The U.S. Food and Drug Administration (FDA) has approved the supplemental Biologics License Application (sBLA) for blinatumomab (Blincyto) to include new data supporting the treatment of pediatric patients with Philadelphia chromosome (Ph)-negative relapsed or refractory B-cell precursor acute lymphoblastic leukemia (ALL). This indication is approved under accelerated approval, and continued approval may be contingent u‑pon verification of clinical benefit in subsequent trials.
The approval is based on results from the phase I/II study 205, an open-label, multicenter, single-arm trial. Study 205 evaluated the safety and efficacy of blinatumomab in 93 pediatric patients with relapsed or refractory B-cell precursor ALL (second or later bone marrow relapse, any marrow relapse after allogeneic hematopoietic stem cell transplantation, or refractory to other treatments, with > 25% blasts in bone marrow). Treatment in this study has been completed, and subjects are being monitored for long-term efficacy.
Blinatumomab is a bispecific CD19-directed CD3 T-cell engager (BiTE) antibody construct that binds specifically to CD19 expressed on the surface of cells of B-lineage origin and CD3 expressed on the surface of T cells. The drug was granted Breakthrough Therapy, Priority Review, and Orphan Drug designations by the FDA, and is now approved in the United States for the treatment of Ph-negative relapsed or refractory B-cell precursor ALL.
In November 2015, blinatumomab was granted conditional marketing authorization in the European Union for the treatment of adults with Ph-negative relapsed or refractory B-cell precursor ALL. ■