0.91, 95% CI 0.68-1.22).

CONCLUSIONS

The effect of CRM protein-polysaccharide conjugate vaccines on Hib antibody responses varies greatly between vaccines. Co-administration of a CRM conjugate vaccine can produce either positive or negative effects on Hib antibody responses. These inconsistencies suggest that CRM itself may not be the main driver of variability in Hib responses, and challenge current perspectives on this issue.

Persistence of the immune response after MenACWY-CRM vaccination and response to a booster dose, in adolescents, children and infants

Persistence of bactericidal antibodies following vaccination is extremely important for protection against invasive meningococcal disease, given the epidemiology and rapid progression of meningococcal infection. We present an analysis of antibody persistence and booster response to MenACWY-CRM, in adolescents, children and infants, from 7 clinical studies. Immunogenicity was assessed using the serum bactericidal assay with both human and rabbit complement. Post-vaccination hSBA titers were high, with an age- and serogroup-specific decline in titers up to 1 y and stable levels up to 5 y The waning of hSBA titers over time was more pronounced among infants and toddlers and the greatest for serogroup A. However, rSBA titers against serogroup A were consistently higher and showed little decline over time, suggesting that protection against this serogroup may be sustained. A single booster dose of MenACWY-CRM administered at 3 to 5 y induced a robust immune response in all age groups.

Immunogenicity and Safety of a 3- and 4-dose Vaccination Series of a Meningococcal ACWY Conjugate Vaccine in Infants: Results of a Phase 3b, Randomized, Open-label Trial

BACKGROUND

The quadrivalent meningococcal glycoconjugate vaccine MenACWY-CRM is licensed for children from 2 months of age as a 4-dose series. This study assessed the immunogenicity of a 3-dose MenACWY-CRM vaccination series in infants, compared with the 4-dose series, and evaluated the impact of MenACWY-CRM concomitant administration on immune responses to the 13-valent pneumococcal conjugate vaccine (PCV13).

METHODS

Overall, 751 healthy infants (age: 55-89 days) were randomized to receive 3 or 4 doses of MenACWY-CRM (2/4/12 or 2/4/6/12 months of age, respectively) with PCV13 + routine vaccinations (ACWY3 and ACWY4 groups, respectively) or PCV13 + routine vaccinations only (routine group). Immunological noninferiority of the 3-dose versus 4-dose MenACWY-CRM vaccination series was evaluated at 13 months of age for serogroups CWY; noninferiority of immune responses to PCV13 serotypes for concomitant administration of MenACWY-CRM and PCV13 was evaluated at 7 and 13 months of age.

RESULTS

At 13 months, 88%-100% of subjects in groups ACWY3 and ACWY4 achieved seroprotective bactericidal antibody titers against serogroups ACWY; noninferiority criteria for the 3-dose versus 4-dose MenACWY-CRM vaccination series were met. At 7 months, noninferiority criteria were met for all PCV13 serotypes except for serotypes 3 and 5 (group ACWY3) and 19A (group ACWY4). At 13 months, noninferiority criteria were met for all PCV13 serotypes for both ACWY groups.

CONCLUSIONS

After completion of either MenACWY-CRM vaccination series, most subjects achieved seroprotective titers against serogroups ACWY, with the 3-dose series being noninferior to the 4-dose series for serogroups CWY, and no interference with immune responses against PCV13 serotypes was observed (NCT01214837).

Safety and Immunogenicity of a Quadrivalent Meningococcal Conjugate Vaccine and Commonly Administered Vaccines After Coadministration

BACKGROUND

Given the broad age range across which the quadrivalent meningococcal conjugate vaccine MenACWY-CRM is used, coadministration with routine vaccines should be evaluated across age groups for possible immunologic interference and impact on vaccine reactogenicity and safety.

METHODS

We summarize data from a large population of infants, adolescents and international travelers from 10 phase 3 or 4 clinical studies to evaluate coadministration of MenACWY-CRM with commonly administered vaccines. Noninferiority analyses of immune responses were performed across studies and age groups for each vaccine. Reactogenicity and safety were also assessed.

