Journal article

Efficacy of RTS,S malaria vaccine given with EPI vaccines

Malaria vaccine research has been intensified over the past few years with several vaccines tested in trials. RTS,S vaccine has been the most promising of these candidates. The vaccine consists of P falciparum circumsporozoite protein fused to hepatitis B virus surface antigen, expressed in Saccharomyces cerevisiae yeast cells. After initial studies of safety and immunogenicity in American volunteers and a phase 2b study in Gambian adults,7 a phase 2b study in Mozambican children showed that the RTS,S vaccine adjuvanted with ASO2A reduced the incidence of severe malaria episodes in children aged 1—4 years by 49% over 18·5 months; a groundbreaking step in the development of a malaria vaccine.8 The reduction in all clinical episodes in this study was a modest 30%. Since then, further phase 2b trials of RTS,S have been done in younger children in different areas of sub-Saharan Africa. Two studies assessed the efficacy of the vaccine adjuvanted with ASO1E against all clinical episodes over a period longer than 10 months in young children. A study of children aged 5—17 months in Kenya and Tanzania, showed a reduction of 54% in all clinical episodes over 10·5 months of follow-up.9 In Gabon, Ghana, and Tanzania, another study delivered the vaccine alongside vaccines given as part of the expanded programme on immunisation (EPI) with two schedules: 0, 1, and 2 months or 0, 1, and 7 months. As in previous studies, the safety profile of the vaccine was good and the vaccine was well tolerated.

Languages

  • English

Publication year

2011

Journal

The Lancet Infectious Diseases

Volume

10

Type

Journal article

Categories

  • Service delivery

Diseases

  • Malaria

Countries

  • Gabon
  • Ghana
  • Kenya

WHO Regions

  • African Region