Efficacy and Safety of Gefapixant (MK-7264) in Adult Participants With Recent Onset Chronic Cough (MK-7264-043)
Condition: Chronic Cough
MeSH terms: Cough
Intervention: Gefapixant; Placebo
Intervention description: Administered twice daily as an oral tablet of 45 mg; Administered twice daily as a placebo oral tablet matching gefapixant
Phase: Phase 3
Study type: Interventional
Primary purpose: Treatment
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Enrollment: 419.0
Sex: All
Minimum age: 18 Years
Healthy volunteers: No
Keywords: Cough; Respiration disorders; Respiratory tract diseases; Signs and symptoms, respiratory; Signs and symptoms

Summary:

      The purpose of this study is to evaluate the efficacy and safety of gefapixant in
      participants with recent onset chronic cough (duration >8 weeks after onset of cough
      symptoms) for <12 months and a diagnosis of refractory or unexplained chronic cough. The
      primary hypothesis is that gefapixant is superior to placebo in improving cough-related
      quality of life measured as change from baseline in the Leicester Cough Questionnaire (LCQ)
      total score at Week 12.
    

Eligibility criteria:

        Inclusion Criteria:

          -  Chest radiograph or CT thorax (within 1 year of Screening/Visit 1 and after the onset
             of chronic cough) not demonstrating any abnormality considered to be significantly
             contributing to the chronic cough or any other clinically significant lung disease, in
             the opinion of the principal investigator or the subinvestigator

          -  Has chronic cough (defined as duration of >8 weeks after onset of cough symptoms) for
             <12 months prior to the screening visit (<14 months after onset of cough symptoms)

          -  Has a diagnosis of refractory chronic cough or unexplained chronic cough

          -  Female participants are not pregnant, not breastfeeding, not of childbearing
             potential, or agree to follow contraceptive guidance

        Exclusion Criteria:

          -  Is a current smoker

          -  Has given up smoking within 12 months of screening

          -  Is a former smoker with a smoking history greater than 20 pack-years (1 pack of 20
             cigarettes per day for 20 years)

          -  Has a history of respiratory tract infection or recent change in pulmonary status
             within 4 weeks of screening

          -  Has a history of chronic bronchitis, defined as cough that produces >1 tablespoon of
             phlegm, that occurs every day for at least 3 months in a row

          -  Has a history of malignancy ≤5 years prior to signing informed consent except for
             adequately treated basal cell or squamous cell skin cancer or cervical cancer

          -  Is a user of recreational or illicit drugs or a recent history (within the last year)
             of drug or alcohol abuse

          -  Has a history of anaphylaxis or cutaneous adverse drug reaction to
             sulfonamide-containing drugs

          -  Has a known allergy to gefapixant or its excipients

          -  Has donated or lost ≥1 unit (~300 mL) of blood within 8 weeks prior to first dose of
             gefapixant

          -  Has previously received gefapixant

          -  Is currently participating or has participated in an interventional clinical study
             within 30 days of participating in this current study