Pharmacodynamic Open-Label Trial With VXA-A1.1 Oral H1 Vaccine in Healthy Adults

This is a pharmacodynamics study in healthy adult males. The purpose of the study is to
determine if the tablet formulation size of VXA-A1.1, an adjuvanted adenoviral based
influenza vaccine, impacts the location and time of initial and complete disintegration of
the drug product. The secondary objective is to evaluate delivery with fasting versus fed
status.

Inclusion Criteria:

- Male volunteers aged 18 - 49 years, inclusive

- Willing and able to give written informed consent/HIPAA authorization form

- In good health (no clinically significant health concerns), as determined by medical
history, physical examination, 12-lead ECG, vital signs and laboratory tests at
screening

- Liver function tests (alanine aminotransferase (ALT), aspartate amino transferase
(AST), alkaline phosphatase (ALP), direct bilirubin (DB) and total bilirubin (TB) are
within the normal range. [N.B., an elevated TB in the absence of an elevated direct
bilirubin (benign unconjugated hyperbilirubinemia, known as Gilbert's Syndrome) will
not be exclusionary]

- Body weight ≥ 50 kg and a Body mass index between 17 and 35 at screening

- Willingness to abstain from caffeine or xanthine containing foods or beverages,
alcohol, tobacco or nicotine-containing products and strenuous exercise from 72 hours
prior to screening and each dosing until discharge post each Dosing Day.

- Dietary habits that fall within the range of normal, as determined by the
Investigator. Examples of abnormal diets are liquid diets, protein only diets, high
fat diets, or low carbohydrate diets.

- Verbal confirmation from subject that his bowel movements are regular.

- Comprehension of the study requirements (in English) with ability and willingness to
complete all assessments and comply with scheduled visits and contacts.

Exclusion Criteria:

- Administration of any vaccine within 4 weeks preceding DP administration or during the
study through the active period (Day 36), or any licensed or investigational
adjuvanted vaccine within 12 months preceding DP administration, or planned use of any
licensed or investigational adjuvanted vaccine during the study through the 12-month
safety follow- up period

- Use of any investigational drug or device the greater of: within 4 weeks preceding DP
administration, or planned use of the above stated during the study through the study
active period (Day 36) OR within 5 half-lives of an investigational drug product

- Use of concomitant medications that may interfere with normal gastrointestinal tract
function, including but not limited to those listed below:

1. Proton pump inhibitors

2. H2 blockers

3. GI motility stimulants (e.g. metoclopramide)

4. Anti-nausea/anti-emetics

5. Opiate class pain relievers

6. Anti-diarrheals

7. Laxatives

- Presence of significant uncontrolled medical or psychiatric illness (acute or chronic)
including institution of new medical/surgical treatment or significant dose alteration
for uncontrolled symptoms or drug toxicity within 3 months of screening

- Any one of the following ECG findings within 30 days prior to administration:

1. QTc F (interval duration > 450 msec (male),

2. QRS interval greater than 120 msec,

3. PR interval greater than 220 msec,

4. Clinically significant ST-T wave changes or pathologic Q waves

- Positive serology for HIV-1 or HIV-2, or HBsAg or HCV antibodies

- Cancer, or treatment for cancer, within past 3 years (excluding basal cell carcinoma,
squamous cell carcinoma, and cervical cancer in situ)

- Radiation exposure from clinical trials, including that from the present study, and
from diagnostic X-rays, but excluding background radiation, exceeding a target organ
(colon) dose of 50 mSv (5 rems) from a single dose within the last 30 days or a
cumulative dose of 150 mSv (15 rems) in the last 12 months. No subject whose
occupation requires monitoring for radiation exposure may be enrolled in the study.

- Presence of household members who are neonates, pregnant women, or hematopoietic stem
cell transplant or solid organ transplant recipients or who are immunocompromised
including those who are HIV positive.

- History of drug, alcohol or chemical abuse within 1 year prior to administration

- Acute disease within 72 hours prior to administration defined as the presence of a
moderate or severe illness with or without fever (as determined by the Investigator
through medical history and physical examination) or any acute respiratory or
gastrointestinal illness even with mild symptoms occurring within 7 days of
administration

- Presence of a fever ≥ 38ºC measured orally at baseline

- Positive urine drug screen for drugs of abuse at screening

- Positive breath or urine alcohol test at screening

- Consistent/habitual smoking (> 10 cigarettes/day) within 6 months prior to
administration

- History or presence of acute/chronic diarrhea or constipation

- History of serious reactions to any vaccination such as anaphylaxis, respiratory
problems, Guillain-Barre syndrome, hives or abdominal pain

- History of a hypersensitivity or allergic reaction to any component of the
investigational DP, including but not limited to fish gelatin

- History of irritable bowel disease or inflammatory digestive or gastrointestinal
condition that could affect the distribution / safety evaluation of an orally
administered DP targeting the mucosa of the small intestine. Such conditions may
include but are not limited to:

1. Esophageal Motility Disorder

2. Malignancy

3. Malabsorption

4. Pancreaticobiliary disorders

5. Irritable bowel syndrome

6. Celiac Disease

7. Inflammatory Bowel Disease

8. Surgical Resection with the exception of appendectomy or a minor resection that
is deemed acceptable by investigator and sponsor

9. GERD

10. Hiatal Hernia

11. Peptic Ulcer (History of cholecystectomy is not exclusionary)

- Any condition that resulted in the absence or removal of the spleen

- History of any form of angioedema

- Male subject who is unwilling to use an acceptable method of contraception, as listed
below, for the duration of the study and continuing for 90 days after the subject's
last study DP dose. Acceptable methods of contraception include the following: (1)
complete abstinence from intercourse beginning with the first dose of study DP and
continuing for 90 days after the final study DP dose, (2) male subject sterilization
(vasectomy), (3) sterilization of or non-childbearing potential female partner
(bilateral tubal ligation/salpingectomy, hysterectomy, post-menopausal), (4) use of
hormonal contraception by female partner (implantable, patch, oral, injectable), (5)
use of an intrauterine device (IUD) or intrauterine system by female partner, (6)
barrier methods (condom by male or an occlusive cap [diaphragm or cervical/vault caps]
by female partner) with concomitant spermicidal foam/gel/film/cream/suppository use,
(7) any other birth control method with published data showing a failure rate that is
< 1% per year. Male subjects should not donate sperm for the duration of the study and
for 90 days after the last DP dose. Male subjects who are not sexually active but
become active, must comply with the contraceptive requirements above.

- Any condition that, in the opinion of the Investigator, might interfere with ability
to assess the primary study objectives