RESULTS

In infants, MenACWY-CRM coadministered with routine vaccines did not reduce immune responses to diphtheria, tetanus, poliovirus, hepatitis B, Haemophilus influenzae type b, pneumococcal conjugate, measles-mumps-rubella, varicella or pertussis antigens. Noninferiority criteria were not met for some pneumococcal conjugate serotypes at 7 months of age, but no consistent trends were observed. In adolescents, coadministration did not reduce immune responses to tetanus, diphtheria and human papilloma virus vaccine antigens. Noninferiority criteria for pertussis antigens were not uniformly met in infant and adolescent studies, although the clinical relevance is unclear. In adults, coadministration did not reduce immune responses to hepatitis A/B, typhoid fever, yellow fever, Japanese encephalitis and rabies antigens. Immune responses to MenACWY-CRM were not impacted by coadministration of commonly administered vaccines. Coadministration did not increase frequencies of postvaccination adverse events in any age group.

CONCLUSIONS

With no clinically relevant vaccine interactions or impact on vaccine reactogenicity or safety, these results support the coadministration of MenACWY-CRM with routine vaccines in all age groups.

Safety and immunogenicity of meningococcal ACWY CRM197-conjugate vaccine in children, adolescents and adults in Russia

Neisseria meningitidis is the leading cause of bacterial invasive infections in people aged <15 years in the Russian Federation. The aim of this phase III, multicenter, open-label study was to assess the immunogenicity and safety of the quadrivalent meningococcal CRM197-conjugate vaccine MenACWY when administered to healthy Russian subjects aged 2 years and above. A total of 197 subjects were immunized with a single dose of the vaccine, and serogroup-specific serum bactericidal activity was measured pre and 1-month post-vaccination with human complement (hSBA) serum titers. Regardless of baseline serostatus, 1 month after a single dose of MenACWY-CRM197 85% (95%CI, 79-90%) of subjects showed serologic response against serogroup A, 74% (67-80%) against serogroup C, 60% (53-67%) against serogroup W, and 83% (77-88%) against serogroup Y. The percentage of subjects with hSBA titers ≥ 1:8 1 month after vaccination was 89% (83-93%) against serogroup A, 84% (78-89%) against serogroup C, 97% (93-99%) against serogroup W, and 88% (82-92%) against serogroup Y. Comparable results were obtained across all subjects: children (2 to 10 years), adolescents (11 to 17 years), and adults (≥18 years). The MenACWY-CRM197 vaccine showed an acceptable safety profile and was well tolerated across all age groups, with no serious adverse events or deaths reported during the study. In conclusion, a single dose of meningococcal MenACWY-CRM197 vaccine is immunogenic and has an acceptable safety profile, provides a broad protection against the most frequent epidemic serogroups, and is a suitable alternative to currently available unconjugated monovalent or bivalent polysaccharide vaccines in Russia.

Safety and immunogenicity of an investigational meningococcal ACWY conjugate vaccine (MenACWY-CRM) in healthy Indian subjects aged 2 to 75 years

BACKGROUND

This phase 3, multi-center, open-label study evaluated the immunogenicity and safety of a quadrivalent meningococcal conjugate vaccine (MenACWY-CRM, Menveo(®); Novartis Vaccines and Diagnostics S.r.l., Siena, Italy) in healthy Indian subjects aged 2-75 years, to provide data for licensure in India.

METHODS

A total of 180 subjects were enrolled (60 subjects 2-10 years, 60 subjects 11-18 years, and 60 subjects 19-75 years) and received one dose of MenACWY-CRM. Serum bactericidal activity with human complement (hSBA) was measured before and 1 month after vaccination. Adverse events were collected throughout the 29-day study period.

RESULTS

Percentages of subjects with post-vaccination hSBA ≥8 were 72%, 95%, 94%, and 90% for serogroups A, C, W, and Y, respectively. Geometric mean titers rose 7-fold to 42-fold against the four serogroups. Similar immune responses were observed for the age subgroups 2-10 years, 11-18 years, and 19-75 years. Seroresponse rates at 1 month following vaccination were 72%, 88%, 55%, and 71% for serogroups A, C, W, and Y, respectively. The vaccine was well tolerated with no safety concerns.

CONCLUSION

A single dose of MenACWY-CRM induced a robust immune response against all four meningococcal serogroups and was well tolerated in an Indian population 2-75 years of age.

