A Study to Evaluate the Efficacy and Safety of Gefapixant (MK-7264) in Women With Endometriosis-Related Pain (MK-7264-034)

NCT03654326 | Completed Phase 2 Results FDA Drug

• 3 other identifiers: 7264-034MK-7264-0342018-001098-26
• Study Type: interventional
• Target: 187
• Locations: 9 countries
• Sites: 78

Brief Summary

The purpose of this study is to evaluate the efficacy, safety, and tolerability of gefapixant (MK-7264) in premenopausal female participants with moderate to severe endometriosis-related pain. The primary hypothesis: gefapixant is superior to placebo in reducing the average daily pelvic pain score (cyclic and non-cyclic, combined) during Treatment Cycle 2.

Conditions

Endometriosis-related Pain

Outcome Measures

Primary Outcomes (3)

• Change From Baseline in Average Daily Pelvic Pain Score During Treatment Cycle 2

  Pelvic pain (cyclic pain associated with menses, and non-cyclic pain not associated with menses) severity score was measured using a 0-10 numeric rating scale (NRS), with 0 representing no pain and 10 representing extremely severe pain. The averages of the daily pelvic pain scores (cyclic and non-cyclic, combined) entered in participants' electronic diaries (eDiaries) were calculated for Baseline and Treatment Cycle 2 (approximately Week 4 to Week 8). A negative change indicates a decrease in pain severity from baseline.

  Baseline and Treatment Cycle 2 (Week 4 to Week 8; each cycle is approximately 28 days)

• Percentage of Participants Who Experienced an Adverse Event

  An adverse event (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. Per protocol, this analysis included AEs reported up to 14 days after end of study intervention.

  Up to approximately 10 weeks

• Percentage of Participants Who Discontinued Study Drug Due to an Adverse Event

  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 approximately 8 weeks

Secondary Outcomes (2)

• Change From Baseline in Average Daily Cyclic Pelvic Pain Score During Treatment Cycle 2

  Baseline and Treatment Cycle 2 (Week 4 to Week 8; each cycle is approximately 28 days)

• Change From Baseline in Average Daily Non-Cyclic Pelvic Pain Score During Treatment Cycle 2

  Baseline and Treatment Cycle 2 (Week 4 to Week 8; each cycle is approximately 28 days)

Study Arms (2)

Gefapixant

EXPERIMENTAL

Participants will receive a gefapixant 45 mg tablet twice a day for approximately 8 weeks (2 menstrual cycles). Naproxen sodium 275 mg tablets will also be provided to participants for use as rescue medication for endometriosis-related pain.

Drug: Gefapixant; Drug: Placebo; Drug: Naproxen

Placebo

PLACEBO COMPARATOR

Participants will receive a placebo matching gefapixant tablet twice a day for approximately 8 weeks (2 menstrual cycles). Naproxen sodium 275 mg tablets will also be provided to participants for use as rescue medication for endometriosis-related pain.

Drug: Placebo; Drug: Naproxen

Interventions

Gefapixant DRUG

Gefapixant tablet 45 mg taken orally

Also known as: MK-7264

Gefapixant

Placebo DRUG

Placebo matching gefapixant tablet taken orally

Gefapixant; Placebo

Naproxen DRUG

Naproxen sodium 275 mg tablets taken orally as needed, at dose prescribed by sites' principal investigator

Gefapixant; Placebo

Eligibility Criteria

• Age: 18 Years - 49 Years
• Sex: female
• Healthy Volunteers: No
• Age Groups: Adult (18-64)

You may qualify if:

• has been surgically (laparoscopy or laparotomy) diagnosed with endometriosis.
• has cyclic AND non-cyclic, moderate to severe endometriosis-related pelvic pain (overall pelvic pain score ≥5 using a 0-10 NRS, with 0 representing no pain and 10 representing extremely severe pain).
• has had spontaneous menstrual cycles before Visit 1.
• has body mass index (BMI) between 18 kg/m\^2 to 40 kg/m\^2 at Visit 1.
• is not pregnant, not breastfeeding, and agrees to follow the contraceptive guidance.
• must agree to switch from her usual analgesic medication to only that which is permitted in the study.

