Safety and Immunogenicity of ChAd63 and MVA ME-TRAP in West African Children and Infants

Mol Ther. 2016 Aug;24(8):1470-7. doi: 10.1038/mt.2016.83. Epub 2016 Apr 25.

Abstract

Malaria remains a significant global health burden and a vaccine would make a substantial contribution to malaria control. Chimpanzee Adenovirus 63 Modified Vaccinia Ankara Multiple epitope thrombospondin adhesion protein (ME-TRAP) and vaccination has shown significant efficacy against malaria sporozoite challenge in malaria-naive European volunteers and against malaria infection in Kenyan adults. Infants are the target age group for malaria vaccination; however, no studies have yet assessed T-cell responses in children and infants. We enrolled 138 Gambian and Burkinabe children in four different age-groups: 2-6 years old in The Gambia; 5-17 months old in Burkina Faso; 5-12 months old, and also 10 weeks old, in The Gambia; and evaluated the safety and immunogenicity of Chimpanzee Adenovirus 63 Modified Vaccinia Ankara ME-TRAP heterologous prime-boost immunization. The vaccines were well tolerated in all age groups with no vaccine-related serious adverse events. T-cell responses to vaccination peaked 7 days after boosting with Modified Vaccinia Ankara, with T-cell responses highest in 10 week-old infants. Heterologous prime-boost immunization with Chimpanzee Adenovirus 63 and Modified Vaccinia Ankara ME-TRAP was well tolerated in infants and children, inducing strong T-cell responses. We identify an approach that induces potent T-cell responses in infants, which may be useful for preventing other infectious diseases requiring cellular immunity.

Publication types

  • Clinical Trial

MeSH terms

  • Adenoviruses, Simian*
  • Africa, Western / epidemiology
  • Animals
  • Antibodies, Protozoan / blood
  • Antibodies, Protozoan / immunology
  • Child
  • Child, Preschool
  • Enzyme-Linked Immunospot Assay
  • Epitopes* / immunology
  • Gambia
  • Genetic Vectors* / adverse effects
  • Humans
  • Immunization, Secondary
  • Infant
  • Infant, Newborn
  • Malaria / epidemiology
  • Malaria / prevention & control*
  • Malaria Vaccines / administration & dosage
  • Malaria Vaccines / adverse effects
  • Malaria Vaccines / immunology*
  • Outcome Assessment, Health Care
  • Vaccinia virus*

Substances

  • Antibodies, Protozoan
  • Epitopes
  • Malaria Vaccines