P102 Changes in serum immune protein profiles following vedolizumab therapy in Inflammatory Bowel Disease.

O'Connell, J.(1,2);O'Connell, F.(2);O'Sullivan, J.(2);Kevans, D.(1,2,3);

(1)St James's Hospital, Gastroenterology, Dublin, Ireland;(2)Dublin University- Trinity College, Trinity Translational Medicine Institute, Dublin, Ireland;(3)Dublin University- Trinity College, School of Medicine, Dublin, Ireland;


Vedolizumab(VDZ) is a monoclonal antibody targeting α4β7-integrin which has demonstrated efficacy as induction and maintenance therapy for inflammatory bowel disease(IBD). We aimed to characterise changes in serum immune protein profiles following VDZ induction therapy and evaluate the association between serum immune protein profiles and outcome of VDZ therapy.


IBD patients commencing VDZ induction therapy were prospectively recruited. Patients received VDZ induction as per standard protocol. Week 0 and week 6 pre-infusion serum samples were collected from each patient. Serum samples were analysed using human multiplex panels (Meso Scale Discovery, Rockville, MD, USA ) which quantifies 54 discrete inflammatory proteins. Corticosteroid-free remission(SFR) was assessed at week 14 and 30. Changes in serum immune protein profile were compared between baseline(week 0) and following two VDZ infusions(week 6). Serum immune proteins which demonstrated a significant week 0 to 6 change were evaluated as candidate biomarkers of week 14 and 30 SFR. Continuous variable are presented as median[range]. P values < 0.05 were considered significant.  


N=39 IBD patients were included: age 50.4[18.2-75.8] years, UC phenotype 51%, male 51%; disease duration 13.4[0.4 – 40.8] years, clinical Mayo subscore 4[0 – 9] and HBI 7[1 – 20]. 7 of 54 analytes demonstrated a significant change from baseline to week 6. Eotaxin(p=0.001), Eotaxin-3(p=0.001), TNF-b (p<0.008), TARC(p=0.015), bFGF( p=0.034) and MIP1-b(p=0.043) increased from baseline to week 6. IL-15(p<0.001) reduced from baseline to week 6. There was no association between any of these 7 immune proteins and VDZ therapy outcome at week 14 or 30.


Changes in serum immune protein concentrations with pro-inflammatory, immunoregulatory and chemotactic functions are observed following VDZ induction therapy. Further study is required to identify serum biomarkers of VDZ therapy response.