Safety and Immunogenicity of Two Formulations of a Hexavalent Diphtheria-Tetanus-Acellular Pertussis-Inactivated Poliovirus-Haemophilus influenzaeb Conjugate-Hepatitis B Vaccine in 15 to 18 Month-Old Children

DTaP5-HBV-IPV-Hib pediatric hexavalent combination vaccine for use in children from 6 weeks through to 4 years of age

Introduction: Combination vaccines reduce the number of injections received by children, hence improving timeliness and coverage, and general acceptability among caregivers and health-care providers. The most recent hexavalent vaccine, DTaP5-HBV-IPV-Hib, has been also approved by the FDA.Areas covered: DTaP5-HBV-IPV-Hib has demonstrated good immunogenic and safety profiles, not inferior to other hexavalent vaccines already in use in the European market. Either (2p+1/3p+1) immunization schedules can be used with no significant differences. A low incidence of severe adverse events has been shown, similar to other combination vaccines. No issues have arisen when concomitantly administered with other vaccines.Expert opinion: The inclusion of two additional acellular pertussis components (FIM2 and FIM3) might yield better protection against the disease, but this remains to be clinically proven. The new vaccine uses Hib with unique protein carrier (PRP-OMPC) which elicits higher earlier immune response without compromising safety. Compliance with the immunization schedules is expected to increase by decreasing the number of injections needed in combined vaccines for a single visit. In addition, the improvements on the ease-of-use by its liquid-formulation, makes the vaccine preparation more acceptable for use in clinics and may reduce the odds of administration errors.

Immunogenicity and safety of a new hexavalent vaccine (DTaP5-IPV-HB-Hib) administered in a mixed primary series schedule with a pentavalent vaccine (DTaP5-IPV-Hib)

DTaP5-IPV-HB-Hib vaccine is a fully-liquid, combination hexavalent vaccine. This phase III, open-label, multicentre study conducted in Spain, evaluated the immune response to all DTaP5-IPV-HB-Hib antigens when the vaccine was used in a mixed hexa/penta/hexa primary series. Infants (who had received one dose of hepatitis B vaccine at birth) received a mixed schedule including DTaP5-IPV-HB-Hib (PRP-OMP conjugate) at 2 and 6months of age, DTaP5-IPV-Hib at 4months, meningococcal serogroup C conjugate (MCC) vaccine at 2 and 4months, and routine rotavirus and pneumococcal vaccination. One month post-dose 3 of the mixed schedule, response rates were considered acceptable if the lower bound of the two-sided 95% confidence interval around the post-vaccination response rate was >90% for hepatitis B and >80% for Haemophilus influenzae type b (Hib). Secondary immunogenicity objectives included description of the antibody response to all hexavalent antigens one month after completion of the mixed schedule, and to MCC antigen one month after the second MCC dose. The safety profile after each dose of study vaccine was described. Of 385 healthy infants enrolled, 384 completed the study. The primary objective was achieved for both hepatitis B and Hib; the lower bound of the 2-sided 95% CI of the response rates (97.2% and 99.0%, respectively) were greater than the pre-specified acceptability thresholds. One month post-dose 3 of the mixed schedule, all participants were seroprotected against diphtheria, tetanus and polio. The mixed schedule induced a robust immune response to all hexavalent antigens. The co-administration of the hexavalent vaccine in a mixed schedule with MCC vaccine did not reduce the immune response to vaccine antigens. Vaccines were well tolerated. In conclusion, the acceptability of response rates against Hib and hepatitis B were demonstrated one month post-dose 3 of the mixed schedule; robust immune responses against all other hexavalent antigens were observed. clinicaltrial.gov: NCT01839188; EudraCT: 2012-004221-25.

