The effectiveness of blinatumomab in clearing measurable residual disease in pediatric B‐cell acute lymphoblastic leukemia patients detected by next‐generation sequencing

Abstract Background Blinatumomab improved survival outcomes in B‐cell acute lymphoblastic leukemia (B‐ALL) patients with measurable residual disease (MRD) <10 −4 . However, data on blinatumomab clearing MRD with high sensitivity of 10 −6 remain scarce. This study evaluates the effectiveness of blinatumomab in eradicating extremely low level (up to <10 −6 ) of MRD, as detected by next‐generation sequencing (NGS), in children with B‐ALL. Methods Patients ( n = 19) whose MRD was undetectable by multiparameter flow cytometry (MFC) (sensitivity of 10 −4 ) but detectable by NGS after chemotherapy and followed by blinatumomab consolidation were included retrospectively. Results After one course of blinatumomab, 13/19 patients (68%) successfully achieved NGS‐MRD clearance (undetectable). With a median follow‐up of 13.3 months, three of patients who were NGS‐MRD positive relapsed within 1.8 months, while another three remained complete remission. Conclusions Our study was the first to demonstrate that blinatumomab could further eradicate MRD after patients achieve MFC‐MRD undetectable in B‐ALL patients.