Journal
BLOOD
Volume 129, Issue 1, Pages 100-104Publisher
AMER SOC HEMATOLOGY
DOI: 10.1182/blood-2016-05-718395
Keywords
-
Categories
Funding
- Hubertus Wald Foundation
Ask authors/readers for more resources
The CD19 antigen is a promising target for immunotherapy of acute lymphoblastic leukemia (ALL), but CD19(-) relapses remain a major challenge in about 10% to 20% of patients. Here, we analyzed 4 CD19(-) ALL relapses after treatment with the CD19/CD3 bispecific T-cell engager (BiTE) blinatumomab. Three were on-drug relapses, with the CD19(-) escape variant first detected after only 2 treatment courses. In 1 patient, the CD19(-) clone appeared as a late relapse 19 months after completion of blinatumomab treatment. All 4 cases showed a cellular phenotype identical to the primary diagnosis except for CD19 negativity. This argued strongly in favor of an isolated molecular event and against a common lymphoid CD19(-) progenitor cell or myeloid lineage shift driving resistance. A thorough molecular workup of 1 of the cases with early relapse confirmed this hypothesis by revealing a disrupted CD19 membrane export in the post-endoplasmic reticulum compartment as molecular basis for blinatumomab resistance.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available