P753 Comparing long-term outcomes in inflammatory bowel disease patients between switch and non-switch cohorts: no differences in infliximab persistence or safety outcomes after 54 months

Suo, P.(1)*;Thin, L.(2);Srinivasan, A.(3);Winston, J.(4);Jeffrey, A.(5);Menon, S.(5);Ghaly, S.(6);Haifer, C.(7);

(1)St Vincent's Hospital, Department of Gastroenterology, Sydney, Australia;(2)Fiona Stanley Hospital- University of Western Australia, Department of Gastroenterology, Perth, Australia;(3)Eastern Health- University of Melbourne, Department of Gastroenterology, Melbourne, Australia;(4)Eastern Health, Department of Gastroenterology, Melbourne, Australia;(5)Royal Perth Hospital, Department of Gastroenterology, Perth, Australia;(6)St Vincent's Hospital- St Vincent’s Clinical School- UNSW Sydney, Department of Gastroenterology, Sydney, Australia;(7)St Vincent's Hospital- St Vincent's Private Hospital, Department of Gastroenterology, Sydney, Australia;


Switching patients with inflammatory bowel disease (IBD) from originator to biosimilar infliximab has been demonstrated to be non-inferior to continuing originator infliximab by several studies. However, data comparing treatment outcomes beyond 12-months across switch and non-switch cohorts specific to IBD patients remains comparatively underreported. Here we report long-term (>48 weeks) treatment outcomes of the  SAME study, a large-scale parallel cohort study of Australian IBD patients who underwent non-medical switching from originator to biosimilar (CT-P13) (n=204) or continued originator infliximab (n=141).


The SAME study was a multi-centre, prospective parallel cohort non-inferiority study across seven Australian hospitals over 48 weeks undertaken between May 2017 to October 2019. The data that we present here is the long-term extension study, obtained retrospectively, which sought to compare long-term infliximab persistence beyond 48 weeks across switch and non-switch cohorts. This study included five of the original seven sites, three of which switched from originator to biosimilar infliximab. The primary outcome was infliximab persistence, defined as the proportion  of originator or biosimilar infliximab treated patients from the original cohort at last follow up. Secondary outcomes included disease worsening requiring infliximab dose escalation or discontinuation, rates of adverse events, and development of antibodies to infliximab (>10ng/mL). 


Data from 263 (90 Ulcerative colitis and 173 Crohn’s disease) of 345 (76%) patients enrolled in the original SAME study were included with median follow up of 54.2 months (IQR 46.1-59.3). At last follow-up, 103 (65.5%) and 68 (64.2%) patients across the switch and non-switch cohorts (p = 0.8) remained on infliximab. There were no differences in the proportions that discontinued infliximab due to clinical or biochemical worsening of disease (21.7 v 23.6%, p = 0.72); required infliximab dose escalation (35.2 v 32.4%, p=0.8); developed antibodies to infliximab (5.3 vs 11.3%, p = 0.09) or experienced drug related adverse events (7.8 vs 8.3%, p = 0.8) between switch and non-switch cohorts, at last follow-up.


Long-term infliximab persistence was similar between switch and non-switch cohorts after a median of 54 months. This study represent one of the longest ‘real-world’ comparisons between switch and non-switch cohorts specific to IBD, and should provide reassurance to clinicians and patients alike.