Gates Foundation funding aids clinical evaluation of malaria vaccine

The Bill & Melinda Gates Foundation has made a $107.6m grant to the PATH Malaria Vaccine Initiative (MVI) in order to extend the public-private partnership between MVI and GlaxoSmithKline Biologicals (GSK Bio) for the development of GSK's malaria vaccine for children in Africa.

The grant will allow for the expansion of clinical evaluation of the world's most advanced malaria vaccine candidate, known as RTS,S, directly supporting clinical trials in Africa. If all the project milestones are achieved, the period of the agreement should see the vaccine through licensure and introduction to African immunisation programmes. GSK will at least match the $21.4 million it receives from MVI to help defray some of the clinical development costs.

RTS,S targets the parasite as it is transmitted by mosquitoes, meaning that it interferes with the malaria parasite's ability to cause disease in humans. The antibodies and white blood cells produced after immunisation prevent the parasite from surviving or from developing further in the liver.

The results of a proof-of-concept trial in Mozambique in 2004, published in the British medical journal The Lancet, showed vaccine efficacy against clinical malaria attacks to be 30%. Efficacy against infection was 45% while efficacy against severe disease was 58% in children aged one to four.

The new trials, which will take place in several African countries, will include studies to assess the vaccine in younger age groups, including infants, which are the groups that suffer most from malaria.

Jean Stephenne, president of GSK Bio, said: 'Approximately five years of work will be required before this vaccine is ready for licensure and implementation, but the international community must already begin preparing the environment for this vaccine so that it can reach those who are in greatest need as quickly as possible.'

MVI and GSK Bio first entered into collaboration in 2000 to develop the vaccine for children after a $50m grant from the Gates Foundation. While continuing to make significant investments in the clinical development of the vaccine, GSK Bio will also begin preparations for large-scale manufacturing, registration, and supply of the vaccine should it prove to be effective. Along with MVI it has developed a specific framework on pricing and supply of the vaccine in their collaboration agreement: 'GSK will provide the vaccine to public-sector markets in poor countries at prices that support its reliable, long-term production and distribution to children who need it most,' the company says.

Among infectious diseases, malaria is one of the world's biggest killers, claiming more than one million victims in the world's poorest countries and more children in sub-Saharan Africa than any other infectious disease. The economic costs of the disease for Africa alone are equivalent to US$12bn annually.