Leflunomide in active rheumatoid arthritis: a prospective study in daily practice

Br J Clin Pharmacol. 2004 Aug;58(2):201-8. doi: 10.1111/j.1365-2125.2004.02131.x.


Aims: We prospectively studied the efficacy, incidence of adverse drug reactions and withdrawal from leflunomide in an outpatient population with rheumatoid arthritis in a setting of care-as-usual.

Methods: In this prospective case series study, a standard dataset was collected from outpatient medical records, including patient and disease characteristics, data on leflunomide use and adverse drug reactions.

Results: During the study period 136 rheumatoid arthritis patients started leflunomide. Median (range) follow-up duration was 317 (11-911) days. Sixty-five percent of patients experienced at least one adverse drug reaction related to leflunomide. During follow-up 76 patients (56%) withdrew from leflunomide treatment, mainly because of adverse drug reactions (29%) or lack of efficacy (13%). The overall incidence density for withdrawal from leflunomide was 56.2 per 100 patient years. Complete data for calculating efficacy using a validated disease activity score on 28 joints (DAS(28)) was available for 48, 36, and 35% of patients at 2, 6, and 12 months follow-up, respectively. Within a 12-month period after start of leflunomide treatment 76% of the evaluable patients were classified as moderate or good responders according to the DAS(28) response criteria.

Conclusions: In the setting of care-as-usual rheumatoid arthritis patients starting leflunomide frequently experienced adverse drug reactions. More than half of the patients withdrew from leflunomide treatment within 1 year of starting leflunomide treatment, mainly because of adverse drug reactions.

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Antirheumatic Agents / adverse effects*
  • Arthritis, Rheumatoid / drug therapy*
  • Female
  • Follow-Up Studies
  • Humans
  • Isoxazoles / adverse effects*
  • Leflunomide
  • Male
  • Middle Aged
  • Prospective Studies
  • Treatment Outcome
  • Withholding Treatment


  • Antirheumatic Agents
  • Isoxazoles
  • Leflunomide