Blinatumomab overcomes poor prognostic impact of measurable residual disease in pediatric high-risk first relapse B-cell precursor acute lymphoblastic leukemia
Abstract
BACKGROUND: Blinatumomab, a CD3/CD19 BiTE((R)) (bispecific T cell engager) molecule, was superior to high-risk third course consolidation chemotherapy (HC3) in prolonging event-free survival (EFS) in children with high-risk first relapse B-cell precursor acute lymphoblastic leukemia (B-ALL). Here, we report results from a post hoc measurable residual disease (MRD) analysis of this phase 3 study (NCT02393859).
PROCEDURE: Children >28 days and =5% and =10(-4) at baseline who achieved MRD remission after blinatumomab, 20 (91%) achieved MRD <10(-4) remission by day 15. Patients treated with blinatumomab had improved EFS and overall survival compared with those treated with HC3 independent of end-of-induction or baseline (end-of-second consolidation) MRD levels.
CONCLUSIONS: Blinatumomab was more efficacious than HC3 regardless of MRD status before treatment. These data support the role of blinatumomab in inducing deep MRD remission, negating the poor prognostic value of MRD.