The world's first malaria vaccine may be available within two years, the World Health Organisation has said. Dr Simon Kariuki, the principal investigator at the Siaya trial site said trials have showed the vaccine can prevent nearly half of all malaria cases in children.
"In Kenya it will have a big impact. We lose 33,000 people to malaria every year and 90 per cent of those are children," he said. Kariuki said the vaccine, known as RTSS, is being developed by British pharmaceutical firm GlaxoSmithKline. He said trials are taking place in Kenya and six other African countries.
Yesterday Kariuki said if the vaccine is cleared by the European Medicines Agency next year, it could be used on children as early as 2015. "It can reduce that by half in terms of burden to family and health infrastructure. About 60 per cent of hospital admissions are largely due to malaria," he said
Kenyan scientists involved in the study said this could save the country billions of shillings in health-care expenses. The vaccine, made to be sold only in Africa, is being tested at 11 sites across the seven African countries.
Kenya hosts three of those sites in Siaya, Kombewa near Kisumu and Kilifi. They are run by the Kenya Medical Research Institute in partnership with the CDC, US Army Walter Reed Medical Centre, and the Wellcome Trust respectively.
The results were released officially in Durban, South Africa, yesterday. They showed that after 18 months of follow-up, children aged 5-17 months and vaccinated with RTSS experienced 46 per cent fewer cases of malaria, compared to children immunised with a control vaccine.
"Over 18 months of follow-up, 444 cases of clinical malaria were prevented for every 1,000 infants vaccinated," the study reported. The vaccine was less effective in babies. Infants who had the jabs when they were just a few weeks old were 27% less likely to suffer from malaria.
Halidou Tinto, chair of a committee that oversaw the RTSS Phase III trial said scientists will now investigate whether a booster dose can increase protection in the longer term. "Preventing substantial numbers of malaria cases in a community would mean fewer hospital beds filled with sick children. Families would lose less time and money caring for these children and have more time for work or other activities," he said.
Tinto said Menengitis occurred in some of the children given the vaccine but the researchers said no other safety signal was identified. "The occurrence of meningitis will be followed closely during the remainder of the trial," he said. Most children and infants in the trial also used existing malaria prevention measures such as insecticide treated bed nets.
Malaria kills about 660,000 children in sub-Saharan Africa every year. The vaccine candidate works by triggering the immune system to defend against the malaria parasite when it first enters the human bloodstream.
It prevents the parasite from infecting, maturing, and multiplying in the liver, after which time the parasite would re-enter the bloodstream and infect red blood cells, leading to malaria symptoms. The trials and vaccine development are funded with more than US$200 million in grant monies mostly from the Bill & Melinda Gates Foundation. and GSK.