ADALIMUMAB (HUMIRA®) IS EFFECTIVE IN TREATING PATIENTS WITH RHEUMATOID ARTHRITIS WHO PREVIOUSLY FAILED INFLIXIMAB TREATMENT

Background: Limited experience is available on the use of one TNF-antagonist in the treatment of rheumatoid arthritis (RA) following unsuccessful treatment with a previous biologic.Objectives: To investigate the safety and efficacy of adalimumab administered to patients with RA who had failed prior treatment with infliximab.Methods: Patients with long-standing, moderate to severe RA who had terminated infliximab therapy because of lack or loss of efficacy and/or intolerance were eligible to participate. Patients were treated with adalimumab sc 40 mg every other week. Follow-up visits for safety and efficacy monitoring were scheduled at 2, 8, and 16 weeks. Adalimumab responders were allowed to continue treatment for 56 weeks.Results: A total of 41 patients with RA (88% female, mean age 55 years) who had previously failed infliximab participated in this study. Mean baseline disease characteristics included: duration of RA, 12 yrs; 5.4 prior DMARDs, including infliximab; TJC28, 15; SJC28, 8; DAS28, 6.1; and HAQ, 1.85. Patients had been treated with infliximab for a mean of 17 months (range 3-67 months) and a median of 13 months. Reasons for infliximab discontinuation included lack of efficacy (n=15, 37%), loss of efficacy after initial response (n=21, 51%), and drug intolerance (n=7, 17%) (categories not mutually exclusive). Of the 41 patients treated enrolled, 37 had completed 16 weeks of adalimumab treatment and their data were available for safety and efficacy analysis (completer analysis). While on adalimumab therapy, 19 of 37 (51%) of the patients received concomitant MTX. Twenty-one of 37 (57%) had a decrease in DAS28 of ≥1.2 (maximum change –4.7) at week 16.Adalimumab was well-tolerated. Four patients discontinued treatment prematurely. One patient treated previously with infliximab for 5 years developed a non-Hodgkin''s lymphoma 3 weeks after enrolling in the study. The other 3 patients withdrew because of RA flare, skin rash, and injection site reactions, respectively. 16-Wk Efficacy: Patients Treated with Adalimumab Following Infliximab Withdrawal Efficacy Parameters All reasons (N=37) No response to infliximab (N=13) Loss of response to infliximab (N=19) Infliximab intolerance (N=5) ACR20 (%) 49 33 61 40 ACR50 (%) 26 8 39 20 Moderate EULAR Response (%) 65 46 74 80 Change in DAS28* –1.6 –1.0 –2.1 –1.4 Change in TJC (0-28)* –7.4 –5.1 –8.2 –10.0 Change in SJC (0-28)* –5.2 –2.8 –6.1 –7.8 *Mean change from baseline *Mean change from baselineConclusion: Patients with RA who failed infliximab treatment experienced good outcomes when subsequently treated with adalimumab. Use of adalimumab following infliximab therapy was safe, even in patients who had discontinued infliximab because of intolerance.Citation: Ann Rheum Dis, volume 64, supplement III, year 2005, page 428Session: Rheumatoid Arthritis – Treatment