A comparative evaluation of two investigational meningococcal ABCWY vaccine formulations: Results of a phase 2 randomized, controlled trial

BACKGROUND

A meningococcal vaccine protective against all major disease-associated serogroups (A, B, C, W and Y) is an unmet public health need. In this phase 2 observer-blinded, randomized, controlled study, two investigational meningococcal ABCWY vaccine formulations were evaluated to assess their immunological noninferiority to a licensed quadrivalent meningococcal ACWY glycoconjugate vaccine (MenACWY-CRM) for serogroups ACWY and immunogenicity against serogroup B test strains, as well as for formulation selection based on a desirability index (DI). Each investigational MenABCWY formulation contained recombinant protein and outer membrane vesicle (OMV) components of a licensed serogroup B vaccine (4CMenB) combined with components of MenACWY-CRM.

METHODS

A total of 484 healthy 10-25 year-old participants were randomized to receive two doses, two months apart, of an investigational MenABCWY formulation that contained either a full or one-quarter dose of OMV, 4CMenB alone, or a Placebo followed by MenACWY-CRM. Immunogenicity against each of serogroups ACWY and four serogroup B test strains was assessed by serum bactericidal assay with human complement (hSBA). MenABCWY formulations were compared by a DI based on key immunogenicity and reactogenicity parameters.

RESULTS

Seroresponse rates for serogroups ACWY were significantly higher after two doses of either MenABCWY formulation than after one dose of MenACWY-CRM: respectively, A: 90-92% vs. 73%; C: 93-95% vs. 63%; W: 80-84% vs. 65%; and Y: 90-92% vs. 75%. Prespecified noninferiority criteria were met. Both MenABCWY formulations induced substantial immune responses against serogroup B test strains, although 4CMenB responses were higher. Overall DIs for both MenABCWY formulations were similar. Reactogenicity profiles of the MenABCWY formulations were similar to each other and to that of 4CMenB. No vaccine-related serious adverse events were reported.

CONCLUSIONS

Both investigational MenABCWY formulations elicited robust immune responses against serogroups ACWY and serogroup B test strains, and had acceptable reactogenicity profiles, with no safety concerns identified.

Immunogenicity and safety of concomitant administration of a combined hepatitis A/B vaccine and a quadrivalent meningococcal conjugate vaccine in healthy adults

BACKGROUND

This phase 3b randomized, open-label study evaluated the immunogenicity and safety of coadministration of a hepatitis A and/or B vaccine with a quadrivalent oligosaccharide meningococcal CRM197 -conjugate vaccine (MenACWY-CRM), in the context of an accelerated hepatitis A and/or B immunization schedule.

METHODS

A total of 252 healthy adult subjects were randomized to three groups to receive hepatitis A/B only (HepA/B), hepatitis A/B coadministered with MenACWY-CRM (HepA/B+MenACWY-CRM), or MenACWY-CRM only (MenACWY-CRM). Hepatitis A and/or B vaccination was administered in the form of a single booster dose or a primary three-dose series, depending on the hepatitis A and/or B vaccination history of subjects. Antibody responses to hepatitis A/B vaccination were assessed 1 month following the last hepatitis A and/or B dose. Serum bactericidal activity with human complement (hSBA) against meningococcal serogroups A, C, W-135, and Y was assessed 1 month post-MenACWY-CRM vaccination. Safety was monitored throughout the study.

RESULTS

At 1 month following the final hepatitis A and/or B vaccination, concomitant administration of hepatitis A/B and MenACWY-CRM was non-inferior to administration of hepatitis A/B alone in terms of geometric mean concentrations of antibodies against the hepatitis A and B antigens. One month post-MenACWY-CRM vaccination, the percentages of subjects achieving hSBA titers ≥8 for serogroups A, C, W-135, and Y in the HepA/B+MenACWY-CRM group (76, 87, 99, and 94%, respectively) were comparable to those in the MenACWY-CRM group (67, 82, 96, and 88%, respectively). The percentages of subjects reporting adverse events (AEs) were similar across study groups and a majority of the reported AEs were mild to moderate in nature. There were no study vaccine-related serious AEs.

CONCLUSIONS

MenACWY-CRM can be administered concomitantly with a hepatitis A and/or B vaccine in the context of an accelerated hepatitis A and/or B immunization schedule without increasing safety concerns or compromising the immune responses to any of the vaccine antigens. [NCT01453348].

