Lymphocyte dynamics after chimeric antigen receptor T cell therapy

Chimeric antigen receptor T cell therapy (CAR-T) is potentially lifesaving for many patients with a variety of malignancies. Unlike most other treatment, CAR-T cells grow in vivo and may persist to provide long term disease control. Understanding the kinetics of their expansion and how this correlates with responses and toxicity has provided interesting insights into this form of therapy. These correlations are discussed together with strategies being evaluated to reduce toxicity. The long-term impact on disease control of glucocorticosteroids or cyclophosphamide used in patients who develop neurologic toxicity are at present unclear. Whether the CAR-T cells have to persist for a cure is also a concept that needs further study.