Clinical Trial Finder

Inclusion Criteria:

• - Male or female, age greater than 40 years, with no racial/ethnic restrictions.

• - Meet American College of Rheumatology (ACR) criteria for knee osteoarthritis (OA) - Knee pain most days of the week for the past month.

• - Must have average pain score for the week prior to baseline of ≥ 4 (on 1 to 10 numeric rating scale (NRS)) - Must complete pain ratings on at least 4 out of 7 days prior to baseline.

• - Must be able to speak English and be willing to read and understand instructions as well as questionnaires.

• - Must be in generally stable health.

• - Must be able to return for all clinic visits.

• - Must sign an informed consent document after complete explanation of the study documenting that they understand the purpose of the study, procedures to be undertaken, possible benefits, potential risks, and are willing to participate.

Exclusion Criteria:

• - Evidence of rheumatoid arthritis, ankylosing spondylitis, other inflammatory arthropathy.

• - Functional class IV.

• - Significant other medical disease such as uncontrolled hypertension, unstable diabetes mellitus, congestive heart failure, coronary or peripheral vascular disease, chronic obstructive lung disease, liver disease (LFT's >3x ULN) or malignancy.

• - Current us of recreational drugs or history (in last 12 months) of alcohol or drug abuse.

• - High dose opioid prophylaxis, as defined as > 50mg morphine equivalent/day.

• - Any medical condition in that in the investigator's judgement may prevent the individual from completing the study or put the individual at undue risk.

• - In the judgement of the investigator, unable or unwilling to follow protocol instructions.

• - Intra-axial implants (e.g., spinal cord stimulators or pumps) - All exclusion criteria for magnetic resonance (MR) safety: any metallic implants, brain or skull abnormalities, tattoos on large body parts, and claustrophobia.

• - Pregnancy.

• - Chronic neurologic conditions, e.g., Parkinson's.

• - Chronic renal disease.

• - Renal insufficiency (creatine >1.5 mg/dl) - Previous history of peptic ulcer of GI bleeding.

• - Use of anticoagulants or platelet inhibitors other than aspirin (ASA) at ≤325 mg/day.

• - Allergy to sulfonamide drugs, duloxetine or acetaminophen.

• - Acute myocardial infarction or coronary artery bypass graft surgery, in the past 12 months.

• - Recent injection into the index knee of hyaluronic acid or other substance in the last 6 months, or steroid in the last 90 days.

- Severe lactose intolerance

This longitudinal study will screen and enroll 180 participants diagnosed with knee osteoarthritis at Northwestern University Feinberg School of Medicine. The study will last for about 20 weeks' duration with a repeat-treatment design. An equal number of participants (60 per group) will be randomly assigned in a 1:1:1 ratio, stratified by sex and current opioid use, to one of three treatment groups after they qualify to enter the study. The treatment groups will celecoxib (200 mg qd), duloxetine (60 mg qd, with an initial and final 7-day titration at 30 mg qd), or matching placebo (one capsule qd). This aim of this study is to identify specific biomarkers in individual people with knee osteoarthritis pain that will allow definition of responder phenotypes distinct for different therapeutic interventions.

Arms

Active Comparator: Duloxetine

Duloxetine 60mg tablet, daily (with an initial and final 7-day titration at 30 mg, daily)

Active Comparator: Celecoxib

Celecoxib 200 mg tablet, daily

Placebo Comparator: Placebo

Matching placebo tablet, daily

Interventions

Drug: - Duloxetine

60 mg, oral

Drug: - Celecoxib

200 mg, oral

Drug: - Placebo

Matching placebo, oral