Efficacy and safety of diacerein in osteoarthritis of the knee - A double-blind, placebo-controlled trial

Objective, To evaluate the efficacy and safety of diacerein, a drug with in terleukin-lp-inhibitory activity in vitro, in patients with knee osteoarthr itis (OA), Methods, A total of 484 patients fulfilling the American College of Rheumat ology criteria for knee OA were enrolled in this 16-week, randomized, doubl e-blind, placebo-controlled, parallel study group with 3 diacerein dosages of 50 mg/day, 100 mg/day, and 150 mg/day (administered twice daily). Results. In the intent-to-treat population, 100 mg/day diacerein (50 mg twi ce daily) was significantly superior (P < 0.05) to placebo using the primar y criterion (visual analog scale [VAS] assessment of pain on movement), Sig nificant improvement (P < 0.05) was also observed for the secondary criteri a, which included the Western Ontario and McMaster Universities OA Index (W OMAC), the WOMAC subscores, and the VAS assessment of handicap, In patients treated with diacerein dosages of 50 mg/day and 150 mg/day, favorable but not significant results were observed for the primary criterion. The best d aily dosage of diacerein, calculated from the effect on the VAS assessment of pain on movement, was 90.1 mg, In the per-protocol population, the analy sis of the primary criterion showed significant dose-dependent differences (P < 0.05) between each of the 3 diacerein dosages and the placebo, No diff erences were observed among the 3 diacerein groups. A significantly higher incidence (P < 0.05) of adverse events (AEs), as well as a higher rate of d ropoout due to AEs, was observed in patients treated with 150 mg/day diacer ein versus those treated with placebo, 50 mg/day diacerein, or 100 mg/day d iacerein, Mild-to-moderate transient changes in bowel habits were the most frequent AEs, increasing with the dosage, Conclusion, Diacerein, a drug for the treatment of QA, was shown to be an e ffective treatment for symptoms in patients with knee OA, Taking into accou nt both efficacy and safety, the optimal daily dosage of diacerein for pati ents with knee OA is 100 mg/day (50 mg twice daily).