P733 Serum interleukin-6 level predicts future outcomes of infliximab for ulcerative colitis. (16th January 2018) - Nishida, Y
Abstract: Background: Infliximab (IFX) is effective in patients with ulcerative colitis (UC); however, one-third of patients do not respond to IFX and need further therapies such as other biologic agents. Recently the association of pre-treatment serum interleukin (IL)-6 and clinical response to IFX has been reported in several disease; however, it has not been sufficiently evaluated in UC. Furthermore, soluble mucosal vascular addressin cell adhesion molecule-1 (sMAdCAM-1), targeted by newly developed biologics: natalizumab or vedolizumab, might be useful in monitoring and managing the progression of variety of major chronic inflammatory diseases, however no studies have reported the clinical utility of serum sMAdCAM-1 levels in UC. Therefore, the aim of this study was to examine levels of pro-inflammatory molecules in UC patients receiving IFX to identify possible markers predictive of its efficacy, which may aid in treatment selection. Methods: Patients with moderate-to-severe active UC receiving IFX in our hospital between 2010 and 2016 and whose pre-treatment serum samples were available were retrospectively evaluated. We analysed the association between serum IL-6, tumour necrosis factor-α (TNF-α), and sMAdCAM-1 and the clinical efficacy of IFX. The primary endpoint was clinical response at the end of the induction period. Clinical response was defined as a partial Mayo score reduction ≥ 3 points accompanied by a decrease in the rectal bleeding subscore ≥ 1 or an absolute rectal bleeding subscore of 0 or 1 without death due to UC attach, proctocolectomy nor secondary alternative drug use such as tacrolimus or corticosteroid. Results: Forty-one patients were included in this study. After induction therapy, 27 patients (65.9%) showed a clinical response. According to the results of a univariate analysis, IL-6 levels were significantly lower in responders ( p = 0.012), whereas no significant differences were noted in other factors including sMAdCAM-1 and TNF-α. Multivariate analysis identified IL-6 levels (Odds ratio = 1.39, 95% confidence interval: 1.04–1.85, p = 0.027) as an independent prognostic factor associated with clinical response. Cut-off values of IL-6 (5.66 pg/ml) enabled discrimination of responders from non-responders. Conclusions: Pre-treatment serum IL-6 level predicts the efficacy of IFX in patients with UC. Measuring IL-6 would help clinicians choose the right treatment option.