W1243 Concomitant Use of Immunosuppressive Therapy in An Outpatient IBD Subspecialty Clinic Results in Rates of Response Higher Than Those Seen in the Infliximab Randomized Controlled Trials

Abstract

(Background: for bold) Infliximab has confirmed efficacy from RCTs for the induction and maintenance of remission of active luminal and fistulizing Crohn's disease (CD). What have been less clearly described are the long-term outcomes of maintenance infliximab therapy outside of the rigors of a clinical trial setting and in actual clinical practice. (Aims: for bold) The objective of this cohort study was to examine, in an outpatient IBD specialty clinic, the induction and maintenance responses to infliximab in patients with moderately severe active CD. (Methods: for bold) A retrospective chart review was conducted of all Crohn's disease patients treated at a large, urban university hospital that serves as a quaternary IBD referral center. All patients treated with induction and maintenance dosing of infliximab were identified and their records reviewed for patient demographics, and clinical responses. Clinical response was defined by physician global assessment and off corticosteroids. (Results: for bold) 151 patients were identified of whom 133 had sufficient records to be entered into the analysis. The study population was 53% female; 98% Caucasian; mean age at initiation of therapy was 36.5 yrs; mean duration of disease from diagnosis to infliximab treatment was 11.5 yrs. Anatomic distribution of CD was 36% ileal, 32% colonic and 32% ileo-colonic. 117/133 (89%) of patients had a clinical response to induction and continued with maintenance infliximab therapy. 105/117 (90%) patients were on concomitant immunomodulatory therapy: azathioprine/6-MP 81/105 (69%); methotrexate 24/105 (21%). The mean duration of clinical response was 94.0 wks (95% CI 78.8-109.2). The proportion of patients with an ongoing clinical response at week 30 was 83.2%, at week 54 was 63.6% and at week 104 was 44.9%. In all, 36 (30.8%) patients lost response (LR) defined as worsening of symptoms, initiation of new CD therapy, or need for surgery. The mean time to LR was 63.8 weeks (95% CI 49.4-78.2). 15/117 (12.8%) patients experienced an adverse event (AE), resulting in the discontinuation of infliximab in 7 (6.0%) patients. AE's included 9 infusion reactions, 4 serum sickness-like reactions, 1 rash of unknown significance and 1 serious infection (osteomyelitis of the jaw). There were no cases of malignancy or death. (Conclusions: for bold) Patients starting infliximab in an IBD outpatient specialty clinic were demographically similar to those in the RCTs. Nevertheless, a higher number were using concomitant immunosuppressive therapy and demonstrated higher induction and maintenance of response rates.