White blood cells (Lymphocytes) help the body fight infection, however acute lymphoblastic leukemia, also known as cancer of the white blood cells, is characterized by a production of excess lymphocytes in the bone marrow.

The U.S. FDA has just approved a new drug called Erwinaze (asparaginase Erwinia chrysanthemi), manufactured by EUSA Pharma Inc. of Langhorne, which is designed for treatment in patients with acute lymphoblastic leukemia (ALL) who have a hypersensivity to asparaginase and pegaspargase chemotherapy drugs derived from E.coli for treatment of ALL.

Erwinaze is designed to break down amino acid (asparagine), one of the body’s protein building blocks in the blood, necessary for the growth of all cells. Erwinaze treatment consists of three intramuscular injections per week and causes leukemia cells to die. Erwinaze therapy does not affect healthy human cells that are able to produce sufficient asparagines for their own needs through biosynthesis, but Leukemia cells are unable to produce asparagines.

Richard Pazdur, M.D., director of the Office of Hematology and Oncology Products in the FDA’s Center for Drug Evaluation and Research commented:

“The approval of Erwinaze underscores the FDA’s commitment to the approval of drugs for conditions with limited patient populations with unmet medical needs using novel trial endpoints.”

Researchers assessed the safety and efficacy of Erwinaze in a clinical trial involving 58 patients. Additional safety data from 843 patients was obtained from an expanded access program called Erwinaze Master Treatment Protocol (EMTP). Patients in both studies had to discontinue pegaspargase or asparaginase treatment derived from E. coli due to allergic reactions.

The trial’s efficacy endpoint was the number of patients with sustained asparaginase activity levels that were associated with better leukemia control and survival. Researchers noted that the pre-specified threshold for asparaginase activity at 48 or 72 hours after dosing was maintained in all evaluable patients.

Side effects linked to Erwinaze therapy include serious allergic reactions (anaphylaxis), high blood levels of liver enzymes (abnormal transaminases and bilirubin), bleeding (hemorrhage), blood clotting, inflammation of the pancreas (pancreatitis), nausea, vomiting, and high blood sugar (hyperglycemia).

The FDA approved two other products that contain asapargine specific enzyme for treating ALL in patients prior to Erwinaze’s approval, namely Elspar (asparaginase injection) and Oncaspar (pegaspargase), both of which are derived from E. coli.

Erwinaze, manufactured by EUSA Pharma Inc. of Langhorne, Pa.tronic radiation, and for regulating tobacco products, has been classed as an orphan drug, on the basis that less than 200,000 people are affected in the U.S.

Written by Petra Rattue