Study of STA-5326 Mesylate in Patients With Moderate to Severe Crohn's Disease

Inclusion Criteria: * Is male or female aged 18 through 75 years. * Has Crohn's disease diagnosed definitively prior to Screening (based upon clinical, endoscopic, radiologic imaging, or histological assessments). * Has a Crohn's Disease Activity Index (CDAI) score of 220 to 450, inclusive at Baseline. Exclusion Criteria: * Has any clinically significant disease (eg, renal, hepatic, neurological, cardiovascular, pulmonary, endocrinologic, psychiatric, hematologic, urologic, or other acute or chronic illness) that, in the opinion of the investigator, would make the patient an unsuitable candidate for this study. * Is a woman who has a positive pregnancy test, who is breast-feeding, or who is sexually active without using birth control during the course of the study and Follow-Up period. * Is a woman of childbearing potential or a man who does not agree to use 2 forms of contraception during the course of the study and Follow-Up period. * Has clinically significant hematologic, hepatic or renal laboratory abnormalities.