Efficacy of Vedolizumab in Crohn's Disease Patients Naive to Biological Therapy

INTRODUCTION: Vedolizumab is a gut selective anti-integrin agent which binds to the alfa4beta7 integrin, preventing its coupling to the endothelial MadCAM-1. It reduces leucocyte trafficking from the endothelium consequently reducing intestinal tissue inflammation. There is scarce evidence on the use of vedolizumab in CD in Brazil, mostly in patients with no previous biological therapy, where the drug seems to have a more adequate therapeutic potential. Tha primary aim of the study is to analyze clinical remission rates at weeks 12, 26 and 52, and at last follow-up on naive CD patients submitted to vedolizumab therapy. Secondary outcomes will be clinical response rates at weeks 12, 26 and 52, and at last follow-up; endoscopic remission rates in colonoscopies performed; persistence of drug therapy over time; adverse events during treatment with vedolizumab and rates of abdominal surgery during therapy. METHODS: A retrospective, longitudinal, observational study will be performed with patients with CD who used Vedolizumab at any time of their treatment as the first biologic option, after failure of conventional therapy. Following the induction dose of 300 mg at weeks 0, 2 and 6, and maintenance of 300 mg every 8 weeks, patients will be followed up to 52 weeks (1 year) or more (last follow-up captured). Records of the clinical evaluations at week 12, 26 and 52, and last follow-up, will be checked according to the HBI and PGA to define clinical response or clinical remission. Colonoscopies will also be checked to evaluate mucosal healing. Electronic charts will be reviewed also to analyze adverse events and surgery during therapy.