23 EFFECTS OF VEDOLIZUMAB ON EXTRAINTESTINAL MANIFESTATIONS IN INFLAMMATORY BOWEL DISEASE

Abstract Background Vedolizumab (VDZ) is an α4β7 integrin monoclonal antibody that is effective for both Crohn’s disease (CD) and ulcerative colitis (UC). There is limited data on how vedolizumab’s gut selective mechanism impacts extraintestinal manifestations (EIM) in inflammatory bowel disease (IBD). Methods A retrospective study of all IBD patients at our institution who received at least 1 dose of VDZ between 1/1/2014 and 8/1/2019 were included. Primary outcome was rate of new or worsening EIMs after initiation of VDZ. Secondary outcomes were factors associated with new or worsening EIMs after VDZ. Continuous variables were analyzed using an unpaired student’s t-test. Categorical variables were analyzed using a chi-square test or Fisher’s exact test. A multivariable logistic regression model was built to identify factors associated with EIMs. The final model was obtained by sequentially subtracting variables and retaining variables that were independently associated with EIMs while controlling for other factors. We also identified factors associated with new or worsening of EIMs after VDZ therapy using Fisher’s exact testing and univariable logistic regression. Results A total of 142 patients were included (53.5% with CD, 41.6% with UC, and 4.9% with indeterminate colitis). The median age was 39 years (range 15–78), and 49.3% were women (Table 1). EIMs were noted in 53.5% (n=76) and included: peripheral arthritis (39.4%), sacroileitis (15.5%), erythema nodosum/pyoderma gangrenosum (9.2%), uveitis (4.9%), and episcleritis (0.7%). Twenty patients had more than one EIM. Significant factors associated with having EIMs included female sex (63.2% with EIM vs 33.3% without, p-value < 0.01), tobacco use (23.7% with EIM vs 6.1% without, p < 0.01), CD (60.5% with EIM vs 45.5% without, p=0.02), and prior biologic agent use (94.7% with EIM vs 74.2% without, p < 0.01). On multivariable analysis, female sex (OR 3.19, 95% CI 1.52–6.72), tobacco use (OR 4.84, 95% CI 1.45–16.23), and prior biologic agent use (OR 4.30, 95% CI 1.30–14.20) were the only significant factors. Of the 76 patients with EIMs, 71.1% (n=54) had stable or improved EIMs after starting VDZ and 28.9% (n=22) had worsening or new EIMs after VDZ. Patients who were on steroids at the time of VDZ induction were more likely to have stable or improved EIMs compared to who did not receive concomitant steroid therapy (OR for worsened EIMs 0.20, 95% CI 0.06–0.63) (Table 2). Prior biologic use and current combination therapy did not significantly predict worsening or new EIMs. Conclusion Female sex, tobacco use, and prior biologic agent use are significantly associated with EIMs of IBD. Post-VDZ, the majority of patients had stable to improved EIMs. Patients on concomitant steroid therapy at the time of VDZ induction were more likely to have improved or stable EIMs compared to patients not on steroids.