Safety and Immunogenicity of an Inactivated West Nile Virus Vaccine in Healthy Adults

Eligibility Criteria

• 1. Provides written informed consent prior to initiation of any study procedures.
• 2. Is able to understand and agrees to comply with planned study procedures including being available for all study visits.
• 3. Agrees to the collection of venous blood per protocol.
• 4. Is a male or non-pregnant, non-lactating female 18 to 49 years of age, inclusive at time of enrollment.
• 5. Is in good health.\* \*Good health is defined by the absence of a medical condition described in the exclusion criteria. If the participant has another current, ongoing medical condition, the condition cannot meet any of the following criteria: (1) was first diagnosed within 3 months of enrollment with a clinically significant condition, in the opinion of investigator that has worsened within 3 months of enrollment; (2) had non-elective surgery, clinically significant medical procedure, or hospitalization within 3 months of enrollment; (3) received new prescription for systemic medication within 30 days of enrollment, unless the new prescription is in the same class of agent or a transition from generic to/from brand name equivalent; or (4) takes medication that may pose a risk to participant's safety or impede assessment of adverse events or study endpoints if they participate in the study.
• 6. Oral temperature is less than 100.4 degrees Fahrenheit at screening.
• 7. Pulse is 51 to 100 beats per minute, inclusive at screening.
• 8. Systolic blood pressure is 90 to 140 mmHg, inclusive at screening.
• 9. Diastolic blood pressure is 55 to 90 mmHg, inclusive at screening.
• 10. Screening labs must be within acceptable parameters at screening.\*
• 11. Tests for human immunodeficiency virus (HIV) antigens/antibodies, hepatitis B virus (HBV) surface antigen, and hepatitis C virus (HCV) antibodies must be negative at screening.
• 12. Females who are of childbearing potential\* must agree not to become pregnant during trial.
• 13. Females of childbearing potential must agree to use an acceptable contraception method\* from at least 30 days before the first study vaccination and for the duration of the trial.
• 14. Females of childbearing potential must have a negative serum pregnancy test at screening and a negative urine pregnancy test prior to each study vaccination.
• 15. Has body mass index (BMI) 18.5 kg/m\^2 to 34.9 kg/m\^2, inclusive.
• 1. Has an acute illness\* (with or without fever \>/= 38 degrees Celsius \[100.4 degrees Fahrenheit\]) as determined by the PI or appropriate sub-investigator within 72 hours prior to study product administration.
• 2. Has medical disease or condition that, in the opinion of the site PI or appropriate sub-investigator, is a contraindication to study participation.\*
• 3. Received systemic anticancer chemotherapy or radiation therapy (cytotoxic) within 3 years prior to enrollment.
• 4. Has active or recently active (in the 12 months prior to enrollment) neoplastic disease or a history of any hematologic malignancy. Non-melanoma, treated, skin cancers are permitted.
• 5. Has known allergy to components of the study product.\*
• 6. Has history of idiopathic urticaria.
• 7. Has history of chronic or acute severe neurologic condition.\*
• 8. Has history of alcohol or drug abuse within 5 years prior to study vaccination per investigator's discretion.
• 9. Has any diagnosis, current or past, of schizophrenia, bipolar disease or other psychiatric diagnosis that may interfere\* with participant compliance or safety evaluations.
• 10. Has been hospitalized for psychiatric illness, history of suicide attempt, or confinement for danger to self or others within 5 years prior to study vaccination.
• 11. Has moderate to severe asthma.\*
• 12. Has diabetes mellitus type I or II.\*
• 13. Is immunosuppressed.\*
• 14. Have taken high-dose inhaled corticosteroids\* within 30 days prior to study vaccination.
• 15. Received or plan to receive a licensed, live vaccine within 30 days before or after each study vaccination.
• 16. Has received or plans to receive a licensed, inactivated vaccine, including influenza, COVID booster, or allergy desensitization shot, within 14 days before or after study vaccination.
• 17. Received an experimental agent\* within 30 days prior to the study vaccination or expect to receive another experimental agent\*\* during the trial-reporting period.
• 18. Are participating or plan to participate in another clinical trial with an interventional agent\* that will be received during the trial-reporting period.
• 19. Receipt of blood products or immunoglobulin within six months prior enrollment.
• 20. Donation of a unit of blood within 60 days prior to enrollment or intends to donate blood during the study period.
• 21. History of WNV infection or other flavivirus infection (e.g., DENV, ZIKV or other flavivirus).
• 22. History of travel or residency for one month or more in a non-WNV flavivirus-endemic area such as Mexico, Central/South America, the Caribbean, sub-Saharan Africa, South/Southeast Asia, or Polynesia.
• 23. Plans to visit a flavivirus-endemic country during the study trial period (refer to CDC website for areas with active ZIKV, DENV, YFV, or JEV transmission).
• 24. History of vaccination with WNV candidate vaccine.
• 25. History of military service in a flavivirus-endemic region (refer to CDC website for areas with active ZIKV, DENV, YFV, or JEV transmission).
• 26. History of vaccination against YFV, DENV, TBEV, JEV, ZIKV, WNV, or other licensed or investigational flavivirus vaccines or receipt of monoclonal antibodies against a flavivirus.
• 27. Attended primary (grade) school in Austria, Germany, Japan, South Korea, India, Thailand, Nepal, Vietnam, or Taiwan (where TBEV vaccine is given).
• 28. Plan to perform non-routine highly strenuous exercise within 3 days before any clinical safety laboratories.\*
• 29. Has contraindication to intramuscular vaccination of both upper arms.\*
• 30. Has tattoos, scars, or other marks on both upper arms which would, in the opinion of the investigator, interfere with assessment of the vaccination site.