Diftalone: a new non-steroidal anti-inflammatory agent: comparative study with phenylbutazone in the treatment of rheumatoid arthritis.

A double-blind study was carried out to compare the effectiveness and tolerability of diftalone and phenylbutazone in thirty patients with classical or definite rheumatoid arthritis, randomly distributed between the two treatment groups. Both drugs were administered according to a progressively decreasing daily dosage schedule: 1,000 mg during the 1st week; 750 mg the 2nd week and 500 mg from the 3rd week on for diftalone; 400 mg, 300 mg, and 200 mg daily for the 1st, 2nd and from the 3rd week on respectively for phenylbutazone. The study lasted twelve weeks. The clinical controls and laboratory tests were performed weekly up to the 8th week, while the final evaluation was made at the end of the 3rd month. Twelve patients in the group receiving diftalone and fourteen in the phenylbutazone group completed the trial. Clinical improvement was observed in both groups. Effectiveness was somewhat more evident in the diftalone group. Tolerability was acceptable for both drugs, althoug the diftalone patients showed less frequent and intense side-effects than those treated with phyenylbutazone. No significant differences were found as regards the laboratory parameters, except a significant fall of the E.S.R. (less than 0-05) in the diftalone group. Diftalone seems to be an effective and safe anti-inflammatory agent in the treatment of rheumatoid arthritis.