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

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)

The primary objectives of this study are to evaluate the efficacy of gefapixant (MK-7264) in reducing cough frequency as measured over a 24-hour period, and to determine the safety and tolerability of gefapixant. The primary hypothesis is that at least one dose of gefapixant is superior to placebo in reducing coughs per hour (over 24 hours) at Week 24.

Study Overview

• Status: Completed
• Conditions: Chronic Cough
• Intervention / Treatment: Drug: Placebo; Drug: Gefapixant 15 mg BID; Drug: Gefapixant 45 mg BID

Detailed Description

This study will have a main 24-week treatment period and a 28-week extension period of treatment (total treatment period of 52 weeks). Participants at selected sites and countries who complete the main and extension study periods may consent to participate in an observational, 12-week, Off-treatment Durability Study Period. Any assessments conducted in the observational period will be exploratory.

• Study Type: Interventional
• Enrollment (Actual): 1317
• Phase: Phase 3

Contacts and Locations

Study Locations

• Australia
  • Murdoch, Australia, 6150
    • Trialswest ( Site 0208)
  • New South Wales
    • Maroubra, New South Wales, Australia, 2035
      • Australian Clinical Research Network ( Site 0201)
    • Sydney, New South Wales, Australia, 2010
      • Holdsworth House Medical Practice ( Site 0206)
  • South Australia
    • Adelaide, South Australia, Australia, 5000
      • Royal Adelaide Hospital [Adelaide, Australia] ( Site 0214)
• Canada
  • Quebec, Canada, G1N 4V3
    • Diex Recherche Quebec Inc ( Site 0515)
  • Quebec, Canada, G1V 4W2
    • Clinique Specialisee en Allergie de la Capitale - CSAC ( Site 0504)
  • Ontario
    • Hamilton, Ontario, Canada, L8M 1K7
      • Hamilton Medical Research Group ( Site 0510)
  • Quebec
    • Montreal, Quebec, Canada, H1M 1B1
      • Recherche GCP Research ( Site 0500)
    • Sherbrooke, Quebec, Canada, J1J 2G2
      • Q & T Research Sherbrooke Inc. ( Site 0512)
    • St-Charles-Borromee, Quebec, Canada, J6E 2B4
      • Clinique de Pneumologie et du Sommeil de Lanaudiere- CPSL ( Site 0516)
    • Trois-Rivieres, Quebec, Canada, G8T 7A1
      • CIC Mauricie Inc. ( Site 0503)
    • Victoriaville, Quebec, Canada, G6P 6P6
      • Diex Recherche Victoriaville Inc. ( Site 0514)
• China
  • Beijing, China, 100191
    • Peking University Third Hospital ( Site 5005)
  • Fujian
    • Fuzhou, Fujian, China, 350005
      • The First Affiliated Hospital of Fujian Medical University ( Site 5017)
  • Guangdong
    • Guangzhou, Guangdong, China, 510120
      • The First Affiliated Hospital of Guangzhou Medical University ( Site 5000)
  • Inner Mongolia
    • Hohhot, Inner Mongolia, China, 010017
      • Inner Mongolia Autonomous Region Hospital ( Site 5018)
  • Jiangxi
    • Nanchang, Jiangxi, China, 330006
      • The First Affiliated Hospital of Nanchang University ( Site 5012)
