Background: Vedolizumab (VDZ) is an α4β7 anti-integrin licensed to treat ulcerative colitis (UC) and Crohn's disease (CD). Its gut selectivity may suggest a favourable risk-benefit profile, including a low rate of immunosuppression-related complications. We aimed to assess clinical outcomes and safety of VDZ in IBD patients treated in several hospitals across northern England.
Methods: We retrospectively collected data from electronic records of patients treated with VDZ at 8 UK centres since 2014. Demographic, clinical, and adverse effects data were recorded. We evaluated clinical response at 12 and 52 weeks using the Physician Global Assessment (PGA), Harvey-Bradshaw Index (HBI) or Mayo score. We collected C reactive protein (CRP) and faecal calprotectin (FC) at baseline and follow-up. Fisher exact test and student's t-test were used to determine statistical significance.
Results: Of 183 patients (mean 41 years, F/M ratio 1.4:1) 120 (65.6%) had CD, 61 (33.3%) UC, and 2 (1.1%) IBD-U. 18 patients were active smokers. 57 (31%) received immunomodulators. 68 (37%) received steroid bridging therapy. 27 (15%) patients were anti-TNF naïve. PGA remission was observed in 33 (31%) CD, 26 (44.8%) UC and 2 (100%) IBD-U patients at 12 weeks and in 6/48 (12.5%) CD and 16/36 (44.4%) UC patients at 52 weeks. In addition a partial response was observed in 51 (48%) CD and 25 (43.1%) UC patients at 12 weeks and in 8/48 (16.6%) CD and 10/36 (27.7%) UC patients at 52 weeks.
At 52 weeks, VDZ was more effective in maintaining remission in UC than CD (p<0.05). In CD patients, mean CRP, FC and HBI improved (25.4 vs 15, 862 vs 427, 9.3 vs 6.5; p<0.05 respectively) at 12 weeks, with a further improvement of HBI at 52 weeks (4.45; p<0.05). In UC, mean FC and Mayo score decreased (762 vs 353, 6 vs 3.5; p<0.05) at 12 weeks, whereas CRP did not improve (13.8 vs 11.5; ns). Non-smoking status was associated with better response (p<0.05), regardless of concomitant medications and prior anti-TNF exposure. Forty-three patients (23.5%) discontinued vedolizumab (average exposure 4.5 months).
Reported side effects occurred in 21 cases (11%): 3 urticarial rashes, 6 pneumonias, 3 nasopharyngitis, 2 skin infections, 2 sepsis, 1 viral meningitis, 1 EBV infection, 1 urinary tract infection, and 2 abnormal liver function tests. 1 unrelated death occurred in this cohort. Overall incidence of infection was 12 per 100 person-years of VDZ exposure.
Conclusions: VDZ is a safe and effective therapy even in this cohort of refractory, predominantly anti-TNF exposed patients. Induction data are similar for CD and UC, but VDZ seems to be more successful in maintaining remission for UC compared to CD. The incidence of infectious complications was comparable to that seen with anti-TNF therapies (average 14 per 100 person-years).