MOdel-informed precision dosing (MIPD) of ustekinumab and VEdolizumab in inflammatory bowel disease: protocol for an Independent randomised, controlled, multicentre Trial (MOVE-IT).

introductionBiologic therapies, such as vedolizumab (VDZ) and ustekinumab (UST), offer effective treatment options for inflammatory bowel disease. In spite of limited evidence, it is common practice to escalate the dosing regimen if clinical symptoms or biomarkers give suspicion of loss of response. This study aims to determine whether model-informed precision dosing (MIPD) can provide equal efficacy and possibly superior cost-effectiveness compared with symptom-based management. METHODS AND ANALYSIS: This study is an unblinded, randomised controlled trial, conducted at six centres in Denmark. A total of 166 patients diagnosed with Crohn's disease or ulcerative colitis who have been on stable VDZ or UST therapy for at least 3 months will be enrolled. Participants will be randomised to receive either continued symptom and biomarker-based dosing (control group) or dosing guided by therapeutic drug monitor using pharmacokinetic (PK) models together with PK-pharmacodynamic targets (=MIPD; intervention group). The primary endpoint is the fraction of patients in steroid-free remission at the end of the observation period. Secondary endpoints include mucosal healing, clinical remission, biochemical disease control, PK assessment and cost-effectiveness. ETHICS AND DISSEMINATION: The trial has been approved by the Danish Medicines Agency and The Medical Research Ethics Committee. No study-related procedures will take place before patients have signed written informed consent. Results will be published in peer-reviewed journals and presented at international conferences. TRIAL REGISTRATION NUMBERS: EUCT, 2024-517123-39-00; NCT06788340.