Study of Sargramostim in Moderately to Severely Active Crohn's Disease

Inclusion Criteria: * Confirmed diagnosis of Crohn's disease (endoscopic or radiological evaluation) at least 4 months prior to receiving the first dose of study drug * Moderately to severely active Crohn's disease at time of screening (i.e., Crohn's disease activity index \[CDAI\] \>220 and \<475 points) Exclusion Criteria: * Colostomy or ileostomy * Immediate need for gastrointestinal (GI) surgery for active GI bleeding, peritonitis, intestinal obstruction, or intra-abdominal or perianal abscess requiring surgical drainage * GI surgery within 6 months prior to receiving the 1st dose of study drug * Symptoms of bowel obstruction or confirmed evidence of a clinically-significant stricture within the last 6 months that has not been surgically corrected