Conditions: Refractory Chronic Cough
Allocation: RANDOMIZED | Intervention model: PARALLEL
Enrollment: 253
Healthy volunteers: no

Brief summary:
This study is designed to evaluate the efficacy of three dose regimens of gefapixant (\[MK-7264\] 7.5 mg, 20 mg, and 50 mg) relative to placebo in reducing awake objective cough frequency. The primary hypothesis for this trial is that at least one dose regimen of gefapixant is superior to placebo with respect to the mean change from baseline in awake cough frequency (on the log scale).

Detailed description:

Arms:
arm 1: Participants received one matching placebo tablet administered by mouth twice daily for 12 weeks. arm 2: Participants received one 7.5 mg gefapixant tablet administered by mouth twice daily for 12 weeks. arm 3: Participants received one 20 mg gefapixant tablet administered by mouth twice daily for 12 weeks. arm 4: Participants received one 50 mg gefapixant tablet administered by mouth twice daily for 12 weeks.

Interventions: intervention 1: Gefapixant intervention 2: Placebo (for gefapixant)
Intervention descriptions: intervention 1: Gefapixant administered as one 7.5 mg, 20 mg, or 50 mg tablet twice daily, depending upon randomization. intervention 2: None

Protocol document: