Safety and Efficacy Study in the Treatment of Pediatric Crohn's Disease

Inclusion Criteria: * Have a parent or guardian able to provide written informed consent * Be able to provide verbal or written assent depending on age * Age 6 to 16 years * Have confirmed diagnosis of Crohn's Disease at study time of study entry based on radiologic, endoscopic, or histologic evaluations * Have a PCDAI score \>/= 30 points * Have a negative serum pregnancy test within 7 days prior to receiving the first dose of sargramostim in female patients who, in the opinion of the investigator, are sexually active and of childbearing potential * Be able to self-inject sargramostim or have a designee who can do so * Available documentations of weight from 4 to 6 months prior to study entry Exclusion Criteria: * Existing colostomy or ileostomy * Immediate need of GI surgery for active GI bleeding, peritonitis, intestinal obstruction, or intra-abdominal or perianal abscess requiring surgical drainage * GI surgery within 3 month prior to receiving the first dose of sargramostim * Symptoms of bowel obstruction or confirmed evidence of a clinically significant stricture within the last 6 month that has not been surgically corrected * Use of any of the following medications within 4 weeks prior to receiving the first dose of study drug: 6 mercaptopurine, azathioprine, cyclophosphamide, methotrexate, mycophenolate mofetil, tacrolimus, cyclosporine, or thalidomide * Use of licensed/registered and/or experimental anti-tumor necrosis factor (TNF) therapy such as infliximab or adalimumab within 8 weeks prior to first dose of sargramostim * Use of any investigational drug within 4 weeks or 5 half-lives (whichever is greater) prior to receiving the first dose of sargramostim * Concurrent use of corticosteroid therapy for Crohn's Disease, which exceeds a dose of 60 mg/day (or equivalent) of prednisone * Inability to comply with protocol requirements or provide informed consent * Presence of clinically important comorbid condition(s) unrelated to Crohn's Disease * Prior use of recombinant human GM-CSF (sargramostim or molgramostim) or granulocyte colony-stimulating factor (G-CSF; filgrastim or pegfilgrastim) * Current use of nutritional therapy (i.e., tube feeding or elemental/polymeric diet) which provides \> 50% of daily caloric intake