A Phase II Study With a Safety Run-In of the Addition of N-803 to a Chemoimmunotherapy Backbone for the Treatment of Patients With Relapsed or Refractory Neuroblastoma

Inclusion Criteria: Age \- Patients must be \< 30 at the time of enrollment on study. Diagnosis \- Patients must have had histologic verification of neuroblastoma or demonstration of neuroblastoma cells in the bone marrow with elevated urinary or serum catecholamines \[i.e., \> 2 x upper limit of normal (ULN)\], at the time of initial diagnosis. Disease Risk Group * Patients must have high-risk neuroblastoma according to COG risk classification at the time of study registration. Patients whose disease was initially considered low or intermediate risk but were then reclassified as high-risk neuroblastoma prior to enrollment are also eligible. Response to Prior Therapy (using INRC definitions) \- Patients must have at least ONE (recurrent/progressive, refractory, or persistent) of the following: * Recurrent/progressive disease after the diagnosis of high-risk neuroblastoma at any time prior to enrollment regardless of response to frontline therapy. (Note that this excludes patients initially considered low or intermediate risk that progressed to high-risk disease but have not progressed after the diagnosis of high-risk neuroblastoma). * Refractory disease: A best overall response of no response/stable disease since diagnosis of high-risk neuroblastoma AND after at least 4 cycles of induction therapy. * Persistent disease: A best overall response of partial response since diagnosis of high-risk neuroblastoma AND after at least 4 cycles of induction therapy Sites of Disease \- Patients must have at least ONE of the following (lesions may have received prior radiation therapy if they meet the other criteria listed below) based on institutional assessment: Bone Sites • MIBG avid tumors: patients must meet one of the following criteria: a. Patients with recurrent/progressive or refractory disease: i. Must have at least one MIBG avid bone site on planar imaging OR ii. Must have \> 2 lesions on SPECT/CT. A biopsy is not required unless the above imaging criteria are not met b. Patients with persistent disease: i. If a patient has 3 or more MIBG avid bone lesions, then no biopsy is required. ii. If a patient has only 1 or 2 MIBG avid bone lesion sites, then biopsy confirmation of neuroblastoma and/or ganglioneuroblastoma in at least one MIBG avid site present at the time of enrollment is required. Bone lesions may be biopsied at any time point prior to enrollment. * For MIBG non-avid tumors, patients must have at least an FDG-PET avid site and meet the following criteria: 1. Biopsy confirmation of neuroblastoma and/or ganglioneuroblastoma at any time prior to enrollment of at least one FDG-PET avid site. Bone Marrow \- Any amount of tumor cells in the bone marrow (including neuroblasts, mature and maturing ganglion cells) done at the time of study enrollment based on routine morphology and/or immunohistochemistry in at least one sample from bilateral aspirates and biopsies. NOTE: Patients with bone marrow disease only will be eligible if they have more than 5% disease involvement (documented neuroblastoma cells) in at least one sample from bilateral bone marrow biopsies. Soft Tissue Sites \- At least one soft tissue lesion that meets criteria for a TARGET lesion as defined by: * SIZE: Lesion can be accurately measured in at least one dimension with a longest diameter ≥ 10 mm, or for discrete lymph nodes ≥ 15mm on short axis. Lesions meeting size criteria will be considered measurable. * In addition to size, a lesion needs to meet ONE of the following criteria except for patients with parenchymal CNS lesions which will only need to meet size criteria: a. For MIBG avid tumors: lesion must be MIBG avid and meet one of the following criteria: i. For patients with recurrent/progressive or refractory disease: no biopsy is required ii. For patients with persistent disease: * If a patient has 3 or more MIBG avid soft tissue lesions, then no biopsy is required. * If a patient has only 1 or 2 MIBG avid soft tissue lesion sites) then biopsy confirmation of neuroblastoma and/or ganglioneuroblastoma in at least one MIBG avid site present at the time of enrollment is required. Soft tissue lesions may be biopsied at any time point prior to enrollment. b. For MIBG non-avid tumors patient must have at least one FDG avid site and meet the following criteria: i. Biopsy confirmation of neuroblastoma and/or ganglioneuroblastoma from a lesion at any time prior to enrollment of at least one FDG-PET avid site. ii. At least one non-target soft tissue lesion that is not measurable but had a biopsy positive for neuroblastoma and/or ganglioneuroblastoma at any time prior to enrollment OR is MIBG avid on planar imaging. Performance Status \- Patients must have Lansky (≤16 years) or Karnofsky (\>16 years) score of ≥50 (Appendix I). Note: Patients who are unable to walk because of paralysis, but who are up in a wheelchair, will be considered ambulatory for the purpose of assessing the performance score. Prior Therapy \- Patients must have fully recovered from the acute toxic effects of all prior chemotherapy, immunotherapy, or radiotherapy prior to study registration. Patients must not have received the therapies indicated below within the specified time prior to registration on this study as follows: Table 2: Prior Therapies List Type of Therapy Specified Time Period Additional Comments Myelosuppressive Chemotherapy ≤ 14 days This includes cytotoxic agents given on a low dose metronomic regimen as well as retinoids. Biologic Antineoplastic (anti-neoplastic agents)1 ≤ 7 days Monoclonal Antibodies ≤ 7 days or 3 half-lives whichever is longer, but no longer than 30 days (with recovery of any associated toxicities). Cellular Therapy (e.g., modified T cells, NK cells, dendritic cells, etc.) ≤ 21 days and with recovery of all associated toxicities Radiation Small port radiation ≤ 7 days Large field radiation therapy ≤ 12 weeks i.e., total body irradiation, craniospinal, whol