Effectiveness and safety of adalimumab biosimilar in bio-naive patients with inflammatory bowel disease: a real-life multicenter observational study comparing ABP501, SB5, MSB11022, GP2017, and FKB327

Background Biosimilars represent a significant opportunity in the treatment of inflammatory bowel disease (IBD). Our aim is to assess the effectiveness and safety of the five approved adalimumab (ADA) biosimilars in IBD patients naive to biologics. Methods IBD patients naive to biologics from eight Spanish hospitals were enrolled. We included patients who started ADA biosimilars between November 2018 and January 2022. The study endpoints included (1) induction of remission at week 8; (2) drug persistence at the conclusion of the follow-up period; and (3) safety of the five ADA biosimilars. Results In total, 383 patients were included. After induction, 63.8% of patients were in clinical remission. In total, 114 (29.8%) patients discontinued treatment during follow-up. Clinical remission was maintained in 78.4% of patients after a median follow-up of 18 (12-24) months. Dose intensification was performed in 35 (9.1%) patients during follow-up. There was no significant difference in effectiveness for the 5-ADA biosimilars. Additionally, drug persistence was significantly higher in Crohn’s disease (CD) patients (P = .012), in the group of patients co-treated with immunomodulators (IMM) (P = .001) and in patients with post-induction (at week 8) ADA levels ≥ 7 μg/mL (P = .002). Adverse events were reported in 30 (7.8%) patients with no significant difference between ADA biosimilars. Conclusion ADA biosimilars are safe and effective in inducing and maintaining remission in a real-life population of bio-naive IBD patients. Furthermore, there is no significant difference between the 5-ADA biosimilars. Drug persistence was significantly higher in patients with CD treated with IMM and with post-induction ADA levels ≥7 μg/mL.