biostudies-literaturePillai VNCI NIH HHS3539-3549https://www.ebi.ac.uk/biostudies/studies/S-EPMC6880911biostudies-literatureUnknown3(22)Tisagenlecleucel, a chimeric antigen receptor (CAR) T-cell product targeting CD19 is approved for relapsed/refractory B-cell acute lymphoblastic leukemia (B-ALL). However, the impact of pretreatment variables, such as CD19 expression level, on leukemic blasts, the presence of CD19- subpopulations, and especially prior CD19-targeted therapy, on the response to CAR T-cell therapy has not been determined. We analyzed 166 patients treated with CAR T-cell therapy at our institution. Eleven patients did not achieve a minimal residual disease (MRD)- deep remission, whereas 67 patients had a recurrence after achieving a MRD- deep remission: 28 patients with CD19+ leukemia and 39 patients with CD19- leukemia. Return of CD19+ leukemia was associated with loss of CAR T-cell function, whereas CD19- leBlood advancesCAR T-cell therapy is effective for CD19-dim B-lymphoblastic leukemia but is impacted by prior blinatumomab therapy.PMC6880911P30 CA016520P01 CA214278U01 CA232563Pillai VMuralidharan KCherian SOldridge DAMohan DRheingold SRMelenhorst JJMeng WBhoj VGDiNofia AMFromm JRPaessler MJune CHThomas-Tikhonenko ALuo MVan Arnam JBagashev AGrupp SAMaude SLRosenthal JLuning Prak ETWertheim GfalseCAR T-cell therapy is effective for CD19-dim B-lymphoblastic leukemia but is impacted by prior blinatumomab therapy.Tisagenlecleucel, a chimeric antigen receptor (CAR) T-cell product targeting CD19 is approved for relapsed/refractory B-cell acute lymphoblastic leukemia (B-ALL). However, the impact of pretreatment variables, such as CD19 expression level, on leukemic blasts, the presence of CD19- subpopulations, and especially prior CD19-targeted therapy, on the response to CAR T-cell therapy has not been determined. We analyzed 166 patients treated with CAR T-cell therapy at our institution. Eleven patients did not achieve a minimal residual disease (MRD)- deep remission, whereas 67 patients had a recurrence after achieving a MRD- deep remission: 28 patients with CD19+ leukemia and 39 patients with CD19- leukemia. Return of CD19+ leukemia was associated with loss of CAR T-cell function, whereas CD19- le2019-01-01T00:00:00Z2019 Nov2025-04-21T15:51:46.923Z2020-05-21T19:45:24ZS-EPMC68809113173883210.1182/bloodadvances.2019000692