RT Journal Article SR Electronic T1 Efficacy of topical diclofenac diethylamine gel in osteoarthritis of the knee. JF The Journal of Rheumatology JO J Rheumatol FD The Journal of Rheumatology SP 2384 OP 2392 VO 32 IS 12 A1 Fritz U Niethard A1 Morris S Gold A1 Gail S Solomon A1 Jiun-Min Liu A1 Markus Unkauf A1 Helmut H Albrecht A1 Francois Elkik YR 2005 UL http://www.jrheum.org/content/32/12/2384.abstract AB OBJECTIVE: To assess the efficacy and safety of topical diclofenac diethylamine gel, 1.16%, 4 g applied qid for 3 weeks to relieve the symptoms of osteoarthritis (OA) of the knee. METHODS: Patients with OA of the knee washed out their OA medications for at least 5 drug half-lives. Patients with adequately high baseline pain scores were randomized to apply either double-blind active or placebo gel for 3 weeks. Acetaminophen (up to 2 g/day) was supplied as rescue medication. In a diary, patients recorded compliance to dosing and use of rescue medication and assessed daily pain on movement, spontaneous pain, and pain relief. At weekly site visits, patients completed the Western Ontario and McMaster (WOMAC) Osteoarthritis Index Questionnaire, which includes assessment of pain, stiffness, and physical function, and assessed pain intensity "right now." At the final visit, a global assessment of treatment efficacy was completed. RESULTS: Of 238 randomized patients, 237 were included in the intent to treat efficacy analysis. Treatments differed significantly for daily pain on movement at Day 5, and continued on most days through end of study. Peak differences were achieved in the second week. On the primary outcome, average pain on movement over Days 1-14, diclofenac gel was significantly superior to placebo gel. Scores for all 3 WOMAC indices for diclofenac gel treatment were significantly superior to placebo at Weeks 2 and 3. A significant difference was achieved on pain intensity "right now" at all 3 weeks. At the end of the study, patients rated diclofenac gel as significantly more effective in treating the pain of OA of the knee (p = 0.03) compared to placebo. There were no safety issues concerning adverse events or laboratory values. CONCLUSION: Diclofenac gel was effective and safe for relief of symptoms of OA of the knee over 3 weeks of dosing.