DESCRIPTION (provided by applicant): Anthrax, an infectious disease caused by Bacillus anthracis, became a pressing concern because of its potential biowarfare use, most likely via aerosolized anthrax spore dissemination, resulting in deadly inhalation anthrax. The current vaccine, which confers protection by inducing antibodies against anthrax toxin, has significant drawbacks including limited availability, lack of standardization and quality control, the need for repeated injections, and frequent occurrence of side effects, making it inadequate for use in large populations. A new vaccine is urgently needed. A DNA vaccine directed against anthrax toxin would be economical, relatively easy to prepare, store and standardize, should induce few, if any, side effects. It would also permit the inclusion of several clearly defined antigens. The method of application of a DNA vaccine is critical for efficacy. Vaccine will be delivered by electroporation because this method provides consistent, high level, scalable immunogen expression, which correlates with high magnitude, durable antibody responses. Dosing protocols will be precisely defined in rats. Protocols will be scaled-up in rabbits using a proprietary scaling algorithm. Readouts will include toxin-neutralizing antibody titers, which are considered a correlate for immunity. Protocols inducing high-magnitude, functional immunity will be tested in rabbit for protection against inhalation challenge.