The first malaria vaccine could be ready for use by 2015, according to experts reporting encouraging results from a phase III trial, although further data are needed before roll-out.
The vaccine could help avoid many of the nearly 800,000 malaria-related deaths a year, most of which occur in Sub-Saharan Africa. It may also free up some of the 40 per cent of health spending in Africa that goes towards fighting the disease, according to Andrew Witty, chief executive officer of GlaxoSmithKline (GSK), which developed the vaccine collaboration with the PATH Malaria Vaccine Initiative (MVI).
RTS,S/AS01 cuts the risk of developing clinical malaria — typified by chills and high fevers that require medical attention — for children aged 5–17 months over a period of one year by 56 per cent and of developing severe malaria — which affects key organs and can be fatal — by 47 per cent, according to data published online in the New England Journal of Medicine this week (18 October).
The data come from around 6,000 of the more than 15,000 children enrolled in a phase III trial at 11 sites in seven countries in Sub-Saharan Africa. Each child received three doses of vaccine, given at one-month intervals. The one-year efficacy results in infants aged 6–12 weeks are expected to be available in late 2012; and the longer-term efficacy data for all ages by the end of 2014.
The vaccine works in an unusual way, defending the immune system against the parasite Plasmodium falciparum when it first enters a human host’s bloodstream. If approved, it will be the first vaccine against a parasite rather than a virus or a bacterium.
Tsiri Agbenyega, head of the malaria research unit at Komfo-Anokye Hospital in Ghana and a lead researcher at one of the trial sites, said that it is remarkable that the vaccine works and is safe, considering there has never been a successful vaccine against human parasites.
Witty said that the research journey to this point had lasted 25 years. He added that GSK is dedicated to providing the vaccine, once it is approved, at the lowest possible cost.
Any profits from the vaccine will be re-channelled towards the research and development of neglected tropical diseases, according to Witty.
But rollout may be slowed by challenges including funding and capacity to administer the new vaccine and whether donors will fund a vaccine that is only 50 per cent effective when the usual threshold is 90 per cent.
Sally Ethelston, director of communications and advocacy for the PATH MVI said: “We have a history of countries not being ready to roll out vaccines [once they are available]”.
Ethelston said that “a lot of people will be waiting for the next set of data” before committing money.
But she added that PATH MVI is working with governments and organisations “so they are able to make informed decisions” about whether to commit to purchasing and administering the vaccine once it is available. (Munyaradzi Makoni/SciDev)