Purpose: Two double-blind, placebo-controlled trials (ULTRA 1 and 2) revealed adalimumab (ADA) therapy significantly reduces hospitalization and non-significantly decreases colectomy rates in patients with moderate to severe ulcerative colitis (UC).1 We assessed the effect of an ADA 160/80/40 mg treatment regimen on risk reduction of all-cause and UC-related hospitalization and colectomy in these 2 trials among initial ADA-responders. Methods: The pooled dataset included 939 patients (471 ADA, 468 placebo [PBO]). Hospitalization and colectomy events were based on safety reports reviewed by 2 gastroenterologists who were blinded to treatment. Conservatively, hospitalizations from initial ADA non-responders (per Mayo score at Week 8) through Week 8 were counted, but were censored after Week 8 to reflect the clinical practice pattern of continuing treatment in initial ADA-responders. Risk and number of hospitalizations were compared between groups using person-year (PY)-based incidence rates (IRs) and Poisson regression, respectively; z-scores were used to assess statistical differences.2 Results: 35% and 36% reductions in the number of patients hospitalized and number of hospitalizations for any reason, respectively, were observed with ADA therapy vs. PBO (Table, P<.05 for both comparisons). When UC-related hospitalizations were compared, reductions for rate (55%) and number (56%) of hospitalizations were both statistically significant, too.Table: Hospitalization and colectomy IRs in ULTRA 1 and ULTRA 2 trials: week-8 ADA respondersConclusion: Initial ADA-responders had a significantly lower risk for UC-related and all-cause hospitalization compared with PBO. Reduction of all-cause hospitalization is unique for ADA compared to any other anti-tumor necrosis factor agent. A non-significantly lower colectomy rate in patients receiving ADA vs. PBO also was observed.