  • Liaoning
    • Shenyang, Liaoning, China, 110004
      • ShengJing Hospital of China Medical University ( Site 5024)
  • Shanghai
    • Shanghai, Shanghai, China, 200080
      • Shanghai General Hospital ( Site 5010)
  • Zhejiang
    • Hangzhou, Zhejiang, China, 310003
      • The First Affiliated Hospital of Zhejiang University ( Site 5014)
• Colombia
  • Bogota, Colombia, 110221
    • MedPlus Medicina Prepagada S.A. ( Site 0612)
  • Bucaramanga, Colombia, 681004
    • Instituto Neumologico del Oriente S.A. ( Site 0649)
  • Medellin, Colombia, 050010
    • Inst. Prestadora de Servicios de Salud Universidad Antioquia ( Site 0621)
  • Antioquia
    • Medellin, Antioquia, Colombia, 050021
      • Fundacion Centro de Investigacion Clinica CIC ( Site 0603)
    • Medellin, Antioquia, Colombia, 050034
      • Hospital Pablo Tobon Uribe ( Site 0600)
    • Medellin, Antioquia, Colombia, 050036
      • Universidad Pontificia Bolivariana - Clinica Universitaria Bolivariana ( Site 0602)
  • Cundinamarca
    • Bogota, Cundinamarca, Colombia, 110311
      • Neumo Investigaciones SAS ( Site 0622)
    • Bogota, Cundinamarca, Colombia, 111831
      • Centro Especializado en Enfermedades Pulmonares. ( Site 0620)
  • Valle Del Cauca
    • Cali, Valle Del Cauca, Colombia, 760032
      • Fundacion Valle del Lili ( Site 0618)
    • Cali, Valle Del Cauca, Colombia, 760042
      • Centro Medico Imbanaco de Cali S.A ( Site 0619)
• Czechia
  • Brandys nad Labem, Czechia, 250 01
    • MUDr. I. Cierna Peterova s.r.o. ( Site 0707)
  • Jindrichuv Hradec III, Czechia, 377 01
    • MediTrial s.r.o ( Site 0702)
  • Karlovy Vary, Czechia, 360 17
    • Ordinace Pneumologie a diagnostiky Plicnich funkci ( Site 0705)
  • Novy Bor, Czechia, 473 01
    • PNEUMO-NB s.r.o. ( Site 0710)
  • Tabor, Czechia, 390 03
    • Nemocnice Tabor a.s. ( Site 0703)
• Denmark
  • Herlev, Denmark, 2730
    • Herlev Hospital ( Site 0803)
  • Kobenhavn NV, Denmark, 2400
    • Bispebjerg Hospital ( Site 0804)
• Germany
  • Berlin, Germany, 10969
    • Aerztezentrum Axel Springer Passage ( Site 1009)
  • Berlin, Germany, 12043
    • Atemwegszentrum Neukoeln ( Site 1003)
  • Frankfurt, Germany, 60318
    • Gemeinschaftspraxis Zentrum ( Site 1005)
  • Hannover, Germany, 30173
    • Pneumologicum im Suedstadtforum ( Site 1004)
  • Leipzig, Germany, 04207
    • Pneumologenzentrum ( Site 1006)
  • Neu-Isenburg, Germany, 63263
    • Ballenberger Freytag Wenisch Institut fuer klinische Forschung GmbH ( Site 1011)
  • Ulm, Germany, 89073
    • PneumoConsult Ulm ( Site 1008)
• Guatemala
  • Guatemala, Guatemala, 01001
    • Clinipharm ( Site 2902)
  • Guatemala, Guatemala, 01010
    • Celan SA ( Site 2900)
  • Guatemala, Guatemala, 01010
    • Consultorio Privado Dr. Jeremias Guerra ( Site 2909)
  • Guatemala, Guatemala, 01011
    • Clinica Medica Especializada en Neumologia ( Site 2901)
  • Guatemala, Guatemala, 01015
    • Clinica Privada Dr. Jose Francisco Flores Lopez ( Site 2903)
• Hungary
  • Balassagyarmat, Hungary, 2660
