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

Inclusion 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 includingbeing 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 attime of enrollment.

5. Is in good health.* *Good health is defined by the absence of a medical conditiondescribed in the exclusion criteria. If the participant has another current, ongoingmedical condition, the condition cannot meet any of the following criteria: (1) wasfirst diagnosed within 3 months of enrollment with a clinically significantcondition, in the opinion of investigator that has worsened within 3 months ofenrollment; (2) had non-elective surgery, clinically significant medical procedure,or hospitalization within 3 months of enrollment; (3) received new prescription forsystemic medication within 30 days of enrollment, unless the new prescription is inthe 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 impedeassessment 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.*

*Hematology (white blood cell count [WBC], hemoglobin and platelet count), serumcreatinine, and liver panel (ALT, AST, and total bilirubin) should fall within thenormal range of the clinical reference lab. A low creatinine value, low totalbilirubin, or a low ALT value are acceptable for trial inclusion as they are notconsidered to be clinically significant. If screening lab values are within thenormal range of the clinical reference lab but fall within the Grade 1 FDA toxicitytable range, these will be considered acceptable for enrollment. Urine glucose mustbe negative and urine protein <1+ (trace urine protein is acceptable) at screeningto be eligible for the study. Abnormal urine protein in females on their menses canbe repeated after menses is finished.

11. Tests for human immunodeficiency virus (HIV) antigens/antibodies, hepatitis B virus (HBV) surface antigen, and hepatitis C virus (HCV) antibodies must be negative atscreening.

12. Females who are of childbearing potential* must agree not to become pregnant duringtrial.

*Not of childbearing potential includes post-menopausal females (defined as nomenses for at least 12 consecutive months without an alternative medical cause foramenorrhea), or surgically sterile females with documented per volunteer reporthistory of hysterectomy, bilateral oophorectomy, tubal ligation/salpingectomy, orEssure(R) placement and at least 3 months have passed since sterilization procedure.

13. Females of childbearing potential must agree to use an acceptable contraceptionmethod* from at least 30 days before the first study vaccination and for theduration of the trial.

*Acceptable forms of contraception include monogamous relationship with avasectomized male partner who has been vasectomized for 90 days or more prior toenrollment, use of intrauterine devices, birth control pills, hormonal birth controlproducts that are injectable, implantable (subdermal), transdermal or insertable (vaginal ring), barrier methods with spermicide. Females of childbearing potentialwho practice abstinence (defined as no heterosexual vaginal-penile intercourse) andagree to practice abstinence consistently for the duration of the study or those whohave exclusively non-male sexual relations do not need to use contraception.

14. Females of childbearing potential must have a negative serum pregnancy test atscreening 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.

Exclusion Criteria:

1. Has an acute illness* (with or without fever >/= 38 degrees Celsius [100.4 degreesFahrenheit]) as determined by the PI or appropriate sub-investigator within 72 hoursprior to study product administration.

*Participants who are afebrile (if applicable) and have either no symptoms or onlyminor residual symptoms in the 72 hours prior to study product administration can beenrolled if, in the opinion of the site PI or appropriate sub-investigator, theresidual symptoms will not interfere with the ability to assess safety parameters asrequired by the protocol.

2. Has medical disease or condition that, in the opinion of the site PI or appropriatesub-investigator, is a contraindication to study participation.*

*Including acute, subacute, intermittent, or chronic medical disease or conditionthat would place the participant an unacceptable risk of injury, render theparticipant unable to meet the requirements of the protocol, or may interfere withthe evaluation of responses or the participant's successful completion of thistrial.

3. Received systemic anticancer chemotherapy or radiation therapy (cytotoxic) within 3years prior to enrollment.

4. Has active or recently active (in the 12 months prior to enrollment) neoplasticdisease or a history of any hematologic malignancy. Non-melanoma, treated, skincancers are permitted.

