Amgen announced that the European Commission (EC) has granted conditional marketing authorization for Blincyto (blinatumomab) for the treatment of adults with Philadelphia chromosome-negative (Ph-) relapsed or refractory B-precursor acute lymphoblastic leukemia (ALL).

ALL is a rare and rapidly progressing cancer of the blood and bone marrow. For adults with relapsed or refractory ALL, the median overall survival is just three to five months. It is estimated that the incidence of adults with Ph- relapsed or refractory B-precursor ALL in the European Union (EU) is approximately 900 patients per year.

"We are pleased the European Commission granted conditional marketing authorization for Blincyto," said Sean E. Harper, M.D., executive vice president of research and development at Amgen. "Blincyto has demonstrated efficacy in treating relapsed or refractory ALL, a very difficult-to-treat disease for which historically patients had limited therapeutic options. This approval represents an important milestone in immunotherapy research. Blincyto is the first clinical validation of the BiTE platform, a new and innovative approach that helps the body's own immune system fight cancer."

The conditional marketing authorization for Blincyto is based on results of two phase 2 studies, study '211 and '206. In the pivotal '211 trial, 42.9 per cent of patients achieved complete remission (CR) or CR with partial hematological recovery (CRh) with single-agent Blincyto.

The most serious adverse reactions that occurred during Blincyto treatment in the pivotal '211 trial included infections, neurologic events, neutropenia/febrile neutropenia, cytokine release syndrome and tumor lysis syndrome.

"We tested Blincyto in ALL, the most aggressive B-cell malignancy we know, and observed a clinically meaningful remission rate," said Max S. Topp, M.D., professor, Hospital of Wuerzburg, Germany. "This is the first major advance in more than two decades for patients with this hard-to-treat cancer."   

"The prognosis for adult patients with ALL who are refractory to treatment or experience relapse is poor, and Blincyto constitutes a new treatment option for these patients," said Herve Dombret, M.D., professor, University Paris, Hospital Saint Louis, Paris. "It is important for clinicians and patients to have more treatment options in this acute form of leukemia."

Approval from the EC grants a centralized conditional marketing authorization with unified labeling in the 28 countries that are members of the EU. Norway, Iceland and Liechtenstein, as members of the European Economic Area (EEA), will take corresponding decisions on the basis of the decision of the EC. Conditional license requires the license to be renewed every year and it will be converted to full standard license once post-licensing commitments have been fulfilled.

Blincyto was granted orphan drug designation by the European Medicines Agency in 2009 for the treatment of ALL.

Blincyto 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. Blincyto was granted breakthrough therapy and priority review designations by the US Food and Drug Administration, and is now approved in the US for the treatment of Ph- relapsed or refractory B-cell precursor ALL. This indication is approved under accelerated approval. Continued approval for this indication may be contingent upon verification of clinical benefit in subsequent trials.

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.