You may not qualify if:

• history of hysterectomy and/or bilateral oophorectomy.
• has undiagnosed vaginal bleeding.
• has chronic, non-pelvic pain not caused by endometriosis that requires chronic analgesic.
• has a clinically significant gynecologic condition identified in the screening evaluation.
• 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 or its excipients.
• has an allergy/sensitivity/intolerance to naproxen sodium (rescue medication) or any contraindication to its use, or has experienced asthma, urticaria, or allergic-type reactions after taking aspirin or other nonsteroidal anti-inflammatory drugs (NSAIDs).
• has a history of endometriosis-related pain that was non-responsive to treatment with combined hormonal contraceptives (CHCs), gonadotropin-releasing hormone (GnRH) antagonists, GnRH agonists, progestins, or aromatase inhibitors.
• has a positive urine pregnancy test at any time before randomization.
• has required more than 2 weeks of continuous use of narcotics for treatment of endometriosis-related pain within 6 months of Visit 1.

Sponsors & Collaborators

• Merck Sharp & Dohme LLC: lead

Study Sites (78)

Cahaba Medical Care ( Site 0750)

Birmingham, Alabama, 35218, United States

Location

Synexus US Phoenix Southeast ( Site 0729)

Chandler, Arizona, 85224, United States

Location

Synexus ( Site 0734)

Scottsdale, Arizona, 85251, United States

Location

Lynn Institute of the Ozarks ( Site 0720)

Little Rock, Arkansas, 72205, United States

Location

California Center for Clinical Research ( Site 0741)

Arcadia, California, 91007, United States

Location

Artemis Institute for Clinical Research ( Site 0716)

San Diego, California, 92103, United States

Location

Alta California Medical Group ( Site 0721)

Simi Valley, California, 93065, United States

Location

Thameside OBGYN Center ( Site 0747)

Groton, Connecticut, 06340, United States

Location

WHUSA Fine and Gillette ( Site 0751)

Hamden, Connecticut, 06518, United States

Location

Florida Fertility Institute ( Site 0737)

Clearwater, Florida, 33759, United States

Location

Advanced Pharma Research ( Site 0719)

Cutler Bay, Florida, 33189, United States

Location

Doral Medical Research, LLC ( Site 0706)

Doral, Florida, 33166, United States

Location

KO Clinical Research, LLC ( Site 0723)

Fort Lauderdale, Florida, 33316, United States

Location

Well Pharma Medical Research, Corp. ( Site 0703)

Miami, Florida, 33143, United States

Location

L&C Professional Medical Research Institute ( Site 0709)

Miami, Florida, 33144, United States

Location

New Horizon Research Center ( Site 0717)

Miami, Florida, 33465, United States

Location

Inpatient Research Clinic, LLC ( Site 0725)

Miami Lakes, Florida, 33014, United States

Location

QPS Miami Research Associates ( Site 0735)

South Miami, Florida, 33143, United States

Location

Lenus Research & Medical Group Llc ( Site 0702)

Sweetwater, Florida, 33172, United States

Location

Southern Clinical Research Associates ( Site 0701)

Metairie, Louisiana, 70001, United States

Location

Tufts Medical Center ( Site 0742)

Boston, Massachusetts, 02111, United States

Location

Carolina Women's Research and Wellness Center ( Site 0715)

Durham, North Carolina, 27713, United States

Location

Palmetto Clinical Research ( Site 0707)

Summerville, South Carolina, 29485, United States

Location

Chattanooga Medical Research ( Site 0743)

Chattanooga, Tennessee, 37404, United States

Location

Women Partners in Health ( Site 0745)

Austin, Texas, 78705, United States

Location

Corpus Christi Clinic ( Site 0744)

