After being informed about the study and potential risks, all healthy volunteers that have given written informed consent will undergo screening to determine eligibility for study entry. If the healthy volunteer qualifies for the study, they will be randomly assigned to 1 of 3 treatment groups. Within the treatment group, the participant will be randomized in a double-blind manner in a 5:2 ratio to NasoShield or placebo.

The investigational drug (either NasoShield or placebo) will be administered on Days 1 and 29 after qualifying into the study. The position of administration and the amount of time the subject will need to stay in the specified position will depend on the group to which the subject is assigned.

Participants will return to the investigational site for multiple visits through Day 210 (approximately 6 months after the second dose). At each visit, the participant will be asked about interim medical history and use of any medications, and safety and immunogenicity assessments will be performed.