ABSTRACT
INTRODUCTION: Ustekinumab use in ulcerative colitis had shown low adverse event and high persistence rates to 3 years via the UNIFI long-term extension study. Outcomes beyond 3 years have not been previously described. We describe the safety signals of the entire UNIFI Australian population beyond 3 years. METHODS: This retrospective multicenter observational cohort study recruited from all Australian UNIFI centers. The primary outcome was safety via adverse events. Secondary outcomes included the clinical relapse rate on ustekinumab, and the need to switch from ustekinumab to an alternate agent. RESULTS: There were 14 patients [11 male, mean age 47 (±14) years], with a median diagnosis of 10.8 (±4.5) years prior to UNIFI enrollment. Median follow-up was 298 weeks (5.7 years) (Interquartile range (IQR): 220-311 weeks). Within the long-term extension, there were three serious adverse events and one minor event. 42.9% (6/14) patients had clinical relapses, of which clinical remission was recaptured in 83.3% (5/6). 85.7% (12/14) persisted on ustekinumab in the long-term, with 7.1% (1/14) electively ceasing ustekinumab and 7.1% (1/14) changed from ustekinumab due to clinical relapse. CONCLUSION: For moderate-to-severe UC in Australia, ustekinumab maintained efficacy beyond 3 years with a high persistence rate and no new safety signals. TRIAL REGISTRATION: The trial is registered at ANZCTR (identifier: ACTRN12622001332718).
