OP29 Peripheral blood DNA methylation biomarkers accurately predict clinical- and endoscopic response to vedolizumab in a real-life cohort of Crohn’s Disease patients

Abstract

Background: Despite the proven efficacy of vedolizumab (VDZ), only 29% and 36% of the Crohn's disease (CD) patients present corticos-teroid-free clinical-and endoscopic remission, respectively. Therefore, predictive biomarkers for treatment success would be of extreme value. Previous studies have identified aberrant DNA methylation associated with CD-specific phenotypes, suggesting that the methylome may be useful for classification and prediction of VDZ treatment response. Here, we sought to identify such DNA methylation biomarkers that can predict clinical-and endoscopic response to VDZ in CD patients. Methods: We prospectively recruited adult CD patients that initiated VDZ treatment following a baseline colonoscopy in two cohorts: a discovery and validation cohort. Peripheral blood DNA methylation profiles were measured prior to treatment (T1), and after a median of 22 weeks (T2) using the Illumina Infinium HumanMethylation EPIC