Testing the Combination of Two Immunotherapy Drugs (Magrolimab and Dinutuximab) in Patients With Relapsed or Refractory Neuroblastoma or Relapsed Osteosarcoma

Inclusion Criteria

• Patients must have a history of histologically or cytologically confirmed NBL or osteosarcoma
• Patients must have:
• Relapsed/refractory high-risk neuroblastoma (NBL) (defined as disease recurrence after completion of therapy, progressive disease on therapy, or refractory disease during induction therapy) or
• Relapsed osteosarcoma (relapsed after frontline therapy and/or there must not be any potentially curative treatment options available at the time of enrollment)
• Cohort B1: Confirmed neuroblastoma: measurable NBL/ganglioneuroblastoma (defined as those lesions that can be accurately measured in at least one dimension (longest diameter to be recorded) as >= 10 mm with cross sectional imaging (CT scan or MRI), or >= 10 mm with calipers by clinical exam). Chest x-ray cannot be used to determine eligibility. Lesions must be iobenguane (MIBG) positive, positron emission tomography (PET) avid (if patient has a history MIBG negative disease) or biopsy proven NBL/ganglioneuroblastoma
• Cohort B2: Evaluable NBL (MIBG and/or bone marrow disease only)
• Cohort B3: Measurable osteosarcoma (defined as those lesions that can be accurately measured in at least one dimension (longest diameter to be recorded) as >= 10 mm (>= 1 cm) with cross sectional imaging (CT scan, MRI, or calipers by clinical exam). Chest x-ray cannot be used to determine eligibility
• Cohort B4: Patients with relapsed resectable pulmonary osteosarcoma who are scheduled for a surgical resection
• Note: Subjects will not have measurable disease due to recently resected pulmonary metastases. Investigational therapy must begin within three weeks of resection. Staged resections are permissible; investigational therapy will be administered in between resections. Patients should receive one cycle of investigational therapy in between resections but can receive additional cycles to accommodate the most appropriate surgical schedule as determined by the treating physicians. Every effort will be made to have at least half of this cohort (five of ten patients) be those requiring a staged resection
• There is no limit to the number of prior treatment regimens. Patients must have fully recovered from the acute toxic effects of all prior chemotherapy, immunotherapy, or radiotherapy prior to initiation of study treatment. Acute toxicity of any previous therapy must have resolved to grade 1 or less or stabilized, unless specified elsewhere
• Myelosuppressive chemotherapy: Patients must not have received myelosuppressive chemotherapy within 3 weeks of initiation of study treatment (6 weeks if prior nitrosourea)
• Hematopoietic growth factors: At least 7 days must have elapsed since the completion of therapy with a growth factor. At least 14 days must have elapsed after receiving pegfilgrastim
• At least 7 days must have elapsed since the completion of therapy with a biologic agent, targeted agent, tyrosine kinase inhibitor or a metronomic non-myelosuppressive regimen
• At least 4 weeks must have elapsed since prior therapy with 131I-MIBG
• Monoclonal antibodies: At least 3 weeks must have elapsed since prior therapy that included a monoclonal antibody. Patients who have received prior therapy with GD2 antibodies, regardless of response to therapy, will be eligible
• At least 7 days must have elapsed since the last pharmacologic dose of systemic corticosteroids
• Arm A: Age >= 2 or = 2 or = 16 years of age: Karnofsky >= 50%; Subjects = = 50%
• Absolute neutrophil count >= 1,000/mcL
• Hemoglobin >= 9.5 g/dL, transfusion support acceptable
• Platelets >= 100,000/mcL, independent of transfusions
• Total bilirubin = = 70 mL/min/1.73 m^2
• Human immunodeficiency virus (HIV)-infected patients on effective anti-retroviral therapy with undetectable viral load within 6 months are eligible for this trial
• For patients with evidence of chronic hepatitis B virus (HBV) infection, the HBV viral load must be undetectable on suppressive therapy, if indicated
• Patients wi