A Phase 2 Multi-Center, Randomized Dose-Finding Trial of rPA-102 Vaccine in Healthy Adult Volunteers

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 18-55 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 2 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, or emergency first responders.

- Expected to be noncompliant with study visits or planning to move within 12 months.

- Body mass index of >35 or <19.

- Known allergy to aluminum hydroxide, kanamycin, or any other aminoglycoside
antibiotics (such as gentamicin).

- 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 prior to, and
for the duration of the study.

- Received or plans to receive systemic immunosuppressive therapy, radiation therapy,
or high-dose inhaled steroids within 30 days of study vaccination.

- Use of systemic chemotheraphy 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.