Safety and immunogenicity of typhoid fever and yellow fever vaccines when administered concomitantly with quadrivalent meningococcal ACWY glycoconjugate vaccine in healthy adults

BACKGROUND

Compact and short pre-travel immunization schedules, which include several vaccinations in a single visit, are desirable for many travelers. However, concomitant vaccination could potentially compromise immunogenicity and/or safety of the individual vaccines and, therefore, possible vaccine interferences should be carefully assessed. This article discusses the immunogenicity and safety of travel vaccines for typhoid fever (TF) and yellow fever (YF), when administered with or without a quadrivalent meningococcal glycoconjugate ACWY-CRM vaccine (MenACWY-CRM).

METHODS

Healthy adults (18-≤60 years) were randomized to one of three vaccine regimens: TF + YF + MenACWY-CRM (group I; n = 100), TF + YF (group II; n = 101), or MenACWY-CRM (group III; n = 100). Immunogenicity at baseline and 4 weeks post-vaccination (day 29) was assessed by serum bactericidal assay using human complement (hSBA), enzyme-linked immunosorbent assay (ELISA), or a neutralization test. Adverse events (AEs) and serious adverse events (SAEs) were collected throughout the study period.

RESULTS

Non-inferiority of post-vaccination geometric mean concentrations (GMCs) and geometric mean titers (GMTs) was established for TF and YF vaccines, respectively, when given concomitantly with MenACWY-CRM vaccine versus when given alone. The percentages of subjects with seroprotective neutralizing titers against YF on day 29 were similar in groups I and II. The antibody responses to meningococcal serogroups A, C, W-135, and Y were within the same range when MenACWY-CRM was given separately or together with TF and YF vaccines. The percentage of subjects reporting AEs was the same for TF and YF vaccines with or without MenACWY-CRM vaccine. There were no reports of SAEs or AEs leading to study withdrawals.

CONCLUSIONS

These data provide evidence that MenACWY-CRM can be administered with typhoid Vi polysaccharide vaccine and live attenuated YF vaccine without compromising antibody responses stimulated by the individual vaccines. MenACWY-CRM can, therefore, be incorporated into travelers' vaccination programs without necessitating an additional clinic visit (NCT01466387).

Licensed pertussis vaccines in the United States. History and current state

The United States switched from whole cell to acellular pertussis vaccines in the 1990s following global concerns with the safety of the whole cell vaccines. Despite high levels of acellular pertussis vaccine coverage, the United States and other countries are experiencing large pertussis outbreaks. The aim of this article is to describe the historical context which led to acellular pertussis vaccine development, focusing on vaccines currently licensed in the US, and to review evidence that waning protection following licensed acellular pertussis vaccines have been significant factors in the widespread reappearance of pertussis.

Antibody persistence after primary and booster doses of a quadrivalent meningococcal conjugate vaccine in adolescents

BACKGROUND

The aim of this study was to evaluate antibody persistence 5 years after primary vaccination with the quadrivalent meningococcal conjugate vaccines MenACWY-CRM or MenACWY-D and 2 years after a booster dose of MenACWY-CRM, in the context of a phase 3 study.

METHODS

Subjects (aged 19.2 ± 2.3 years) were assigned to 5 groups according to whether they had previously received primary vaccination (at 14.2 ± 2.2 years) with MenACWY-CRM (N = 131) or MenACWY-D (N = 76), a booster dose of MenACWY-CRM 3 years after primary vaccination with MenACWY-CRM (N = 44) or MenACWY-D (N = 31) or no vaccination (N = 107). The immunogenicity measures were percentages of subjects with serum bactericidal activity (hSBA) ≥ 1:8 for serogroups A, C, W and Y and hSBA geometric mean titers. Comparisons with age-matched, vaccine-naive subjects were performed.

RESULTS

A majority of subjects vaccinated 5 years previously maintained hSBA ≥ 1:8 against serogroups C, W and Y in the MenACWY-CRM (59%-82%) and MenACWY-D groups (54%-73%); this was lower for serogroup A in both groups. There was a decline in antibody titers after primary vaccination, especially in the first 2 years postprimary vaccination, with steady concentrations during the next 3 years. Two years after MenACWY-CRM booster vaccination the percentages of subjects with hSBA ≥ 1:8 ranged from 77% to 100% across serogroups and geometric mean titers were 2.5- to 8-fold higher than prebooster values across serogroups.

