Efficacy and Safety Study of GED-0507-34-Levo for Treatment of UC

Inclusion Criteria: * Male or female aged 18 and over at the time of signing the informed consent. * Diagnosis of UC with a duration of at least 3 months prior to the Screening Visit. * MMS ≥ 4 to ≤ 8 (range: 0 - 9) prior to randomization in the study * Subjects are required to have a colonoscopy if one has not been performed within 12 months prior to the Screening Visit. * Subjects who have relapsed on maintenance therapy with doses of 5-ASA ≤ 2.4 g/day Exclusion Criteria: * Diagnosis of Crohn's disease, indeterminate colitis, ischemic colitis, microscopic colitis, radiation colitis, or diverticular disease-associated colitis. * UC restricted to the distal 15 cm or less (eg, ulcerative proctitis). * Subjects who have had surgery as a treatment for UC or who, in the opinion of the Investigator, are likely to require surgery for UC during the study. * Clinical signs suggestive of fulminant colitis or toxic megacolon. * Evidence of pathogenic enteric infection. * History of colorectal cancer or colorectal dysplasia. * Prior use of any TNF inhibitor (or any biologic agent). * Prior use of mycophenolic acid, tacrolimus, sirolimus, cyclosporine, or thalidomide. * Use of budesonide-MMx within the last 8 weeks. * Use of oral and/or IV corticosteroids within 2 weeks of the Screening Visit. * Use of immunosuppressants (azathioprine \[AZA\], 6-mercaptopurine \[6-MP\] or methotrexate \[MTX\]) within 8 weeks of the Screening Visit.