Slowing of disease progression in rheumatoid arthritis patients during long-term treatment with leflunomide or sulfasalazine

Radiographic disease progression with leflunomide and sulfasalazine treatme nt was assessed in rheumatoid arthritis patients in a double-blind trial th at was placebo controlled for the first 6 months. Completers at 6 months op ted to continue on 12- and 24-month double-blind extensions: patients in th e placebo group were switched to sulfasalazine. Changes in Larsen scores we re assessed in evaluable patient cohorts at 6 (n = 228), 12 (n = 136), and 24 (n = 65) months. Changes in Larsen scores and erosive joint counts with leflunomide and sulfasalazine at 6 months showed significantly less radiogr aphic progression than placebo. Sustained retardation of radiographic progr ession was seen in the 24-month intent-to-treat cohorts (Delta Larsen score s: leflunomide -0.07, sulfasalazine -0.03). Changes in erosive joint counts within the 24-month leflunomide cohort suggest halting of disease progress ion for patients who continued in the study for 2 years (leflunomide -0.92, sulfasalazine 0.80). Leflunomide was well tolerated with no unexpected adv erse events during the 2-year period. This study demonstrates that slowing of disease progression with leflunomide, observed as early as 6 months, is maintained long term in patients who complete 2 years of treatment.