Autologous CD19-directed CAR T-cell therapy. Patient T cells are engineered ex vivo to express a chimeric antigen receptor targeting CD19 and are administered as a single intravenous infusion (0.2–2 million cells/kg) after lymphodepleting chemotherapy to promote expansion. The CAR engages CD19 on B-lineage cells to trigger T-cell activation, proliferation, and cytotoxic killing of malignant CD19+ cells, with expected on-target B-cell aplasia.