Safety and Immunogenicity Study of the Hepatitis B Virus (HBV) Vaccine, HEPLISAV Compared to Engerix-B Vaccine

The purpose of the study is to evaluate the safety, immunogenicity and lot-to-lot consistency
of an investigational hepatitis B virus vaccine, HEPLISAV™, in healthy adults 40 to 70 years
of age

Inclusion Criteria:

- be 40 - 70 years of age, inclusive

- be seronegative for hepatitis B surface antigen (HBsAg), antibody against hepatitis B
surface antigen (anti-HBsAg), antibody against hepatitis B core antigen (anti-HBcAg),
and human immunodeficiency virus (HIV)

- be in good health in the opinion of the investigator, based upon medical history,
physical examination, and laboratory evaluation

- if female of childbearing potential, agree to consistently use a highly effective
method of birth control from screening visit through the treatment phase, for up to 28
days after the last injection

Exclusion Criteria:

- if female of childbearing potential, is pregnant, breastfeeding, or planning a
pregnancy

- has a history of or is considered by the investigator to be at high risk for recent
exposure to HBV or HIV; for example, current intravenous drug use or has unprotected
sex with known HBV/HIV positive partner

- has a known history of autoimmune disease

- has previously received any hepatitis B vaccine (approved or investigational)