Use of Vedolizumab in Inflammatory Bowel Disease: A Single-Center Experience.

Background: Vedolizumab, which is a monoclonal antibody that selectively binds to α4β7 integrin in the gastrointestinal system, may be an effective and safe treatment alternative in those with anti-tumor necrosis factor-resistant inflammatory bowel disease.

Methods: Patients administered vedolizumab due to anti-tumor necrosis factor resistant or anti-tumor necrosis factor side effects between August 2017 and November 2020 were included in the study. Crohn's patients were evaluated using the Harvey-Bradshaw index and Simple Endoscopic Score for Crohn's Disease, whereas ulcerative colitis patients were evaluated with the Partial Mayo Score Index and Rachmilewitz score. All patients were followed up for 3 months and their blood samples were taken every 3 months. Hemoglobin, white blood cell, leukocyte, lymphocyte, and platelet counts of the patients were performed. Albumin, C-reactive protein, and erythrocye sedimentation rate values were recorded. The side effect profile for vedolizumab was evaluated for all patients. Among the side effects, arthralgia and flu-like symptoms were observed.

Results: A total of 48 patients (18 ulcerative colitis and 30 Crohn's disease) were included in the study. Vedolizumab therapy was initi- ated in the patients due to anti-tumor necrosis factor resistance (17 ulcerative colitis and 26 Crohn's disease) or anti-tumor necrosis factor side effects (1 ulcerative colitis and 4 Crohn's disease). A total of 30 (63%) patients, including 15 (83%) ulcerative colitis and 15 (50%) Crohn's disease, responded to treatment (both response and remission). The mean duration of response to treatment was 4.5 ± 1.5 months. A total of 20 (42%) patients in the vedolizumab therapy subgroup (10/10, ulcerative colitis/Crohn's disease) went into remission. The mean Harvey-Bradshaw Index value was 9.8 ± 2.8 in the Crohn's disease patients at the time of initial treatment. The mean Simple Endoscopic Score for Crohn's disease value was 11.2 ± 3.1 at the time of initial treatment. The mean Harvey-Bradshaw Index value was 6.5 ± 3.0 and the mean Simple Endoscopic Score for Crohn's disease value was 4.9 ± 3.6 at 6 months post-treatment. The mean Ulcerative Colitis Endoscopic Index (Rachmilewitz) value was 9.3 ± 1.2 at the time of initial treatment. In addition, the mean Partial Mayo Scoring Index was 6.4 ± 1.5 at the time of initial treatment. The mean Ulcerative Colitis Endoscopic Index (Rachmilewitz) value was 0 (0-6.0), and the mean Partial Mayo Scoring Index was 1.5 (0.3-4.0) at 6 months post-treatment.

Conclusion: Vedolizumab therapy is effective in both induction and maintenance of remission in inflammatory bowel disease patients who are resistant to anti-tumor necrosis factor or who can not receive anti-tumor necrosis factor therapy due to side effects. No signifi- cant side effect was observed in the patients during follow-up.