A randomized study to evaluate the immunogenicity and safety of a heptavalent diphtheria, tetanus, pertussis, hepatitis B, poliomyelitis, haemophilus influenzae b, and meningococcal serogroup C combination vaccine administered to infants at 2, 4 and 12 months of age

Efficacy, safety, and formulation issues of the combined vaccines

Introduction: Controlling the preventable infectious diseases is the main goal of vaccination. Among the vaccines, combined vaccines are of great importance for their social, public health, and economic values. It is stated that the combined vaccines are as efficient and safe as the monovalent vaccines. However, a concern has raised about the efficacy and safety of the combined vaccines due to the outbreaks of vaccine-preventable diseases and occurrence of serious adverse events. Areas covered: A retrospective literature search was conducted in the Google Scholar and PubMed databases to evaluate the efficacy and safety of the combined vaccines from 1980 to 2020 using appropriate keywords. Expert opinion: Several studies have shown efficacy and safety issues related to the combined vaccines. Different factors contribute to the inefficacy and lack of safety in the vaccines including formulation problems, limited data in the pre-licensure studies and challenges related to imperfection of the post-licensure surveillance systems. For surmounting the mentioned obstacles, there is a need to provide new formulations of the vaccines, revise the vaccines҆ safety and efficacy acceptance standards in the pre-licensure studies, improvement of post-licensure surveillance systems, and education of healthcare staff.

Infant vaccine co-administration: review of 18 years of experience with GSK's hexavalent vaccine co-administered with routine childhood vaccines

INTRODUCTION

The benefits of vaccine co-administration include improved vaccine acceptance and uptake resulting in an increased coverage and protection against multiple childhood diseases, with minimal medical visits. The diphtheria-tetanus-acellular pertussis-hepatitis B-poliomyelitis-Haemophilus influenzae type b vaccine (DTaP-HBV-IPV/Hib) has been available for more than 19 years and is recommended for co-administration with several other infant vaccines.

AREAS COVERED

This is a comprehensive review (34 studies, 21,000 participants) describing the immunogenicity and safety of DTaP-HBV-IPV/Hib when co-administered with 12 different vaccines in infants including pneumococcal, meningococcal, rotavirus or measles-mumps-rubella-varicella.

EXPERT OPINION

Interactions among co-administered vaccines are complex. Therefore, co-administration data are critical before a vaccination regimen can be recommended. Co-administration of DTaP-HBV-IPV/Hib with other routinely administered vaccines was associated with high percentages of children achieving seroprotection/vaccine response against DTaP-HBV-IPV/Hib antigens. In addition, co-administration was not associated with clinically significant interference in immune responses to co-administered vaccines and was well tolerated. Increased systemic reactions observed with some combinations (DTaP-HBV-IPV/Hib + pneumococcal conjugate or meningococcal serogroup B vaccines) were mitigated by prophylactic paracetamol administration. The data reported here, which represent the most frequently used co-administrations of DTaP-HBV-IPV/Hib worldwide, support the concomitant administration of DTaP-HBV-IPV/Hib with other routinely recommended infant vaccines.

The Immunogenicity and Safety of a Combined DTaP-IPV//Hib Vaccine Compared with Individual DTaP-IPV and Hib (PRP~T) Vaccines: a Randomized Clinical Trial in South Korean Infants

Recommended infant vaccination in Korea includes DTaP-IPV and Hib vaccines administered as separate injections. In this randomized, open, controlled study we assessed the non-inferiority of immunogenicity of DTaP-IPV//Hib pentavalent combination vaccine (Pentaxim™) compared with licensed DTaP-IPV and Hib (PRP~T) vaccines. We enrolled 418 healthy Korean infants to receive either separate DTaP-IPV and Hib vaccines (n = 206) or the pentavalent DTaP-IPV//Hib (n = 208) vaccine at 2, 4, 6 months of age. Antibodies to all components were measured before the first vaccination and one month after the third, and safety was assessed after each vaccination including recording of reactions by parents. We confirmed the non-inferiority of DTaP-IPV//Hib compared with DTaP-IPV and Hib vaccines; 100% of both groups achieved seroprotection against D, T, IPV and PRP~T, and 97.5%-99.0% demonstrated seroresponses to pertussis antigens. Antibody levels were similar in both groups, except for those to the Hib component, PRP~T. In separate and combined groups geometric mean concentrations of anti-PRP~T antibodies were 23.9 and 11.0 μg/mL, respectively, but 98.3% and 97.4% had titers ≥ 1 μg/mL, indicative of long-term protection. All vaccines were well tolerated, with no vaccine-related serious adverse event. Both groups had similar safety profiles, but the combined vaccine group had fewer injection site reactions. The immunological non-inferiority and similar safety profile of DTaP-IPV//Hib vaccine to separate DTaP-IPV and Hib vaccines, with the advantage of fewer injections and injection site reactions, supports the licensure and incorporation of DTaP-IPV//Hib into the Korean national vaccination schedule (Clinical trial registry, NCT01214889).

[Immunisation schedule of the Spanish Association of Paediatrics: 2016 recommendations]

The Advisory Committee on Vaccines of the Spanish Association of Paediatrics (CAV-AEP) annually publishes the immunisation schedule which, in our opinion, estimates optimal for children resident in Spain, considering available evidence on current vaccines. We acknowledge the effort of the Ministry of Health during the last year in order to optimize the funded unified Spanish vaccination schedule, with the recent inclusion of pneumococcal and varicella vaccination in early infancy. Regarding the funded vaccines included in the official unified immunization schedule, taking into account available data, CAV-AEP recommends 2+1 strategy (2, 4 and 12 months) with hexavalent (DTPa-IPV-Hib-HB) vaccines and 13-valent pneumococcal conjugate vaccine. Administration of Tdap and poliomyelitis booster dose at the age of 6 is recommended, as well as Tdap vaccine for adolescents and pregnant women, between 27-36 weeks gestation. The two-dose scheme should be used for MMR (12 months and 2-4 years) and varicella (15 months and 2-4 years). Coverage of human papillomavirus vaccination in girls aged 11-12 with a two dose scheme (0, 6 months) should be improved. Information for male adolescents about potential beneficial effects of this immunisation should be provided as well. Regarding recommended unfunded immunisations, CAV-AEP recommends the administration of meningococcal B vaccine, due to the current availability in Spanish communitary pharmacies, with a 3+1 scheme (3, 5, 7 and 13-15 months). CAV-AEP requests the incorporation of this vaccine in the funded unified schedule. Vaccination against rotavirus is recommended in all infants. Annual influenza immunisation and vaccination against hepatitis A are indicated in population groups considered at risk.