Detectable measurable residual disease (MRD) is the most important prognostic factor for B-cell acute lymphoblastic leukemia (B-ALL) for overall survival (OS) and disease-free survival (DFS). Patients who are MRD positive and have no access to novel immunotherapies should receive an allogeneic hematopoietic stem cell transplantation (HSCT). Blinatumomab is considered a standard of care (SOC) for this group of patients, however, the ideal treatment dose for MRD is unknown as doses were adjusted from the relapsed/refractory setting. Preliminary data suggest short cycles of blinatumomab can also be effective in states of lower disease burden prior to transplant. Thus, the investigators are performing a phase 2 trial assessing 7 days of blinatumomab as a bridge to HSCT Primary endpoint is assessing the MRD response following a short-course blinatumomab infusion in patients with B-ALL with complete response (CR) and have detectable MRD disease who are candidates for HSCT. Secondary endpoints include incidence of adverse events, OS, DFS, percentage of patients who receive HSCT, incidence of cytokine release syndrome (CRS) and immune effector cell associated neurotoxicity syndrome (ICANS)