Multicentre double-blind comparison of sustained action formulations of tiaprofenic acid and indomethacin in osteoarthritis.

In a randomised double-blind, multicentre, crossover study, the short term efficacy and tolerance of a sustained action preparation of tiaprofenic acid 600 mg once daily was compared with sustained release indomethacin 75 mg once daily in 98 patients with osteoarthritis. After a minimum washout period of 3 days, patients were randomly allocated to receive each treatment in turn for a period of 4 weeks. There were no significant differences between the 2 treatments in the clinical assessments of pain level, duration of morning stiffness, articular index and functional impairment performed at the end of each treatment period. High pain levels on movement were reduced by both treatments, and reduction was also seen in night pain, where initial levels were lower. There was no significant difference between the number of patients who reported side effects on the 2 treatments. 37 patients (39%) reported 49 side effects while taking sustained release tiaprofenic acid, and 35 patients (37%) reported 53 side effects while taking sustained release indomethacin. Daily diary cards showed that both treatments provided improvements in duration of morning stiffness and in pain relief. Thus sustained action tiaprofenic acid and sustained release indomethacin were shown to be equally well tolerated and efficacious.