Phase 3, Randomized, Safety, Lot Consistency and Clinical Benefit Study of Recombinant Botulinum Vaccine A/B

Currently, there are no licensed vaccines or pre-exposure prophylactic medical
countermeasures available to provide protection against botulism. The rBV A/B is under
development to provide protection of adults 18 to 55 years of age from fatal botulism caused
by inhalational intoxication with botulinum neurotoxin complex (BoNT) serotype A, subtype A1
(BoNT/A1) and botulinum neurotoxin complex serotype B, subtype B1 (BoNT/B1). Volunteers will
not be exposed to botulism. Protective antibody titers will be measured in serum after
vaccination.

Inclusion Criteria:

1. The volunteer is a U.S. citizen or permanent resident alien of the U.S.

2. The volunteer has signed the informed consent form.

3. The volunteer is 18 to 55 years of age.

4. The volunteer agrees not to donate blood or blood product for therapeutic or research
purposes.

5. The volunteer is willing to comply with the requirements of the protocol through the
last scheduled visit.

6. The volunteer is accessible by telephone or electronic mail to receive reminders from
the investigative site.

7. Female volunteers of childbearing potential must not be pregnant or lactating and
agree to use two types of an acceptable form of FDA-approved contraception through
end of study.

8. The volunteer is in good health.

9. The volunteer has clinical laboratory tests within acceptable ranges listed in the
protocol.

Exclusion Criteria:

1. The volunteer has a history of botulism or prior receipt of any botulinum vaccine,
toxoid or antitoxin.

2. The volunteer has previously been treated or expects to be treated with any
therapeutic products containing BoNTs such as Botox®, Myobloc®/Neurobloc™ and Botox®
Cosmetic.

3. The volunteer has a history of hypersensitivity or significant adverse reaction to
other vaccines, aluminum compounds or yeast.

4. The volunteer has a history of severe allergic reactions or anaphylaxis.

5. The volunteer has donated one or more units of blood (≥ 450 mL) or undergone
plasmapheresis within the past 28 days prior to receiving first administration of
study product.

6. The volunteer received any blood product or immunoglobulin in the previous 6 months
prior to receiving first vaccination or plans to receive such products during the
clinical trial.

7. The volunteer received any investigational vaccine in the previous 6 months.

8. The volunteer received or intends to receive any licensed nonliving vaccine within 14
days before or after a scheduled administration of study product.

9. The volunteer received or intends to receive any licensed live vaccine, including
FluMist® within 60 days before or after a scheduled administration of study product.

10. Vaccination with commercially available inactivated or non-living influenza vaccine
preparations (other than FluMist®) if received 14 days before and after a scheduled
administration of study product.

11. The volunteer received any investigational drug therapy within 30 days before the
first vaccination or before the last scheduled visit.

12. The volunteer received therapy with immunosuppressive agents, including use of
moderate to high-dose oral inhaled or systemic corticosteroids (prednisone-equivalent
dose of ≥ 20 mg/day).

13. The volunteer has or develops medically diagnosed chronic migraine headaches
(persistent and recurrent) or a neurological condition associated with a cranial
nerve or spasticity or abnormal muscle contraction, demyelination, other
abnormalities of smooth or skeletal muscle function or hyperhidrosis.

14. The volunteer had systemic or recurrent disease or condition that would place the
volunteer at an unacceptable risk of injury or requires frequent or continuous
medical intervention for treatment, has required hospitalization, or is likely to
require surgical intervention during the course of the study.

15. The volunteer has current active mental illness, history of mental illness or
hospitalization for mental illness within the past 12 months prior to first of
administration of study product is exclusionary.

16. The volunteer has a history of immunodeficiency or autoimmune disease.

17. The volunteer has a systemic medical condition that is ongoing or has required
hospitalization or administration of antimicrobial agents within 6 months before
screening.

18. The volunteer has a history of or active rheumatoid arthritis or any autoimmune
mediated arthritis.

19. The volunteer has an acute self-limited illness that has not resolved by the time of
first vaccination including oral temperature greater than 99.5 °F.

20. The volunteer has a history of abuse of alcohol or drugs within the 12 months before
clinical trial screening.

21. The volunteer has occupational or other responsibilities that would prevent
completion of participation in the clinical trial in the opinion of the Investigator.

22. The volunteer has a body mass index (BMI) ≥ 35 kg/m2.

23. The volunteer is a member of the team conducting this clinical trial or is in a
dependent relationship with the clinical trial investigator.

24. The volunteer has a confirmed positive result on a urine drug screen that tests for
common substances of abuse such as amphetamines, barbiturates, benzodiazepines,
cocaine, opiates and cannabinoids.

25. The volunteer was seropositive on screening tests for human HIV, Hepatitis C virus or
hepatitis B surface antigen.