Recruiting

Observational Study

Sponsor:

UCLA

Code:

NCT06574191

Conditions

Knee Osteoarthritis

Eligibility Criteria

Sex: All

Age: 50+

Healthy Volunteers: Not accepted

Interventions

Topical Diclofenac gel 1%

Study Details

Brief summary:

The goal of this clinical trial is to understand the patient and clinic visit characteristics that affect health outcomes for individuals with knee osteoarthritis (OA) pain using topical diclofenac gel. The main questions it aims to answer are:

  • What baseline patient characteristics predict response to topical diclofenac?
  • Does patient physiology during the study visit predict response to topical diclofenac?
  • Do study visit characteristics predict response to topical diclofenac?

Participants will:

  • attend 2 study visits to complete study questionnaires and have blood drawn
  • apply topical diclofenac to their knee for 8 weeks
  • complete biweekly questions about knee pain and diclofenac use between study visits

Conditions

Knee Osteoarthritis

Study ID

NCT06574191

Start date

Jan 29, 2025

Status verified date

Mar, 2026

Completion date

Jan 27, 2028

Anticipated

Primary completion date

Jan 27, 2028

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: All

Age: 50+

Healthy Volunteers: Not accepted

Inclusion Criteria:

  • English-speaking
  • 50 years of age or older
  • Radiographically confirmed knee OA of K/L grade 2 or higher within the past 2 years
  • Knee pain at least 15 days/month.
  • Average worst daily pain 3/10 or higher over a two-week period.

Exclusion Criteria:

  • Medical contraindication to taking NSAIDs such as: history of coronary artery bypass graft, myocardial infarction, coronary artery stent placement, or stroke within the past 6 months; systolic heart failure with ejection fraction <45%; chronic kidney disease stage ≥4; severe gastrointestinal bleed or stomach ulcer within the past 6 months; current pregnancy; cirrhosis; currently taking blood thinners (aspirin 81 mg daily is okay); allergy to NSAIDs or aspirin; or any other medical contraindication to using topical NSAIDs.
  • Inflammatory arthritis
  • Partial or total knee replacement of the index knee
  • Recent therapeutic injection of the index knee (less than 12 weeks)
  • Planned knee/lower limb surgery during the two-month study period
  • Active cancer treatment not in remission or life expectancy less than 6 months
  • Inability to provide informed consent (e.g. dementia)
  • Current use of topical or oral NSAIDs more than 3 days per week.
  • Inability to receive text messages or emails to complete questionnaires between study visits.
  • Unable to follow the study protocol.

Study Design

Enrollment

220 participants

Anticipated

Intervention Model

Single group

Primary purpose

Basic Science

Interventions and Outcome Measures

Arms

experimental: Diclofenac

All study participants receiving topical diclofenac gel 1%. Participants will be instructed to apply 4 grams of the gel to the index knee at least once per day, and up to 4 times per day, for 8 weeks.

Interventions

Topical Diclofenac gel 1%

Topical NSAID

Primary outcome measure

  • Knee Pain [ Time Frame: 8 weeks ]
  • Knee Function [ Time Frame: 8 weeks ]

Central Contacts and Locations

Central contacts

Maya Porter

916-734-4216mtporter@ucdavis.edu

Michelle Dossett, MD, PhD

916-734-5367mdossett@ucdavis.edu

Locations

University of California Davis Health

Recruiting

Sacramento, California, United States, 95817

Contacts

Michelle Dossett, MD, PhD, MPH

916-734-5367mdossett@ucdavis.edu

More Information

Sponsor

University of California, Davis

Last update posted

Mar 30, 2026

Last verified

Mar, 2026

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-10. This information was provided to ClinicalTrials.gov by University of California, Davis on 2026-03-30.