Adherence of a 1.600 mg Single Tablet 5-ASA Treatment of Ulcerative Colitis

Several oral mesalazine (5-ASA) formulations exist, but the regimes require several tablets per day. Such regimens are not ideal and can interfere with normal daily activities of patients. Non-adherence has been associated with an increase in the risk of relapse and worse disease course; leading to a decrease in quality of life, an increase in societal and personal costs, and worst case increases the risk of colorectal cancer. Recently, a new formula for 5-ASA has been approved by the Danish Medicine Agency, with a single tablet regime per day. Primary purpose: • To investigate whether a simplified treatment regimen for 5- ASA (1600 mg as one tablet per day \[intervention\]) improves adherence with preserved remission rates compared to conventional therapy. Secondary purposes: * Compare levels of endoscopic, mucosal and histological inflammation in predicting risk of relapse between the intervention group and the conventional therapy group. * Investigate whether a simplified treatment regimen improves the disease course compared to the conventional therapy. * To assess the correlation between different endpoints and the disease courses, with the use of clinical, endoscopic, histological, self-reported and biochemical markers. * Improve, correlate and assess patient-reported outcomes in a prospective manner. * To establish a biobank of cases with quiescent/mild ulcerative colitis (UC) for identification of future biomarkers.