Science Magazine published medical research online Sept. 8 about a promising new malaria vaccine developed by a team led by a Navy scientist, marking the first time the magazine published an article about a clinical trial of a malaria vaccine.
Capt. Judith Epstein, a Naval Medical Research Center (NMRC) researcher with the U.S. Military Malaria Vaccine Program (USMMVP), led a team of military and civilian research scientists in developing a vaccine against malaria, a life-threatening disease for which there is currently no licensed vaccine.
The discovery of a highly effective vaccine is an important biomedical research and development priority for Navy Medicine because of the significant impact malaria has had and continues to have on the readiness of the U.S. military.
While additional studies are required, Epstein is pleased with the groundbreaking work the team has made to date.
"Our goal is to protect the lives and welfare of our military personnel," said Epstein. "We need a vaccine which is as effective against malaria as the vaccines we use every day to prevent other life-threatening diseases. Also, the Department of Defense has a long tradition of transitioning life-saving vaccines and drugs to the developing world; if we are successful, a vaccine used to protect our Sailors and Marines could also be used to save thousands of lives in malaria-endemic areas."
The initial research for a malaria vaccine began in the 1970s in studies by the Navy and the University of Maryland in which volunteers were exposed to bites from mosquitoes harboring weakened malaria parasites. Using radiation-attenuated sporozoites delivered by mosquito bite, researchers achieved sustained sterile protection. A sporozoite is a form of the malaria parasite that is concentrated in the salivary glands of an infected mosquito and is introduced into a person's blood when the mosquito bites.
Today, the approach being pursued by Navy researchers and their partners capitalizes on these prior studies. The recent published results focus on the first-in-humans clinical trial of the PfSPZ (Plasmodium falciparum sporozoite) vaccine given by injection, either subcutaneously or intradermally. The PfSPZ vaccine was developed by Sanaria, Inc. a biotechnology company in Rockville, Md.
The trial, funded primarily by the nonprofit PATH (Program for Appropriate Technology in Health) Malaria Vaccine Initiative, was conducted at the NMRC Clinical Trials Center and at the Center for Vaccine Development, University of Maryland. The biting of immunized volunteers was conducted by collaborators at Walter Reed Army Institute of Research, USMMVP. While most malaria vaccines in clinical development consist of genetically engineered recombinant proteins and viruses that represent small portions of the parasite, this vaccine contains a weakened form of the entire malaria parasite. According to Epstein, the testing of the vaccine by Navy Medicine and their partners opens up a new area of vaccinology.
As reported in Science, scientists from the Vaccine Research Center, National Institute of Allergy and Infectious Diseases (NIAID) National Institutes of Health (NIH) demonstrated in a non-human primate model that when the vaccine was given intravenously, rather than via subcutaneous or intradermal injection, immune responses were extremely impressive. This showed the critical importance of the route of vaccine administration.
Epstein believes these advances in vaccine research are a credit to the dedicated efforts of many military and civilian scientists working in tandem.
"It's all about the partnerships," said Epstein. "The results in this publication reflect the successful collaborative efforts of Navy Medicine and other leading researchers in academia and private industry and demonstrate the immune responses that those involved in the treatment or prevention of malaria have been seeking for decades. The results of the next clinical trial are highly anticipated."
Other members of the research team included Protein Potential LLC, Rockville, Md.; and Howard Hughes Medical Institute, Baltimore, Md.
