Anti-TNF withdrawal or long-term treatment in ulcerative colitis (BIOSTOP): a multicentre open label, randomized controlled trial.

Anti-tumour necrosis factor (anti-TNF) treatment is effective in ulcerative colitis (UC). Optimal treatment duration is uncertain. This trial studies outcome after anti-TNF withdrawal compared to maintenance treatment in UC. In this prospective, multicentre, randomized, controlled, open-label non-inferiority study, patients in deep clinical, biochemical and endoscopic remission were randomized 1:1 to anti-TNF withdrawal or maintenance treatment. Primary endpoint was endoscopically confirmed remission (Mayo Endoscopic Score 0 or 1) after two years, including UC flares treated with anti-TNF, or non-biologic agents. Secondary endpoints were clinical remission, UC flare rate and treatment response. We needed 170 participants to show non-inferiority with a 15% margin. Between June 2017 and December 2021, 172 UC patients from 19 Norwegian hospitals were randomized; 86 in each group. The per-protocol population was 163 patients. Nine patients were excluded due to consent withdrawal or protocol violation. Eighty percent (66/82) of anti-TNF withdrawal and 96% (78/81) of maintenance patients were in endoscopic remission after 2 years. UC flares occurred in 52% (45/86) of withdrawal and 12% (10/86) of maintenance patients. Anti-TNF retreatment was successful in 74% (20/27). Two years after anti-TNF withdrawal in UC patients in deep remission, endoscopically confirmed remission rate was significantly lower compared to maintenance treatment. Non-inferiority could not be proven. UC flare rate after anti-TNF withdrawal was high, but most were successfully treated. The majority did not receive AZA. Importantly, 48% of anti-TNF withdrawal patients remained in steroid-free remission. No significant predictors for UC activity after anti-TNF withdrawal were identified. ClinicalTrials.gov (registration number NCT03011268), and EudraCT (registration number 2016-001409-18).