Safety, Tolerability, and Immunogenicity of VAL-339851 in Healthy Adult Subjects

Inclusion Criteria:

- Agrees to comply with the study procedures and provides written informed consent

- 18 to 49 years of age

- Body mass index between 18 and 35 kg/m2

- Negative urine pregnancy test at the Screening visit and the day of each vaccination
for females of childbearing potential.

- Female subjects must either be of non-childbearing potential or use acceptable methods
of contraception from at least 3 weeks prior to enrollment and through the end of
study visit

- In good health based on medical history, physical examination, vital sign measurements
and laboratory safety tests performed prior to initial study vaccination

- Has access to a consistent and reliable means of telephone contact and agrees to stay
in contact with the study site for the duration of the study

Exclusion Criteria:

- Any ongoing, symptomatic acute or chronic illness requiring medical or surgical care

- Administration of another investigational product within 60 days, or 5 half-lives,
whichever is longer

- Participation in an investigational study involving lipid nanoparticles

- A history of hypersensitivity or serious reactions to previous influenza vaccinations

- History of Guillain-Barré Syndrome within 6 weeks following a previous influenza
vaccine

- History of narcolepsy

- Administration of any licensed (inactivated or live) vaccines within 4 weeks before
enrollment or plans to receive any vaccine within 12 weeks of the last study drug
administration; receipt of any other avian H7N9 influenza vaccine at any time prior to
or during the study is exclusionary

- Any known or suspected immunosuppressive condition, acquired or congenital, as
determined by history and/or physical examination.

- Any chronic administration of immunosuppressant or other immune-modifying drugs within
6 months prior to administration of study vaccine

- Administration of immunoglobulins and/or any blood products within the 3 months
preceding the administration of the study vaccine or during the study.

- Any acute disease at the time of enrollment

- Any significant disorder of coagulation requiring ongoing or intermittent treatment

- Active neoplastic disease or a history of any hematologic malignancy

- History of alcohol abuse or drug addiction within 1 year before the planned day of
dose administration

- A positive test result for drugs of abuse or alcohol at screening or before the first
dose administration

- Persons employed in a capacity that involves handling poultry or wild birds.

- The subject has any abnormality or permanent body art (eg, tattoo) that, in the
opinion of the investigator, would obstruct the ability to observe local reactions at
the injection site

- Any condition, that in the opinion of the Investigator would pose a health risk to the
subject if enrolled or could interfere with evaluation of the vaccine or
interpretation of the study results

- A positive test result for hepatitis B surface antigen, hepatitis C virus antibody, or
human immunodeficiency virus types 1 or 2 antibodies at screening

- Donation of blood or blood products > 450 mL within 30 days of dosing