Blinatumomab is the first drug in a class known as bispecific T-cell engagers (BiTEs). The structure of blinatumomab involves bivalent bispecific antibody variable fragments linked together, lending different binding properties at either end of the molecule. In this case, one end binds CD3 on the cell surface of T cells, and the other end binds CD19 on the cell surface of B cells.280 The purpose of this interaction is to exert an immune response by bringing an activated T cell in close proximity to malignant B-cell precursors. Blinatumomab is approved for the treatment of Philadelphia chromosome–negative relapsed or refractory B-cell precursor acute lymphoblastic leukemia (B-ALL).281
Blinatumomab has been associated with severe neurologic complications. Early dose-finding studies were limited by neurotoxicity, with patients developing severe reactions over doses of 60 micrograms/m2.282 Overall, 50% of patients enrolled in blinatumomab studies had some neurotoxicity related to the drug.281 Encephalopathy, seizures, mental status changes, aphasia, and ataxia have all been reported.281 The FDA recommends that dose adjustment be considered for any patient experiencing a grade 3 adverse reaction, and that permanent discontinuation should be considered when a patient experiences seizures or grade 4 toxicity.281 Most symptoms resolve after discontinuation of the drug. The putative mechanism of toxicity is not well understood, and seminal studies controlled for CNS involvement with disease; however, there is evidence to suggest that CD19 can be partially expressed by central neurons in a subset of patients, particularly neurons localized to the language areas.Blinatumomab, sold under the brand name Blincyto, is a biopharmaceutical medication used as a second line treatment for Philadelphia chromosome-negative relapsed or refractory acute lymphoma leukemia. It belongs to a class of constructed monoclonal antibodies, bi-specific T-cell engagers (BiTEs), that exert action selectively and direct the human immune system to act against tumor cells. Blinatumomab specifically targets the CD19 antigen present on B cells. In December 2014, it was approved by the US Food and Drug Administration under the accelerated approval program; marketing authorization depended on the outcome of clinical trials that were ongoing at the time of approval.
Blinatumomab is given as a continuous IV infusion for 28 consecutive days per cycle involving a 24/7 infusion followed by a two week break from infusion. The dose depends on a patient’s actual body weight. Patients weighing over 45 kg should receive fixed doses while patients weighing less than 45 kg should receive doses based on their estimated body surface area.
Blinatumomab was originally approved to treat Philadelphia chromosome-negative relapsed or refractory B-cell precursor acute lymphoblastic leukemia in adults and children. It is approved by the US Food and drug Administration (FDA) for B-cell precursor acute lymphoblastic leukemia (ALL) in first or second complete remission with minimal residual disease greater than or equal to 0.1% as well as relapsed or refractory B-cell precursor ALLBlinatumomab is a bispecific T cell engager(BiTE) It enables a patient’s T cells to recognize malignant B cells. A molecule of blinatumomab combines two binding sites: a CD3 site for T cells and a CD19 site for the target B cells. CD3 is part of the T cell receptor. The drug works by linking these two cell types and activating the T cell to exert cytotoxic activity on the target cell. CD3 and CD19 are expressed in both pediatric and adult patients, making blinatumomab a potential therapeutic option for both pediatric and adult populations