Comparison of azathioprine, cyclophosphamide, and gold in treatment of rheumatoid arthritis.

Azathioprine, cyclophosphamide, and gold have been compared under double-blind conditions in the treatment of relatively early rheumatoid arthritis. Over 18 months the two "immunosuppressive" agents produced clinical improvement comparable to that achieved with gold, and they also facilitated a reduction in the dosage of corticosteroids and retarded radiological joint deterioration. Drug management was easiest with azathioprine. Cyclophosphamide was perhaps marginally the most effective drug but it produced azoospermia in males. If the long-term hazards of malignancy and mutagenesis prove to be acceptable then the anti-proliferative agents provide a useful alternative to gold therapy and can with advantage be given relatively early in the course of rheumatoid arthritis.