CONCLUSIONS

Booster vaccination with MenACWY-CRM elicited a robust immune response during the 2-year follow-up period, irrespective of previous vaccination.

Preparing children for international travel: need for training and pediatric-focused research

BACKGROUND

The International Society of Travel Medicine (ISTM) Pediatric Interest Group (PedIG) was created in 2010. We studied the group's professional characteristics and practice patterns to identify clinical areas requiring further training and research related to pediatric international travel.

METHODS

PedIG members were emailed a two-part online questionnaire in September 2011, which comprised questions about professional and practice details, followed by a survey regarding decisions on nine patient scenarios that represent common pediatric pre-travel health challenges.

RESULTS

Ninety-three (34%) of 273 members completed the survey. Most were physicians (80%) having a primary specialization in pediatrics (55%) and family medicine (19%). About a third (37%) had acquired the ISTM Certificate in Travel Health (CTH); 14 and 11% chose not to provide malaria chemoprophylaxis for a 2-month-old infant and a 13-year-old child traveling to West Africa, respectively. Azithromycin for empiric treatment of travelers' diarrhea in a 2-year-old traveler to Thailand and Mexico was suggested by 74 and 58%, respectively, while the use of acetazolamide for a 2-month old infant traveling to a high-altitude destination was rarely (13%) chosen. In vaccine-focused scenarios, 71, 69, 21, and 10% would prescribe the meningococcal vaccine for a 6-month-old traveler to Burkina Faso, Japanese encephalitis vaccine to a 10-year-old traveler to Cambodia, hepatitis A vaccine to a 6-month-old traveler to El Salvador, and the typhoid vaccine to a 1-year-old traveler to India, respectively.

CONCLUSIONS

Members of the PedIG have diverse professional and practice backgrounds. Lack of awareness of established guidelines may place international pediatric travelers at risk for travel-associated morbidity. Strategies are needed to facilitate education and support research in pediatric travel medicine to formulate evidence-based guidelines wherever they are currently missing.

Safety of vaccines used for routine immunization of U.S. children: a systematic review

BACKGROUND

Concerns about vaccine safety have led some parents to decline recommended vaccination of their children, leading to the resurgence of diseases. Reassurance of vaccine safety remains critical for population health. This study systematically reviewed the literature on the safety of routine vaccines recommended for children in the United States.

METHODS

Data sources included PubMed, Advisory Committee on Immunization Practices statements, package inserts, existing reviews, manufacturer information packets, and the 2011 Institute of Medicine consensus report on vaccine safety. We augmented the Institute of Medicine report with more recent studies and increased the scope to include more vaccines. Only studies that used active surveillance and had a control mechanism were included. Formulations not used in the United States were excluded. Adverse events and patient and vaccine characteristics were abstracted. Adverse event collection and reporting was evaluated by using the McHarm scale. We were unable to pool results. Strength of evidence was rated as high, moderate, low, or insufficient.

RESULTS

Of 20 478 titles identified, 67 were included. Strength of evidence was high for measles/mumps/rubella (MMR) vaccine and febrile seizures; the varicella vaccine was associated with complications in immunodeficient individuals. There is strong evidence that MMR vaccine is not associated with autism. There is moderate evidence that rotavirus vaccines are associated with intussusception. Limitations of the study include that the majority of studies did not investigate or identify risk factors for AEs; and the severity of AEs was inconsistently reported.

CONCLUSIONS

We found evidence that some vaccines are associated with serious AEs; however, these events are extremely rare and must be weighed against the protective benefits that vaccines provide.

Immunogenicity and safety of a quadrivalent meningococcal polysaccharide CRM conjugate vaccine in infants and toddlers

OBJECTIVES

This phase III study assessed the safety and immunogenicity of MenACWY-CRM, a quadrivalent meningococcal conjugate vaccine, administered with routine vaccines starting at 2 months of age.

METHODS

Healthy infants received MenACWY-CRM in a two- or three-dose primary infant series plus a single toddler dose. In addition, a two-dose toddler catch-up series was evaluated. Immune responses to MenACWY-CRM were assessed for serum bactericidal activity with human complement (hSBA). Reactogenicity and safety results were collected systematically.

