Prognostic Value Of Delta Lymphocyte Index (Dlix) In Patients With Large B-Cell Lymphoma (Lbcl) Treated With Chimeric Antigen Receptor (Car) T-Cell Therapy

Introduction. The efficacy of CAR T-cell therapy in relapsed/refractory (r/r) LBCL has been associated with peak CAR T-cell expansion post-infusion. One of the critical factors that drives CAR T-cell expansion is the availability of homeostatic cytokines, such as IL-15, at the time of infusion. Consistent with this hypothesis, serum IL-15 levels have been associated with CAR T-cell therapy expansion and efficacy, higher levels favoring improved outcomes. Since induction of lymphodepleting conditioning (LDC) therapy results in decreased consumption of homeostatic cytokines and thereby increases their serum levels, we aimed to determine whether the magnitude of change in absolute lymphocyte count (ALC) pre- and post-conditioning, referred to as delta lymphocyte index (DLIx), impacts outcomes after CAR T-cell therapy in r/r LBCL.