    • Dr Kenessey Albert Korhaz-Rendelointezet ( Site 1200)
  • Budapest, Hungary, 1036
    • Synexus Magyarorszag Kft. ( Site 1208)
  • Godollo, Hungary, 2100
    • Erzsebet Gondozohaz ( Site 1207)
  • Gyula, Hungary, 5700
    • Synexus Magyarorszag Kft. ( Site 1210)
  • Kapuvar, Hungary, 9330
    • Lumniczer Sandor Korhaz es Rendelointezet ( Site 1212)
  • Miskolc, Hungary, 3529
    • CRU Hungary KFT ( Site 1205)
  • Pecs, Hungary, 7626
    • Da Vinci Private Clinic - Da Vinci Maganklinika ( Site 1201)
  • Puspokladany, Hungary, 4150
    • Puspokladanyi Egeszsegugyi Szolgaltato Nonprofit Kft ( Site 1203)
• Israel
  • Rehovot, Israel, 7661041
    • Kaplan Medical Center ( Site 1300)
• Italy
  • Firenze, Italy, 50134
    • Azienda Ospedaliero Universitaria Careggi ( Site 1400)
• Malaysia
  • Kuala Lumpur, Malaysia, 53000
    • Institut Perubatan Respiratori ( Site 1605)
  • Kuala Lumpur, Malaysia, 59100
    • University Malaya Medical Centre ( Site 1601)
  • Kedah
    • Alor Star, Kedah, Malaysia, 05460
      • Hospital Sultanah Bahiyah ( Site 1607)
  • Perak
    • Taiping, Perak, Malaysia, 34000
      • Hospital Taiping ( Site 1600)
  • Pulau Pinang
    • George town, Pulau Pinang, Malaysia, 10990
      • Hospital Pulau Pinang. ( Site 1606)
  • Selangor
    • Batu Caves, Selangor, Malaysia, 68100
      • Universiti Teknologi MARA ( Site 1602)
• New Zealand
  • Auckland, New Zealand, 0626
    • Southern Clinical Trials - Waitemata ( Site 0230)
  • Auckland, New Zealand, 2025
    • Middlemore Clinical Trials ( Site 0232)
  • Rotorua, New Zealand, 3010
    • Lakeland Clinical Trials ( Site 0233)
  • Tauranga, New Zealand, 3110
    • P3 Research Ltd. ( Site 0228)
• Peru
  • Cusco, Peru, 08000
    • Hospital Nacional Adolfo Guevara Velasco ( Site 1808)
  • Lima, Peru, 15046
    • Asociacion Civil por la Salud ( Site 1805)
  • Lima, Peru, 15001
    • Clinica Internacional ( Site 1801)
  • Lima, Peru, 15102
    • Hospital Nacional Cayetano Heredia [Lima, Peru] ( Site 1806)
  • Lima
    • San Isidro, Lima, Peru, 15036
      • Clinica Ricardo Palma ( Site 1802)
• Poland
  • Białystok, Poland, 15-044
    • Centrum Medycyny Oddechowej Mroz Spolka Jawna ( Site 1918)
  • Bychawa, Poland, 23-100
    • KLIMED ( Site 1902)
  • Katowice, Poland, 40-851
    • Gyncentrum Clinic Sp. z o.o. ( Site 1908)
  • Krakow, Poland, 30-033
    • Specjalistyczny osrodek .All-Med. Grazyna Pulka ( Site 1919)
  • Krakow, Poland, 31-011
    • Centrum Nowoczesnych Terapii Dobry Lekarz ( Site 1924)
  • Lodz, Poland, 90-141
    • Uniwersytecki Szpital Kliniczny im. Norberta Barlickiego nr 1 ( Site 1921)
  • Ostrowiec Swietokrzyski, Poland, 27-400
    • Ostrowieckie Centrum Medyczne ( Site 1915)
  • Sochaczew, Poland, 96-500
    • RCMed ( Site 1912)
  • Swidnik, Poland, 21-040
    • Lubelskie Centrum Diagnostyczne ( Site 1913)
  • Warszawa, Poland, 01-868
    • Centrum Medyczne Pratia Warszawa ( Site 1911)
  • Zawadzkie, Poland, 47-120
    • Centrum Medyczne Lucyna Andrzej Dymek - Zawadzkie ( Site 1923)
