09 Dec 08

Malaria is one of the world's biggest killers and is responsible for over a million deaths every year.

Clinical trials of a new malaria vaccine have shown it provides both infants and young children with substantial protection against malaria.

And in other work, a second Oxford University team have discovered how simple and cheap treatment can save lives by buying the time necessary for children with severe malaria in rural areas of Asia and Africa to get to a clinic for full treatment.

The first studies - of the RTS,S vaccine candidate developed by GlaxoSmithKline Biologicals were conducted in Kenya and Tanzania as part of a global effort led by The PATH Malaria Vaccine Initiative (MVI) to develop a malaria vaccine, with Oxford University scientists leading the work in Kilifi, Kenya.

The results of two separate phase II trials of the vaccine were presented at the American Society for Tropical Medicine and Hygiene (ASTMH) conference and are published in the New England Journal of Medicine.

In children aged 5-17 months, the vaccine candidate was found to be 56 percent effective in preventing clinical disease.

The second trial showed for the first time that the vaccine can be safely and easily administered in infants as part of existing national immunisation programs.

The findings support efforts to launch large-scale phase III trials of the vaccine starting in 2009 across Africa. This would seek to determine the length of the vaccine’s protection and evaluate its effectiveness in different parts of Africa.

Malaria currently kills almost one million people each year – most of them young children in Africa, the intended recipients for this new vaccine candidate.

Oxford University scientists based at the Kenya Medical Research Institute (KEMRI) Wellcome Collaborative Research Programme were involved in the trial involving children aged 5-17 months. They discovered the RTS,S/AS01 vaccine formulation reduces clinical malaria episodes by 56 percent for up to an average of eight months.

‘These findings build a solid case for phase III testing, which the partners in this endeavour are looking forward to starting in the near future,’ said the study’s lead author, Dr Philip Bejon of Kenya Medical Research Institute (KEMRI) Wellcome Collaborative Research Programme and the Centre for Tropical Medicine, University of Oxford. 

The second set of research was carried out by a team including the World Health Organisation and researchers from Oxford University and is reported in The Lancet.

Professor Nick White of the Centre for Tropical Medicine, University of Oxford and the Faculty of Tropical Medicine, Mahidol University, Thailand says: ‘We’ve shown that children with severe malaria who are hours from a health clinic and too ill to take their medicine by mouth can be given a single, simple suppository. This knocks down the malaria parasites in the blood and buys life-saving time to get the children to a clinic for proper diagnosis and full treatment. It costs about 10p to make and can be easily administered by people in the community.’

The trial found that the administration of the rectal suppository by a trained lay community member or caregiver reduces the risk of death or disability by half in patients in rural villages with severe malaria, who can’t be treated orally and can’t access injections for several hours. The risk is reduced from 4% to 2%.

‘Worldwide there are 10 million deaths of children under 5 every year. One million of these are from malaria, of which about 90% are in rural Africa,’ says Professor White. ‘Every death could be prevented by prompt treatment using existing drugs, but it’s difficult to treat all children fast enough, especially in rural areas. This helps get over the lack of health infrastructure. You’re buying time with a cheap rectal suppository and, if you’re several hours away from a clinic, it can be the difference between life and death.’