Corpus Christi, Texas, 78412, United States

Location

HD Research Corp ( Site 0738)

Houston, Texas, 77024, United States

Location

PI-Coor Clinical Research, LLC ( Site 0710)

Reston, Virginia, 20190, United States

Location

Clinical Research Partners, LLC. ( Site 0704)

Richmond, Virginia, 23225, United States

Location

Seattle Women's: Health, Research, Gynecology ( Site 0714)

Seattle, Washington, 98105, United States

Location

Paratus Clinical Kanwal ( Site 0004)

Kanwal, New South Wales, 2259, Australia

Location

Royal Hospital for Women ( Site 0008)

Randwick, New South Wales, 2031, Australia

Location

Holdsworth House Medical Practice ( Site 0009)

Sydney, New South Wales, 2010, Australia

Location

Royal Adelaide Hospital ( Site 0007)

Adelaide, South Australia, 5000, Australia

Location

Keogh Institute for Medical Research ( Site 0002)

Nedlands, Western Australia, 6009, Australia

Location

Hospital San Juan de Dios de La Serena ( Site 0110)

La Serena, Coquimbo Region, 1710216, Chile

Location

Hospital San Borja Arriaran ( Site 0103)

Santiago, Santiago Metropolitan, 8360160, Chile

Location

Clinica Indisa [Santiago, Chile] ( Site 0101)

Santiago, 7520440, Chile

Location

Clinica Las Condes ( Site 0109)

Santiago, 7591047, Chile

Location

Clinica Alemana de Santiago ( Site 0107)

Santiago, 7650568, Chile

Location

Southern Clinical Trials - Waitemata ( Site 0200)

Auckland, 0626, New Zealand

Location

Southern Clinical Trials Ltd ( Site 0201)

Christchurch, 8013, New Zealand

Location

Prywatna Klinika Polozniczo - Ginekologiczna ( Site 0300)

Bialystok, 15-224, Poland

Location

Indywidualna Specjalistyczna Praktyka Lekarska Krzysztof Wilk ( Site 0316)

Katowice, 40-301, Poland

Location

SPL Chorob Kobiecych i Połoznictwa dr L. Kobielska ( Site 0339)

Katowice, 40-717, Poland

Location

Clinical Medical Research Sp. z o.o. ( Site 0343)

Katowice, 40-750, Poland

Location

Osrodek Badan Klinicznych Gyncentrum ( Site 0330)

Katowice, 40-851, Poland

Location

LIFTMED ( Site 0325)

Rybnik, 44-200, Poland

Location

Examen Sp. z o.o. ( Site 0318)

Skorzewo, 60-185, Poland

Location

Clinical Best Solutions ( Site 0338)

Warsaw, 02-793, Poland

Location

Marek Elias Gabinety Ginekologiczne ( Site 0331)

Wroclaw, 50-547, Poland

Location

Cooperativa de Facultad Medica Sanacoop ( Site 0805)

Bayamón, 00961, Puerto Rico

Location

Ponce Health Sciences University ( Site 0804)

Ponce, 00717-2348, Puerto Rico

Location

Gynecology & Endometriosis Center LLC ( Site 0806)

San Juan, 00909, Puerto Rico

Location

Henry A. Rodriguez-Ginorio Private Practice ( Site 0800)

San Juan, 00917, Puerto Rico

Location

Genes Fertility Institute Inc. ( Site 0803)

San Juan, 00918, Puerto Rico

Location

Kazan State Medical University ( Site 0404)

Kazan', 420029, Russia

Location

Clinical Hospital #2 of Kazan city ( Site 0406)

Kazan', 420033, Russia

Location

LLC Scientific Research Medical Complex Your Health. ( Site 0405)

Kazan', 420097, Russia

Location

Moscow Regional Research Institute of Tocology and Gynecolog ( Site 0411)

Moscow, 101000, Russia

Location

State Institution of Healthcare Moscow City Clinical Hospital 13 ( Site 0408)

