Trial to Evaluate the Safety and Immunogenicity of an Anthrax Recombinant Protective Antigen Vaccine

Inclusion Criteria: Able to understand the study and give written informed consent. A signed informed consent must be in place before the initiation of any study interventions. Healthy male or female aged 18 to 40 years old (inclusive) without significant physical or clinical laboratory abnormalities. Two intact upper arms with sufficient intramuscular (IM) tissue in the deltoid region for vaccine administration. For females, negative serum pregnancy test at screening and agreement to use adequate birth control during the first 3 months of the study. Willingness and ability to return for all follow-up visits and blood draws for the duration of the study. Willingness to complete the Volunteer Diary and to report concomitant medications and adverse events (AEs) to the study site monitors during the study period. Exclusion Criteria: Prior history of, or known exposure to any form of B. anthracis or any anthrax immunization. Member of the Armed Services (Active Duty or Reserve) since 1990, with history of previous anthrax vaccination. Employment in an industry involved in contact with ruminant animals, veterinary sciences, or other exposure to B. anthracis. Expected to be noncompliant with study visits or planning to move within 8 months. Body mass index of >35 or <19. Known allergy to aluminum hydroxide, formaldehyde, benzethonium chloride, latex, kanamycin, or any other aminoglycoside antibiotics (such as gentamycin). Pregnancy (positive urine pregnancy test within 24 hours prior to vaccination), or lactation. HIV positive (by history or screening ELISA). Hepatitis B or C positive (by history or screening HBsAg/anti-HCV ELISA). Active or past internal organ, hematologic malignancy, or metastatic cutaneous malignancy. History of, or current autoimmune disease, including but not limited to systemic lupus erythematosus, scleroderma, and polyarteritis. Immunodeficiency or unstable medical condition as determined by baseline medical history, physical exam, and laboratory assessment. Received, or plans to receive, licensed live vaccines within 30 days of study vaccination. Received, or plans to receive, licensed killed vaccines within 14 days of study vaccination. Received, or plans to receive, immunoglobulin or other blood products within 60 days of study vaccination. Received, or plans to receive, experimental drugs/vaccines within 30 days of study vaccination. Received, or plans to receive, systemic immunosuppresive therapy, radiation therapy, or high-dose inhaled steroids within 30 days of study vaccination. Use of systemic chemotherapy within 5 years prior to study. History of Guillain-Barre Syndrome. In addition to the conditions listed above, the following may qualify as a reason to exclude a volunteer from the study: fever along with moderate or serious illness within 3 days of vaccination or any condition that, in the opinion of the investigator, would render vaccination unsafe or would interfere with the study evaluations. Pending resolution of these symptoms, a volunteer may be reconsidered for vaccination.