Efficacy and safety of etodolac-paracetamol fixed dose combination in patients with knee osteoarthritis flare-up: a randomized, double-blind comparative evaluation

To evaluate the efficacy and safety of etodolac-paracetamol combination in comparison with etodolac alone in patients with knee osteoarthritis (OA) flare-up.

In this double-blind, double-dummy, randomized, comparative, multicentric, parallel group study, 220 patients of either sex in the age range of 40 to 70 years with an OA flare-up were randomized either to etodolac (300 mg)-paracetamol (500 mg) combination or etodolac (300 mg) alone twice a day for 10 days. Efficacy outcomes were an average daily pain intensity score on 11-point visual analog scale, Western Ontario and McMaster score (WOMAC), and Lequesne Severity Index; total pain relief score at 30 minutes, 1, 2, and 4 hours after first-dose administration; OA flare-up symptoms resolution; patient's and investigator's overall assessment of study treatments.

Etodolac-paracetamol was significantly superior to etodolac alone in reducing pain intensity (P<0.001), achieving pain relief (P<0.05) during the first 4 hours after the study dose administration, and resolution of the clinical signs and symptoms of OA flare-up such as morning stiffness, swelling/inflammation, and erythema. The combination showed significantly greater improvement in WOMAC scores and Lequesne Severity Index (P<0.001) than in etodolac monotherapy. Peak pain intensity difference over a period of 10 days was also significantly (P<0.001) higher in combination-treated patients compared with monotherapy-treated patients. The combination had significantly better patient's and investigator's global efficacy assessment (P=0.001). Both treatments were well tolerated and safe in patients with OA flare-up.

For the treatment of painful OA flare-ups, the etodolac-paracetamol combination can offer improved clinical outcomes by targeting multiple pain pathways. The results of the current study show that etodolac-paracetamol is more effective in the treatment of OA flare-up than etodolac alone.