We updated the design of this site on December 18, 2017. Learn more.
ClinicalTrials.gov Menu

A Four-Week Multicenter Study Evaluating the Safety and Efficacy of Gefapixant (AF-219/MK-7264) in Subjects With Osteoarthritis of the Knee

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details.
ClinicalTrials.gov Identifier: NCT01554579
Recruitment Status : Completed
First Posted : March 15, 2012
Results First Posted : March 1, 2017
Last Update Posted : May 17, 2017
Information provided by (Responsible Party):

March 12, 2012
March 15, 2012
September 23, 2016
March 1, 2017
May 17, 2017
March 31, 2012
November 30, 2013   (Final data collection date for primary outcome measure)
The Primary Efficacy Endpoint of This Study is the Weekly Average Daily NPRS (Average Pain) [ Time Frame: 2 Weeks ]
Subjects were instructed to select a number on a scale that best described their knee arthritis pain during the past 24 hours. The scale was between 0 and 10 where 0 was no pain and 10 was the worst possible pain. The scale was completed by telephone (an interactive voice response system [IVRS]) every evening before bedtime.
The primary efficacy endpoint of this study is change from Baseline of Question #1 of the WOMAC Osteoarthritis Index pain subscale (walking pain) [ Time Frame: 4 Weeks ]
Complete list of historical versions of study NCT01554579 on ClinicalTrials.gov Archive Site
  • WOMAC Scores [ Time Frame: 4 Weeks ]
    This is the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). This is a questionnaire that asks subjects to evaluate their pain, stiffness, and physical activities affecting their knee over the past 48 hours. Subjects evaluate their pain, stiffness and physical activities by selecting a number between 0 and 10 where 0 is no pain/no stiffness/no difficulty doing physical activities and 10 is extreme pain/extreme stiffness/extreme difficulty doing physical activities. The questionnaire was administered at Screening, Baseline and at the end of Week 4 by telephone (an interactive voice response system [IVRS]) before bedtime. The scores for each category are totaled (range is 0-100). A lower total score means less pain and a higher total score means greater pain.
  • SF-36 [ Time Frame: 4 Weeks ]
    The SF-36 (acute version 2) was a 36 question survey administered at Baseline and at the end of study or early termination (Week 4). The questionnaire contained numerous domain scores to evaluate physical function, mental function, general health, bodily pain, social functioning and vitality. The question of interest for the analysis was question #1 regarding walking pain. Scores range from 0 - 100. A lower score means decreased pain while walking and a higher score means increased pain while walking.
  • WOMAC Scores [ Time Frame: 4 Weeks ]
  • Daily Pain Scores [ Time Frame: 4 Weeks ]
  • Patient Global Assessment of Osteoarthritis [ Time Frame: 4 Weeks ]
  • Patient's and Clinician's Global Impression of Change [ Time Frame: 4 Weeks ]
  • Rescue medication usage [ Time Frame: 4 Weeks ]
  • Withdrawal for lack of efficacy [ Time Frame: 4 Weeks ]
  • SF-36 [ Time Frame: 4 Weeks ]
Not Provided
Not Provided
A Four-Week Multicenter Study Evaluating the Safety and Efficacy of Gefapixant (AF-219/MK-7264) in Subjects With Osteoarthritis of the Knee
Not Provided

The purpose of this study is to assess the efficacy of a single dose level of gefapixant (AF-219/MK-7264) in subjects with moderate to severe pain associated with osteoarthritis (OA) of the knee compared with placebo after 4 weeks of treatment.

The study will also assess the safety and tolerability, changes in physical function, stiffness, treatment response and health outcomes.

Subjects who satisfy entry criteria at Screening will enter the Washout Phase, discontinuing their current nonsteroidal anti-inflammatory drug (NSAID) therapy.

Up to 220 subjects who fulfill flare (and other entry) criteria will be randomized to gefapixant or placebo.

Subjects will complete Treatment Visits 1, 2, 3, and 4 weeks after starting study drug. At each Treatment Visit, subjects will undergo efficacy assessments and safety procedures. During the Washout and Treatment Phases subjects will complete the 'average pain' Numeric Pain Rating Scale (NPRS) and count of rescue medication used for the preceding 24 hours.

Subjects will return 2 weeks after their last Treatment Visit (for a Follow-Up Visit).

Phase 2
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary Purpose: Treatment
Osteoarthritis of the Knee
  • Drug: Gefapixant
    Other Names:
    • AF-219
    • MK-7264
  • Drug: Sugar Pill
  • Placebo Comparator: Sugar pill
    Intervention: Drug: Sugar Pill
  • Experimental: Gefapixant
    Intervention: Drug: Gefapixant
Not Provided

*   Includes publications given by the data provider as well as publications identified by ClinicalTrials.gov Identifier (NCT Number) in Medline.
November 30, 2013
November 30, 2013   (Final data collection date for primary outcome measure)

Inclusion Criteria:

  • Men or women
  • Women of child bearing potential must not be pregnant during the study and must use two forms of birth control
  • Men and their female partners must use two forms of birth control
  • Clinical and radiographic evidence of chronic knee osteoarthritis
  • An average NPRS score of >=5 and <=9 over a 4-7 day washout period of their previous osteoarthritis medications
  • Ambulatory
  • Have provided written informed consent
Sexes Eligible for Study: All
40 Years to 80 Years   (Adult, Senior)
Contact information is only displayed when the study is recruiting subjects
United States
AF219004 ( Other Identifier: Afferent Pharmaceuticals )
Not Provided
Not Provided
Afferent Pharmaceuticals, Inc.
Afferent Pharmaceuticals, Inc.
Not Provided
Not Provided
Afferent Pharmaceuticals, Inc.
April 2017

ICMJE     Data element required by the International Committee of Medical Journal Editors and the World Health Organization ICTRP