Saint Louis University studies experimental anthrax vaccines

Saint Louis University's (SLU) Center for Vaccine Development is investigating two experimental anthrax vaccines to compare the safety and ability of the vaccines to trigger an immune response against the bioterror threat.

The two experimental anthrax vaccines, which are manufactured by PaxVax, are comprised of an adenovirus that contains protective antigen (PA). PA is an inactive part of the anthrax toxin that may trigger the production of antibodies against anthrax. Approximately 30 volunteers at SLU will be administered the vaccines as part of a Phase I study.

"This research is being done to increase our knowledge and our ability to respond to anthrax attacks if they were to occur in the future," Geoffrey Gorse, the principal investigator for the study, said. "The distribution of anthrax spores in the U.S. mail highlighted the urgent need for vaccines to respond to the terrorist threat of biological warfare and, in particular, satisfactory preventive measures for anthrax exposure."

The experimental vaccines use the same protective antigen that is in the currently licensed injected anthrax vaccine, but the PaxVax vaccines come in the form of a swallowed vaccine pill.

Scientists will compare the safety and ability of the two experimental swallowed anthrax vaccine pills to determine if they trigger an immune response in healthy men and women between the ages of 18 and 40 years old. The researchers will also investigate dosages, timing intervals and transmissibility of the adenovirus.

PaxVax has a contract with the National Institute of Allergy and Infectious Diseases to investigate the experimental anthrax vaccines.