FDA approves sBLA for Blincyto to treat adults and children with B-cell precursor acute lymphoblastic leukemia in first or second complete remission with minimal residual disease.- Amgen.

Amgen announced that the FDA has approved the supplemental Biologics License Application (sBLA) for Blincyto (blinatumomab) for the treatment of adults and children with B-cell precursor acute lymphoblastic leukemia (ALL) in first or second complete remission with minimal residual disease (MRD) greater than or equal to 0.1 percent. This indication is approved under accelerated approval based on MRD response rate and hematological relapse-free survival (RFS). Continued approval for this indication may be contingent upon verification and description of clinical benefit in the confirmatory trials.

Blincyto is the first-and-only approved bispecific CD19-directed CD3 T cell engager (BiTE) immunotherapy, is now also the first-and-only therapy to be FDA -approved for MRD. MRD refers to the presence of cancer cells that remain detectable, despite a patient's having achieved complete remission by conventional assessment. MRD is only measurable through the use of highly sensitive testing methods that detect cancer cells in the bone marrow with a sensitivity of at least one cancer cell in 10,000 cells -- versus about one in 20 with a conventional microscope-based evaluation.

The accelerated approval is based on results from the Phase II single-arm BLAST study (n=86), which found that Blincyto converted most patients to an MRD-negative state after a single cycle of therapy. Blincyto met the primary endpoint, inducing a complete MRD response, which is no detectable MRD, in 81 percent of patients (95 percent CI: 71.6, 89.0). Median hematological RFS was 22.3 months. Safety results among MRD-positive patients were consistent with the known safety profile of Blincyto in relapsed or refractory B-cell precursor ALL. The most common adverse reactions (greater than 20 percent) were pyrexia, infusion related reactions, headache, infections (pathogen unspecified), tremor and chills.

Comment: The FDA -approved prescribing information for Blincyto includes a boxed warning for cytokine release syndrome and neurologic toxicities. Blincyto is also under a risk evaluation and mitigation strategy (REMS) program in the U.S.