Case study : USFDA approval of Amgen leukemia drug blinatumomab

U.S. health regulators on Wednesday approved an Amgen Inc drug that helps the immune system fight a rare type of leukemia, more than five months ahead of the expected decision date.

The drug, blinatumomab, which will be sold under the brand name Blincyto, was approved to treat a form of acute lymphoblastic leukemia (ALL) for which there are few treatment options once a patient has relapsed.

The initial approval is for patients whose cancer has returned after treatment or did not respond to previous treatment, such as a stem cell transplant or chemotherapy.

The U.S. Food and Drug Administration had given blinatumomab both its breakthrough designation, used for what it sees as potentially important new medicines, and a priority review, which typically cuts the approval decision time to six months from the normal 10 to 12 months. The action date under the priority review had been May 19, 2015.

Blinatumomab (AMG103) is a drug that has anti-cancer properties. It belongs to a new 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.

The drug was developed by a German-American company Micromet, Inc. in cooperation with Lonza; Micromet was later purchases by Amgen, which has furthered the drug’s clinical trials. In July 2014, the FDA granted breakthrough therapy status to blinatumomab for the treatment of acute lymphoblastic leukemia (ALL).In October 2014, Amgen’s Biologics License Application for blinatumomab was granted priority review designation by the FDA, thus establishing a deadline of May 19, 2015 for completion of the FDA review process.

“Blincyto is being approved under the FDA’s accelerated approval program, which allows approval of a drug to treat a serious or life-threatening disease based on clinical data showing the drug has an effect … reasonably likely to predict clinical benefit to patients,” the agency said.

The program provides earlier patient access to promising new drugs while the company conducts further clinical trials to confirm the effectiveness of the medicine.

In a clinical trail used for the approval decision, 32 percent of patients achieved complete remission for nearly seven months after receiving the drug via infusion for four weeks.

“Immunotherapies, especially Blincyto with its unique mechanism of action, are particularly promising for patients with leukemia,” Richard Pazdur, head of FDA evaluation of cancer products, said in a statement.

Ref: 1. Press Release by Amgen, FDA Approves BLINCYTO™ (Blinatumomab) Immunotherapy for the Treatment of Relapsed or Refractory B-Cell Precursor Acute Lymphoblastic Leukemia, relaese date December 3rd, 2014. 2. Press Release by Amgen, Amgen’s BiTE® Immunotherapy Blinatumomab Receives FDA Priority Review Designation In Acute Lymphoblastic Leukemia, release date October 9th, 2014.