This trial is active, not recruiting.

Conditions osteoarthritis, chronic pain
Treatment phenotype assessment
Phase phase 4
Sponsor University of Michigan
Collaborator National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS)
Start date September 2011
End date November 2015
Trial size 70 participants
Trial identifier NCT01377038, 1K23AR060241-01, 2011 HUM00044644, UL1RR024986


The primary objective of this study is to evaluate the relative efficacy of a centrally-acting analgesic (duloxetine) versus a peripherally acting analgesic (topical diclofenac) for pain and associated symptom management in knee osteoarthritis. Secondary objectives include the determination of which self-report and experimental pain measures best differentiate those who respond better to duloxetine than diclofenac.

United States No locations recruiting
Other countries No locations recruiting

Study Design

Allocation randomized
Endpoint classification efficacy study
Intervention model crossover assignment
Masking double blind (subject, caregiver, investigator, outcomes assessor)
Primary purpose treatment
(Active Comparator)
Phenotype assessment prior to and after treatement with duloxetine 20-30 mg oral daily for eight weeks.
phenotype assessment
Quantitative sensory testing and patient reported outcome measures used to assess patient pain phenotype
(Active Comparator)
Phenotype assessment prior to and after treatment with topical diclofenac four times daily
phenotype assessment
Quantitative sensory testing and patient reported outcome measures used to assess patient pain phenotype

Primary Outcomes

time frame: One month

Eligibility Criteria

Male or female participants at least 50 years old.

Inclusion Criteria: - Diagnosed with knee osteoarthritis as defined by American College of Rheumatology (ACR) criteria - Males and females age greater than 50 years at time of screening Exclusion Criteria: - History of chronic kidney disease or moderate to severe hepatic impairment - History of anemia - Allergy or intolerance of drug intervention - Inability to participate in outcome measures

Additional Information

Official title Central Pain Mechanisms in Osteoarthritis: A Randomized, Double-blind, Crossover Study to Evaluate the Effectiveness of Topical Diclofenac Versus Duloxetine for Chronic Osteoarthritis Pain
Principal investigator Kristine Phillips, MD, PhD
Description This is a randomized, blinded, crossover, controlled study design comparing duloxetine and topical diclofenac for osteoarthritis pain. The study cohort will be individuals who have a confirmed diagnosis of knee osteoarthritis. Subjects will be randomized only after all entry criteria have been met. These individuals will be evaluated at baseline, and then followed longitudinally following enrollment.
Trial information was received from ClinicalTrials.gov and was last updated in June 2015.
Information provided to ClinicalTrials.gov by University of Michigan.