African governments urged to support malaria research
A researcher with the Kintampo Health Research Centre, Dr Kwaku Poku Asante, has called on African governments to give more support to malaria research to help reduce the burden of malaria.
He said there was the need for other innovative tools such as a vaccine to complement existing malaria control tools such as insecticide treated nets.
“Though there is marginal reduction in malaria worldwide, our hospital wards get filled with many children with malaria and malaria-related complications each year. The RTS,S Malaria vaccine being tested in Africa has the potential to avert several cases of malaria. If the results of the trials are acceptable to African regulatory authorities and the World Health Organisation, there will be the need for African governments and their development partners to fund more innovative research in delivering the vaccine to children who need it most,” he said.
Dr Asante, who is the Principal Investigator for the RTS,S vaccine and Co-chair of the Clinical Trials Partnership Committee (CTPC), an international committee of researchers and their collaborators who oversee the RTS,S Phase III programme in Africa, made the call at the 62nd Annual Meeting of the American Society of Tropical Medicine and Hygiene in the USA.
Results of RTS,S trial
Speaking on the potential impact of a malaria vaccine undergoing clinical trials, he said the public health impact of a leading malaria vaccine candidate known as the GSK RTS,S malaria vaccine had been evaluated in the context of existing malaria control measures, such as insecticide treated bed nets in a large-scale Phase III trial in Africa.
The latest results, which were done over 18 months of follow-up, showed that children aged five to 17 months at first vaccination with RTS,S experienced 46 per cent fewer cases of clinical malaria, compared to children immunised with a control vaccine.
An average of 941 cases of clinical malaria were prevented over 18 months of follow-up for every 1,000 children vaccinated in this age group, indicating that a child could contract more than one case of malaria.
According to Dr Asante, severe malaria cases were reduced by 36 per cent; 21 cases of severe malaria were prevented over 18 months of follow-up for every 1,000 children vaccinated. Malaria hospitalisations were reduced by 42 per cent.
Infants aged six to12 weeks at first vaccination with RTS,S had 27 per cent fewer cases of clinical malaria.
Over 18 months of follow-up, 444 cases of clinical malaria were prevented among every 1,000 infants vaccinated. The reduction in severe malaria cases and malaria hospitalisations by 15 per cent and 17 per cent respectively was not statistically significant.
He said overall, vaccine efficacy declined over time, adding that previous results from one year follow-up of the Phase III trial showed that efficacy of RTS,S was 56 per cent against clinical malaria and 47 per cent against severe malaria for the five to 17-month-old age group and 31 per cent against clinical malaria and 37 per cent against severe malaria in the six to 12-week-old age group.
Dr Asante said the RTS,S vaccine continued to show an acceptable safety and tolerability profile during the 18-month follow-up.
However, researchers continued to monitor the occurrence of meningitis that had been previously reported, though unrelated to the vaccine administration.
He said further data from 32 months follow-up and the impact of a fourth 'booster' dose given 18 months after the initial three doses were expected to become available in 2014.
Eleven African research centres in seven African countries are conducting the trial, together with GlaxoSmithKline (GSK) and the PATH Malaria Vaccine Initiative (MVI), with grant funding from the Bill & Melinda Gates Foundation to MVI.