title: Leflunomide in active rheumatoid arthritis: a prospective study in daily practice.
abstract: OBJECTIVE
  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.
authors.affiliation: Department of Hospital Pharmacy and Clinical Pharmacology, Medical Centre Leeuwarden, Leeuwarden, The Netherlands. E.N.van.Roon@ZNB.nl
authors.forename: E N
authors.initials: EN
authors.lastname: Van Roon
authors.forename: T L Th A
authors.initials: TL
authors.lastname: Jansen
authors.forename: L
authors.initials: L
authors.lastname: Mourad
authors.forename: P M
authors.initials: PM
authors.lastname: Houtman
authors.forename: G A W
authors.initials: GA
authors.lastname: Bruyn
authors.forename: E N
authors.initials: EN
authors.lastname: Griep
authors.forename: B
authors.initials: B
authors.lastname: Wilffert
authors.forename: H
authors.initials: H
authors.lastname: Tobi
authors.forename: J R B J
authors.initials: JR
authors.lastname: Brouwers
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018501:Antirheumatic Agents / Q000009:adverse effects*; D001172:Arthritis, Rheumatoid / Q000188:drug therapy*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007555:Isoxazoles / Q000009:adverse effects*; D000077339:Leflunomide; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D016896:Treatment Outcome; D028761:Withholding Treatment
chemical_list: D018501:Antirheumatic Agents; D007555:Isoxazoles; D000077339:Leflunomide