Fluorescence Imaging of Risankizumab-800CW in Inflammatory Bowel Disease

Inclusion Criteria for part A: * Established IBD diagnosis * Active disease: clinically active disease of the bowel is defined clinically as at least mild activity using dedicated scoring indices or biochemically active disease as defined by a fecal calprotectin \> 60 μg/g * Patients must be eligible for risankizumab therapy * Minimum age of 18 years * Written informed consent * Clinical indication for an endoscopic procedure Inclusion Criteria for part B: * Established IBD diagnosis * Patients must be on risankizumab therapy for at least 14 weeks * Minimum age of 18 years * Written informed consent * Clinical indication for an endoscopic procedure Exclusion Criteria for part A: * A female study patient who is pregnant or provides breastfeeding * A female study patient of premenopausal age who does not use any reliable form of contraception at the time of risankizumab-800CW administration and the following 10 weeks * Medical or psychiatric conditions that compromise the patient's ability to give informed consent * Prior anti-IL23-specific therapy (IL23/IL12 combination therapy is not an exclusion criteria) * Active extra gastrointestinal manifestations of Crohn's disease (e.g. uveitis or pyoderma gangrenosum at vital locations) Exclusion Criteria for part B: * A female study patient who is pregnant or provides breastfeeding * A female study patient of premenopausal age who does not use any reliable form of contraception at the time of risankizumab-800CW administration and the following 10 weeks * Medical or psychiatric conditions that compromise the patient's ability to give informed consent * Active extra gastrointestinal manifestations of Crohn's disease (e.g. uveitis or pyoderma gangrenosum at vital locations)