Amgen has submitted a Biologics License Application (BLA) to the US Food and Drug Administration (FDA) seeking approval for its investigational bispecific T cell engager (BiTE) antibody construct, blinatumomab. The BLA is for the treatment of adults with Philadelphia-negative (Ph-) relapsed/refractory B-precursor acute lymphoblastic leukaemia (ALL), a rapidly progressing cancer of the blood and bone marrow.

BiTE antibody constructs represent an innovative immunotherapy approach that helps the body's immune system target cancer cells. Blinatumomab, the first of the BiTE antibody constructs, has received both orphan drug designation and breakthrough therapy designation from the FDA for the treatment of ALL. The FDA states that breakthrough therapy designation, which is intended to expedite review of drugs for serious or life-threatening conditions, requires preliminary clinical evidence that demonstrates the drug may have substantial improvement over available therapies on at least one clinically significant endpoint.

"We look forward to working with regulatory authorities to make blinatumomab available for adult patients with acute lymphoblastic leukemia, who experience high relapse rates and have limited treatment options," said Sean E. Harper, M.D., executive vice president of research and development at Amgen. "The filing for blinatumomab brings us a step closer to first realizing the potential of BiTE technology and represents our commitment to evaluating this novel approach in a broad range of difficult-to-treat cancers."

The submission includes data from a phase 2 trial of adult patients with Ph- relapsed/refractory B-precursor ALL treated with blinatumomab, which successfully met its primary endpoint.

"Currently, there is no broadly accepted standard treatment regimen for adult patients with relapsed or refractory ALL," said Anthony S. Stein, M.D., clinical professor, Hematology/Oncology at City of Hope. "Blinatumomab has the potential to significantly advance treatment options for patients living with this difficult-to-treat disease, and the BLA submission marks an important step toward achieving this goal."  

In the US, it is estimated that more than 6,000 cases of ALL will be diagnosed in 2014, and in the European Union, more than 7,000 cases of ALL are diagnosed each year. In adult patients with relapsed or refractory ALL, median overall survival is just three to five months.

Bispecific T cell engager (BiTE) antibody constructs are a type of immunotherapy being investigated for fighting cancer by helping the body's immune system to detect and target malignant cells. The modified antibodies are designed to engage two different targets simultaneously, thereby juxtaposing T cells (a type of white blood cell capable of killing other cells perceived as threats) to cancer cells. BiTE antibody constructs help place the T cells within reach of the targeted cell, with the intent of allowing T cells to inject toxins and trigger the cancer cell to die (apoptosis). BiTE antibody constructs are currently being investigated for their potential to treat a wide variety of cancers.

Blinatumomab is an investigational BiTE antibody construct designed to direct the body's cell-destroying T cells against target cells expressing CD19, a protein found on the surface of B-cell derived leukemias and lymphomas. Blinatumomab is the first of the BiTE antibody constructs and Amgen has received orphan drug designation from the FDA for the treatment of ALL, chronic lymphocytic leukaemia (CLL), hairy cell leukaemia, prolymphocytic leukaemia and indolent B-cell lymphoma and from the European Medicines Agency for the treatment of indolent B-cell lymphoma, ALL, CLL and mantle cell leukaemia (MCL). Blinatumomab is also being investigated for its potential to treat paediatric relapsed/refractory ALL, relapsed/refractory Philadelphia positive (Ph+) B-precursor ALL, minimal residual disease positive (MRD+) B-precursor ALL, relapsed/refractory non-Hodgkin's lymphoma (NHL), including relapsed/refractory diffuse large B-cell lymphoma (DLBCL).

Acute lymphoblastic leukaemia (ALL) is an aggressive cancer of the blood and bone marrow, the spongy tissue inside bones where blood cells are made. The disease progresses rapidly and affects immature blood cells. Worldwide, ALL accounts for more than 12 per cent of leukaemia. Of the 42,000 people diagnosed worldwide, 31,000 will die from the disease. Patients with ALL have abnormal white blood cells (lymphocytes) that crowd out healthy white blood cells, red blood cells and platelets, leading to infection, anaemia (fatigue), easy bleeding and other serious side effects.

Amgen is committed to unlocking the potential of biology for patients suffering from serious illnesses by discovering, developing, manufacturing and delivering innovative human therapeutics.