  • Lubelskie
    • Lublin, Lubelskie, Poland, 20-552
      • NZOZ CENTRUM ALERGOLOGII ( Site 1909)
  • Slaskie
    • Katowice, Slaskie, Poland, 40-081
      • Centrum Medyczne Pratia Katowice ( Site 1917)
    • Katowice, Slaskie, Poland, 40-282
      • Centrum Medyczne Silmedic Sp z o o ( Site 1920)
• South Africa
  • Bloemfontein
    • Brandwag, Bloemfontein, South Africa, 9301
      • Iatros International ( Site 2130)
  • Gauteng
    • Morningside, Gauteng, South Africa, 2196
      • Rochester Place Medical Centre ( Site 2129)
    • Pretoria, Gauteng, South Africa, 0183
      • Jongaie Research ( Site 2131)
  • Kwazulu Natal
    • Shallcross, Kwazulu Natal, South Africa, 4093
      • Dr N K Gounden Mediclinic ( Site 2134)
    • Umhlanga Ridge, Kwazulu Natal, South Africa, 4319
      • Drs Lalloo & Ambaram ( Site 2132)
  • Tswane
    • Centurion, Tswane, South Africa, 0157
      • I Engelbrecht Research ( Site 2128)
  • Western Cape
    • Cape Town, Western Cape, South Africa, 7700
      • UCT Lung Institute - Bateman ( Site 2126)
• Turkey
  • Adana, Turkey, 01330
    • Cukurova Universitesi Tıp Fakultesi Balcalı Hastanesi ( Site 2612)
  • Ankara, Turkey, 06100
    • Ankara Universitesi Tip Fakultesi Cebeci Hastanesi ( Site 2602)
  • Edirne, Turkey, 22030
    • Trakya Universitesi Saglik Arastirma ve Uygulama Merkezi ( Site 2619)
  • Istambul, Turkey, 34093
    • Istanbul Universitesi Istanbul Tip Fakultesi Gogus Hastalıklari ABD ( Site 2610)
  • Istambul, Turkey, 34844
    • SSK Sureyyapasa Gogus Hastaliklari Hastanesi ( Site 2608)
  • Izmir, Turkey, 35040
    • Ege Universitesi Tip Fakultesi Hastanesi ( Site 2603)
  • Izmir, Turkey, 35110
    • SBU Dr. Suat Seren Gogus Hast. ve Cer. Egitim ve Arastirma Hast. ( Site 2604)
  • Manisa, Turkey, 45030
    • Celal Bayar University Faculty of Medicine ( Site 2614)
  • Gorukle
    • Bursa, Gorukle, Turkey, 16059
      • Uludag Universitesi Tip Fakultesi ( Site 2621)
• Ukraine
  • Chernihiv, Ukraine, 14034
    • Chernihiv City hospital N2 ( Site 2801)
  • Chernivtsi, Ukraine, 58022
    • CE Chernivtsi state city clinical hospital 3 ( Site 2806)
  • KYiv, Ukraine, 03049
    • SE Road Clinical Hospital 2 of Kyiv station ( Site 2809)
  • Kherson, Ukraine, 73000
    • Kherson City Clinical Hospital n.a. Y.Y. Karabelesh ( Site 2812)
  • Kiev, Ukraine, 01023
    • Medical Clinic Blagomed LLC ( Site 2807)
  • Kyiv, Ukraine, 03680
    • F.G.Yanovskyy Institute of Phthisiology and Pulmonology ( Site 2830)
  • Kyiv, Ukraine, 02091
    • Kyiv City Tuberculosis Hospital No. 1 ( Site 2814)
  • Kyiv, Ukraine, 03037
    • Medical Association Medbud of the PJSC Kyivmiskbud ( Site 2803)
  • Kyiv, Ukraine, 03067
    • Institute of Otolaryngology n. a. Prof. A. I. Kolomiychenko ( Site 2833)
  • Kyiv, Ukraine, 03680
    • F.G.Yanovskyy Institute of Phthisiology and Pulmonology ( Site 2804)
  • Lutsk, Ukraine, 43005
    • Volyn Regional Clinical Hospital ( Site 2829)
  • Poltava, Ukraine, 36039
