Efficacy and Safety of Gefapixant (MK-7264) in Women With Chronic Cough and Stress Urinary Incontinence (MK-7264-042)

Inclusion Criteria: * Has a chest radiograph or computed tomography scan of the thorax (within 5 years of Screening and after the onset of chronic cough) not demonstrating any abnormality considered to be significantly contributing to the chronic cough or any other lung disease * Has chronic cough (defined as duration of \>8 weeks after onset of cough symptoms) for ≥12 months * Has a diagnosis of refractory chronic cough or unexplained chronic cough * Has symptoms of SUI, defined as involuntary loss of urine on effort, physical exertion, or on sneezing or coughing, for ≥3 months * Is a female who is not pregnant, not breastfeeding, not of childbearing potential, or agrees 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 * Has a history of surgery to treat SUI within 1 year of screening * Has a history of other specialized treatments for SUI, including intravesical balloon or urethral bulking agent therapy * Has other external incontinence device currently or within 1 month of screening * Has a history of Grade 3 or higher pelvic organ prolapse previously documented or diagnosed on screening * Has a neurogenic bladder * Has a history of adult nocturnal incontinence * Has a history of continuous urine leakage within 1 month of screening * Has a history of interstitial cystitis * Has a history of neurological disease or injury * Has active or recurrent urinary tract infection * Has a history of having a permanent urinary catheter or any urinary catheterization within 3 months of screening * Has a history of malignancy ≤5 years prior to signing informed consent * Is a user of recreational or illicit drugs or a recent history (within the last year) of drug or alcohol abuse * 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 * Requires certain medications and/or other therapies that may impact their cough or bladder function * Has previously received gefapixant * Is currently participating or has participated in an interventional clinical study within 30 days of participating in this current study