Blincyto to treat lymphoblastic leukemia approved, carries boxed warning

FDA has approved blinatumomab (Blincyto, Amgen) immunotherapy for the treatment of relapsed or refractory Philadelphia chromosome-negative precursor B-cell acute lymphoblastic leukemia.

FDA drug approvals-December 2014

Precursor B-cell acute lymphoblastic leukemia (ALL) is an aggressive type of leukemia characterized by the presence of too many B-cell lymphoblasts, or immature white blood cells, in the bone marrow and peripheral blood. There are approximately 6020 new cases and 1440 deaths attributed to ALL so far in 2014. The Philadelphia chromosome (Ph1) is a genetic abnormality that occurs in about 25% of adult cases of ALL and carries a more dismal prognosis than Ph1-negative disease.

Blincyto is the first FDA-approved bispecific CD3/CD19 monoclonal antibody and the first single agent to be approved for the treatment of patients with Philadelphia chromosome-negative precursor B-cell ALL. Blincyto is a type of immunotherapy that works by linking­ B cells and T cells resulting in T cell activation and a cytotoxic T cell response against CD19-expressing cells.  It is intended for patients whose cancer returned after treatment or did not respond to previous treatment.

FDA granted Blincyto breakthrough therapy designation, priority review and orphan product designation and was approved more than five months ahead of the scheduled completion date due to clinical evidence suggesting the potential that the drug may offer a substantial improvement over current available therapies.

“The FDA’s breakthrough therapy designation and accelerated approval of Blincyto underscores the critical need for new treatment options for patients with relapsed or refractory B-cell precursor ALL, who are often young adults,” said Sean E. Harper, MD, executive vice president of Research and Development at Amgen. “Blincyto is the first clinical and regulatory validation of the BiTE platform, a new and innovative approach that helps the body’s own immune system fight cancer.”

Blincyto’s approval is based on results of a clinical trial to assess the safety and efficacy of the drug, which involved adult patients with Ph1-negative relapsed or refractory precursor B-cell ALL. Of the 185 patients evaluated, 41.6% achieved complete remission or complete remission with partial hematologic recovery within 2 cycles of treatment.

The most common side effects observed in clinical trials include flu-like symptoms, tremors, weight gain and hypokalemia. Blincyto carries a boxed warning regarding Cytokine Release Syndrome (CRS) and neurological toxicities and was approved with a Risk Evaluation and Mitigation Strategy (REMS) to ensure proper education of health care providers about the serious risks and the potential for preparation and administration errors. 

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Erin Bastick is a PharmD Candidate 2016, Ohio Northern University, Ada, Ohio, and an inpatient intern at University Hospitals, Cleveland.