The purpose of this study is to evaluate the efficacy and safety of gefapixant, in improving symptoms of cough-induced stress urinary incontinence (SUI) in adult female participants with refractory or unexplained chronic cough. The primary hypothesis is that gefapixant is superior to placebo in reducing the frequency of cough-induced SUI episodes over 12 weeks.

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

http://engagezone.msd.com/doc/ProcedureAccessClinicalTrialData.pdf