Abstract
Purpose: Current protocols for CD19 chimeric antigen receptor–expressing T cells (CD19.CAR-T cells) require recipients to tolerate preinfusion cytoreductive chemotherapy, and the presence of sufficient target antigen on normal or malignant B cells. Patients and Methods: We investigated whether additional stimulation of CD19.CAR-T cells through their native receptors can substitute for cytoreductive chemotherapy, inducing expansion and functional persistence of CD19.CAR-T even in patients in remission of B-cell acute lymphocytic leukemia. We infused a low dose of CD19.CAR-modified virus-specific T cells (CD19.CAR-VST) without prior cytoreductive chemotherapy into 8 patients after allogeneic stem cell transplant. Results: Absent virus reactivation, we saw no CD19. CAR-VST expansion. In contrast, in patients with viral reactivation, up to 30,000-fold expansion of CD19.CAR-VSTs was observed, with depletion of CD19þ B cells. Five patients remain in remission at 42–60þ months. Conclusions: Dual T-cell receptor and CAR stimulation can thus potentiate effector cell expansion and CAR-target cell killing, even when infusing low numbers of effector cells without cytoreduction.
Original language | English (US) |
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Pages (from-to) | 7340-7350 |
Number of pages | 11 |
Journal | Clinical Cancer Research |
Volume | 25 |
Issue number | 24 |
DOIs | |
State | Published - Dec 15 2019 |
Externally published | Yes |
All Science Journal Classification (ASJC) codes
- Oncology
- Cancer Research