Generic Bexsero vaccine suspension for injection 0.5ml pre-filled syringes

4CMenB vaccine is authorized for protection against serogroup B invasive meningococcal disease (IMD). This study synthesized real-world evidence (RWE) data on effectiveness and impact of 4CMenB vaccine. A systematic search identified RWE on vaccine effectiveness (VE) and vaccine impact of 4CMenB in infants, children and adolescents. A meta-analysis was conducted of 4CMenB VE against serogroup B-IMD in infants and children. The primary meta-analysis used a random-effects model on data from five studies from five countries reporting VE in fully vaccinated infants and children, and estimated pooled VE at 79.7% (95% confidence interval 70.4, 86.1). In sensitivity analyzes, inclusion/exclusion of studies from the primary analysis did not materially change the results. Age-specific data in adolescents were summarized qualitatively. Data identified from Australia reported high effectiveness and impact in adolescents. This meta-analysis provides evidence of high 4CMenB VE against serogroup B-IMD in fully vaccinated infants and children across different geographic regions. Clinical trial registration: N/A.

Abstract licence: CC BY

BackgroundAcute lymphoblastic leukemia is the most prevalent childhood cancer and the leading cause of cancer mortality before the age of 20. Although therapeutic advances have significantly improved survival, children and adolescents treated for acute lymphoblastic leukemia remain vulnerable to infections, largely preventable by vaccination, due to humoral and cellular immune dysfunction induced by disease and treatment.Materials and methodsThis systematic review, based on electronic databases, aims to evaluate antibody levels associated with potential protective immunity against vaccine antigens for diphtheria, pertussis, tetanus, poliomyelitis, Haemophilus influenzae type b, measles, mumps, rubella, influenza, varicella-zoster virus, yellow fever, pneumococcal, and meningococcal diseases in children and adolescents treated for acute lymphoblastic leukemia after completion of chemotherapy.ResultsA total of twenty-four studies published between 1981 and 2023 were included, comprising 1110 children and adolescents. Protective antibody levels ranged from 11% to 97% for diphtheria, 0% to 90% for pertussis, 20% to 100% for tetanus, and 11% to 95% for poliomyelitis. Haemophilus influenzae type b, protection ranged from 16.7% to 100%. Viral vaccines also showed heterogeneous responses, with protection rates of 25-79% for mumps, 16-86% for measles, 35-98% for rubella, and 23-75% for varicella-zoster virus. Antibody responses to pneumococcal and meningococcal vaccines were consistently low, with protection rates of 5-38% for pneumococcal studies and 12% in a single meningococcal study.ConclusionsThis review found a consistent and clinically relevant loss of vaccine-induced immunity in children and adolescents treated for acute lymphoblastic leukemia. The recommendation of vaccine booster doses for this vulnerable population, irrespective of serological status, may represent a more practical approach to ensuring adequate post-chemotherapy treatment protection.

Abstract licence: CC BY