The feasibility of additional CD19‐targeted cellular therapy in relapsed/refractory B‐ALL with re‐emergence of CD19 antigen after prior CD19‐negative relapse

Abstract

The introduction of CD19-targeted immunotherapies with bispecific T-cell engagers (BiTE) and chimeric antigen receptor (CAR) T-cells has transformed the therapeutic paradigm in relapsed/refractory (R/R) B-cell acute lymphoblastic leukemia B-cell (ALL). While complete remission (CR) rates are high with CD19-targeted immunotherapies, a considerable proportion of R/R B-ALL patients treated with blinatumomab and CD19 CAR T-cell therapy will be either refractory or suffer relapse afterward. 1,2 Therefore, patients with R/R B-ALL will require additional salvage therapies during their disease course. Applying sequential CD19-targeted immunotherapies in R/R B-ALL has proven feasibility,

Sequencing antigen‐targeting antibodies and cellular therapies in adults with relapsed/refractory B‐cell acute lymphoblastic leukemia

“…Although some patients treated with blinatumomab will lose the expression of CD19 antigen posttherapy, 12,33,37,38,93 we have observed the reexpression of CD19 antigen in a fraction of these patients after treatment with inotuzumab or other targeted therapies. 97 Outcomes of CD19-targeting therapies in CD19 re-expressors after prior progression with a CD19-or CD19 low expressor subclone remain poorly characterized.…”