Independent directory Public ClinicalTrials.gov records United States
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ClinicalTrials.gov public records Last synced Sep 28, 2026, 12:47 PM EDT

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Showing 1–4 of 4 matching trials from the live ClinicalTrials.gov search.
Local D1 index available.
Conditions
Chronic Cough
Interventions
Placebo, Gefapixant
Drug
Lead sponsor
Merck Sharp & Dohme LLC
Industry
Eligibility
18 Years and older
Enrollment
732 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2018 – 2020
U.S. locations
27
States / cities
Litchfield Park, Arizona • Scottsdale, Arizona • La Mesa, California + 23 more
Conditions
Healthy
Interventions
Omeprazole, Gefapixant
Drug
Lead sponsor
Afferent Pharmaceuticals, Inc., a subsidiary of Merck & Co., Inc. (Rahway, New Jersey USA)
Industry
Eligibility
18 Years to 55 Years
Enrollment
32 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2016
U.S. locations
1
States / cities
Tempe, Arizona
Completed Phase 2 Interventional Results available

An 8-Week Refractory Chronic Cough Study (MK-7264-021)

NCT02612623
Conditions
Refractory Chronic Cough
Interventions
Gefapixant, Placebo (for gefapixant)
Drug
Lead sponsor
Afferent Pharmaceuticals, Inc., a subsidiary of Merck & Co., Inc. (Rahway, New Jersey USA)
Industry
Eligibility
18 Years to 80 Years
Enrollment
24 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2015 – 2016
U.S. locations
10
States / cities
Mission Viejo, California • San Jose, California • Colorado Springs, Colorado + 7 more
Conditions
Chronic Cough
Interventions
Placebo, Gefapixant 15 mg BID, Gefapixant 45 mg BID
Drug
Lead sponsor
Merck Sharp & Dohme LLC
Industry
Eligibility
18 Years and older
Enrollment
1,317 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2018 – 2020
U.S. locations
34
States / cities
Peoria, Arizona • Phoenix, Arizona • Tempe, Arizona + 31 more