Nasal Residency of HEX17

This Phase 1 study will evaluate HEX17, an investigational antiviral nasal spray, in healthy adult volunteers. The study has two parts. Part A will validate a laboratory method called fluorescence activated cell sorting (FACS) to detect HEX17 bound to nasal epithelial cells after a single intranasal dose. Part B will investigate how long HEX17 remains present in nasal epithelial cells following five different dosing regimens. The study will also assess the safety and tolerability of HEX17 following intranasal administration in healthy adult participants.