Longterm prospective studies (several of greater than 5 years' duration) report sustained efficacy with low dose weekly methotrexate. A "steroid-sparing" effect has been noted with methotrexate in 2 of the studies. Of 230 patients enrolled in prospective studies, only 8% stopped therapy due to toxicity and 3% due to lack of efficacy. Life table analysis projected that 63% of these patients would receive therapy for 6 years. Even though adverse experiences were frequent, serious reactions have been rare in the published studies.