In a double-blind study 80 patients with active rheumatoid arthritis in slightly progressed state, who had not received systemic therapy, were treated with niflumic acid and indometazin in doses of 1000 mg resp. 100 mg per day for a period of 6 months. The investigation showed good results in the patients treated with niflumic acid. In particular were observed relief of pain, shortening of morning stiffness, improvement of grip-strength, decrease of sedimentation rate. In a number of cases an assuage of the basic disease was reached which was almost equal to remission. In some aspects niflumic acid was more effective than indometazin. Of particular value are the good tolerance and the lack of sideeffects subjectively as well as objectively. Niflumic acid is a particular suitable non-steroid containing preparation for a broad range of medical applications.