Effect of Gefapixant on Cough-related Brain Activity in Patients With Chronic Cough

• Status: Not yet recruiting
• Trial end date: 2026-06-30
• Target enrollment: 0
• Participant gender: All

Summary

Recently, a new drug called Gefapixant passed phase III clinical trials for cough suppression in patients with chronic cough. The goal of this clinical trial is to investigate the effect of acute and prolonged administration of the drug Gefapixant on cough-related brain activity in patients with chronic cough. The main question it aims to answer is: does the mechanism of action of Gefapixant on the brainstem and brain circuits regulating cough differ between acute and prolonged therapy in people with chronic cough?

Participants have their brain activity and their sensitivity to cough-inducing substances measured as well as complete questionnaires about their cough before and while taking daily Gefapixant.

• Phase: Early Phase 1
• Accepts Healthy Volunteers?: No

Details

• Lead Sponsor: Stuart Mazzone
• Collaborators: Melbourne Health; Merck Sharp & Dohme LLC; Monash University

Criteria

Inclusion Criteria:

• Written informed consent to participate in the study. 18-65 years old; Male or female.

• Non-smokers for at least 5 years and have no history of neurological disease or any recent history (over 8 weeks) of acute respiratory infections.

• Presence of Refractory Chronic Cough (RCC) or Unexplained Chronic Cough (UCC) for ≥1 year, defined as cough unresponsive to treatment for underlying conditions including reflux disease, asthma and rhinitis.

• Presence of cough symptoms as determined by a self-reported cough severity of ≥40mm on 10-point scale on screening.

Exclusion Criteria:

• Current smokers or recreational drug users.

• Women who are pregnant.

• People with contraindications to MRI scanning (i.e. metal implants, claustrophobia).

• Children and/or young people (ie. <18 years).

• People with an intellectual or mental impairment.

• People highly dependent on medical care.

• People in existing dependent or unequal relationships with any member of the research team.

• People with known allergy to chili (very rare).

• Non-English speakers (as English proficiency is required to accurately complete research tasks).