IL-17 Inhibitors and Inflammatory Bowel Diseases: A Postmarketing Study in Vigibase

Several gastrointestinal symptoms and chronic inflammatory bowel diseases (IBDs) have been reported after therapy with IL-17 inhibitors. To date, however, no study has shown a clear association between these drugs and IBD onset. We searched on Vigibase, the worldwide pharmacovigilance database, to investigate reporting prevalence, characteristics, and prognosis of all gastroenterological adverse events in patients treated with IL-17 inhibitors. In total, 1,129 gastrointestinal Individual Case Safety Reports (ICSRs) were identified, including 850 IBD (42.5% Crohn's disease, 31.9% ulcerative colitis, and 25.6% undifferentiated IBD) and 279 colitis (mainly undifferentiated colitis (79.2%), and microscopic colitis (10.4%)). ICSRs were associated with secukinumab (SEC, 83.6%) or ixekizumab (IXE, 16.3%), whereas only one colitis occurred with brodalumab (0.1%). Most IBD and colitis cases were detected within 6 months from therapy start in both the SEC (68.8% and 73.5%) and IXE groups (100% and 66.7%). Patients' outcomes were reported in 428 ICSRs (37.9%). Complete or ongoing recovery from symptoms was detected in about two-thirds of patients experiencing IBD (59.5%) or colitis (64.2%), whereas in the other cases, there was no recovery (33.9% and 29.5%) or there were sequelae (5.4% and 4.2%). Fatal events occurred in four patients (1.2%) in the IBD group (3 after SEC and on1e with IXE) and two SEC-treated subjects in the colitis group (2.1%). Treatment with IL-17 inhibitors is associated with a relevant number of exacerbations and new onset of IBD and colitis. Careful evaluation of gastrointestinal symptoms and the monitoring of intestinal inflammatory biomarkers should be recommended before prescribing these drugs.