P724 Vedolizumab use is not associated with increased malignancy incidence: GEMINI LTS study results and post-marketing data

Abstract

Background Vedolizumab is a gut-selective antibody to α4 β7 integrin approved to treat moderate-to-severe Crohn's disease and ulcerative colitis in adults. Inflammatory bowel disease (IBD) and immunosuppressant use are associated with increased risk of malignancy. Aim To analyse the incidence of malignancy with vedolizumab treatment in the GEMINI long-term safety (LTS) study and post-marketing (PM) setting. Methods Malignancy data from the LTS study (May 2009 to May 2018), and data from the vedolizumab Global Safety Database (20 May 2014 to 19 May 2018), were identified using Medical Dictionary for Regulatory Activities coding. The number of patients experiencing malignancies in the LTS study (excluding malignancies within 1 year following vedolizumab initiation) was indirectly standardised against the number expected, using age- and sex-specific rates in patients with IBD from Optum's Clinformatics™ Data Mart (CDM) database. Results Among 1785 patients with ≥1 year of follow-up post-vedolizumab initiation in the LTS study (total 5670 patient-years), observed numbers of malignancies were similar to those expected compared with CDM data (31 vs 29; ratio of observed to expected events = 1.08; P = 0.71; 95% confidence intervals [CI] 0.73, 1.53). The most common malignancies were renal and bladder (6). PM, 293 patients reported 299 malignancies (including malignancies within 1 year following vedolizumab initiation), in approximately 208 050 patient-years of vedolizumab exposure. Lower gastrointestinal malignancies were most common (59). Conclusions The number of malignancies in the LTS study was similar to that expected from an IBD population with no statistically significant differences, although few confounders could be corrected for. Limitations of PM safety reporting require consideration; however, the number of malignancies with vedolizumab appeared low.