Amgen reports that the US Food and Drug Administration (FDA) has granted Breakthrough Therapy Designation to the company’s investigational bispecific T cell engager (BiTE) antibody blinatumomab, for adults with Philadelphia-negative (Ph-) relapsed/refractory B-precursor acute lymphoblastic leukemia (ALL), a rapidly progressing cancer of the blood and bone marrow.

Breakthrough Therapy Designation is intended to expedite the development and review of drugs for serious or life-threatening conditions. The criteria for Breakthrough Therapy Designation require preliminary clinical evidence that demonstrates the drug may have substantial improvement on at least one clinically significant endpoint over available therapy. A Breakthrough Therapy Designation conveys all of the fast-track program features, more intensive FDA guidance on an efficient drug development program, an organizational commitment involving senior managers, and eligibility for rolling review and priority review.

Bispecific T cell engager (BiTE) antibodies are a type of immunotherapy being investigated for use in fighting cancer by helping to engage 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 antibodies help place the T cells within reach of the targeted cell, with the intent of allowing it to inject toxins and trigger the cell to die (apoptosis). BiTE antibodies are currently being investigated for their potential to treat a wide variety of cancers.

Blinatumomab is an investigational BiTEantibody 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 antibodies and Amgen has received orphan drug designation from the FDA for the treatment of ALL, chronic lymphocytic leukemia (CLL), hairy cell leukemia, prolymphocytic leukemia and indolent B cell lymphoma and from the European Medicines Agency for the treatment of indolent B cell lymphoma, ALL, CLL and mantle cell leukemia (MCL). Blinatumomab is also being investigated for its potential to treat pediatric 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).

Source: Amgen