RESULTS

After a full infant/toddler series or two-dose toddler catch-up series, MenACWY-CRM elicited immune responses against the four serogroups in 94-100% of subjects. Noninferiority of the two- versus three-dose MenACWY-CRM infant dosing regimen was established for geometric mean titers for all serogroups. Following the three-dose infant primary series, 89-98% of subjects achieved an hSBA ≥ 8 across all serogroups. Immune responses to concomitant routine vaccines given with MenACWY-CRM were noninferior to responses to routine vaccines alone, except for pertactin after the two-dose infant series. Noninferiority criteria were met for all concomitant antigens after the three-dose infant series.

CONCLUSIONS

MenACWY-CRM vaccination regimens in infants and toddlers were immunogenic and well tolerated. No clinically meaningful effects of concomitant administration with routine infant and toddler vaccines were observed.

Co-administration of a meningococcal glycoconjugate ACWY vaccine with travel vaccines: a randomized, open-label, multi-center study

BACKGROUND

Potential interactions between vaccines may compromise the immunogenicity and/or safety of individual vaccines so must be assessed before concomitant administration is recommended. In this study, the immunogenicity and safety of travel vaccines against Japanese encephalitis (JEV) and rabies (PCECV) administered together with or without a quadrivalent meningococcal glycoconjugate ACWY-CRM vaccine were evaluated (NCT01466387).

METHOD

Healthy adults aged 18 to ≤60 years were randomized to one of four vaccine regimens: JEV + PCECV + MenACWY-CRM, JEV + PCECV, PCECV or MenACWY-CRM. Immunogenicity at baseline and 28 days post-complete vaccination was assessed by serum bactericidal assay using human complement or neutralization tests. Adverse events (AEs) were collected throughout the study period.

RESULTS

JEV + PCECV + MenACWY-CRM was non-inferior to JEV + PCECV. Post-vaccination seroprotective neutralizing titers or concentrations were achieved in 98-99% (JE) and 100% (rabies) of subjects across the vaccine groups. Antibody responses to vaccine meningococcal serogroups were in the same range for MenACWY-CRM and JEV + PCECV + MenACWY-CRM. Rates of reporting of AEs were similar for JEV + PCECV and JEV + PCECV + MenACWY-CRM.

CONCLUSIONS

MenACWY-CRM was administered with an inactivated adjuvanted JE and a purified chick embryo cell-culture rabies vaccine without compromising immunogenicity or safety of the individual vaccines. These data provide evidence that MenACWY-CRM could be effectively incorporated into travel vaccination programs.

TRIAL NUMBER

NCT01466387.

Safety of a quadrivalent meningococcal serogroups A, C, W and Y conjugate vaccine (MenACWY-CRM) administered with routine infant vaccinations: results of an open-label, randomized, phase 3b controlled study in healthy infants

BACKGROUND

The highest risk for invasive meningococcal disease (IMD) is in infants aged <1 year. Quadrivalent meningococcal conjugate vaccination has the potential to prevent IMD caused by serogroups A, C, W and Y. This phase 3b, multinational, open-label, randomized, parallel-group, multicenter study evaluated the safety of a 4-dose series of MenACWY-CRM, a quadrivalent meningococcal conjugate vaccine, concomitantly administered with routine vaccinations to healthy infants.

METHODS

Two-month-old infants were randomized 3:1 to receive MenACWY-CRM with routine vaccines or routine vaccines alone at ages 2, 4, 6 and 12 months. Adverse events (AEs) that were medically attended and serious adverse events (SAEs) were collected from all subjects from enrollment through 18 months of age. In a subset, detailed safety data (local and systemic solicited reactions and all AEs) were collected for 7 days post vaccination. The primary objective was a non-inferiority comparison of the percentages of subjects with ≥1 severe systemic reaction during Days 1-7 after any vaccination of MenACWY-CRM plus routine vaccinations versus routine vaccinations alone (criterion: upper limit of 95% confidence interval [CI] of group difference <6%).

RESULTS

A total of 7744 subjects were randomized with 1898 in the detailed safety arm. The percentage of subjects with severe systemic reactions was 16% after MenACWY-CRM plus routine vaccines and 13% after routine vaccines alone (group difference 3.0% (95% CI -0.8, 6.4%). Although the non-inferiority criterion was not met, post hoc analysis controlling for significant center and group-by-center differences revealed that MenACWY-CRM plus routine vaccinations was non-inferior to routine vaccinations alone (group difference -0.1% [95% CI -4.9%, 4.7%]). Rates of solicited AEs, medically attended AEs, and SAEs were similar across groups.

