P0611Effectiveness and safety of ustekinumab biosimilar for Inflammatory Bowel Disease in real-world clinical practice: 1-year outcomes.

Abstract Background Biologic therapies, such as ustekinumab, have demonstrated efficacy and safety in inflammatory bowel disease (IBD), however their high cost has driven to the recent development and approval of biosimilars. The aim of our study was to evaluate the effectiveness and safety of the ustekinumab biosimilar in clinical practice. Methods Observational, prospective, single-center study including patients with inflammatory bowel disease (IBD) treated with the ustekinumab biosimilar (Uzpruvo® 90 mg subcutaneous) as maintenance therapy. Clinical and biochemical remission after the switch to the biosimilar was prospectively analyzed. Clinical remission was defined as a Harvey–Bradshaw Index (HBI) ≤ 4 for Crohn’s disease (CD) and a partial Mayo score (pMS) ≤ 2 for ulcerative colitis (UC). Biochemical remission was defined as a fecal calprotectin (FC) level 250 μg/g and a C-reactive protein (CRP) level 5 mg/L. Results A total of 79 patients with inflammatory bowel disease (IBD) who transitioned from originator ustekinumab (Stelara®) to its biosimilar (Uzpruvo®) during maintenance therapy were included in the study. Baseline characteristics of the study population are summarized in image 1. Data were analyzed using the Friedman test for related samples with a two-way rank analysis of variance, revealing no statistically significant post-switch differences (Image 2). Regarding clinical remission, among patients with Crohn’s disease (CD), the median Harvey–Bradshaw Index (HBI) with originator ustekinumab was 4 (IQR, 3–5), which decreased to 3 (IQR, 2–4) after the switch to the biosimilar (p = 0.006). Among patients with ulcerative colitis (UC), the median partial Mayo score (pMS) was 3 (IQR, 1–3.3) while on Stelara®, remaining stable at 2 (IQR, 0.8–4) after the transition to the biosimilar (p 0.999) (Image 2). With respect to biochemical response, the median fecal calprotectin (FC) concentration before the switch was 135.5 μg/g (IQR, 45–374), and it remained at 112 μg/g (IQR, 56–260) after the switch (p 0.999). Similarly, no significant differences were observed in C-reactive protein (CRP) levels (Image 2). The follow-up period was 12 months, and no serious adverse events, either systemic or local at the injection site, were reported. Conclusion In our study, patients with inflammatory bowel disease (IBD) treated with originator ustekinumab (Stelara®) who transitioned to the ustekinumab biosimilar (Uzpruvo®) maintained both clinical and biochemical remission, with a comparable safety and tolerability profile. These findings suggest that the biosimilar is a reliable well-tolerated therapeutic alternative to the reference product, providing an opportunity for substantial cost savings without compromising efficacy or safety. References: 1. D’Amico F, Bencardino S, Gonçalves A, Allocca M, Furfaro F, Zilli A, Parigi TL, Fiorino G, Peyrin-Biroulet L, Danese S. Unlocking hope: the future of ustekinumab biosimilars in Crohn’s disease treatment. United European Gastroenterol J. 2025 Mar;13(2):186-200. doi:10.1002/ueg2.12682. Epub 2025 Feb 18. PMID: 39967304; PMCID: PMC11975607. 2. Cheon JH, Duk Ye B, Armuzzi A, Rieder F, Girolomoni G, Puig L, Jung H, Feldman SR. The ‘totality of evidence’ and ‘extrapolation’ of SB17, a ustekinumab biosimilar. Expert Opin Biol Ther. 2025 Jun;25(6):615-632. doi:10.1080/14712598.2025.2508838. Epub 2025 May 25. PMID: 40396611. 3. Lichtenstein GR, Loftus EV, Afzali A, Long MD, Barnes EL, Isaacs KL, Ha CY. ACG Clinical Guideline: Management of Crohn’s Disease in Adults. Am J Gastroenterol. 2025 Jun 3;120(6):1225-1264. doi:10.14309/ajg.0000000000003465. PMID: 40701562. Conflict of interest: Lobo Lucena, Beatriz: No conflict of interest Valdes, Teresa: none Van de Wiel Fernández, Sandra: No conflict of interest Maldonado Pérez, María Bélen: No conflict of interest Belvis Jiménez, María Inmaculada: No conflict of interest Argüelles Arias, Federico: No conflict of interest