Comparison of original and biosimilar infliximab (CTP-13) in biologic-naïve patients with Crohn's disease and ulcerative colitis: a retrospective, multicenter real-life study in Spain

Purpose: biosimilar infliximab (CTP-13) has been recently approved for the treatment of several immune-mediated inflammatory disorders, including inflammatory bowel disease (IBD). Comparative studies between this biosimilar and original infliximab in the real clinical practice are scarce. The objective of this study was to compare short and long-term safety and efficacy of original (O) and biosimilar infliximab (B-IFX) in biologic-naive, IBD patients in the real life clinical practice. Methods: a retrospective, multicentric study was performed in five Spanish hospitals. Consecutive IBD, biologic-naive patients from an historic cohort who initiated O-IFX from January 2013 were compared with biologic-naive patients, who started treatment with B-IFX since its approval in January 2015. The evaluation of efficacy was assessed after the induction phase, at week 14 and week 54 of treatment. Time to dose escalation or treatment persistence of both O-IFX and B-IFX was also considered. The appearance of serious adverse events was recorded. Results: two hundred and thirty-nine IBD biologic-naive patients who started with O-IFX or B-IFX were included: 153 patients were diagnosed with Crohn’s disease (95 treated with O- and 58 treated with B-IFX) and 86 with ulcerative colitis (40 received O- and 46 received B-IFX). At weeks 14 and 54, both O-IFX and B-IFX groups reached a similar clinical response and remission rates. Time to dose escalation, treatment persistence and safety profile were comparable between both groups. Conclusions: this long-term real-life experience provides additional evidence of the similarity of O- and B-IFX CTP-13 in terms of efficacy and safety in IBD patients.