• The proportion of patients with clinical response, defined as a decrease from baseline in the Mayo score by = 30% and = 3 points, with a decrease in the rectal bleeding subscore of = 1 or a rectal bleeding subscore of 0 or 1, at week 8.
  

• The proportion of patients in clinical remission defined as a Mayo score of = 2 points, with no individual subscore > 1 at week 8; Patients in remission by this definition will have a rectal bleeding subscore of either 0 or 1; mucosal heeling at week 8
  

This is a study designed to investigate the safety and effectiveness of a medication called infliximab (the active drug in (REMICADE®) in adult patients with active ulcerative colitis. The purpose of this study is to see if the symptoms of ulcerative colitis are lessened with this medication, infliximab, and what dose is needed to do that safely. Patients will receive infusions of either 5mg/kg, 10 mg/kg or placebo at weeks 0, 2, 6, and then once every 8 weeks thereafter through week 46 for up to 3 years.

Safety evaluations will be performed at specified intervals throughout the study and will consist of laboratory tests, vital signs (such as blood pressure), physical examinations and the occurrence and severity of adverse events as well as other study specific procedures. Patients will receive infusions of either 5mg/kg, 10 mg/kg or placebo at weeks 0, 2, 6, and then once every 8 weeks thereafter through week 46 for up to 3 years.