Tacrolimus for ulcerative colitis in children: a multicenter survey in Japan.

Background/aims: Tacrolimus is effective for refractory ulcerative colitis in adults, while data for children is sparse. We aimed to evaluate the effectiveness and safety of tacrolimus for induction and maintenance therapy in Japanese children with ulcerative colitis.

Methods: We retrospectively reviewed the multicenter survey data of 67 patients with ulcerative colitis aged < 17 years treated with tacrolimus between 2000 and 2012. Patients' characteristics, disease activity, Pediatric Ulcerative Colitis Activity Index (PUCAI) score, initial oral tacrolimus dose, short-term (2-week) and long-term (1-year) outcomes, steroid-sparing effects, and adverse events were evaluated. Clinical remission was defined as a PUCAI score < 10; treatment response was defined as a PUCAI score reduction of ≥ 20 points compared with baseline.

Results: Patients included 35 boys and 32 girls (median [interquartile range] at admission: 13 [11-15] years). Thirty-nine patients were steroid-dependent and 26 were steroidrefractory; 20 had severe colitis and 43 had moderate colitis. The initial tacrolimus dose was 0.09 mg/kg/day (range, 0.05-0.12 mg/kg/day). The short-term clinical remission rate was 47.8%, and the clinical response rate was 37.3%. The mean prednisolone dose was reduced from 19.2 mg/day at tacrolimus initiation to 5.7 mg/day at week 8 (P< 0.001). The adverse event rate was 53.7%; 6 patients required discontinuation of tacrolimus therapy.

Conclusions: Tacrolimus was a safe and effective second-line induction therapy for steroid-dependent and steroid-refractory ulcerative colitis in Japanese children.