Phase 3 Trial of Blinatumomab vs Standard Chemotherapy in Pediatric Subjects With HIgh-Risk (HR) First Relapse B-precursor Acute Lymphoblastic Leukemia (ALL)

B-precursor ALL is an aggressive malignant disease. Therapy is usually stratified according to risk characteristics to ensure that appropriate treatment is administered to patients with high-risk of relapse. In general, pediatric treatment regimens are more intense than those employed in adults and include courses of combination chemotherapy. Standard of care chemotherapy is associated with considerable toxicity. There is a lack of novel treatment options for subjects who relapse or are refractory to treatment. Therefore, innovative therapeutic approaches are urgently needed. Blinatumomab is a bispecific single-chain antibody construct designed to link B cells and T cells resulting in T cell activation and a cytotoxic T cell response against CD19 expressing cells. This study will evaluate the event-free survival (EFS) after treatment with blinatumomab when compared to standard of care (SOC) chemotherapy. The effect of blinatumomab on overall survival and reduction of minimal residual disease compared to SOC chemotherapy will also be investigated.

Patients will be randomized in a 1:1 ratio to receive either one cycle of blinatumomab or one block of standard high-risk consolidation chemotherapy. Blinatumomab is administered as a continuous intravenous infusion (CIVI). One cycle of blinatumomab treatment includes 4 weeks of CIVI of blinatumomab. After completing consolidation therapy, the patients should undergo alloHSCT depending on their bone marrow status. The patients will be followed up until the last subject on study is 36 months following alloHSCT or has died, whichever is first.