    • Poltava City Clinical Hospital 1 ( Site 2808)
  • Vinnytsia, Ukraine, 21018
    • Vinnytsia Regional Clinical Hospital n.a. M.I. Pyrogov ( Site 2819)
  • Zaporizhzhia, Ukraine, 69065
    • MI Zaporizhzhia City Multispecialty Clinical Hospital 9 ( Site 2811)
  • Zhytomyr, Ukraine, 10002
    • Zhytomyr Central City Hospital #1 ( Site 2828)
• United Kingdom
  • Belfast, United Kingdom, BT9 7AB
    • Belfast City Hospital ( Site 2705)
  • Glasgow, United Kingdom, G20 0SP
    • Synexus Scotland Clinical Research Centre ( Site 2721)
  • Liverpool, United Kingdom, L22 OLG
    • Synexus Merseyside Clinical Research Centre ( Site 2720)
  • Llanelli, United Kingdom, SA14 8QF
    • Prince Phillip Hospital ( Site 2722)
  • London, United Kingdom, SE5 9RS
    • 1Kings College Hospital ( Site 2702)
  • Manchester, United Kingdom, M23 9LT
    • Wythenshawe Hospital ( Site 2700)
  • Manchester, United Kingdom, M15 6SE
    • Synexus Manchester Clinical Research Centre ( Site 2718)
  • North Shields, United Kingdom, NE29 8NH
    • North Tyneside General Hospital ( Site 2707)
  • Rothwell, United Kingdom, NN14 6JQ
    • Rothwell Medical Centre ( Site 2712)
  • Taunton, United Kingdom, TA1 5DA
    • Taunton and Somerset Hospital ( Site 2723)
  • Yate, United Kingdom, BS37 4AX
    • West Walk Surgery ( Site 2711)
  • East Yorkshire
    • Cottingham, East Yorkshire, United Kingdom, HU16 5JQ
      • Hull & East Yorkshire NHS Trust. Castle Hill Hospital ( Site 2704)
  • Edgbaston
    • Birmingham, Edgbaston, United Kingdom, B15 2SQ
      • Synexus Midlands Clinical Research Centre Ltd ( Site 2719)
  • Essex
    • Romford, Essex, United Kingdom, RM1 3PJ
      • Medinova East London Dedicated Research Centre ( Site 2715)
  • Kent
    • Sidcup, Kent, United Kingdom, DA14 6LT
      • Medinova South London Dedicated Research Centre ( Site 2714)
  • Middlesex
    • Northwood, Middlesex, United Kingdom, HA6 2RN
      • Medinova North London Dedicated Research Centre ( Site 2716)
  • Northamptonshire
    • Corby, Northamptonshire, United Kingdom, NN17 2UR
      • Medinova Lakeside Dedicated Research Centre ( Site 2710)
  • Warwickshire
    • Kenilworth, Warwickshire, United Kingdom, CV8 1JD
      • Medinova Warwickshire Dedicated Research Centre ( Site 2717)
• United States
  • Arizona
    • Peoria, Arizona, United States, 85381
      • Phoenix Medical Group ( Site 0022)
    • Phoenix, Arizona, United States, 85006
      • Pulmonary Associates, PA ( Site 0063)
    • Tempe, Arizona, United States, 85283
      • Clinical Research Consortium ( Site 0088)
  • California
    • San Jose, California, United States, 95117
      • Allergy & Asthma Associates of SCV Research Center ( Site 0064)
  • Florida
    • Sweetwater, Florida, United States, 33172
      • Lenus Research & Medical Group Llc ( Site 0075)
  • Georgia
    • Stockbridge, Georgia, United States, 30281
      • Atlanta Allergy & Asthma Clinic PA ( Site 0029)
  • Illinois
    • Chicago, Illinois, United States, 60612
