Therapeutic drug monitoring in inflammatory bowel disease : implementation, utilization, and barriers in clinical practice in Scandinavia

• Published in: Scandinavian Journal of Gastroenterology
• Main Authors: Bjørlykke, Kristin H, Jahnsen, Jørgen, Brynskov, Jørn, Molander, Pauliina, Eberhardson, Michael, Davíðsdóttir, Lóa Guðrún, Sipponen, Taina, Hjortswang, Henrik, Goll, Guro Løvik, Syversen, Silje Watterdal, Langholz, Ebbe, Jørgensen, Kristin K, Steenholdt, Casper
• Other Authors: Other departments
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2023
• Subjects: Meltingarlæknisfræði; Humans; Gastrointestinal Agents/therapeutic use; Drug Monitoring/methods; Immunologic Factors/therapeutic use; Inflammatory Bowel Diseases/drug therapy; Scandinavian and Nordic Countries; Sulfur Compounds/therapeutic use; Biological Products/therapeutic use; biologics; clinical implementation; drug levels; Therapeutic drug monitoring; antibodies; Gastroenterology; Norway; Iceland
• Online Access: https://hdl.handle.net/20.500.11815/4072; https://doi.org/10.1080/00365521.2022.2108684

Funding Information: JB Speaker-, educational- and advisory board consultancy fees and research grants from Abbvie, MSD, Pfizer, Takeda, BMS, Gilead and Janssen-Cilag. Funding Information: KHB funding from Akershus University Hospital and speaker for Janssen-Cilag. Publisher Copyright: © 2022 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group. BACKGROUND AND AIMS: Therapeutic drug monitoring (TDM) may optimize biologic and thiopurine therapies in inflammatory bowel disease (IBD). The study aimed to investigate implementation and utilization of TDM in Scandinavia. METHODS: A web-based questionnaire on the use of TDM was distributed to Scandinavian gastroenterologists via the national societies. RESULTS: In total, 297 IBD physicians prescribing biologic therapies, equally distributed between community and university hospitals, were included (response rate 42%) (Norway 118 (40%), Denmark 86 (29%), Sweden 50 (17%), Finland 33 (11%), Iceland 10 (3%)). Overall, TDM was applied during biologic therapies by 87%, and for TNF-inhibitors >90%. Among the users, reactive and proactive TDM were utilized by 90% and 63%, respectively. Danish physicians were significantly less inclined to use TDM compared to other Scandinavian countries; (58% vs 98%); OR 0.03 [0.01-0.09], p < 0.001). Reactive TDM was commonly applied at primary (74%) and secondary (99%) treatment failure. Proactive TDM was used by 80% during maintenance therapy and 56% during induction and more commonly utilized in Norway (p < 0.001), and by physicians managing >10 IBD patients/week (p = 0.005). TDM scenarios were interpreted in accord with available evidence but with discrepancies for proactive TDM. The main barriers to TDM were lack of guidelines (51%) and time lag between sampling and results (49%). TDM of thiopurines was routinely used by 87%. CONCLUSION: TDM of biologic and thiopurine therapies has been broadly implemented into clinical practice in Scandinavia. However, physicians call for TDM guidelines ...