P555 Switching from intravenous vedolizumab to subcutaneous maintains clinical remission even in intensified patients with Inflammatory Bowel Disease. One year follow-up

Abstract

Abstract Background Vedolizumab is a humanized monoclonal antibody. It is indicated for moderate to severe flare of Inflammatory Bowel Disease (IBD). Subcutaneous (SC) vedolizumab, is a major advantage for patients for home administration. This study aimed to analyze the percentage of clinical and biochemical remission at 52 weeks in all IBD patients on treatment with intravenous (IV) vedolizumab after switching to the SC one. Methods Single-center, descriptive, observational, and retrospective study. The study included all the IBD patients (19 patients) who were at the moment of inclusion with IV vedolizumab treatment in a tertiary hospital, who underwent a switch from IV vedolizumab to SC vedolizumab. In addition, the relationship between treatment with intensified IV vedolizumab and subsequent drug levels versus patients without intensification for 52 weeks. Results Ten patients (22.6%) were diagnosed with Ulcerative Colitis (UC) and 9 patients (47.3%) with Crohn´s disease (CD). The baseline characteristics of the 19 patients are described in Table 1. Reasons for starting IV vedolizumab: there was loss of response to a first anti-TNF in 10 patients (52.6%) and loss of response to two previous anti-TNFs was observed in 3 patients (15.7%). In 4 patients (21%) IV vedolizumab was started as the first line of treatment due to the increased risk of infections and a previous history of neoplasia. Finally, in 2 patients with CD (10.5%) it was started as prevention of recurrence. Up to a total of 8 patients (42.1%) were on an intensified IV vedolizumab before switching to SC vedolizumab. All 19 patients (100%) were in clinical remission and 15 patients (78.9 %) remained in biochemical remission prior to switching to SC vedolizumab. At the end of the follow-up (52 weeks) all of them achieved clinical remission and 17 patients (89.4%) achieved biochemical remission (Figure 1). Therefore, biochemical remission was achieved in 10% more patients after the switch. It was noted that biochemical remission was achieved in 87% of patients on the intensified regimen with IV vedolizumab versus 100% of patients on the non-intensified regimen. No statistically significant differences were obtained between patients who had been on intensified IV vedolizumab and those who had not. At one year of follow-up, SC vedolizumab was suspended in one patient due to muscle pain, and IV vedolizumab was restarted again. Conclusion Following the standard dose switch of SC vedolizumab, clinical remission is maintained, achieving biochemical remission in 89.4 % of patients one year with SC vedolizumab with maintained vedolizumab levels, even in previously intensified IV vedolizumab patients.