Leflunomide EfficAcy Response Related to Dosing Regimen in Early Rheumatoid Arthritis

To assess the efficacy response rate at 3-months of two dosing regimen of leflunomide in DMARDs-naive patients presenting an early-RA using American College of Rheumatology 20% response rate. To assess the clinical efficacy at 1-month and 3-month using complementary efficacy criteria (ACR 50, ACR 70, DAS 28) in each group of treatment, To assess the clinical and biological safety using standard blood monitoring, TEAED and SAE in each group of treatment, To evaluate treatment modifications; particularity leflunomide and concomitant use of AINS and corticoids.