      • Rush University Medical Center ( Site 0103)
    • Flossmoor, Illinois, United States, 60422
      • Healthcare Research Network LLC ( Site 0093)
  • Kentucky
    • Fort Mitchell, Kentucky, United States, 41017
      • Abraham Research, PLLC ( Site 0107)
  • Maine
    • Bangor, Maine, United States, 04401
      • Paul A. Shapero, MD ( Site 0104)
  • Maryland
    • Bethesda, Maryland, United States, 20814
      • Bethesda Allergy Asthma and Research Center LLC ( Site 0019)
  • Michigan
    • Ypsilanti, Michigan, United States, 48197
      • Respiratory Medicine Research Institute of Michigan, PLC ( Site 0034)
  • Minnesota
    • Edina, Minnesota, United States, 55435
      • Minnesota Lung Center ( Site 0108)
    • Rochester, Minnesota, United States, 55905
      • Mayo Clinic - Rochester ( Site 0006)
    • Woodbury, Minnesota, United States, 55125
      • Minnesota Lung Center ( Site 0041)
  • Missouri
    • Chesterfield, Missouri, United States, 63017
      • The Lung Research Center ( Site 0072)
    • Columbia, Missouri, United States, 65201
      • University of Missouri ENT & Allergy Center ( Site 0066)
  • Nebraska
    • Omaha, Nebraska, United States, 68134
      • CHI Health Creighton University Medical Center ( Site 0024)
  • Nevada
    • Las Vegas, Nevada, United States, 89109
      • Clinical Research Consortium ( Site 0050)
  • New Jersey
    • Ocean City, New Jersey, United States, 07712
      • Atlantic Research Center LLC ( Site 0012)
  • New Mexico
    • Albuquerque, New Mexico, United States, 87102
      • Albuquerque Clinical Trials ( Site 0039)
  • New York
    • Bronx, New York, United States, 10461
      • Montefiore Medical Center ( Site 0098)
  • North Carolina
    • Raleigh, North Carolina, United States, 27612
      • Wake Research Associates, LLC ( Site 0058)
  • Ohio
    • Columbus, Ohio, United States, 43215
      • Remington-Davis, Inc. ( Site 0082)
  • Oregon
    • Medford, Oregon, United States, 97504
      • Clinical Research Institute of Southern Oregon, PC ( Site 0099)
    • Portland, Oregon, United States, 97202
      • Allergy Associates Research Center ( Site 0026)
  • Rhode Island
    • Warwick, Rhode Island, United States, 02886
      • AAPRI Clinical Research Institute ( Site 0001)
  • South Carolina
    • Charleston, South Carolina, United States, 29406
      • Lowcountry Lung & Critical Care, PA ( Site 0045)
    • Greenville, South Carolina, United States, 29607
      • Allergic Disease and Asthma Center ( Site 0043)
    • Rock Hill, South Carolina, United States, 29732
      • Clinical Research of Rock Hill ( Site 0079)
  • Virginia
    • Richmond, Virginia, United States, 23235
      • Clinical Research Partners, LLC. ( Site 0080)
  • Washington
    • Bellingham, Washington, United States, 98225
      • Bellingham Asthma & Allergy ( Site 0076)
    • Spokane, Washington, United States, 99202
      • Marycliff Clinical Research ( Site 0062)
    • Tacoma, Washington, United States, 98405
      • Multicare Health System ( Site 0018)