5. Has known allergy to components of the study product.*

*Including the following: aluminum hydroxide, sorbitol, potassium chloride, sodiumchloride and polysorbate80 (Tween80).

6. Has history of idiopathic urticaria.

7. Has history of chronic or acute severe neurologic condition.*

*Including history of Guillain-Barre syndrome, seizure disorder or epilepsy, Bell'spalsy, or disease with any focal neurologic deficits.

8. Has history of alcohol or drug abuse within 5 years prior to study vaccination perinvestigator's discretion.

9. Has any diagnosis, current or past, of schizophrenia, bipolar disease or otherpsychiatric diagnosis that may interfere* with participant compliance or safetyevaluations.

*As determined by the site PI or appropriate sub-investigator.

10. Has been hospitalized for psychiatric illness, history of suicide attempt, orconfinement for danger to self or others within 5 years prior to study vaccination.

11. Has moderate to severe asthma.*

*Mild, well-controlled asthma may qualify for enrollment as determined by the sitePI or appropriate sub-investigator. Cold or exercise induced asthma controlled withinhaled medications other than high - dose inhaled corticosteroids within the past 30 days is permissible. Participants should be excluded if they require dailybronchodilator use or have had an asthma exacerbation requiring oral/parenteralsteroid use within the past 30 days or have used theophylline in the past year.

12. Has diabetes mellitus type I or II.*

*History of gestational diabetes if resolved is acceptable.

13. Is immunosuppressed.*

*Due to an underlying condition, taking immunomodulatory treatment, or took oral orparenteral (including intra-articular) corticosteroids within the past 30 days or >/= 2 weeks topical corticosteroids of any dose within 30 days prior to studyvaccination. Corticosteroid nasal sprays for allergic rhinitis are permissible.Persons using a topical corticosteroid for a limited duration for mild uncomplicateddermatitis such as poison ivy or contact dermatitis may be enrolled the day aftertheir therapy is completed.

14. Have taken high-dose inhaled corticosteroids* within 30 days prior to studyvaccination.

*High-dose defined per reference chart in the National Heart, Lung and BloodInstitute Guidelines for the Diagnosis and Management of Asthma (EPR-3).

15. Received or plan to receive a licensed, live vaccine within 30 days before or aftereach study vaccination.

16. Has received or plans to receive a licensed, inactivated vaccine, includinginfluenza, COVID booster, or allergy desensitization shot, within 14 days before orafter study vaccination.

17. Received an experimental agent* within 30 days prior to the study vaccination orexpect to receive another experimental agent** during the trial-reporting period.

*Including vaccine, drug, biologic, device, blood product, or medication.

**Other than from participation in this trial.

18. Are participating or plan to participate in another clinical trial with aninterventional agent* that will be received during the trial-reporting period.

*Including licensed or unlicensed vaccine, drug, biologic, device, blood product, ormedication.

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 donateblood during the study period.

21. History of WNV infection or other flavivirus infection (e.g., DENV, ZIKV or otherflavivirus).

22. History of travel or residency for one month or more in a non-WNV flavivirus-endemicarea 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 toCDC 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 forareas with active ZIKV, DENV, YFV, or JEV transmission).

26. History of vaccination against YFV, DENV, TBEV, JEV, ZIKV, WNV, or other licensed orinvestigational flavivirus vaccines or receipt of monoclonal antibodies against aflavivirus.

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 anyclinical safety laboratories.*

*Safety laboratories are obtained on day of vaccination prior to dosing (i.e. Visit 01, Visit 05, and Visit 11) and Day 15 following each dose of study product (i.e.Visit 04, Visit 08 and Visit 14).

29. Has contraindication to intramuscular vaccination of both upper arms.*

*Patient with low platelet count or coagulopathy, or someone who is taking oralanticoagulants.

30. Has tattoos, scars, or other marks on both upper arms which would, in the opinion ofthe investigator, interfere with assessment of the vaccination site.