A Study of MAb-3F8 Plus Granulocyte-Macrophage Colony-Stimulating Factor (GM-CSF) Versus 13-cis-Retinoic Acid (RA) Plus GM-CSF in Primary Refractory Neuroblastoma Patients

Inclusion Criteria:

* Have a diagnosis of stage 4 neuroblastoma diagnosed in accordance with the International Neuroblastoma Staging System: either (a) histologic confirmation which may involve immunohistochemical, ultrastructural, and/or cytogenetic studies, or (b) elevated urinary catecholamines plus tumor cells/clumps in the bone marrow.
* Have evaluable disease or biopsy-proven stable disease in BM by histology or MIBG scan with MIBG-positive disease confined to the bone or bone marrow, plus urine catecholamine results, documented \>3 weeks after conventional chemotherapy or \>6 weeks after stem-cell transplantation. CT, MRI, or bone scan (if necessary) can be done at 2-3 weeks after conventional chemotherapy confirming that the chemotherapy, radiotherapy, and ABMT are not realistic curative options.
* Be between 18 months to 13 years old at diagnosis.
* Have recovered to grade 2 or better toxicities since their prior therapy.
* Must, if female of childbearing potential, be willing to use two forms of medically acceptable contraception (at least one barrier method) and have a negative pregnancy test at screening and monthly thereafter through the first four cycles of treatment.
* Have a performance score of at least 60 from Lansky Play Performance Scale if aged up to 16 years or at least 60 from Karnofsky Scale if aged more than 16 years.
* Have voluntarily agreed to participate.

Exclusion Criteria:

* Have measurable disease ≥ 1 cm assessed by CT or MRI.
* Have progressive disease (any new lesion; increase of any measurable lesion by \>25%; or previous negative marrow positive for tumor).
* Have disease detectable in CNS (confirmed by CT or MRI of the brain at screening or within 8 weeks of randomization).
* Be receiving alternative therapy for the treatment of neuroblastoma, e.g. radiotherapy or chemotherapy within 3 weeks of randomization.
* Require additional therapy (such as radiotherapy) during the first two treatment cycles.
* Have detectable human anti-mouse antibody titers at screening.
* Have received prior anti-GD2 investigational therapies.
* Have a history of allergies to mouse proteins.
* Have an active infection requiring IV infusion of antibiotics.
* Be currently receiving long-term chronic treatment with immunosuppressive drugs such as cyclosporine, adrenocorticotropic hormone (ACTH), or systemic corticosteroids.