Open-label Trial to Check the Safety and Tolerability of RTX-GRT7039 Injections for Pain Associated With Osteoarthritis of the Knee

Recruitment Status
COMPLETED - HAS RESULTS
(See Contacts and Locations)Verified January 2026 by Grünenthal GmbH
Sponsor
Grünenthal GmbH
Information Provided by (Responsible Party)
Grünenthal GmbH
Clinicaltrials.gov Identifier
NCT05377489
Other Study ID Numbers:
KF7039-03
First Submitted
May 11, 2022
First Posted
May 16, 2022
Results First Posted
November 17, 2025
Last Update Posted
March 11, 2026
Last Verified
January 2026

ClinicalTrials.gov processed this data on February 2026. Link to the current ClinicalTrials.gov record .

History of Changes

Study Details

Study Description

This trial comprises a total observation period of up to 78 weeks.

Condition or DiseaseIntervention/Treatment
Osteoarthritis
Drug: RTX-GRT7039

Study Design

Study TypeInterventional
Actual Enrollment714 participants
Design AllocationN/A
Interventional ModelSingle Group Assignment
MaskingNone (Open Label)
Primary PurposeTreatment
Official TitleA Single-arm, Open-label, Phase III Trial to Evaluate the Safety and Tolerability of Intra-articular Injections of RTX-GRT7039 in Subjects With Moderate to Severe Pain Associated With Osteoarthritis of the Knee.
Study Start DateSeptember 14, 2022
Actual Primary Completion DateMay 14, 2025
Actual Study Completion DateMay 14, 2025

Groups and Cohorts

Group/CohortIntervention/Treatment
RTX-GRT7039
Participants will receive injections of RTX-GRT7039 into either the index knee (affected knee or in case of bilateral OA the knee with highest pain intensity), or each of both knees up to Week 52.
Drug: RTX-GRT7039
RTX-GRT7039 monoarticular injections or bilateral intra-articular injections.

Outcome Measures

Primary Outcome Measures
  1. Number of Participants With Treatment-Emergent Adverse Events (TEAEs)
  2. Number of Participants With TEAEs Leading to Study Discontinuation
Secondary Outcome Measures
  1. Number of Participants With TEAEs Representing Structural Changes as Assessed by Imaging Methods
  2. Change From Baseline in WOMAC Pain Subscale Score
    The WOMAC pain subscale will be assessed using an 11-point numerical rating scale (NRS), where 0= no pain and 10=worst pain.

Eligibility Criteria

Ages Eligible for Study(Adult, Older Adult)
Sexes Eligible for StudyAll
Accepts Healthy VolunteersNo
Inclusion Criteria
The participant has given written informed consent to participate.
The participant is 18 years of age or older at the Screening Visit.
The participant has a diagnosis of osteoarthritis of the knee based on American College of Rheumatology criteria and functional capacity class of I to III.
There is a documented history indicating that participant has insufficient pain relief with previous Standard of Care.
Exclusion Criteria
The participant has past joint replacement surgery of the index knee.
The participant has a history of significant trauma or surgery (e.g., open or arthroscopic) to the index knee within 12 months of Screening.
The participant has periarticular pain at the index knee from any cause other than osteoarthritis, including referred pain, bursitis, tendonitis.
The participant has clinical hip osteoarthritis on the side of the index knee.
The participant has a history of osteonecrosis, subchondral insufficiency fracture, atrophic osteoarthritis, rapidly progressing osteoarthritis (RPOA) Type I or Type II,pathologic fracture, primary or metastatic tumor, or joint infection in the index knee.
The participant has significant malalignment of anatomical axis (medial angle formed by the femur and tibia) of the target knee (varus \>10°, valgus \>10°) by radiograph as assessed by independent Central Readers at Screening Visit.
The participant has other conditions that could affect trial endpoint assessments of the index knee.
The participant has current clinically significant disease(s) or condition(s) that may affect safety assessments, or any other reason which may preclude the participant's participation for the full duration of the trial.
The participant has a history of hypersensitivity to resiniferatoxin (RTX) or any similar component (capsaicin, chili peppers).
The participant is currently participating or was participating in another investigational drug trial within 3 months prior to the Screening Visit.
The participant is an employee of the investigator or trial site, with direct involvement in the proposed trial or other trials under the direction of that investigator or trial site or is a family member of the employees or the investigator. The non-index knee is not eligible for treatment in the trial, if any of the knee-related exclusion criteria applies to the non-index knee.

