Malaria Vaccine Development Program
Global Problem
Each year, 300 million to 500 million episodes of malaria cause up to 2.5 million deaths, mostly in children. Nonfatal malaria imposes an enormous economic burden of illness, with a major impact on affected communities. The global cost of malaria in terms of lost productivity and medical care exceeds $1.7 billion each year. Available methods to prevent and treat malaria are inadequate - the mosquitoes that transmit the disease have become resistant to insecticides, and the parasites that cause malaria have become resistant to treatment drugs. New technologies are urgently needed. Economic analyses have concluded that the benefits from an effective malaria vaccine would far outweigh the anticipated costs of research and development and program implementation.
In recent years, much evidence has emerged in support of the feasibility of malaria vaccines. New knowledge of the parasite has generated insights into possible methods of vaccine production, and experimental vaccines have demonstrated their capacities to protect against the disease. One experimental vaccine has been tested in large numbers of people but with limited success.
A number of requirements must still be met before a vaccine suitable for large-scale deployment is available. Such a vaccine must satisfy several criteria - it must be suitable for mass production; it must be suitable for use in developing countries; it must protect children; and it must protect a large proportion of the individuals immunized. Although this is a complex task, most experts believe that such a vaccine can be developed.
USAID's Approach
The goal of USAID's Malaria Vaccine Development Program (MVDP) is to accelerate the development of a vaccine that can be used as part of malaria control efforts. For many years, the Program was the principal global effort devoted to developing vaccines to decrease malaria-related childhood illness and death in malaria-endemic areas. Over the years, the Program has shifted its emphasis from research into promising vaccine candidates to producing and testing investigational vaccines. In particular, the MVDP has focused its efforts on developing vaccines against the asexual stages of the parasite, which are likely to be important in protecting against chronic malaria exposure.
The MVDP works closely with academia, the commercial sector, and other government agencies. Experimental vaccines manufactured by several companies (Hoffman-LaRoche, Chiron, and Microgenesys among them) have been tested under the program.
Current Focus
USAID's MVDP has three main thrusts designed to fill the most important gaps in the global malaria vaccine development effort:
- Developing protein recombinant vaccines to protect residents in malaria-endemic areas. This effort, conducted primarily through an interagency agreement with the Walter Reed Army Institute of Research, focuses on the blood stages of the parasite, which are uniquely important for USAID's target populations. The most advanced vaccine of this type is being field-tested in Kenya through funding by the Malaria Vaccine Initiative.
- Developing DNA recombinant vaccines. This new technology holds great promise for developing and producing vaccines and implementing their use in the field. It is at an earlier stage of development than protein vaccine development, however. This work is carried out through an interagency agreement with the Naval Medical Research Center.
- Developing vaccines through "molecular breeding." This technology is akin to breeding animals or plants, but at the molecular level. The approach has the potential of circumventing the ability of malaria parasites to defeat vaccine- induced protection by changing to forms not affected by the vaccine during a malaria episode. This work is through a cooperative agreement with Maxygen, Inc.
Key accomplishments
- Discovery of systems for cultivating different stages of the parasite in the laboratory. The impact of these discoveries on subsequent progress cannot be overestimated.
- Initial discovery of a parasite molecule potentially useful as a vaccine constituent and subsequent discoveries of other molecules that are candidates for vaccine development.
- Numerous tests of investigational vaccines in humans.
USAID Issue Briefs
President's Malaria Initiative (PMI)
- PMI Website
- PMI Fact Sheet
- President's Malaria Initiative (PMI) E-Newsletter
This e-newsletter provides readers with the latest PMI news, country-specific activities, plus Q&A with Admiral R. Timothy Ziemer, U.S. Malaria Coordinator.
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