Zhu M, et al. - This trial dealt with the inquiry of blinatumomab pharmacokinetics, pharmacodynamics (CD3+ T-cell, CD19+ B-cell, and cytokine levels), and their associations with the efficacy or safety in relapsed/refractory acute lymphoblastic leukemia. T cell-mediated depletion of target B cells was found in blood and blasts in the bone marrow due to blinatumomab. Immune system effectiveness was crucial for the therapeutic responses.