CAR-T cell therapy: concept and approved indications.

• A. Autologous T cells engineered to express chimeric antigen receptor targeting CD19; approved for relapsed/refractory B-cell ALL and certain B-cell lymphomas
• B. Allogeneic T cells; approved for AML
• C. NK cell therapy; approved for CLL
• D. Monoclonal antibody therapy against CD20

Answer: (A)

CAR-T cell therapy uses a patient’s own T cells that are collected, genetically engineered to express a chimeric antigen receptor targeting CD19 on B cells, and then expanded and reinfused after a brief period of lymphodepleting chemotherapy. This engineered receptor lets the T cells recognize and kill malignant B cells with high specificity. CD19 is a common target because it is present on most B-lineage cells, including many malignant ones, making this approach effective across several B-cell cancers.

The approved indications reflect its use in relapsed or refractory B-cell acute lymphoblastic leukemia and certain relapsed/refractory B-cell lymphomas after other therapies have failed. It is not a standard treatment for acute myeloid leukemia, chronic lymphocytic leukemia, or other non-B-cell malignancies, and it differs from monoclonal antibody therapies against CD20, which are non-genetic antibody-based approaches rather than T cells engineered to attack the cancer. While most approved CAR-T products use autologous T cells, research into allogeneic CAR-T and other cell types like NK cells is ongoing.