Leukemia Treatment Granted Priority Review by FDA

Investigational bispecific T-cell engager antibody construct aids immune system in targeting cancer cells.

The FDA on Thursday granted a priority review for Amgen’s investigational leukemia bispecific T-cell engager (BiTE) antibody construct, blinatumomab.

The treatment provides a new option for adults with Philadelphia-negative relapsed/refractory B-precursor acute lymphoblastic leukemia (ALL), which attacks the blood and bone marrow.

The BiTE antibody constructs offer an innovative immunotherapy approach in aiding the body's immune system to target cancer cells. Blinatumomab, which is the first investigational BiTE antibody construct, received orphan drug designation, in addition to breakthrough therapy and priority review designation from the FDA for the treatment of ALL.

More than 6000 cases of ALL will be diagnosed in the US this year, while an estimated it is 7000 cases of ALL are diagnosed each year in the European Union. The median survival for relapsed or refractory ALL is just 3 to 5 months.

The immunotherapy BiTE antibody constructs are being evaluated in fighting cancer by aiding the immune system to detect and target malignant cells. The antibodies are designed to engage 2 targets simultaneously by juxtaposing T-cells to cancer cells, which helps place the T-cells adjacent to the targeted cell allowing the T-cells to inject toxins and trigger apoptosis.

The BiTE antibody constructs are currently being investigated for their potential to treat a wide variety of cancers.

Blinatumomab directs T cells against target cells that express the protein CD19, which is found on the surface of B-cell derived leukemias and lymphomas. The drug treats ALL, chronic lymphocytic leukemia CLL, hairy cell leukemia, prolymphocytic leukemia and indolent B-cell lymphoma.

Additionally, blinatumomab is being evaluated as a potential treatment for pediatric relapsed/refractory ALL, relapsed/refractory Philadelphia positive B-precursor ALL, minimal residual disease positive B-precursor ALL, relapsed/refractory non-Hodgkin's lymphoma, including relapsed/refractory diffuse large B-cell lymphoma.