CONCLUSION

In a large multinational safety study, a 4-dose series of MenACWY-CRM concomitantly administered with routine vaccines was clinically acceptable with a similar safety profile to routine vaccines given alone.

Immunogenicity and safety of a CRM-conjugated meningococcal ACWY vaccine administered concomitantly with routine vaccines starting at 2 months of age

BACKGROUND

Infants are at the highest risk for meningococcal disease and a broadly protective and safe vaccine is an unmet need in this youngest population. We evaluated the immunogenicity and safety of a 4-dose infant/toddler regimen of MenACWY-CRM given at 2, 4, 6, and 12 months of age concomitantly with pentavalent diphtheria-tetanus-acellular pertussis-Hemophilus influenzae type b-inactivated poliovirus-combination vaccine (DTaP-IPV/Hib), hepatitis B vaccine (HBV), 7- or 13-valent conjugate pneumococcal vaccine (PCV), and measles, mumps, and rubella vaccine (MMR).

RESULTS

Four doses of MenACWY-CRM induced hSBA titers ≥8 in 89%, 95%, 97%, and 96% of participants against serogroups A, C, W-135, and Y, respectively. hSBA titers ≥8 were present in 76-98% of participants after the first 3 doses. A categorical linear analysis incorporating vaccine group and study center showed responses to routine vaccines administered with MenACWY-CRM were non-inferior to routine vaccines alone, except for seroresponse to the pertussis antigen fimbriae. The reactogenicity profile was not affected when MenACWY-CRM was administered concomitantly with routine vaccines.

CONCLUSION

MenACWY-CRM administered with routine concomitant vaccinations in young infants was well tolerated and induced highly immunogenic responses against each of the serogroups without significant interference with the immune responses to routine infant vaccinations.

METHODS

Healthy 2 month old infants were randomized to receive MenACWY-CRM with routine vaccines (n = 258) or routine vaccines alone (n = 271). Immunogenicity was assessed by serum bactericidal assay using human complement (hSBA). Medically attended adverse events (AEs), serious AEs (SAEs) and AEs leading to study withdrawal were collected throughout the study period.

Protein carriers of conjugate vaccines: characteristics, development, and clinical trials

The immunogenicity of polysaccharides as human vaccines was enhanced by coupling to protein carriers. Conjugation transformed the T cell-independent polysaccharide vaccines of the past to T cell-dependent antigenic vaccines that were much more immunogenic and launched a renaissance in vaccinology. This review discusses the conjugate vaccines for prevention of infections caused by Hemophilus influenzae type b, Streptococcus pneumoniae, and Neisseria meningitidis. Specifically, the characteristics of the proteins used in the construction of the vaccines including CRM, tetanus toxoid, diphtheria toxoid, Neisseria meningitidis outer membrane complex, and Hemophilus influenzae protein D are discussed. The studies that established differences among and key features of conjugate vaccines including immunologic memory induction, reduction of nasopharyngeal colonization and herd immunity, and antibody avidity and avidity maturation are presented. Studies of dose, schedule, response to boosters, of single protein carriers with single and multiple polysaccharides, of multiple protein carriers with multiple polysaccharides and conjugate vaccines administered concurrently with other vaccines are discussed along with undesirable consequences of conjugate vaccines. The clear benefits of conjugate vaccines in improving the protective responses of the immature immune systems of young infants and the senescent immune systems of the elderly have been made clear and opened the way to development of additional vaccines using this technology for future vaccine products.