Contacts and Locations

Sponsors and CollaboratorsGrünenthal GmbH
Locations
Arizona Arthritis and Rheumatology Associates (AARA) P.C | Glendale Arizona, United States, 85306Elite Clinical Studies, LLC | Phoenix Arizona, United States, 85018Orange County Research Institute | Anaheim California, United States, 92801Acclaim Clinical Research, Inc. | San Diego California, United States, 92120Westlake Medical Research | Thousand Oaks California, United States, 91360Progressive Medical Research | Port Orange Florida, United States, 32127Gulfcoast Research Institute | Sarasota Florida, United States, 34232Palm Beach Research Center | West Palm Beach Florida, United States, 33409North Georgia Clinical Research | Woodstock Georgia, United States, 30189Injury Care Research | Boise Idaho, United States, 83713Chicago Clinical Research Institute Inc. | Chicago Illinois, United States, 60607OrthoIndy, Inc. | Greenwood Indiana, United States, 46143University Of Kansas Medical Center | Kansas City Kansas, United States, 66160Neuroscience Research Center, LLC | Overland Park Kansas, United States, 66210Clinical Pharmacology Study Group | Worcester Massachusetts, United States, 01605Oakland Medical Research Center | Troy Michigan, United States, 48085Excel Clinical Research | Las Vegas Nevada, United States, 89109Las Vegas Clinical Trials, LLC | North Las Vegas Nevada, United States, 89030Drug Trials America | Hartsdale New York, United States, 10530M3-Emerging Medical Research, LLC | Durham North Carolina, United States, 27704M3-Emerging Medical Research, LLC | Raleigh North Carolina, United States, 27704University Orthopedics Center | State College Pennsylvania, United States, 16801Coastal Carolina Research Center | Mt. Pleasant South Carolina, United States, 29464Coastal Carolina Research Center | North Charleston South Carolina, United States, 29405Accellacare-Knoxville | Knoxville Tennessee, United States, 37912Tekton Research, Inc. | San Antonio Texas, United States, 78229Wasatch Clinical Research | Salt Lake City Utah, United States, 84107UMHAT Eurohospital Plovdiv OOD | Plovdiv , Bulgaria, 4000Medical Centre Artmed | Plovdiv , Bulgaria, 4002MHAT Kaspela EOOD | Plovdiv , Bulgaria, 4002UMHAT Pulmed | Plovdiv , Bulgaria, 4002University Multiprofile Hospital For Active Treatment Pulmed OOD | Plovdiv , Bulgaria, 4002Medical Centre N. I. Pirogov EOOD | Sofia , Bulgaria, 1000MHAT St Iv. Rilski | Sofia , Bulgaria, 1612UMBAL Sveti Ivan Rilski EAD | Sofia , Bulgaria, 1612Synexus Medical Center Sofia | Sofia , Bulgaria, 1784Multi-Profile District Hospital for Active Treatment Dr. Stefan Cherkezov | Veliko Tarnovo , Bulgaria, 5000Fukuoka University Hospital | Fukuoka Fukuoka, Japan, 8140180Medical Corporation Kouhoukai Takagi Hospital | Okawa-shi Fukuoka, Japan, 831-0016Hakodate Central General Hospital | Hakodate Hokkaido, Japan, 040-8585Saiseikai Kanagawaken Hospital | Yokohama Kanagawa, Japan, 221-0821Otakibashi Orthopedic Clinic | Shinjuku-ku Tokyo, Japan, 169-0073Saitama Medical Center | Saitama , Japan, 350-8550Uniwersytecki Szpital Kliniczny im. Jana Mikulicza-Radeckiego we Wroclawiu | Wroclaw Lower Silesian Voivodeship, Poland, 50-556Centrum Medyczne 4M Plus | Krakow Malopolska, Poland, 31141ETG Warszawa | Warsaw Masovian Voivodeship, Poland, 02-777ClinicMed Badurski I Wspolnicy Spolka Jawna | Bialystok , Poland, 