‣ General:

• Male and female patients with UC and 18 to 80 years of age (at the time of signing the informed consent).

• Ability to understand and comply with the protocol.

• Signed written informed consent.

• Disease-specific:

• Documented diagnosis of UC, with a minimum disease duration of 3 months prior to screening and ≥ 1 relapse, clinically defined using established criteria within the last 12 months.

• Histology supportive for the diagnosis of UC.

• Mild to moderate disease activity (at screening): modified Mayo score (mMS) 4-7 RB ≥ 1, endoscopic score ES ≥1 and SF ≥ 1.

• RHI \> 4 (at screening endoscopy).

• Disease extent \>15 cm from the anal verge (at screening endoscopy).

• Elevated level(s) of C-reactive protein (CRP) and/or faecal calprotectin during the screening period (levels above the reference range, measured by local laboratories).

⁃ Full colonoscopy with no signs of malignancy either during screening or within one year before screening.

⁃ Medication:

⁃ In the case of no oral 5-aminosalicylate (5-ASA) therapy within the last 2 weeks before entry into screening with informed consent, any prior oral 5-ASA therapy is permitted and the patient is not allowed to receive 5-ASA during the study. In the case of oral 5-ASA therapy within 2 weeks before entry into screening with informed consent, the 5-ASA therapy should have been ongoing for \> 3 months and should be stable ≥ 4 weeks before screening endoscopy with ≤ 3 g/d (up to 3 days with \> 3 g/d acceptable). This 5-ASA baseline medication must be kept stable in the induction period and may be reduced (but not increased again) in the maintenance period.