Maputo — Maputo, 9 Nov (AIM) The latest results from the phase III clinical trial of the RTS,S malaria candidate vaccine, published online on Friday in the New England Journal of Medicine, show that the vaccine can indeed help protect African infants against malaria.
According to a press release from the drug company GlaxoSmithKline (GSK) and the PATH Malaria Vaccine Initiative (MVI), the key finding was that When compared to immunization with a control vaccine, infants (aged 6-12 weeks at first vaccination) vaccinated with RTS,S had one-third fewer episodes of both clinical and severe malaria and had similar reactions to the injection. In this trial, RTS,S demonstrated an acceptable safety and tolerability profile.
The Manhica Health Research Centre in the southern Mozambican district of Manhica is one of 11 African research centres in seven countries that are conducting this trial, with grant funding from the Bill & Melinda Gates Foundation to MVI.
One of the researchers, Dr Salim Abdulla of Tanzanian, Weve made significant progress in recent years in our battle against malaria, but the disease still kills 655,000 people a yearmainly children under five in sub-Saharan Africa. An effective malaria vaccine would be a welcome addition to our tool kit, and weve been working toward this goal with this RTS,S trial
This study, he added, indicates that RTS,S can help to protect young babies against malaria. Importantly, we observed that it provided this protection in addition to the widespread use of bed nets by the trial participants.
The trial showed that, when administered along with the standard childhood vaccines, the efficacy of RTS,S in infants aged six to 12 weeks (at first vaccination) against clinical and severe malaria was 31% and 37%,3 respectively, over 12 months of follow-up after the third vaccine dose.
But the results were disappointing in that protection was less than that provided to rather older children in a trial of RTS,S last year. In that earlier trial the efficacy observed with RTS,S in children aged 5-17 months of age against clinical and severe malaria was 56% and 47%, respectively.
This rather surprising result makes us even more eager to gather and analyze more data from the trial to determine what factors might influence efficacy against malaria and to better understand the potential of RTS,S in our battle against this devastating disease, said Abdulla. We were also glad to see that the study indicated that RTS,S could be administered to young infants along with standard childhood vaccines and that side effects were similar to what we would see with those vaccines.
Andrew Witty, the Chief Executive Office of GSK, said While the efficacy seen is lower than last year, we believe these results confirm that RTS,S can help provide African babies and young children with meaningful protection against malaria. They take us another important step forward on the journey towards having a new intervention available against this disease, which is a huge burden on the health and economic growth of Africa.
We remain convinced that RTS,S has a role to play in tackling malaria and we will continue to work with our partners and other stakeholders to better understand the data and to define how the vaccine could best be used to provide public health benefit to children in malaria endemic areas in Africa, Witty added.
David Kaslow, Director of the Malaria Vaccine Initiative, said Determining the role of RTS,S in Africa will depend on analyses of additional data. We are now an important step closer to that day.
Success in developing malaria vaccines depends on many factors: at the top of the list are partnerships and robust evidence, coupled with an understanding that different combinations of tools to fight malaria will be appropriate in different settings in malaria-endemic countries.
Bill Gates admitted that the efficacy of the candidate vaccine came back lower than we had hoped, but developing a vaccine against a parasite is a very hard thing to do. The trial is continuing and we look forward to getting more data to help determine whether and how to deploy this vaccine.
The RTS,S malaria vaccine candidate has been under development since the 1980s, and the African countries involved in the research include Mozambique, Burkina Faso, Gambia, Ghana, Kenya, Malawi and Tanzania.
The Phase III safety and efficacy trial began in May 2009. The study has enrolled 15,460 infants and children in two age groups, 5-17 months and 6-12 weeks of age at the time of the first vaccination.