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P509 Biomarkers of neutrophil activity and extracellular matrix turnover predict long-term response to vedolizumab in patients with Crohn’s disease


 
 
 Crohn‘s disease (CD) is a form of inflammatory bowel disease characterized by high infiltration of immune cells into the intestinal tissue, resulting in increased proteolytic mediated extracellular matrix (ECM) remodeling. Disease management has improved with the use of biologics such as vedolizumab (VEDO). However, considering the high rate of primary non-response to VEDO, there is an unmet need for predictive serum biomarkers capable of determining response to treatment prior to its initiation. This study investigated whether biomarkers of neutrophil activity, mucosal damage, and ECM remodeling could serve as non-invasive tools for predicting long-term response to VEDO in patients with CD.
 
 
 
 Serum biomarkers of human neutrophil elastase (HNE)-derived fragment of calprotectin (CPa9-HNE [serum calprotectin]) and matrix metalloproteinase (MMP)-derived fragments of type I (C1M), III (C3M), IV (C4M), type III collagen formation (PRO-C3), basement membrane turnover (PRO-C4) and T-cell activity (C4G), were measured using protein fingerprint assays in patients with CD (n=32) before VEDO therapy initiation. The ratio C4M/C4G (myeloid/lymphoid mediated degradation) was computed. Long-term response was defined as the continuation of treatment beyond one year after the start of therapy. Baseline biomarker levels were compared between responders and non-responders using Mann-Whitney U-tests, and area under the curve (AUC) values were generated using receiver operating characteristics (ROC) statistics. Biomarker levels were divided into tertiles and chi-square tests were used to investigate the relationship between tertiles and response proportions.
 
 
 
 Biomarkers CPa9-HNE, C1M, C3M, C4M, PRO-C3, C3M/PRO-C3, and C4M/C4G were significantly increased at baseline in non-responders compared with responders (all P<0.05). All markers were able to predict response to VEDO at baseline (AUC [95% CI]: CPa9-HNE 0.81 [0.66–0.96]; C1M 0.85 [0.75–0.98]; C3M 0.79 [0.62–0.95]; C4M 0.77 [0.6–0.93]; C3M/PRO-C3 0.78 [0.6–0.95]; C4M/C4G 0.74 [0.56–0.92] all P<0.05). Proportions of long-term VEDO users were highest in the first tertiles for all the markers (73–91%) and decreased in a concentration-dependent manner across the second and third tertiles, indicating that patients with the lowest concentrations of these markers less frequently discontinued treatment at one year after initiation (Figure 1).
 
 
 
 
 Baseline levels of serum biomarkers for neutrophil activity (CPa9-HNE [serum calprotectin]) and mucosal damage (C1M, C3M, C4M, C4G, PRO-C4, and PRO-C3) could predict long-term response to VEDO in patients with CD. Therefore, these biomarkers could aid in early decision making concerning treatment with vedolizumab in patients with CD.
