This trial evaluates the ability of a biologically active therapy in blinatumomab, an anti-CD19/CD3 bispecific T-cell engager, to further reduce the risk of leukemia relapse following HCT to improve post-HCT outcomes. The investigators will also utilize an alpha-beta T-cell and B-cell depleted graft to reduce the risk of GVHD along with a reduced intensity conditioning regimen without the use of TBI in patients who are minimal residual disease (MRD) negative using high throughput sequencing (HTS) prior to HCT. For those patients who remain HTS-MRD positive, a myeloablative conditioning regimen will be utilized, also followed by blinatumomab. This multi-institutional pilot study will be limited to 25 (estimated 10-15 per stratum) evaluable children, adolescents and young adults with B-ALL, that have experienced a relapse or have high-risk disease.
This trial will assess the feasibility of alpha/beta T-cell and B-cell depleted allogeneic hematopoietic cell transplantation (HCT) followed by blinatumomab therapy for high-risk B cell acute lymphoblastic leukemia (ALL) as a means of reducing rates of subsequent relapse and improving survival, while also minimizing treatment-related morbidity/ mortality and late effects. The conditioning regimens will be dependent on the patient's minimal residual disease (MRD) status prior to HCT using high throughput sequencing.