Safety and Immunogenicity of ChimeriVax-WN02 West Nile Vaccine in Healthy Adults

Inclusion Criteria: Part 1

• Healthy adult aged 18 to 40 years.
• Women of child-bearing potential should be using hormonal contraception.
• Subject had to be available for the study duration, including all planned follow-up visits.

Exclusion Criteria: Part 1

• Previous vaccination against yellow fever or Japanese encephalitis
• History of flavivirus infection
• Any abnormalities of immune system, or using drugs that affect the immune system.
• History of anaphylaxis to foods, bee stings, vaccines or drugs.
• Receipt of blood or blood products within the preceding 6 months.
• Receipt of any vaccine in the preceding 30 days
• Seropositive to hepatitis C virus (HCV), hepatitis B surface antigen (HBsAg) or Human immunodeficiency virus (HIV)
• Lactation or intended pregnancy in female subjects
• Previous or current military service with overseas deployment
• Travel to Mexico or other flavivirus endemic areas in the tropics for periods of four weeks or more in the previous ten years.

Inclusion Criteria: Part 2

• Aged ≥ 41 years.
• Subjects had to be in general good health.
• Unimpaired cognitive performance as assessed by clock drawing test score
• Subject had to be available for all required study visits, including all planned follow-up visits.
• Women of child-bearing potential should be using hormonal contraception.

Exclusion Criteria: Part 2

• Clinically significant abnormalities on the Screening 12-lead electrocardiogram (ECG).
• An acute or chronic medical condition that, in the opinion of the Investigator, would render vaccination unsafe or would interfere with the evaluation of responses. These conditions included, but were not limited to:
• History of renal impairment
• History of significant liver disease or hepatic impairment
• History of diabetes mellitus (except controlled with diet)
• An arteriosclerotic event during the 6 months prior to enrollment (including but not limited to myocardial infarction or unstable angina, peripheral bypass surgery for revascularization of an extremity, and transient ischemic attack or stroke)
• Signs of congestive heart failure at the time of enrollment
• Angina
• Subjects with 3 or more of the following:
• Age over 50 years
• Hypercholesterolemia, or significantly abnormal lipid profile, based on medical history
• Any prior history of cardiovascular disease
• Significant family history of cardiovascular disease in any immediate relative
• History of significant collagen vascular disease.
• The unexplained presence of any of the following findings:
• Any significant episodes of confusion, memory loss, language impairment, other cognitive impairment, or other abnormal behavior if relatively abrupt in onset
• Clinically significant depression
• Sudden visual impairment (e.g., loss of vision, double vision)
• Slurred or abnormal speech
• Sudden onset of vertigo
• Focal weakness in any extremity
• Focal sensory loss in any extremity
• Impaired balance
• Impaired gait.
• Subjects with any diagnosis of dementia or associated concomitant medications (e.g., Aricept) used for treating dementia.
• Subjects with active or a history of neurologic disease or injury, including, but not limited to: Parkinson's, Guillain Barre, epilepsy (except febrile seizures in youth not treated with medication), cerebrovascular accident, head trauma, or any other neurologic condition thought to impact the integrity of the blood-brain barrier.
• Subjects taking warfarin, heparin, or with known bleeding disorders.
• Relative or employee of the study site staff, CRO, or Sponsor participating in this trial.
• A history of vaccination against yellow fever (YF) or Japanese encephalitis. Previous vaccination was determined by history (interview of subject) and/or by reviewing the subject's vaccination card or other official documentation.
• History of flavivirus infection (e.g. West Nile [WN], Systemic Lupus Erythematosus [SLE], Japanese encephalitis, dengue fever).
• History of thymoma, thymic surgery (removal)