A high dose (up to 200 mg) tolerance and efficacy study of intra-articular rimexolone (Org 6216) in rheumatoid synovitis of the knee.

Twenty patients with classical or definite rheumatoid arthritis received one intra-articular injection of 40, 80, 120, 160 or 200 mg rimexolone (Org 6216) into one knee joint. Rimexolone was well tolerated and the incidence of side-effects was low. A beneficial effect was sustained over the study period of 94 days and a long-lasting effect was observed in 84% of the patients after one year and in 79% after 2 years. Safety parameters remained unaffected. Individual changes in adrenal response to ACTH and morning cortisol levels did not correlate with the dose or with serum levels of rimexolone. Rimexolone showed linear kinetics. The mean residence time in the intra-articular depot was 44 days (SD +/- 53) with a median of 26 days. Ninety percent was absorbed after 4 months. Outside the intra-articular depot the mean residence time was less than 0.1 days.