Respiratory Tract Infections in Patients With Inflammatory Bowel Disease: Safety Analyses From Vedolizumab Clinical Trials.

Background and Aims: Vedolizumab, a humanised monoclonal antibody for the treatment of inflammatory bowel disease, selectively blocks gut lymphocyte trafficking. This may reduce the risk of respiratory tract infections [RTIs] compared with systemic immunosuppressive therapies. To assess this possibility, we evaluated the rates of RTIs in clinical trials of vedolizumab. Methods: Patient-level data from Phase 3 randomised controlled trials [RCTs] of vedolizumab in ulcerative colitis [UC; GEMINI 1] and Crohn's disease [CD; GEMINI 2], and a long-term safety study [UC and CD] were pooled. Cox proportional hazards models were used to estimate the incidence of upper RTIs [URTIs] and lower RTIs [LRTIs] with adjustment for significant covariates. Results: In the RCTs [n = 1731 patients], the incidence of URTIs was numerically higher in patients receiving vedolizumab compared with those receiving placebo, although this difference was not statistically significant (38.7 vs 33.0 patients per 100 patient-years; hazard ratio [HR] 1.12; 95% confidence interval [CI]: 0.83-1.51; p = 0.463). The rate of LRTIs, including pneumonia, was numerically lower in the vedolizumab versus the placebo group: this difference was not statistically significant (7.7 vs 8.5 per 100 patient-years [HR 0.85; 95% CI: 0.48-1.52; p = 0.585]). Both URTIs and LRTIs were more frequent in patients with CD compared with UC. Most RTIs in patients receiving vedolizumab were not serious and did not require treatment discontinuation. Conclusions: Vedolizumab therapy was not associated with an increased incidence of respiratory tract infection compared with placebo.