For centuries, the Chinese have referred to malaria as the "Mother of all Fevers." In adults, the parasite causes relapsing illness debilitating enough to cost some African nations up to five percent of their GNP. But when the worst type of malaria strikes infants, 30 percent may die. Of the more than one million people that malaria kills annually, the vast majority are under five years old.
Effective weapons in the fight against malaria include insecticide-treated bednets, mosquito control, prompt and effective malaria treatment for children, and presumptive treatment for pregnant women. But the best hope may ultimately be a vaccine. That is the mission of the PATH Malaria Vaccine Initiative (MVI).
MVI and GlaxoSmithKline (GSK) Biologicals Release Data Showing Vaccine Candidate Can Reduce Malaria in Children Ages 1-4.
The findings from MVI's phase 2b RTS,S malaria vaccine trial in Mozambique were published in the October 16, 2004 and November 15, 2005 issues of The Lancet. The trial, which involved 2,022 children in southern Mozambique, was conducted by the Centro de Investigação em Saude da Manhiça (CISM) and co-sponsored by GSK Biologicals and MVI. The foundation has awarded grants totaling $287 million to support MVI. For more information about the trial results, visit the MVI Web site or The Lancet.com.
Created in 1999 with a $50 million grant from the Gates Foundation, MVI is specifically designed to forge partnerships among the diverse players in vaccine development. MVI identifies promising vaccine candidates and drives them through development into clinical trials. In 2003, the foundation announced an additional $100 million in funding for MVI to further expand the malaria vaccine development pipeline, accelerate the movement of promising vaccine candidates into clinical trials, and address financial and policy barriers to vaccine development. A third grant, for $107.6 million, was announced in 2005 to complete development of the RTS,S malaria vaccine candidate. In 2006, the foundation made an additional $29.3 million grant to MVI to support initial testing of a novel, whole-parasite vaccine candidate.
 MVI's first goal is to find a vaccine that can prevent or reduce deaths in infants and young children. A proof-of-concept trial in Mozambique on the most advanced malaria vaccine candidate, the RTS,S vaccine, found it offered partial protection from severe malaria in children age one to four. The trials were conducted in coordination with GSK Biologicals, Mozambique's Ministry of Health, CISM, and the Hospital Clinic of the University of Barcelona. Results were published in the October 16, 2004 issue of The Lancet.
The RTS,S vaccine is a good example of MVI's crucial role in vaccine development. Two decades ago, drug companies recognized it as a promising malarial vaccine, but without effective market demand, research was placed on the back burner. Now, MVI is delivering the capital and energy needed to drive RTS,S research forward. MVI is also investigating other potential vaccines. By advancing several candidates simultaneously, the timeline to worldwide malarial control could be shortened.
In the average time required to read this Web page, four children will die of malaria. An effective vaccine could help change that. By linking researchers and pharmaceutical companies with clinical institutions in malaria-endemic countries, MVI hopes to give a future to thousands of children now at risk.
The Challenge: Building Vaccines Through Cooperation
"Finding a vaccine for Malaria is like trying to solve a three-dimensional jigsaw puzzle," says Dr. Regina Rabinovich, director of the Gates Foundation's Infectious Diseases program. Vaccines are most commonly developed to fight viruses, such as polio. But malaria is a parasite, more complex than a virus. As it invades and infects humans, it periodically sequesters itself inside red blood cells or the liver, evolving as it matures.
 Creating a highly effective vaccine will almost certainly require a compound directed at multiple antigens, or proteins, on the surface of the organism. This complicates both the development and the clinical trials necessary to bring any vaccine to the point of delivery. And complicated development and testing demands enormous capital investment, with no certainty of profit.
Malaria thrives in the hot and humid regions where mosquitoes breed, geographically coinciding with some of the world's poorest nations. Getting an effective vaccine through the financial and clinical barriers to these markets demands coordinated efforts from diverse partners. Scientists, pharmaceutical laboratories, governmental institutions, and regional health workers must all work together. MVI is helping to build these platforms of cooperation.
Did You Know?
- RTS,S is a recombinant polypeptide malaria protein ingeniously fused to the surface of a Hepatitis B protein. Attaching the malarial surface protein to the Hepatitis viral particles increases the vaccine's capacity to stimulate an effective immune response.
- It takes an average 15 years for a proven vaccine to reach developing countries after licensure in industrialized nations. In the interim, millions of people die of preventable disease.
Updated October 2007
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