This is a randomized, placebo-controlled, double-blind, dose-ranging study followed by a placebo-controlled, double-blind, repeated-dose extension to evaluate the effectiveness and safety of anti-TNF chimeric monoclonal antibody (cA2) compared to placebo in the treatment of patients with active Crohn's disease. The primary efficacy outcome of the study is a comparison of the proportion of patients achieving a clinical response at the 4-week evaluation. Clinical response is defined as a reduction from baseline in the Crohn's Disease Activity Index (CDAI) score of at least 70 points. Additional measurements of effectiveness include the clinical response over time, the time to loss of response, clinical remission over time, and changes in the Crohn's Disease Activity Index (CDAI), Inflammatory Bowel Disease Questionnaire (IBDQ), Crohn's Disease Endoscopic Index of Severity (CDEIS) scores and C-reactive protein values.~Anti-TNF Chimeric Monoclonal Antibody (cA2) or placebo
The purpose of this study is to evaluate the effectiveness and safety of anti-TNF chimeric monoclonal antibody (cA2) compared to placebo in patients with active Crohn's disease.