Methods
We performed a retrospective analysis of all patients who received
multiple infusions of a non-humanized CD19-directed 4-1BB CAR-T,
tisagenlecleucel, at Cincinnati Children’s Hospital Medical Center
between January 2018 and December 2021. This study was approved by the
Cincinnati Children’s Hospital Medical Center Institutional Review
Board. A comprehensive review of patient, disease, and product
characteristics, toxicities, and patient outcomes was performed.
Cytokine release syndrome (CRS) and immune effector cell-associated
neurotoxicity syndrome (ICANS) were graded according to the American
Society of Transplantation and Cellular Therapy consensus
guidelines.16 Remission status was tested via
multiparametric flow cytometry on bone marrow samples collected 28 days
following CAR-T infusion, as well as morphological cerebrospinal fluid
(CSF) analysis via lumbar puncture. BCA was monitored at least monthly
by peripheral blood analysis of lymphocyte subpopulations. Loss of BCA
was defined as >1% CD19+ or 100 absolute CD19+ cells on
peripheral analysis, confirmed on a subsequent sample.