Moscow, 115280, Russia

Location

Women clinic 22 ( Site 0400)

Saint Petersburg, 194354, Russia

Location

NII of Obstetrics, Gynecology and Reproductology n.a. D.O. Ott ( Site 0401)

Saint Petersburg, 199034, Russia

Location

Uromed LLC ( Site 0410)

Smolensk, 214031, Russia

Location

Siberian State Medical University ( Site 0402)

Tomsk, 634050, Russia

Location

Hospital Sanitas La Zarzuela ( Site 0502)

Aravaca, Madrid, 28023, Spain

Location

Instituto de Ciencias Medicas.ICM ( Site 0500)

Alicante, 03004, Spain

Location

Hospital Clinic i Provincial de Barcelona ( Site 0501)

Barcelona, 08036, Spain

Location

Hospital Sanitas La Moraleja ( Site 0504)

Madrid, 28050, Spain

Location

Iv-Fr Reg Perinatal center State higher Educa inst Iv-Fr Nat Med University ( Site 0910)

Ivano-Frankivsk, 76018, Ukraine

Location

Medical Center Verum ( Site 0900)

Kyiv, 03040, Ukraine

Location

GI Institute of POG of NAMS of Ukraine ( Site 0905)

Kyiv, 03067, Ukraine

Location

City Clinical Hospital No. 9 ( Site 0901)

Kyiv, 04112, Ukraine

Location

Multiprofile medical center on the base of Odessa National Medical University ( Site 0908)

Odesa, 65023, Ukraine

Location

Communal not commercial institution. Ternopil City Community Hospital 2 ( Site 0903)

Ternopil, 46400, Ukraine

Location

Communal Nonprofit Enterprize Maternity Hospital 4 ( Site 0904)

Zaporizhzhya, 69065, Ukraine

Location

Communal Institution Maternity Hospital 3 ( Site 0909)

Zaporizhzhya, 69071, Ukraine

Location

Municipal Institution Zaporizhzhya Regional Clinical Hospital ( Site 0906)

Zaporizhzhya, 69071, Ukraine

Location

Related Publications (1)

• Arbelaez F, Joeng HK, Hussain A, Sunga S, Guan Y, Chawla A, Carmona F, Lines C, Mendizabal G. Randomized, controlled, proof-of-concept trial of gefapixant for endometriosis-related pain. Fertil Steril. 2025 Feb;123(2):280-288. doi: 10.1016/j.fertnstert.2024.09.013. Epub 2024 Sep 12.

  PMID: 39260540 RESULT

MeSH Terms

Interventions

Gefapixant; Naproxen

Intervention Hierarchy (Ancestors)

Naphthaleneacetic Acids; Naphthalenes; Polycyclic Aromatic Hydrocarbons; Hydrocarbons, Aromatic; Hydrocarbons, Cyclic; Hydrocarbons; Organic Chemicals; Polycyclic Compounds

Results Point of Contact

• Title: Senior Vice President, Global Clinical Development
• Organization: Merck Sharp & Dohme Corp.

ClinicalTrialsDisclosure@msd.com

1-800-672-6372

Study Officials

• Medical Director

  Merck Sharp & Dohme LLC

  STUDY DIRECTOR

Publication Agreements

• PI is Sponsor Employee: No
• Restriction Type: OTHER
• Restrictive Agreement: Yes

Study Design

• Study Type: interventional
• Phase: phase 2
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, INVESTIGATOR
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: August 17, 2018
• First Posted: August 31, 2018
• Study Start: September 11, 2018
• Primary Completion: June 30, 2020
• Study Completion: June 30, 2020
• Last Updated: November 4, 2024
• Results First Posted: July 7, 2021

Record last verified: 2024-10

Data Sharing

• IPD Sharing: Will share

Locations

NZ (2); US (30); ES (4); UA (9); AU (5); PL (9); PR (5); CL (5); RU (9)