15-879ClinicMed Daniluk, Nowak Spolka komandytowa | Bialystok , Poland, 15-879Zaklad Opieki Zdrowotnej w Boleslawcu | Bolesławiec , Poland, 59-700Centrum Kliniczno | Elblag , Poland, 82-300NZOZ Medi Spatz | Gliwice , Poland, 44-100PZU Zdrowie S.A. Oddzia¿ Centrum Medyczne Artimed w Kielcach | Kielce , Poland, 25-017Centrum Medyczne Semper fortis | Krakow , Poland, 31-141Centermed Krakow Sp. z o.o. | Krakow , Poland, 31-530Nzoz Centermed Krakow, Szpital I Przychodnia | Krakow , Poland, 31-530ETYKA Osrodek Badan Klinicznych | Olsztyn , Poland, 10-117Medyczne Centrum Hetmanska Indywidualna Specjalistyczna Praktyka Lekarska Dr Hab Piotr Leszczynski | Poznan , Poland, 60-218Medyczne Centrum Hetmanska | Poznan , Poland, 60-218RCMed Oddzial Sochaczew | Sochaczew , Poland, 96-500RCMed Piotr Opadczuk | Sochaczew , Poland, 96-500Lubelskie Centrum Diagnostyczne | Świdnik , Poland, 21040ETG Warszawa | Warsaw , Poland, 02-677Europejskie Centrum leczenia Chorob Cywilizacyjnych | Warsaw , Poland, 02-777ETG Warszawa | Warsaw , Poland, 02-793Wojewodzki Szpital Zespolony W Kielcach | Kielce Świętokrzyskie Voivodeship, Poland, 25-736Spitalul Judetean Caracal | Caracal Olt, Romania, 235200SC Medicali's SRL | Timișoara Timiș County, Romania, 300362SC Medaudio-Optica SRL | Râmnicu Vâlcea Vâlcea County, Romania, 240762Centrul Medical de Diagnostic si Tratament Ambulatoriu Neomed SRL | Brasov , Romania, 500283SC Centrul Medical Sana SRL | Bucharest , Romania, 011025Spitalul Clinic Sf. Maria | Bucharest , Romania, 011172Spital Clinic Dr I Cantacuzino | Bucharest , Romania, 020475SC Policlinica CCBR SRL | Bucharest , Romania, 030463Sf. Maria Hospital | Bucharest , Romania, 11172Tread Research | Parow Cape Town, South Africa, 7500Tygerberg hospital | Parow Cape Town, South Africa, 7500Josha Research | Bloemfontein Free State, South Africa, 9301Welkom Clinical Trial Centre | Welkom Free State, South Africa, 9460Worthwhile Clinical Trials | Benoni Gauteng, South Africa, Midrand Medical Centre | Halfway House Gauteng, South Africa, 1685Lakeview Hospital | Johannesburg Gauteng, South Africa, 1500Global Clinical Trials | Pretoria Gauteng, South Africa, 0001University of Pretoria | Pretoria Gauteng, South Africa, 0002Roodepoort Medicross Clinical Research Centre | Roodepoort Gauteng, South Africa, 1724Sandton Medical Research (Newtown CRC) | Sandton Gauteng, South Africa, 2196Clinresco Centres (Pty) Ltd. | Kempton Park Johannesburg, South Africa, 1619Synapta Clinical Research Center | Durban KwaZulu-Natal, South Africa, 4001Dr Zubar Fazal Ahmed Vawda MD | Durban KwaZulu-Natal, South Africa, 4091Precise Clinical Solutions | Durban KwaZulu-Natal, South Africa, 4092Aliwal Shoal Medical Centre | eMkhomazi KwaZulu-Natal, South Africa, 4170Medicross Langeberg Medical & Dental Centre | Kraaifontein Western Cape, South Africa, 7570Medicross Langeberg Medical & Dental Centre | Kraaifontein Western Cape, South Africa, 7572Arthritis Clinical Research Centre | Cape Town , South Africa, 7405Accellacare Yorkshire | Shipley Yorkshire, United Kingdom, BD18 3SAAccellacare Warwickshire | Coventry , United Kingdom, CV3 4FJChapel Allerton Hospital - Leeds Teaching Hospitals NHS Trust | Leeds , United Kingdom, LS7 4SA
Study Documents (Full Text)
Documents provided by Grünenthal GmbH: Study Protocol and Statistical Analysis Plan  October 8, 2025