Comparative risk of serious infection with vedolizumab vs anti-TNF in inflammatory bowel disease: results from nationwide Swedish registers

Objectives: We aimed to assess the risk of serious infection in inflammatory bowel disease (IBD) patients treated with vedolizumab, compared to those treated with anti-tumor necrosis factors (TNF) and the general population. Methods: In this Swedish cohort study, treatment episodes were identified from nationwide health registers. We used Cox regression with propensity score-matched cohorts to estimate hazard ratios (HRs) for incident serious infections, defined as infections requiring hospital admission. Results: During 1376 treatment-episodes in Crohn’s disease, the rate of serious infections per 100 person-years (PY) was 5.18 (95%CI=3.98-6.63) with vedolizumab vs 3.54 (95%CI=2.50-4.85) with anti-TNF; HR=1.72 (95%CI=1.12-2.65), partly explained by more gastrointestinal infections. Compared to the rate of 0.75/100 PYs (95%CI=0.59-0.92) in a matched general population cohort, vedolizumab demonstrated higher risk (HR=7.00; 95%CI=5.04-9.72). During 1294 treatment-episodes in ulcerative colitis, the corresponding rates were 3.74/100 PYs (95%CI=2.66-5.11) with vedolizumab vs 3.42/100 PYs (95%CI=2.31-4.89) with anti-TNF; HR=0.80 (95%CI=0.47-1.36) during the initial 1.1 years and HR=2.03 (95%CI=0.65-6.32) after 1.1 years (truncated due to non-proportional hazards). Pneumonia accounted for 40% of all infections among anti-TNF whereas no case was observed among vedolizumab episodes. Compared to the rate of 0.69/100 PYs (95%CI=0.53-0.87) in a matched general population cohort, vedolizumab showed an HR of 5.45 (95%CI=3.67-8.11). Conclusions: Vedolizumab was associated with increased risks of serious infections compared to anti-TNF in Crohn’s disease, but not in ulcerative colitis. Nonetheless, the panorama of serious infections seemed to differ between the drugs. Our findings underscore the importance of clinical awareness of infections and the safety profile of the two therapies.