Clinical trial NCT04525885: A Study of Gefapixant (MK-7264) in Adult Participants With Chronic Cough (MK-7264-030)-China Extension
Official title: A Phase 3, Randomized, Double-Blind, Placebo-Controlled, 12-Month Study to Evaluate the Efficacy and Safety of MK-7264 in Adult Participants With Chronic Cough (PN030)
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: PHASE3
Conditions: Chronic Cough
Lead sponsor: Merck Sharp & Dohme LLC
Sponsor class: INDUSTRY
First posted: 2020-08-25
Enrollment: 161
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: PARALLEL
Intervention model description: Participants with refractory or unexplained chronic cough will be randomized to 1 of 3 treatment groups: gefapixant 45 mg twice daily (BID), gefapixant 15 mg BID, or placebo.
Primary purpose: TREATMENT

Brief summary: The primary objective of this study will be to evaluate the efficacy of gefapixant (MK-7264) in reducing cough frequency as measured over a 24-hour period. It is hypothesized that at least one dose of gefapixant is superior to placebo in reducing coughs per hour (over 24 hours) at Week 24.

Detailed description: This study will have a main 24-week treatment period and a 28-week extension period of treatment. Participants at selected sites and countries who complete the main and extension study periods may consent to participate in an observational, 3-month, Off-treatment Durability Study Period.

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

Primary outcomes:
measure: Model-Based Geometric Mean Ratio (GMR) of 24-Hour Coughs Per Hour at Week 24
timeFrame: Baseline, Week 24
measure: Percentage of Participants Who Experienced At Least One Adverse Event (AE) During Treatment and Follow-up
timeFrame: Up to 54 weeks
measure: Percentage of Participants Who Discontinued Treatment Due to an AE
timeFrame: Up 52 weeks
Secondary outcomes:
measure: Model-Based GMR of Awake Coughs Per Hour at Week 24/Baseline
timeFrame: Baseline, Week 24
measure: Percentage of Participants With a ≥1.3-point Increase From Baseline in the Leicester Questionnaire (LCQ) Total Score at Week 24
timeFrame: Baseline, Week 24
measure: Percentage of Participants With a ≥30% Reduction From Baseline in 24-hour Coughs Per Hour at Week 24
timeFrame: Baseline, Week 24
measure: Percentage of Participants With ≥1.3-point Reduction From Baseline of Mean Weekly Cough Severity Diary (CSD) Total Score at Week 24
timeFrame: Baseline, Week 24
measure: Percentage of Participants With ≥2.7-point Reduction From Baseline of Mean Weekly CSD Total Score at Week 24
timeFrame: Baseline, Week 24
measure: Percentage of Participants With a ≥30 mm Reduction From Baseline in Cough Severity Visual Analog Scale (VAS) Score at Week 24
timeFrame: Baseline, Week 24
Other outcomes:
Locations:
city: Fuzhou
country: China
facility: The First Affiliated Hospital of Fujian Medical University ( Site 5017)
state: Fujian
city: Guangzhou
country: China
facility: The First Affiliated Hospital of Guangzhou Medical University ( Site 5000)
state: Guangdong
city: Hohhot
country: China
facility: Inner Mongolia Autonomous Region Hospital ( Site 5018)
state: Inner Mongolia
city: Nanchang
country: China
facility: The First Affiliated Hospital of Nanchang University ( Site 5012)
state: Jiangxi
city: Shenyang
country: China
facility: ShengJing Hospital of China Medical University ( Site 5024)
state: Liaoning
city: Shanghai
country: China
facility: Shanghai General Hospital ( Site 5010)
state: Shanghai
city: Hangzhou
country: China
facility: The First Affiliated Hospital of Zhejiang University ( Site 5014)
state: Zhejiang
city: Beijing
country: China
facility: Peking University Third Hospital ( Site 5005)
Study officials:
affiliation: Merck Sharp & Dohme LLC
name: Medical Director
role: STUDY_DIRECTOR
References: