Subjects will be screened within 28 days of randomization (Day 1). Approximately 60 subjects who meet all inclusion and no exclusion criteria and provide written informed consent will be enrolled into 3 sequential cohorts of 20 subjects each defined by the viral particle dose (1×10(9th), 1×10(10th), and 1×10(11th) vp).

Within each cohort and its sentinel group, subjects will be randomized in a 3:1 ratio to receive 1 intranasal dose of NasoVAX or placebo (Day 1). A sentinel group of 5 subjects from each cohort will be dosed and followed through Day 8. Dosing of the remainder of each cohort may proceed if no events meeting stopping criteria have occurred.

The SRC, consisting of the Investigator, the Medical Monitor, and a Sponsor Representative, will review AE, reactogenicity, and laboratory data through Day 8 for all subjects in each cohort before subjects are randomized to the next higher dose. If any event meeting stopping criteria occur, the SRC will review all available safety information before additional patients are dosed.