Safety of Consecutive Vedolizumab and Iron Infusions: A Retrospective Cohort Study

Abstract

Introduction: Vedolizumab, a novel biologic targeting alpha 4-beta 7 integrin, is approved for the treatment of moderate to severe inflammatory bowel disease (IBD). Side effects of vedolizumab include acute and delayed infusion reactions. Many patients with IBD have concurrent iron deficiency anemia and require intravenous (IV) iron. While some practices administer IV iron immediately after the vedolizumab, others require patients to receive the iron at a separate visit. For those who work or live far from the clinic, this can be quite challenging. The goal of this study was to evaluate whether consecutive infusions of IV iron and vedolizumab are associated with an increased number of infusion reactions. Methods: A single center retrospective chart review for all patients with IBD treated with vedolizumab from 1/2014 to 6/2018 was conducted. Basic demographic data was collected (Table 1). All delayed (≥ 24 hours after the infusion) infusion reactions were documented. Administration of IV iron at the same clinic visit was recorded, including the type of iron and the dose. Chi-squared and Fisher's tests were used to compare categorical variables and Student t tests were used to compare continuous variables. Results: 2,627 vedolizumab infusions (335 patients) were identified and included for analysis. The average age was 41.5 years, 175 (52%) were male and 217 (65%) had a diagnosis of ulcerative colitis. 489 (18.6%) vedolizumab infusions were immediately followed by an IV iron infusion. The majority (94%) of these patients were given iron sucrose (200 mg) and 6% received ferric carboxymaltose (750 mg). No acute iron infusion reactions occured. 19 delayed vedolizumab infusion reactions were identified; of these, 5 (26%) occurred in patients who also received IV iron at that visit (immediately following the vedolizumab). There was no significant difference in the number of delayed infusion reactions between those who received IV iron at the same visit and those who did not (p=0.3753). Conclusion: Vedolizumab is effective in treating patients with moderate to severe IBD and delayed infusion reactions are rare. Infusion of IV iron immediately following a vedolizumab infusion is often more convenient for patients and was not associated with more delayed infusion reactions in this study. Therefore, for patients who cannot easily return to the clinic, such as those who work or those who live far from the office, consecutive infusion of vedolizumab and iron at the same visit is a viable option.601 Figure 1. Patient Characteristics