A Randomized, Double-blind, Placebo-controlled Study to Evaluate the Safety of 3 New 6:2 Influenza Virus Reassortants in Adults

This prospective, randomized, double-blind, placebo-controlled release study will enroll
approximately 300 healthy adults 18 to 49 years of age. Eligible subjects will be randomly
assigned in a 4:1 fashion to receive a single dose of trivalent vaccine or placebo by
intranasal spray. Randomization will be stratified by site. This study will be conducted at
3 sites in the United States of America. Each subject will receive one dose of
investigational product on Study Day 1. The duration of study participation for each subject
is the time from study vaccination through 180 days after study vaccination.

Inclusion Criteria:

1. Age 18 through 49 years

2. Written informed consent

3. Subject available by telephone

4. Ability to understand and comply with the requirements of the protocol, as judged by
the investigator

Exclusion Criteria:

1. Concurrent enrollment in another clinical study up to 180 days after receipt of
investigational product (Day 181)

2. History of hypersensitivity to any component of the vaccine, including egg or egg
protein or serious, life threatening, or severe reactions to previous influenza
vaccinations

3. Any condition for which the inactivated influenza vaccine is indicated, including
chronic disorders of the pulmonary or cardiovascular systems (eg, asthma), chronic
metabolic diseases (eg, diabetes mellitus), renal dysfunction, or hemoglobinopathies
that required regular medical follow-up or hospitalization during the preceding year

4. Acute febrile (> 100.0°F oral or equivalent) and/or clinically significant
respiratory illness (eg, cough or sore throat) within 14 days prior to randomization

5. Any known immunosuppressive condition or immune deficiency disease, including human
immunodeficiency virus infection, or ongoing immunosuppressive therapy

6. History of Guillain-Barré syndrome