Malaria Vaccine Development

	Source: ONE/Morgana Wingard

Global Program

There are more than 300-500 million episodes of malaria each year, causing more than 2 million deaths, mostly in children. Non-fatal malaria imposes an enormous economic burden of illness, which has a major impact on the affected communities. Malaria costs more than $1.7 billion each year in medical care and lost productivity. However, 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 the 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 continuing implementation.

The Opportunity

In recent years, much evidence has emerged indicating the feasibility of malaria vaccines. Rapidly accumulating new knowledge of the parasite has allowed powerful insights into possible methods for producing vaccines, and experimental vaccines have been demonstrated capable of protecting against the disease. One vaccine developed by GlaxoSmithKline Biologics and the Walter Reed Army Institute of Research is on track for licensure. However, its efficacy is limited (about 30 percent against clinical disease and 60 percent against severe disease). Vaccines with greater efficacy are needed.

A number of requirements must still be met to develop vaccines with the desired characteristics of high efficacy in very young children, long duration of efficacy, suitability for deployment in the developing world, and cost-effectiveness. Although these are demanding requirements, most experts believe that they can be met.

USAID Accomplishments

The USAID Malaria Vaccine Development Program (MVDP) was for many years the major global effort devoted to developing vaccines to decrease illness and death due to malaria in children in endemic areas. In the early years, the program consisted entirely of research efforts to identify promising approaches. As the knowledge base grew, the program progressively shifted toward testing the approaches identified by the earlier work through the production and testing of investigational vaccines. In particular, the MVDP focused effort on development of vaccines against the asexual stages of the parasite, which are likely to be important in protecting against chronic malaria exposure.

Major MVDP accomplishments include:

• Discovery of systems for cultivating different stages of the parasite in the laboratory; the impact of these discoveries on subsequent progress cannot be overestimated.
• The first discovery of a parasite molecule potentially useful as a vaccine constituent and, subsequently, discovery of other molecules that are candidates for vaccine development.
• Numerous tests of investigational vaccines in humans.

The MVDP works closely with academia, the commercial sector, other government agencies, and international organizations.

Current Focus

The USAID MVDP has two main thrusts, designed to fill the most important gaps in the global malaria vaccine development effort:

• The development of protein-recombinant vaccines to protect residents in endemic areas. This program, which is accomplished primarily through an interagency agreement with the Walter Reed Army Institute of Research, focuses on the blood stages of the parasite, which are responsible for disease and are uniquely important for the USAID target population.
• The development of adenovirus-vectored vaccines. This technology holds great promise as a more effective means of producing the required immune response to protect recipients from disease. This work is through an interagency agreement with the Naval Medical Research Center.
• See the 2010 USAID Research and Development Report to Congress [PDF, 1.3MB] for more details.