DTaP5-HB-IPV-Hib Vaccine (Vaxelis®): A Review of its Use in Primary and Booster Vaccination

Vaxelis^® is a fully liquid, ready-to-use, hexavalent vaccine approved in the EU for primary and booster vaccination in infants and toddlers from the age of 6 weeks against diphtheria, tetanus, pertussis, hepatitis B, poliomyelitis, and invasive diseases caused by Haemophilus influenzae type b (Hib). It contains diphtheria and tetanus toxoids, five acellular pertussis antigens, recombinant hepatitis B virus surface antigen produced in the yeast, Saccharomyces cerevisiae, inactivated poliovirus, and the Hib polysaccharide (polyribosylribitol phosphate) conjugated to the outer membrane protein complex of Neisseria meningitidis. In pivotal clinical studies, Vaxelis^® was highly immunogenic for all its component toxoids/antigens when administered by three different schedules. Primary endpoints of seroprotection or vaccine response rates with Vaxelis^® met the predefined acceptability criteria and were noninferior to those with comparator vaccines (Infanrix^® hexa or Pentacel^® plus Recombivax HB^®). Limited data indicate that immune responses to Vaxelis^® in preterm infants were generally similar to those seen in the overall population. Vaxelis^® can be coadministered with a number of common childhood vaccines. In clinical studies, Vaxelis^® was generally well tolerated with a tolerability profile similar to that of the comparator vaccines. Available clinical data indicate that Vaxelis^® is a new hexavalent vaccine option for immunization against several serious childhood infectious diseases.

DTaP5-IPV-Hib-HepB, a hexavalent vaccine for infants and toddlers

INTRODUCTION

Combination vaccines reduce the 'shot burden' and simplify the childhood immunization schedule. Only 5-valent DTaP-based vaccines are licensed in the U.S. Areas covered: A new combination vaccine - DTaP5-IPV-Hib-HepB - is described, which induces antibody responses in infants (given in different schedules, including a 2, 4, and 6-month schedule) that are similar to the respective component vaccines. The vaccine appears to be safe and would be expected to protect against six diseases: diphtheria, tetanus, pertussis, hepatitis B, H influenzae type b, and polio. Administration is associated with higher rates of mild fever, but without significant safety signals. Expert commentary: Incorporation of this hexavalent vaccine into the U.S. schedule could improve coverage rates and timeliness, and addition to the E.U. market would add depth to the available repertoire of combination vaccines.

Safety and immunogenicity of a toddler dose following an infant series of a hexavalent diphtheria, tetanus, acellular pertussis, inactivated poliovirus, Haemophilus influenzae type b, hepatitis B vaccine administered concurrently or at separate visits with a heptavalent pneumococcal conjugate vaccine

BACKGROUND

Combination diphtheria-tetanus-5 component acellular pertussis-inactivated poliovirus-Haemophilus influenzae b conjugate-hepatitis B vaccine (DTaP5-IPV-Hib-HepB) administered either concurrently with 7-valent pneumococcal conjugate vaccine (PCV7) or 1 month apart was generally safe and immunogenic at 2, 4 and 6 months of age. This study examined the effects of a booster dose at age 15 months.

METHODS

Participants were randomized to DTaP5-IPV-Hib-HepB plus PCV7, DTaP5-IPV-Hib-HepB with PCV7 administered 1 month later or a pentavalent DTaP5-IPV/Hib plus HepB plus PCV7 at 15 months of age in a randomized, open-label, phase IIb clinical trial. Immunogenicity endpoints were rates of seroresponse to pertussis toxoid, filamentous hemagglutinin, pertactin and fimbriae types 2 and 3; rates of seroprotection against (Hib) polyribosylribitol phosphate capsular polysaccharide, hepatitis B surface antigen, diphtheria toxoid, tetanus toxoid and poliovirus types 1, 2 and 3; and geometric mean titers to all vaccine antigens. Safety endpoints included solicited injection-site reactions and systemic and serious adverse events.

RESULTS

Seroresponse/seroprotection rates for all antigens exceeded prespecified criteria in both groups that received the hexavalent DTaP5-IPV-Hib-HepB; in the group that received the currently licensed pentavalent vaccine, seroresponse/seroprotection rates exceeded the criteria for all antigens except filamentous hemagglutinin. Seroresponse rates were ≥88.9% for pertussis antigens and seroprotection rates against polyribosylribitol phosphate capsular polysaccharide, hepatitis B surface antigen, diphtheria toxoid, tetanus toxoid and poliovirus antigens were ≥95.1% in recipients of DTaP5-IPV-Hib-HepB.

CONCLUSIONS

DTaP5-IPV-Hib-HepB administered concomitantly with PCV7 or 1 month apart at 15 months of age following the infant series was well-tolerated and elicited antibody responses to all vaccine antigens, with no significant interference from concomitant PCV7 administration (clinicaltrials.gov registration number NCT00362427).

