Objective  To evaluate the short-term efficacy and safety of blinatumomab in the treatment of patients with B-cell acute lymphoblastic leukemia (B-ALL).

  Methods  Clinical and follow-up data for 21 patients with B-ALL who received blinatumomab from August 2021 to April 2022 at The First Affiliated Hospital of Soochow University and Soochow Hopes Hematonosis Hospital were retrospectively analyzed.

  Results  All 21 patients were followed up regularly with a median follow-up time of 5.1 (1.3–8.3) months. Of the 11 patients with relapsed or refractory (R/R) B-ALL, the complete response (CR) or CR with incomplete hematological recovery (CRi) rate was 45.5% and the minimal residual disease (MRD)-negative rate among patients with a CR or a CRi was 80.0%. All three patients with a MRD-positive CR or CRi achieved MRD negativity. Of the 14 MRD-positive patients, five patients received allogeneic hematopoietic stem cell transplantation (allo-HSCT) after blinatumomab treatment, and nine patients did not. The 6-month overall survival rates of the allo-HCST and non-allo-HCST groups were 100.0% and 76.0% (P=0.260), and the 2-month leukemia-free survival (LFS) rates were 80.0% and 33.0% (P=0.044), respectively. In addition, patients who received less than three times of chemotherapy had longer LFS than those who received three or more times of chemotherapy (P=0.001). All the patients experienced adverse events of any grade. Only one patient experienced grade 3 of cytokine release syndrome, but no fatal adverse events occurred.

  Conclusions  Blinatumomab achieved high treatment response rates in both R/R and MRD-positive B-ALL patients, which is conducive to early bridging transplantation after deep remission and prolonging leukemia free survival.