Outcomes of tofacitinib dose reduction in patients with ulcerative colitis in stable remission: a long-term follow-up of the randomized RIVETING trial.

Background: Tofacitinib is an oral Janus kinase inhibitor used for the treatment of ulcerative colitis. This study evaluated efficacy/safety of dose reduction to tofacitinib 5 mg twice daily (BID) versus remaining on 10 mg BID in patients in stable remission on 10 mg BID. Methods: RIVETING, a phase 3b/4, double-blind, randomized, parallel-group trial, enrolled patients in stable remission (≥6 months) and corticosteroid-free (≥4 weeks) who received tofacitinib 10 mg BID for ≥2 years. Efficacy was reported to month (M)30 and safety was reported throughout. Results: One hundred and forty patients were randomized (1:1) to tofacitinib 5 or 10 mg BID; 50.0% and 62.9%, respectively, maintained modified Mayo score remission at M30. Remission rate differences at M30 between doses were generally greater in patients with a baseline endoscopic subscore of 1 versus 0, and with versus without tumor necrosis factor inhibitor (TNFi) failure. 11/14 patients who dose-escalated from 5 to 10 mg BID following relapse recaptured remission (median 4.8 months). Serious infection and herpes zoster incidence rates were numerically higher with tofacitinib 10 versus 5 mg BID; overall, adverse event rates were generally similar between doses. Conclusions: Patients on tofacitinib 10 mg BID generally maintained modified Mayo score remission through M30 after reduction to 5 mg BID; most patients who relapsed recaptured remission after dose-escalating back to 10 mg BID. Efficacy was more likely to be maintained following dose reduction in patients with baseline endoscopic subscore 0 versus 1, without versus with prior TNFi failure. Serious infection and herpes zoster incidence was higher with tofacitinib 10 versus 5 mg BID, consistent with known safety profile. ClinicalTrialsgov: NCT03281304.