Phase 3, Multi-Center, Randomized, Double-Blind, Parallel-Arm, 52-Week Dose Comparison Study of the Efficacy and Safety of 25 mg QD and 50 mg QD of OPC-6335 Oral Tablets and 800 mg BID of Asacol® in the Maintenance of Ulcerative Colitis Remission

Objective(s):

This study will compare the safety and efficacy of 25 mg per day (QD) and 50 mg QD of OPC-6535 to 800 mg twice a day (BID) of Asacol® in the maintenance of remission in subjects with ulcerative colitis.

Subject Population:

• Subjects with ulcerative colitis currently in remission defined as rectal bleeding (RB) and flexible sigmoidoscopy (FS) scores of 0, on or off a stable dose of sulfasalazine or 5-ASA products for at least 6 weeks.
• Subjects must have had the diagnosis of ulcerative colitis established by prior colonoscopy or undergo colonoscopy in lieu of flexible sigmoidoscopy during the Screening Period.
• Subjects must have had treatment for a flare of ulcerative colitis, with symptomatic onset of remission occurring no more than 52 weeks from the Screening Period.
• Subjects may not have used corticosteroids, topical agents (corticosteroid or 5-ASA enemas, suppositories, foams), azathioprine, 6-mercaptopurine, or methotrexate within 6 weeks of the Screening Period. Upon entry, sulfasalazine and 5-ASA containing products will be discontinued.

Safety: Vital signs, ECGs, laboratory studies (including hematology, clinical chemistry, and urinalysis), and adverse events.