A Study of Gefapixant (MK-7264) in Japanese Adult Participants With Refractory or Unexplained Chronic Cough (MK-7264-038)
Condition: Chronic Cough
MeSH terms: Cough
Intervention: Gefapixant; Placebo
Intervention description: Gefapixant 15 mg or 45 mg tablet administered orally BID; Placebo matched to gefapixant 15 mg or 45 mg administered orally BID
Phase: Phase 3
Study type: Interventional
Primary purpose: Treatment
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Double (Participant, Investigator)
Enrollment: 175.0
Sex: All
Minimum age: 20 Years
Healthy volunteers: No

Summary:

      The primary objective of this study is to evaluate the safety of two doses of gefapixant
      (MK-7264) in Japanese adult participants with refractory or unexplained chronic cough.
    

Eligibility criteria:

        Inclusion Criteria:

          -  Chest radiograph or computed tomography scan of the thorax 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 sub-investigator.

          -  Chronic cough for ≥ 4 months and a diagnosis of refractory or unexplained chronic
             cough.

          -  Persistent cough, despite treatment in accordance with the latest guideline of cough
             from the Japanese Respiratory Society, cough is a burden to the participant, and needs
             further treatment.

          -  If female, is not pregnant, not breast-feeding, and either is not a woman of
             childbearing potential or agrees to follow the contraceptive guidance.

        Exclusion Criteria:

          -  Current smoker, or has given up smoking within 12 months of Screening.

          -  History of upper or lower respiratory tract infection or recent clinically significant
             change in pulmonary status.

          -  Has a history of chronic bronchitis.

          -  Current use of an angiotensin converting enzyme inhibitor (ACEI) or has taken an ACEI
             within 3 months of Screening.

          -  Estimated glomerular filtration rate (eGFR) <30 mL/min/1.73 m^2 OR ≥30 mL/min/1.73 m^2
             and <50 mL/min/1.73 m^2 at Visit 1 with unstable renal function (defined as a ≥50%
             increase of serum creatinine compared to a value obtained at least 6 months prior to
             Visit 1).

          -  History of malignancy ≤ 5 years.

          -  User of recreational or illicit drugs or has had a recent history (within the last
             year) of drug or alcohol abuse or dependence.

          -  Systolic blood pressure >160 mm Hg or a diastolic blood pressure >90 mm Hg at
             Screening.

          -  History of cutaneous adverse drug reaction to sulfonamide antibiotics or other
             sulfonamide-containing drugs.

          -  Known allergy/sensitivity or contraindication to gefapixant.

          -  Donated or lost ≥1 unit of blood within 8 weeks prior to the first dose of gefapixant.

          -  Previously received gefapixant or is currently participating in or has participated in
             an interventional clinical study.