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

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
• Currently participating in or has participated in an interventional clinical study within 30 days of screening

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Placebo Comparator: Placebo; Participants will receive a matching placebo tablet BID during the 24-week main study period and the 28-week extension period.	Drug: Placebo; Placebo tablet administered orally BID
Experimental: Gefapixant 15 mg BID; Participants will receive a gefapixant 15 mg tablet BID and placebo tablet to match gefapixant 45 mg BID during the 24-week main study period and the 28-week extension period.	Drug: Placebo; Placebo tablet administered orally BID; Drug: Gefapixant 15 mg BID; Gefapixant 15 mg tablet administered orally BID; Other Names: MK-7264
Experimental: Gefapixant 45 mg BID; Participants will receive a gefapixant 45 mg tablet BID and placebo tablet to match gefapixant 15 mg BID during the 24-week main study period and during the 28-week extension period.	Drug: Placebo; Placebo tablet administered orally BID; Drug: Gefapixant 45 mg BID; Gefapixant 45 mg tablet administered orally BID; Other Names: MK-7264

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Model-Based Geometric Mean Ratio (GMR) of 24-Hour Coughs Per Hour at Week 24/Baseline	24-hour coughs per hour was defined as the average hourly cough frequency based on 24-hour sound recordings using a digital recording device (cough monitor). A longitudinal analysis of covariance (ANCOVA) model was applied to log-transformed cough data to determine geometric mean (GM) 24-hour coughs per hour at baseline and week 24. The GMR (Week 24 GM 24-hour coughs per hour divided by Baseline GM 24-hour coughs per hour) is reported.	Baseline, Week 24
Number of Participants Who Experienced At Least One Adverse Event (AE) During Treatment and Follow-up	An AE is any untoward medical occurrence in a clinical study participant, temporally associated with the use of study intervention, whether or not considered related to the study intervention. An AE can therefore be any unfavorable and unintended sign (including an abnormal laboratory finding), symptom, or disease (new or exacerbated) temporally associated with the use of a study intervention.	Up to 54 Weeks
Number of Participants Who Discontinued a Study Drug Due to an AE	An AE is any untoward medical occurrence in a clinical study participant, temporally associated with the use of study intervention, whether or not considered related to the study intervention. An AE can therefore be any unfavorable and unintended sign (including an abnormal laboratory finding), symptom, or disease (new or exacerbated) temporally associated with the use of a study intervention.	Up to 52 weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Model-Based GMR of Awake Coughs Per Hour at Week 24/Baseline	Awake coughs per hour was defined as the average hourly cough frequency while the participant is awake, based on a 24-hour interval of sound recordings using a digital recording device (cough monitor). ANCOVA model was applied to log-transformed cough data to determine GM of awake coughs per hour at baseline and week 24. The GMR (Week 24 GM awake coughs per hour divided by Baseline GM awake coughs per hour) is reported.	Baseline, Week 24
Percentage of Participants With a ≥1.3 Point Change From Baseline in the Leicester Questionnaire (LCQ) Total Score at Week 24	The 19-item LCQ assessed the impact of chronic cough in three health-related quality of life (HRQoL) domains (physical, social and psychological). The LCQ is calculated as a mean score for each domain ranging from 1 to 7, with a total score ranging from 3 to 21. Higher scores indicate better HRQoL. A clinically meaningful improvement from baseline in HRQoL was defined as ≥1.3-point increase in the LCQ total score at Week 24. The percentage of participants (logistic regression model-based) with a ≥1.3-point increase in the LCQ total score at Week 24 is presented.	Baseline, Week 24
Percentage of Participants With a ≤-30% Change From Baseline in 24-hour Coughs Per Hour at Week 24	24-hour coughs per hour was defined as the average hourly cough frequency based on 24-hour sound recordings using a digital recording device (cough monitor). A clinically meaningful improvement from baseline is defined as a ≤-30% change (≥30% reduction) in 24-hour coughs per hour at week 24. The percentage of participants (logistic regression model-based) with a ≤ -30% change from baseline in 24-hour coughs per hour at Week 24 (≥30% reduction from baseline) is presented.	Baseline, Week 24
Percentage of Participants With ≤-1.3 Point Change From Baseline of Mean Weekly Cough Severity Diary (CSD) Total Score at Week 24	The 7-item CSD was used to record participants' daily cough frequency, cough intensity, and disruption due to cough. Each item was rated on an 11-point scale ranging from 0 (best) to 10 (worst); the total daily CSD score was the sum of these seven item scores (Min=0, Max=70). Mean weekly CSD total score was defined as the average of the mean total daily scores collected during the week prior to each visit. The percentage of participants (logistic regression model-based) with a ≤-1.3 point change from baseline in CSD at Week 24 (or ≥1.3 point reduction from baseline) is reported.	Baseline, Week 24
Percentage of Participants With ≤-2.7 Point Change From Baseline of Mean Weekly CSD Total Score at Week 24	The 7-item CSD was used to record participants' daily cough frequency, cough intensity, and disruption due to cough. Each item was rated on an 11-point scale ranging from 0 (best) to 10 (worst); the total daily CSD score was the sum of these seven item scores (Min=0, Max=70). Mean weekly CSD total score was defined as the average of the mean total daily scores collected during the week prior to each visit. The percentage of participants (logistic regression model-based) with a ≤-2.7 point change from baseline in CSD at Week 24 (or ≥2.7 point reduction from baseline) is reported.	Baseline, Week 24
Percentage of Participants With a ≤-30 Millimeter (mm) Change From Baseline in Cough Severity Visual Analog Scale (VAS) Score at Week 24	The VAS is a single-item questionnaire with the response on a 100- point scale ranging from 0 ("No Cough") to 100 ("Extremely Severe Cough"). Mean weekly VAS score was defined as the average of the VAS scores collected during the week prior to each visit. The percentage of participants (logistic regression model-based) with a ≤-30 mm change from baseline in cough severity VAS score at Week 24 is reported.	Baseline, Week 24

