Clinical trial: A Study of Gefapixant (MK-7264) in Adult Participants With Chronic Cough (MK-7264-030) (NCT03449147)

Eligibility criteria:
Inclusion Criteria:

          -  Chest radiograph or computed tomography scan of the thorax (within 5 years 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 sub-investigator

          -  Has had chronic cough for at least 1 year with a diagnosis of refractory chronic cough
             or unexplained chronic cough

          -  Is a female who is not pregnant, not breastfeeding, not of childbearing potential, or
             agrees to follow contraceptive guidance

          -  Provides written informed consent and is willing and able to comply with the study
             protocol (including use of the digital cough recording device and completion of study
             questionnaires)

        Exclusion Criteria:

          -  Is a current smoker or has given up smoking within 12 months of Screening, or is a
             former smoker with greater than 20 pack-years

          -  Has a history of respiratory tract infection or recent clinically significant change
             in pulmonary status

          -  Has a history of chronic bronchitis

          -  Is currently taking an angiotensin converting enzyme inhibitor (ACEI), or has used an
             ACEI within 3 months of Screening

          -  Has an estimated glomerular filtration rate (eGFR) <30 mL/min/1.73 m^2 at Screening OR
             an eGFR ≥30 mL/min/1.73 m^2 and <50 mL/min/1.73 m^2 at Screening with unstable renal
             function

          -  Has a history of malignancy <=5 years

          -  Is a user of recreational or illicit drugs or has had a recent history of drug or
             alcohol abuse or dependence

          -  Has a history of anaphylaxis or cutaneous adverse drug reaction (with or without
             systemic symptoms) to sulfonamide antibiotics or other sulfonamide-containing drugs

          -  Has a known allergy/sensitivity or contraindication to gefapixant

          -  Has donated or lost >=1 unit of blood within 8 weeks prior to the first dose of
             gefapixant

          -  Has previously received gefapixant or is currently participating in or has
             participated in an interventional clinical study
No condition on gender to be admitted to the trial.
No healthy subjects accepted to join the trial.
Subject must be at least 18 Years old.


Patient description (medical language): A 47-year-old man comes to the office for routine checkup. He is complaining of chronic cough and occasional but progressive dyspnea.  Other medical conditions include hypertension and osteoarthritis.  The patient smokes a pack of cigarettes daily and does not use alcohol or illicit drugs.  He used to be a construction worker. On examination, there are decreased breath sounds and percussive dullness at the base of both lungs.  Chest CT scan reveals a mild bilateral pleural effusion and diffuse thickening of the pleura. The patient's documents show chronic exposure to asbestosis. The specimen of the lungs reveled  pulmonary fibrosis that is most predominant in the lower lobes, characterized  by the presence of asbestos bodies (golden-brown beaded rods with translucent centers).

Patient description (patient's own words): I'm a 47-year-old former construction worker. I'm a man and I smoke a pack of cigs a day but I don't drink or do drugs. I went to my routine checkup because I've been coughing so much lately. I also had shortness of breath and it got worse over time. I already suffer from hypertension and osteoarthritis. My doctor found that I have decreased breath sounds. I did a chest scan and it seems that I have fluid around my lungs, and the lining of my lungs has become thicker in many areas. I have been exposed a lot to asbestos fibers. The other lung exam showed that I have pulmonary fibrosis, especially in the lower part of my lungs and they found some asbestos there.

Does the patient match the trial criteria? Entailment