Objective: Tacrolimus (TAC) is an important therapeutic option for remission induction in patients with refractory ulcerative colitis (UC). However, there is little evidence available on long-term outcomes and maintenance treatments after TAC therapy, especially in cases with previous tumor necrosis factor-α (TNF-α) inhibitor therapy.

Methods: Long-term outcomes and remission induction after TAC treatment were retrospectively examined in refractory UC patients with and without previous TNF-α inhibitor therapy.

Results: The mean disease activity index and the endoscopic activity index scores decreased significantly during the 12-week treatment after TAC therapy in both groups, showing a significantly greater decrease in the group without TNF-α inhibitor therapy than in the group with previous TNF-α inhibitor therapy. One year or more after TAC therapy, TNF-α inhibitor and/or azathioprine was used as maintenance therapy in most cases in the group without previous TNF-α inhibitor treatment, while azathioprine was primarily used in the group with previous TNF-α inhibitor treatment. Colectomy was performed in 45.5% (5/11) and 15.6% (7/45) of the groups with and without previous TNF-α inhibitor therapy, respectively, and the group without previous TNF-α inhibitor treatment had a better colectomy-free rate than the group with previous TNF-α inhibitor treatment after TAC therapy on Kaplan-Meier analysis.

Conclusions: TAC is effective for remission induction in refractory UC patients with and without previous TNF-α inhibitor treatment. Maintenance medication after TAC therapy is an issue for the future, especially in UC cases with previous TNF-α inhibitor treatment failure.