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 12months 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, microscopiccolitis, 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 theInvestigator, 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.