Interim results from RTS,S vaccine on-going phase III trial on malaria

According to the World Health Organization (WHO), more than 250 million clinical malaria cases are attributed to Plasmodium falciparum (Pf) annually, with over 1.1 million deaths in sub-Saharan Africa alone.

This week the world, and especially the malaria vaccine development community, welcomed the second disclosure of interim results of the on-going phase III RTS,S vaccine efficacy trial in seven African countries.  GlaxoSmithKline (UK) and the PATH - Malaria Vaccine Initiative (PATH MVI, USA) - who jointly developed the RTS,S vaccine - published the first interim results for the cohort of children six to twelve weeks old.  The vaccine proved to be safe and protect infants against clinical malaria.  The results demonstrate a slightly higher protection than the study hypothesis, and they met the pre-defined efficacy criteria.  Vaccine efficacy against clinical malaria was 31% in the per-protocol population, and efficacy against severe malaria was 26% in the intention-to-treat population¹.  Not surprisingly, for both end points, the efficacy was lower in infants than older children.

RTS, S has been under development for more than 25 years, and the pivotal phase III efficacy trial will run until 2014.  Only after completion of the trial, full statistical analysis of all the data and consensus by all malaria Stakeholders, can decisions be made on the future and deployment of RTS,S.

While these results are comforting, a need still exists for further improvement of the malaria vaccine.  Therefore EVI urges continued and sustainable support for second generation Malaria vaccines.  Dr Odile Leroy, Executive Director of European Vaccine Initiative (EVI) "We have come a long way in Malaria vaccine development, and the recent results of the RTS,S efficacy trial are a major step in the development of malaria vaccines. It is unambiguously clear that a highly effective malaria vaccine is not yet within reach, and can only be attained by sustainable funding and development efforts for the next decade."