Title

A Study to Assess the Efficacy of Gefapixant (MK-7264/AF-219), in Participants With Chronic Cough (MK-7264-006)
A Study to Assess the Efficacy of AF-219, a P2X3 Receptor Antagonist, in Subjects With Chronic Cough (EPiCC)
  • Phase

    Phase 2
  • Study Type

    Interventional
  • Intervention/Treatment

    gefapixant ...
  • Study Participants

    24
This is a randomised, double-blind, placebo-controlled, crossover, single centre study of gefapixant (AF-219/MK-7264) in participants with idiopathic or treatment resistant chronic cough designed to evaluate the effectiveness of gefapixant in reducing daytime objective cough frequency.
Study Started
Sep 22
2011
Primary Completion
Feb 07
2013
Study Completion
Feb 21
2013
Results Posted
Nov 02
2020
Last Update
Nov 24
2020

Drug Gefapixant

Oral tablets, BID

  • Other names: AF-219, MK-7264

Drug Placebo

Oral tablets, BID

Gefapixant 600 mg>Placebo Experimental

Gefapixant, 600 mg, twice daily (BID), taken orally for 2 weeks followed by a 2-week washout period and then placebo to gefapixant, BID, taken orally for 2 weeks.

Placebo>Gefapixant 600 mg Experimental

Placebo to gefapixant BID, taken orally for 2 weeks followed by a 2-week washout period and then gefapixant, 600 mg, BID, taken orally for 2 weeks.

Criteria

Inclusion Criteria:

History of cough for more than 8 weeks
Normal chest radiograph
Idiopathic or treatment resistant cough (idiopathic defined as a cough for which no objective evidence of an underlying trigger can be determined after investigation or a cough that is unresponsive to 8 weeks of targeted treatment for identified underlying triggers including reflux disease, asthma and post-nasal drip [treatment-resistant]).

Exclusion Criteria:

Current smoker
Individuals who have given up smoking within the past 6 months, or those with >20 pack-year smoking history
Treatment with an angiotensin-converting-enzyme inhibitor (ACE-inhibitor) as the potential cause of a participant's cough, or requiring treatment with an ACE-inhibitor during the study or within 4 weeks prior to Day 0
Forced Expiratory Volume (FEV1)/Forced Vital Capacity (FVC) <60%

Summary

Gefapixant 600 mg

Placebo

All Events

Event Type Organ System Event Term Gefapixant 600 mg Placebo

Change From Baseline in Daytime Objective Cough Frequency

Daytime Objective Cough Frequency (per hour) is the total number of cough events during the monitoring period (in general, 24-hr interval) the participant is awake divided by the total duration (in hours) for the monitoring period the participants is awake. 24-hour sound recordings were collected using a digital recording device. Change from baseline in awake cough frequency = (post-treatment awake cough frequency - baseline awake cough frequency). A negative result indicates a decrease in cough frequency, while a positive result indicates an increase in cough frequency.

Gefapixant 600 mg

-0.5365
Coughs/hour (Log Mean)
Standard Error: 0.1718

Placebo

0.0523
Coughs/hour (Log Mean)
Standard Error: 0.0462

Change From Baseline of Daytime Cough Severity Score Using a Visual Analogue Scale (VAS)

Cough Severity VAS: scored from 0 to 100 using a 10 mm visual analogue scale with 0 at 0mm and 100 at 100mm with 0 representing no cough and 100 the most severe cough. Change from baseline in daytime cough severity = (post-treatment daytime cough severity - baseline daytime cough severity). A negative result indicates a decrease in cough severity, while a positive result indicates an increase in cough severity.

Gefapixant 600 mg

-21.5
Score on a scale (Mean)
Standard Deviation: 35.65

Placebo

-0.7
Score on a scale (Mean)
Standard Deviation: 19.01

Change From Baseline in Nighttime Objective Cough Frequency

Nighttime Objective Cough Frequency = Total number of cough events during the monitoring period the participant is asleep divided by the total duration (in hours) for the monitoring period the participant is asleep. 24 hour sound recording were collected with a digital recording device. Change from baseline in nighttime cough frequency = (post-treatment nighttime cough frequency - baseline nighttime cough frequency). A negative result indicates a decrease in cough frequency, while a positive result indicates an increase in cough frequency.