Collaborators and Investigators

• Sponsor: Merck Sharp & Dohme LLC

Publications and helpful links

General Publications

• Dicpinigaitis PV, Birring SS, Blaiss M, McGarvey LP, Morice AH, Pavord ID, Satia I, Smith JA, La Rosa C, Li Q, Nguyen AM, Schelfhout J, Tzontcheva A, Muccino D. Demographic, clinical, and patient-reported outcome data from 2 global, phase 3 trials of chronic cough. Ann Allergy Asthma Immunol. 2022 May 13:S1081-1206(22)00406-9. doi: 10.1016/j.anai.2022.05.003. Online ahead of print.
• McGarvey LP, Birring SS, Morice AH, Dicpinigaitis PV, Pavord ID, Schelfhout J, Nguyen AM, Li Q, Tzontcheva A, Iskold B, Green SA, Rosa C, Muccino DR, Smith JA; COUGH-1 and COUGH-2 Investigators. Efficacy and safety of gefapixant, a P2X3 receptor antagonist, in refractory chronic cough and unexplained chronic cough (COUGH-1 and COUGH-2): results from two double-blind, randomised, parallel-group, placebo-controlled, phase 3 trials. Lancet. 2022 Mar 5;399(10328):909-923. doi: 10.1016/S0140-6736(21)02348-5.

Study record dates

Study Major Dates

• Study Start (Actual): March 15, 2018
• Primary Completion (Actual): August 20, 2020
• Study Completion (Actual): October 30, 2020

Study Registration Dates

• First Submitted: February 22, 2018
• First Submitted That Met QC Criteria: February 22, 2018
• First Posted (Actual): February 28, 2018

Study Record Updates

• Last Update Posted (Actual): September 2, 2021
• Last Update Submitted That Met QC Criteria: August 9, 2021
• Last Verified: August 1, 2021

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Respiratory Tract Diseases; Respiration Disorders; Signs and Symptoms, Respiratory; Cough
• Other Study ID Numbers: 7264-030; MK-7264-030 (Other Identifier: Merck Protocol Number); 2017-003559-49 (EudraCT Number)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: Yes
• IPD Plan Description: http://engagezone.msd.com/doc/ProcedureAccessClinicalTrialData.pdf

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No