Comparative effectiveness and safety of infliximab and adalimumab in patients with ulcerative colitis

Background Real-world comparative benefits and risks of infliximab (IFX) and adalimumab (ADA) in patients with ulcerative colitis (UC) are unclear. Aim To evaluate the comparative effectiveness and safety of IFX and ADA in patients with UC who were new users of anti-TNF agents. Methods Using an administrative claims database (Optum Labs Data Warehouse), we identified patients who received first anti-TNF (IFX, ADA) prescription after a 12-month period without any anti-TNF treatment (baseline), and with a minimum 6-month follow-up after anti-TNF initiation. Primary outcome measures were: all-cause and UC-related hospitalisation, abdominal surgery, corticosteroid use >60 days after starting anti-TNF, and serious infections. We performed 2:1 propensity-score matched Cox proportional hazard analysis, and inverse probability-of-treatment weight (IPTW) analysis, accounting for healthcare utilisation, comorbidities and use of UC-related medication. Results We included 1400 new users of anti-TNF agents (age, 43 ± 15 years; 52% males), from 2006 to 2014. On propensity-score matched analysis, there was no significant difference in the risk of UC-related hospitalisation [IFX vs. ADA; adjusted hazard ratio (aHR), 1.04; 95% confidence interval (CI) 0.71-1.51], corticosteroid use (aHR, 0.85; 95% CI, 0.68-1.06) and serious infections (aHR, 0.62; 95% CI, 0.29-1.34) between IFX- and ADA-treated patients; the number of surgical events was very small. On IPTW analysis, risk of corticosteroid use was significantly lower in IFX - as compared to ADA - treated patients (aHR, 0.82; 95% CI, 0.68-0.99). Results were stable on multiple sensitivity analyses. Conclusions In a large retrospective cohort of patients with UC who were new users of anti-TNF agents, IFX-treated patients may have lower corticosteroid use than ADA-treated patients, but risk of hospitalisation and serious infections were comparable.