Prevention of meningococcal infections in the first 2 years of life

The spectrum of disease caused by Neisseria meningitidis includes bacteremia, fulminant sepsis (meningococcemia), meningitis, and pneumonia. The incidence of meningococcal infection has long been higher in infancy than adolescents or adults older than 65 years (a third group with an increased risk based on age). Five meningococcal serogroups (A, B, C, Y, and W135) cause the great majority of human disease. Serogroup B strains cause about two-thirds of disease in children younger than 6 years. For this reason, new meningococcal vaccine formulations have been developed and evaluated in children younger than 2 years. Of four meningococcal vaccines currently licensed in the United States, two conjugate products, (MenACWY-D [Menactra], Sanofi Pasteur; HibMenCY-TT [MenHibrix], GlaxoSmithKline), are recommended for infants and toddlers younger than 2 years who have an increased risk for invasive meningococcal disease. High-risk conditions are complement deficiencies, community outbreaks, functional or anatomic asplenia, and travel to high-risk areas in which serogroup A infection is prevalent. Recommendations vary by age, dosing, and indication between these two products. Both licensed products are immunogenic and have side-effect profiles that are considered safe for use. In most cases, concomitant use with other recommended childhood vaccines does not interfere with responses to these vaccines. As of yet, there has not been universal adoption of this immunization in the infant population by parents or providers. Factors that weigh against the implementation of a national routine infant program include the prevention of only 40 to 50 meningococcal cases, two to four deaths per year, and a relatively low case fatality among infants. Some argue that costs should not be considered a barrier because infant deaths and morbidity would be prevented. The availability of a serogroup B vaccine would improve impact and cost-effectiveness of a routine infant meningococcal vaccine program. Debate over the implementation of routine infant meningococcal vaccination in the United States is ongoing. This review focuses on vaccines for the prevention of N. meningitidis infection in infants and young toddlers in the first 2 years of life.

A Licensed Combined Haemophilus influenzae Type b-Serogroups C and Y Meningococcal Conjugate Vaccine

The highest incidence of meningococcal disease occurs in infants younger than 1 year of age. However, in the US, prior to June 2012, there was no meningococcal vaccine licensed for use in this age group. In the US, where both serogroups C and Y contribute substantially to the overall epidemiology of invasive meningococcal disease, a vaccine combining these capsular polysaccharides was developed. We review the newly licensed HibMenCY-TT (MenHibrix™, GlaxoSmithKline Biologicals, Rixensart, Belgium), a novel vaccine containing Haemophilus influenzae type b (Hib) and serogroups C and Y Neisseria meningitidis conjugated to tetanus toxoid. We describe the vaccine, summarize the clinical trial data, and describe the patient populations recommended to receive HibMenCY-TT as their primary vaccination against Hib. Phase II and III clinical trials found HibMenCY-TT to be well tolerated, safe, and immunogenic when administered at 2, 4, 6, and 12-15 months of age for primary vaccination against both Hib and serogroups C and Y meningococcal disease. In October 2012, the Advisory Committee on Immunisation Practice in the US recommended HibMenCY-TT vaccination for infants at increased risk of meningococcal disease. HibMenCY-TT may be given concomitantly with other routine infant vaccines. It induces antibodies against Hib as well as bactericidal activity against meningococcal serogroup C and Y without increasing the number of injections required. As meningococcal disease epidemiology is dynamic, global surveillance remains essential. In the future, other countries may also benefit from the addition of HibMenCY-TT into their vaccine armamentarium against meningococcal disease.

Kaiser Permanente Vaccine Study Center: Highlights of 2009-2012

The Kaiser Permanente Vaccine Study Center is a specialized research organization in Oakland, California. They have been an active vaccine research group for many years, and have participated in and led a multitude of vaccine studies. This article will review the last three years of research activities.

Update on child and adolescent immunizations: selected review of US recommendations and literature

PURPOSE OF REVIEW

To provide a clinically relevant synopsis of recent research findings as well as updated guidelines from the American Academy of Pediatrics and Advisory Committee on Immunization Practices regarding child and adolescent immunizations.

RECENT FINDINGS

Childhood vaccinations have served to dramatically reduce pediatric morbidity and mortality in the USA. Much of the recent research has focused on the improvement of current vaccines as well as on the development of new vaccines. By improving the safety, efficacy and immunogenicity of vaccinations, children can be more fully protected. Additionally, recommendations have broadened as vaccinations have been proven well tolerated and effective for a growing number of subpopulations. Although more groups of children are now included in vaccination recommendations, efforts must continue to ensure that all eligible children receive their vaccinations. This article reviews selected recent publications on influenza, human papillomavirus, the childhood and adolescent/adult formulations of diphtheria and tetanus toxoids and acellular pertussis, meningococcal conjugate and pneumococcal vaccines. The relationship between febrile seizures and childhood immunizations is explored.

SUMMARY

The research on childhood and adolescent vaccinations is continuously growing and will serve to shape future recommendations. Through their findings, we can learn how to optimize the protection of all children and adolescents against these very serious diseases.