Efficacy and safety of bispecific T-cell engager (BiTE) antibody blinatumomab for the treatment of relapsed/refractory acute lymphoblastic leukemia and non-Hodgkin's lymphoma: a systemic review and meta-analysis

Objectives: Multiple clinical trials have been conducted to investigate the therapeutic effects of blinatumomab on acute lymphoblastic leukemia (ALL) and non-Hodgkin's lymphoma (NHL). We did a meta-analysis including 8 clinical trials to verify the efficacy and safety of blinatumomab in patients with relapsed/refractory ALL and NHL. Methods: We searched and investigated all relevant publications from PubMed, Web of Science, Embase, and ClinicalTrials.gov. The primary endpoint was complete remission (CR). The secondary end points were the minimal residual disease (MRD) response, and the adverse effects including cytokine release syndrome (CRS) and grade >= 3 neurological events. Results: Our study showed that the pooled CR rate was 0.45 (95% CI: 0.37-0.53) in ALL and 0.20 (0.12-0.27) in NHL respectively. The pooled CR rate is higher in ALL patients with BM blasts <50% than that of patients with BM blasts >= 50% (0.75 versus 0.33). A history of allo-HSCT has no effect on the CR rate. The pooled MRD response rate was 0.42 (95% CI: 0.29-0.54) in ALL. For adverse effects, the pooled occurrence rate of grade >= 3 CRS was 0.04 (95% CI: 0.01-0.06), and the pooled occurrence rate of grade >= 3 neurological events was 0.12 (95% CI: 0.08-0.16). Discussion: Blinatumomab is effective in treating relapsed/refractory ALL and NHL. ALL patients manifested better therapeutic response than NHL patients and a reduced tumor load favored the clinical response. For adverse effects, severe CRS and neurological events did not happen very often. Conclusion: Blinatumomab shows valid therapeutic effects and limited adverse response in treating relapsed/refractory ALL and NHL in our meta-analysis