Gefapixant 600 mg

-0.3452
Coughs/hour (Log Mean)
Standard Error: 0.2314

Placebo

0.069
Coughs/hour (Log Mean)
Standard Error: 0.1767

Change From Baseline of Nighttime Cough Severity Score Using a Visual Analogue Scale (VAS)

Cough Severity VAS: scored from 0 to 100 using a 10 mm visual analogue scale with 0 at 0mm and 100 at 100mm with 0 representing no cough and 100 the most severe cough. Change from baseline in nighttime cough severity = (post-treatment nighttime cough severity - baseline nighttime cough severity). A negative result indicates a decrease in cough severity, while a positive result indicates an increase in cough severity.

Gefapixant 600 mg

-16.1
Score on a scale (Mean)
Standard Deviation: 27.71

Placebo

-3.7
Score on a scale (Mean)
Standard Deviation: 22.05

Change From Baseline of 24-hour Objective Cough Frequency

Total (0-24 hours) Objective Cough Frequency = Total number of cough events during the monitoring period divided by the total duration (in hours, i.e., 24 hours mostly) for the monitoring period. 24-hour sound recordings were collected using a digital recording device. A negative result indicates a decrease in cough frequency, while a positive result indicates an increase in cough frequency.

Gefapixant 600 mg

-0.5562
Coughs/hour (Log Mean)
Standard Error: 0.1795

Placebo

0.0298
Coughs/hour (Log Mean)
Standard Error: 0.0459

Global Rating of Change Score for Cough Frequency

At the end of each study period, participants were asked to complete the global rating of change scale questionnaire. The participants were asked to record whether their cough frequency was "worse", "about the same", or "better". If better or worse, the participants were then asked "by how much" with a 7-category rating scale. Therefore, a 15-point ordered scale was used (1=minimum, a very great deal better to 15=maximum, a very great deal worse with a score of 8=indicating no change).

Gefapixant 600 mg

5.83
Score on a scale (Mean)
Standard Deviation: 4.96

Placebo

8.32
Score on a scale (Mean)
Standard Deviation: 2.28

Global Rating of Change Score for Cough Severity

At the end of each study period, participants were asked to complete the global rating of change scale questionnaire. The participants were asked to record whether their cough severity was "worse", "about the same", or "better". If better or worse, the participants were then asked "by how much" with a 7-category rating scale. Therefore, a 15-point ordered scale was used (1=minimum, a very great deal better to 15=maximum, a very great deal worse with a score of 8=indicating no change).

Gefapixant 600 mg

6.0
Score on a scale (Mean)
Standard Deviation: 4.94

Placebo

8.23
Score on a scale (Mean)
Standard Deviation: 2.25

Change From Baseline in Cough-specific Quality of Life Questionnaire (CQLQ)

The CQLQ Questionnaire included 28 items that described negative aspects of quality of life specific to chronic cough. Subscales include: Physical complaints, Psychosocial issues, Functional abilities, Emotional wellbeing, Extreme physical complaints, and Personal safety fears. Participants indicated their degree of agreement with each statement on a 4 point scale (1 = strongly disagree; 2 = disagree; 3 = agree; 4 = strongly agree). CQLQ scores (28 for least impact, 112 for highest impact) used a mixed effect model with terms for treatment sequence, participant within sequence, treatment, and period. Change from baseline in CQLQ scores = (posttreatment CQLQ scores - baseline CQLQ scores). A negative result indicates a decrease in CQLQ scores (lowest cough impact on health-related quality of life), while a positive result indicates an increase in CQLQ scores (highest cough impact on health-related quality of life).

Gefapixant 600 mg

-10.8
Score on a scale (Mean)
Standard Deviation: 14.23

Placebo

-1.4
Score on a scale (Mean)
Standard Deviation: 6.48

Change From Baseline in Urge to Cough Questionnaire (UtCQ) 100 mm Visual Analogue Scale

UtCQ is determined through the use of a 100mm visual analogue scale (VAS) (ranging between 0 for "no urge to cough" and 100 for "severe urge to cough"). Change from baseline in UtCQ scores = (post-treatment UtCQ scores - baseline UtCQ scores). A negative result indicates a decrease in UtCQ scores (lowest impact), while a positive result indicates an increase in UtCQ scores (highest impact).

