This is a single-center, double-blind, randomized, Phase 1 study to assess the safety and tolerability of HBV-001 D1 in healthy adult subjects.

This is a single-center, double-blind, randomized, Phase 1 study to assess the safety and tolerability of HBV-001 D1 in healthy adult subjects. This will be an upward titration of two dose levels of HBV-001 D1 (10 µg and 50 µg of DEN1-80E) in 16 subjects across two cohorts. Participants in each cohort will receive HBV-001 D1 vaccine or placebo on Visits 1, 3 and 5.

Inclusion Criteria:

• Males or females age 18 to 45.
• Body weight ≥ 110 pounds (50 kg).
• Satisfactory medical condition established by medical history and physical examination.
• Females must be of non-child bearing potential (i.e., surgically sterile) or, if of child-bearing potential must be abstinent or willing to employ adequate means of contraception.

Exclusion Criteria:

• Positive serum test for HIV, Hepatitis B surface antigens (HBsAg) and/or Hepatitis C antibodies.
• Abuse of drugs or alcohol within 12 months prior to screening.
• Use of corticosteroids or immunosuppressive drugs within 30 days of screening (use of topical or nasal corticosteroids is allowed).
• Any confirmed or suspected immunosuppressive or immunodeficient condition.
• Receipt of any vaccination within 30 days prior to screening.
• Receipt of blood products within 6 months of screening.
• Previous flavivirus vaccination (e.g., Japanese encephalitis or yellow fever) or flavivirus vaccination planned during the study period.
• History of flavivirus infection.
• No easy access to a fixed or mobile telephone.
• History of residing in a country endemic for dengue, Japanese encephalitis virus, or Yellow Fever virus for a period of > 1 year.
• Donation of ≥ 450 mL of blood within the previous 12 weeks.