Safety and immunogenicity of a hexavalent vaccine administered at 2, 4 and 6 months of age with or without a heptavalent pneumococcal conjugate vaccine: a randomized, open-label study

BACKGROUND

DTaP₅-IPV-Hib-HepB, an investigational hexavalent combination vaccine, was evaluated for safety and immunogenicity, when administered to infants with heptavalent pneumococcal conjugate vaccine (PCV7).

METHODS

Infants were randomized to receive DTaP₅-IPV-Hib-HepB plus PCV7, DTaP₅-IPV-Hib-HepB with PCV7 administered 1 month later or DTaP₅-IPV/Hib plus HepB plus PCV7 at 2, 4 and 6 months of age in an open-label, phase IIb trial. Vaccine responses were assessed by pertussis toxoid, filamentous hemagglutinin, pertactin and fimbriae types 2/3 seroconversion rates, Haemophilus influenzae type b polyribosylribitol phosphate capsular polysaccharide, hepatitis B surface antigen, diphtheria toxoid, tetanus toxoid and poliovirus types 1, 2 and 3 seroprotection rates and geometric mean titers. Solicited injection site and systemic reactions, serious adverse events, and other safety outcomes were reported.

RESULTS

Seroprotection rates to polyribosylribitol phosphate, hepatitis B surface antigen, diphtheria toxoid, tetanus toxoid and poliovirus antigens across all groups met or exceeded predetermined acceptability criteria. Seroconversion rates to pertussis toxoid, pertactin and fimbriae types 2/3, but not filamentous hemagglutinin, met such criteria. Antidiphtheria antibodies were significantly lower when PCV7 was coadministered. Geometric mean titers to the other antigens of the hexavalent and PCV7 vaccines were all high and similar in the 2 groups. No safety signals were noted.

CONCLUSIONS

DTaP₅-IPV-Hib-HepB administered at 2, 4 and 6 months of age concomitantly with PCV7 was well tolerated and elicited robust antibody responses to all but the antidiphtheria antigens for which there may be evidence of immune interference. Only filamentous hemagglutinin did not meet seroconversion rate acceptability criteria.

Review of diphtheria, tetanus and pertussis vaccines in clinical development

Diphtheria, tetanus and pertussis vaccines have formed the cornerstone of childhood immunization programs for decades. Historically, these have comprised diphtheria and tetanus toxoids combined with inactivated whole-cell pertussis. More recently, advances have been made with the development of purified acellular pertussis vaccines, with improved reactogenicity profiles, and formulation with additional vaccines such as Haemophilus influenzae type b, hepatitis B virus and inactivated poliovirus. Development is currently focused on maximizing the number of vaccines that can be combined in a single formulation and strategies to provide protection against pertussis before the commencement of routine infant immunization.

A combined measles, mumps, rubella and varicella vaccine (Priorix-Tetra): immunogenicity and safety profile

Priorix-Tetra (GlaxoSmithKline Biologicals) is a combined measles, mumps, rubella and varicella (MMRV) vaccine. Eight studies involving more than 3000 children were reviewed. Compared with co-administration of MMR (Priorix) and varicella (Varilrix) vaccines, the MMRV vaccine showed: similar immunogenicity, with immunity shown up to 3 years post-vaccination; a higher rate of fever after the first dose; a slight increase in mild local reactions after the second dose. This MMRV vaccine can be used either as a two-dose vaccine or as a second dose in children primed with separate MMR and/or varicella vaccines, offering a convenient way to introduce varicella vaccination into routine vaccination programmes.

Adverse events following immunization: perception and evidence

PURPOSE OF REVIEW

The aim of this article is to highlight the evidence on new and ongoing vaccine safety concerns in the light of several vaccines recently licensed and others made available and recommended more widely.

RECENT FINDINGS

There is increasingly convincing epidemiologic and laboratory evidence against a causal relation of several alleged adverse events following immunization. The scientific framework to detect and investigate adverse events following immunization is increasingly robust.

SUMMARY

Currently available vaccines are safe in immunocompetent individuals and there is no evidence to deviate from current immunization schedules.