However, the therapeutic landscape of B-ALL has been fundamentally changed by the emergence of the novel immunotherapies: Blinatumomab, a CD3-CD19 bi-specific T cell engager, Inotuzumab, a chalicheamicin-bound anti-CD22 monoclonal antibody (mAb) and tisagenlecleucel, a CD19-specific chimeric antigen receptor modified T cell (CAR-T) therapy, all of which have induced complete remissions and even measurable residual disease (MRD) negativity in up to 80% of R/R patients (Khazal and Kebriaei, 2020). Here, CD19 is linked to acute lymphoblastic leukemia.