RT Journal Article SR Electronic T1 Association of trough vedolizumab levels with clinical, biological and endoscopic outcomes during maintenance therapy in inflammatory bowel disease JF Frontline Gastroenterology JO Frontline Gastroenterol FD BMJ Publishing Group Ltd SP 117 OP 123 DO 10.1136/flgastro-2019-101197 VO 11 IS 2 A1 Nikolas Plevris A1 Philip W Jenkinson A1 Cher S Chuah A1 Mathew Lyons A1 Lynne M Merchant A1 Rebecca J Pattenden A1 Ian D Arnott A1 Gareth R Jones A1 Charlie W Lees YR 2020 UL http://fg.bmj.com/content/11/2/117.abstract AB Objective To establish the relationship between trough vedolizumab levels and outcomes during maintenance therapy.Design Cross-sectional service evaluation was performed on patients with inflammatory bowel disease (IBD) receiving maintenance vedolizumab therapy (minimum of 12 weeks following induction). Prior to infusion, data on clinical activity (Harvey-Bradshaw Index or partial Mayo score), trough C-reactive protein (CRP)/vedolizumab levels and faecal calprotectin were collected. Endoscopic data (±8 weeks from vedolizumab level testing) were obtained by review of medical records. Vedolizumab levels were processed using the Immundiagnostik monitor ELISA.Setting The Edinburgh IBD Unit, Western General Hospital (tertiary IBD referral centre).Patients Seventy-three patients (30 ulcerative colitis and 43 Crohn’s disease) were identified who fulfilled inclusion criteria and had vedolizumab levels matched with clinical activity scores, CRP and faecal calprotectin. Of these, 40 patients also had matched endoscopic data.Main outcome measures The association of trough vedolizumab levels with clinical remission (Harvey-Bradshaw Index <5 or partial Mayo <2), biologic remission (faecal calprotectin <250 µg/g+CRP <5 mg/L) and endoscopic remission (Mayo score 0/no inflammation and ulceration on colonoscopy).Results The median trough vedolizumab levels were similar between patients in and not in clinical remission (10.6 vs 9.9 µg/mL, p=0.54); biologic remission (10.6 vs 9.8 µg/mL, p=0.35) and endoscopic remission (8.1 vs 10.2 µg/mL, p=0.21). Quartile analysis revealed no significant increase in the proportion of patients in clinical remission, biologic remission or endoscopic remission with increasing trough vedolizumab levels (p<0.05).Conclusions In this cohort, trough vedolizumab levels were not associated with clinical, biological or endoscopic outcomes during maintenance therapy.