The purpose of this study is to assess the safety, tolerability, and pharmacokinetics (PK) effects of GSK2339345 in healthy subjects. GSK2339345 is a blocker of neuronal voltage gated sodium channels in development for the treatment of chronic cough, excessive cough and post-viral and viral (acute) cough. Inhaled pan NaV inhibitors are associated with oropharyngeal sensation perturbation and so this study will establish the potential local sensate effects of GSK2339345 at multiples of the predicted inhaled therapeutic dose. This study also aims to define the maximum tolerated dose of GSK2339345 administered via an aqueous droplet inhaler. Cohort 1 is a randomised, double-blind, placebo-controlled, cross-over, inhaled single-dose escalating study using an aqueous droplet inhaler. Cohort 1 will include assessments of sensate changes via a 4 point scale, assessment of taste via an 11 point scale, and PK assessments to investigate the PK profile of GSK2339345. Cohort 2 of this study is a randomised, double blind, placebo controlled, parallel group, inhaled repeat dose study using a aqueous droplet inhaler. Subjects will be randomised to receive 2000 microgram of GSK2339345 or placebo four times a day for two consecutive study days. Similar assessments of sensations to those used in Cohort 1 will be performed. The potential for systemic cardiovascular (CV) or central nervous system (CNS) effects will also be assessed throughout the study via observation. Cohort 2 will also include PK assessments to investigate the PK profile of GSK2339345. Placebo will be used throughout the study as a control.
This is a study of the sodium channel inhibitor, GSK2339345. Cohort 1 will assess the safety, tolerability and PK of single ascending doses of GSK2339345 administered via an aqueous droplet inhaler in healthy subjects. Cohort 2 will assess the safety, tolerability, and PK of repeat doses of GSK2339345 administered four times a day for two consecutive days via an aqueous droplet inhaler.