Tacrolimus induces short‐term but not long‐term clinical response in inflammatory bowel disease

Summary Background Tacrolimus is a calcineurin inhibitor commonly used for prophylaxis of rejection in renal and liver transplantation. There are limited but favourable data regarding its possible use in patients with inflammatory bowel disease (IBD). Aims To evaluate the efficacy and safety of tacrolimus in patients with IBD in clinical practice. Methods We performed a retrospective, multicentre study in 22 centres in Spain. All adult patients who received oral tacrolimus for luminal or perianal IBD were included. Clinical response was assessed by Harvey‐Bradshaw index and partial Mayo score after 3 months. Perianal disease was evaluated by fistula drainage assessment. Results One hundred and forty‐three patients were included (mean age 38 years; 51% male; median disease duration 110 months). In ulcerative colitis (UC) (n = 58), the partial Mayo score decreased after 3 months from median 6 to 3 (P = 0.0001), whereas in Crohn's disease (CD) (n = 85), the Harvey‐Bradshaw index decreased after 3 months from median 9 to 7 (P = 0.011). In CD patients, blood tacrolimus concentrations during induction (>10 ng/mL vs