International Malaria Vaccines For The World Conference To Showcase Scientific Push For "next Generation" Products
Malaria experts from around the world are gathering in Washington this week to discuss cutting edge research into a new generation of malaria vaccines that includes efforts to construct a genetically engineered "DNA vaccine," to uncover new vaccine targets that appear early in malaria infections, and to develop immunizations that could block malaria transmission between mosquitoes and humans.
The reports from the frontlines of malaria vaccine research will be delivered at the Second International Malaria Vaccines for the World Conference, to be held September 28-30 in Washington, DC, which will feature an extensive discussion of the portfolio of projects supported by the PATH Malaria Vaccine Initiative (MVI). MVI is committed to developing vaccines that can help eradicate a disease that kills nearly 900,000 people each year, most of them children in sub-Saharan Africa.
"We are eager to build on the progress we have made in the last 10 years and are challenging the malaria vaccine community and others to produce innovations that will enable us to eliminate this disease once and for all," said Dr. Christian Loucq, director of MVI.
MVI is currently partnering with GlaxoSmithKline (GSK) Biologicals and research centers across Africa to conduct Phase 3 testing of GSK's RTS,S malaria vaccine, the world's most clinically advanced malaria vaccine candidate. If successful in Phase 3 testing and licensure, RTS,S could satisfy the intermediate goal set forth in the international community's Malaria Vaccine Technology Roadmap of a "first-generation" malaria vaccine that is at least 50 percent effective against severe disease and death and lasts more than one year.
Diversity of new approaches
Much of the research to be presented at the MVI portfolio session at the World Conference is focused on identifying and developing new malaria vaccine targets and approaches. MVI is already laying the foundation for a next-generation vaccine that is at least 80 percent effective against clinical disease and lasts longer than four years. Even more ambitiously, MVI is supporting the development of vaccine approaches that fight malaria by interrupting its transmission from mosquitoes to humans.
Blocking transmission of malaria to others
Rhoel Dinglasan of the Johns Hopkins Bloomberg School of Public Health (JHSPH) will offer an update, including preclinical results, on the partnership involving JHSPH, MVI, and the Sabin Vaccine Institute to develop a transmission-blocking vaccine. The project is focused on an antigen found in malarial mosquitoes called AnAPN1, which appears to play a major role in malaria parasite establishment within the mosquito.
Preliminary field research has shown that antibodies induced by this antigen are capable of blocking transmission of the two deadliest malaria parasites, Plasmodium falciparum and P. vivax. When a mosquito takes blood from a person vaccinated with these antibodies, disease transmission would be interrupted by preventing the parasite from attaching to and invading the mosquito's gut. Interrupting this critical step in the life cycle of the parasite would serve to reduce the number of infected mosquitoes in endemic areas, thereby reducing subsequent rates of transmission to humans. Such a vaccine approach is viewed as being a critical tool to support efforts to eliminate malaria in the future.
Expanding the malaria vaccine antigen library
Patrick Duffy, an investigator with the National Institute of Allergy and Infectious Diseases (NIAID) who also heads the malaria program at Seattle BioMed, will provide an update on new efforts to identify promising targets for a malaria vaccine, focusing on the pre-erythrocytic stage, before the parasite reaches the bloodstream.
"We are moving quickly to provide vaccine developers with specific antigens that could improve the effectiveness of immunizations by forcefully engaging the disease soon after the parasite enters into the body," Duffy said.