A Navy-led team of researchers has successfully tested a DNA vaccine in healthy humans, a significant milestone in medicine's fight against many deadly diseases. While DNA vaccines showed impressive results in previous animal studies, this malaria DNA vaccine is the first to be successful in healthy humans.
DNA vaccines have the potential to prevent a wide variety of the most common infectious diseases, such as malaria, AIDS, dengue fever, and tuberculosis; highly fatal diseases, such as Ebola and Lassa fever; biological warfare threats; and cancer.
The team, headed by Navy Capt. Stephen Hoffman, a physician, is based at the Naval Medical Research Center in Bethesda, Md. An article about Hoffman's study is in the Oct. 16 issue of Science magazine.
"The purpose of this study was to determine if DNA immunization is safe, well-tolerated and generates an immune response in normal humans," said Hoffman. "We established this, so our next step is to develop a vaccine that will provide protection."
Hoffman and researchers from Vical, Inc., the U.S. Army Medical Research Institute of Infectious Diseases and Pasteur Merieux Connaught (Rhone-Poulenc Group) immunized 20 healthy human volunteers with a malaria DNA vaccine. The majority developed potent "killer" T-cells, which defend the human body against the disease.
"We used malaria as a model system to test this exciting new technology because it is the most important infectious disease threat to our operating forces," said Hoffman. "The significance of this demonstration, however, is in the proof of principle that allows us to advance toward a new era in vaccines."
The Naval Medical Research Center began researching DNA vaccines more than six years ago as part of their mission to combat health threats to military members. One of the major threats to the American military forces is malaria, which threatens billions and afflicts 300 to 500 million individuals worldwide each year.
While licensing of a DNA vaccine for any disease is still years away, this is a major step forward.
According to many experts, including Sir Gustav Nossal, the chairman of the Children's Vaccine Initiative Scientific Advisory Group of Experts, this next generation vaccine may revolutionize immunization.
"DNA vaccines have made their explosive entry (into medicine), possibly signaling a revolution in vaccinology based on their ease of production, stability, and simplicity of combination," wrote Sir Gustav in Nature Medicine Vaccine Supplement.
The Navy has collaborated for five years with Vical, Inc., a San Diego biotech company that discovered and patented the new vaccine technology. Support for the project came from DOD's Military Infectious Diseases Research Program, the Federal Defense Laboratories Diversification Program, the Office of Naval Research's Advanced Technology Demonstration Program, and the pharmaceutical company Pasteur Merieux Connaught.
In addition to Hoffman, the team includes Drs. Ruobing Wang, Denise L. Doolan, Jennifer Ng, Martha Sedegah, and Yupin Charoenvit; Navy Cmdrs. Richard C. Hedstrom, Thong P. Le, Walter Weiss, and Trevor Jones; Drs. Jon Norman, Peter Hobart, and Michal Margalith of Vical, Inc.; Army Capt. Kevin Coonan of the U.S. Army Medical Research Institute of Infectious Diseases; and Charles De Taisne of Pasteur Merieux Connaught.
For more information, contact Lt. Jensin Sommer and Ms. Doris Ryan at the Navy's Bureau of Medicine and Surgery, (202) 762-3222.