N18 Ustekinumab biosimilar for Crohn’s disease, patients’ perspective - a prospective single centre cohort study

Abstract Background Since august 2024 ustekinumab (UST) biosimilars have become available for treatment of Crohn’s disease (CD) in Slovenia. We performed a prospective single centre cohort study on patient’s willingness to switch from originator to biosimilar UST and factors influencing the choice of sc applicator type. Methods All patients with CD treated with originator UST were offered a switch to biosimilar for subcutaneous (sc) application. Data on comparable effectiveness and safety of biosimilars was explained to patients in written form in accordance with EMA statement and opinion of The Health Insurance Institute of Slovenia. Patients completed a survey questionnaire regarding sc application, factors influencing the choice of sc applicator type and their decision regarding switching to biosimilar. Descriptive statistics was used for data analysis. Results 43 CD patients treated with UST were included. 22 (51.2%) were female, median age 52 (range 23-79) years, median duration of CD was 16 (range 2-40) years. Majority of patients (55.8%) were treated with UST in 2nd line and 21% in 1st line. 11 (25.6%) patients were anti-TNF naïve. In 26 (60.5%) patients UST dosing was optimised. When offered biosimilar 15 (34.9%) patients agreed to switch and 28 (65.1%) wanted to continue treatment with originator drug. Regarding payment, only 12 (27.9%) patients were willing to pay a possible surcharge to continue treatment with originator UST. 31 (73.8%) patients found application with the pen more suitable, 8 (19.1%) patients preferred the syringe, 3 (7.1%) patients had no preference. When asked which applicator would they wish to use in the future, 29 (67.4%) patients opted for the pen, 2 (4.7%) patients for the syringe and 12 (27.9%) patients did not mind either way (figure 1). Factors influencing the choice of applicator type (multiple answers were possible) are presented in table 1. Conclusion Almost 2/3 of our CD patients treated with UST did not agree to switch from originator to biosimilar, despite the recommendations of healthcare agencies and expected financial savings. Most patients chose the pen, the lack of which is the leading drawback of currently available biosimilars. Top three factors influencing patients’ choice of applicator type were easy handling, easy preparation and less painful application. Additional efforts must be invested in informing patients of the efficacy, safety and expected benefits of biosimilars. References: 1. D’Amico F, Peyrin-Biroulet L, Danese S. Benefits of Biosimilars in the Management of Patients with Inflammatory Bowel Disease: An International Survey. J Clin Med. 2024 May 24;13(11):3069. 2. Aljabri A, Soliman GM, Ramadan YN, et al. Biosimilars versus biological therapy in inflammatory bowel disease: challenges and targeting strategies using drug delivery systems. Clin Exp Med. 2025 Apr 5;25(1):107. 3. Bhat S, Kane SV. Clinical Guide to Navigating the Landscape of Biosimilars for Inflammatory Bowel Disease. Gastroenterol Hepatol (N Y). 2024 Jul;20(7):376-82. 4. Angyal A, Bhat S. Biosimilars in IBD: What Every Clinician Needs to Know. Curr Gastroenterol Rep. 2024 Mar;26(3):77-85. Conflict of interest: Ocepek, Andreja: No conflict of interest Grilič, Urška: No conflict of interest Klobasa, Karolina: No conflict of interest Kramberger, Alenka: No conflict of interest Bukovnik, Nejc: No conflict of interest Velkovski, Cvetanka: No conflict of interest Pernek, Robert: No conflict of interest Nikolic, Sara: No conflict of interest