Gefapixant 600 mg

-27.2
Score on a scale (Mean)
Standard Deviation: 42.07

Placebo

-6.5
Score on a scale (Mean)
Standard Deviation: 28.59

Baseline Daytime Cough Frequency

Daytime Objective Cough Frequency (per hour) is the total number of cough events during the monitoring period (in general, 24-hr interval) the participant is awake divided by the total duration (in hours) for the monitoring period the participants is awake. 24-hour sound recordings were collected using a digital recording device.

Gefapixant 600 mg

37.09
Coughs/hour (Mean)
Standard Deviation: 32.23

Placebo

65.45
Coughs/hour (Mean)
Standard Deviation: 163.36

Baseline Daytime Cough Severity Score Using a Visual Analogue Scale (VAS)

Cough Severity VAS is scored from 0 to 100 using a 10 mm visual analogue scale with 0 at 0mm and 100 at 100mm with 0 representing no cough and 100 the most severe cough.

Gefapixant 600 mg

48.8
Score on a scale (Mean)
Standard Deviation: 20.73

Placebo

52.7
Score on a scale (Mean)
Standard Deviation: 16.10

Baseline Nighttime Objective Cough Frequency

Nighttime Objective Cough Frequency is the total number of cough events during the monitoring period the participant is asleep divided by the total duration (in hours) for the monitoring period the participant is asleep. 24 hour sound recording were collected with a digital recording device.

Gefapixant 600 mg

4.34
Coughs/hour (Mean)
Standard Deviation: 7.79

Placebo

7.78
Coughs/hour (Mean)
Standard Deviation: 23.80

Baseline Nighttime Cough Severity Score Using a Visual Analogue Scale (VAS)

Nighttime cough severity was scored from 0 to 100 using a 10 mm visual analogue scale with 0 at 0mm and 100 at 100mm with 0 representing no cough and 100 the most severe cough.

Gefapixant 600 mg

31.5
Score on a scale (Mean)
Standard Deviation: 23.86

Placebo

28.8
Score on a scale (Mean)
Standard Deviation: 24.88

Baseline 24-Hour Objective Cough Frequency

Total (0-24 hours) Objective Cough Frequency = Total number of cough events during the monitoring period divided by the total duration (in hours, i.e., 24 hours mostly) for the monitoring period. 24-hour sound recordings were collected using a digital recording device.

Gefapixant 600 mg

26.63
Coughs/hour (Mean)
Standard Deviation: 22.63

Placebo

44.7
Coughs/hour (Mean)
Standard Deviation: 105.16

Baseline Cough-specific Quality of Life Questionnaire (CQLQ)

The CQLQ Questionnaire included 28 items that described negative aspects of quality of life specific to chronic cough. Subscales include: Physical complaints, Psychosocial issues, Functional abilities, Emotional wellbeing, Extreme physical complaints, and Personal safety fears. Participants indicated their degree of agreement with each statement on a 4 point scale (1 = strongly disagree; 2 = disagree; 3 = agree; 4 = strongly agree). CQLQ scores (28 for least impact, 112 for highest impact) used a mixed effect model with terms for treatment sequence, participant within sequence, treatment, and period. Change from baseline in CQLQ scores = (posttreatment CQLQ scores - baseline CQLQ scores). A negative result indicates a decrease in CQLQ scores (lowest cough impact on health-related quality of life), while a positive result indicates an increase in CQLQ scores (highest cough impact on health-related quality of life).

Gefapixant 600 mg

56.3
Score on a scale (Mean)
Standard Deviation: 10.40

Placebo

56.2
Score on a scale (Mean)
Standard Deviation: 10.28

Baseline Urge to Cough Questionnaire (UtCQ) 100 mm Visual Analogue Scale

UtCQ is determined through the use of a 100mm visual analogue scale (VAS) (ranging between 0 for "no urge to cough" and 100 for "severe urge to cough").

Gefapixant 600 mg

63.1
Score on a scale (Mean)
Standard Deviation: 23.10

Placebo

62.5
Score on a scale (Mean)
Standard Deviation: 19.99

Age, Continuous

54.5
Years (Mean)
Standard Deviation: 11.1

Ethnicity (NIH/OMB)

Race (NIH/OMB)

Sex: Female, Male

Period 1

Gefapixant 600 mg>Placebo

Placebo>Gefapixant 600mg

Period 2

Gefapixant 600 mg>Placebo

Placebo>Gefapixant 600mg

Drop/Withdrawal Reasons

Gefapixant 600 mg>Placebo

Placebo>Gefapixant 600mg