Consolidation therapy with blinatumomab was found to improve event-free survival and have less toxicity than chemotherapy in children with high-risk, first-relapse B-cell acute lymphoblastic leukemia (B-ALL), according to the results of a phase 3 trial (ClinicalTrials.gov Identifier: NCT02393859). The trial results were recently reported in JAMA.
The trial enrolled 108 children with high-risk, first-relapse B-ALL from 47 centers in 13 countries. All patients underwent induction therapy and 2 blocks of consolidation therapy. For the third consolidation, patients were randomly assigned to treatment with either 1 cycle of blinatumomab or chemotherapy.
Enrollment stopped early because the prespecified criterion to declare benefit for blinatumomab was met. The trial also met its primary endpoint of event-free survival, with the events defined as relapse, death, second malignancy, or failure to achieve complete remission.
At a median follow-up of nearly 2 years, the blinatumomab arm had significantly fewer events than the consolidation chemotherapy arm (31% vs 57%; P <.001) and a 67% reduced likelihood of having an event (hazard ratio, 0.33; 95% CI, 0.18-0.61).
The blinatumomab arm also had a higher rate of minimal residual disease remission compared with the consolidation chemotherapy arm (90% vs 54%).
A lower incidence of serious adverse events was reported in the blinatumomab arm compared with the consolidation chemotherapy arm (24.1% vs 43.1%), with fewer grade 3 or worse adverse events (57.4% vs 82.4%).
Hematologic toxicities such as thrombocytopenia (18.5% vs 35.3%), neutropenia (16.7% vs 31.4%), anemia (14.8% vs 41.2%), and febrile neutropenia (3.7% vs 25.5%) were also less frequent for the blinatumomab arm compared with the consolidation chemotherapy arm. “Thus, blinatumomab may offer a safety benefit over intensive multidrug consolidation chemotherapy,” the study authors wrote.
Locatelli F, Zugmaier G, Rizzari C, et al. Effect of blinatumomab vs chemotherapy on event-free survival among children with high-risk first-relapse B-cell acute lymphoblastic leukemia; a randomized clinical trial. JAMA. 2021;325(9):843-854. doi:10.1001/jama.2021.0987