Asparaginase

Asparaginase is an enzyme that catalyzes the hydrolysis of asparagine to aspartic acid. It is also marketed under the brand names Elspar®, Oncaspar, and Erwinase to treat acute lymphoblastic leukemia (ALL) and is also used in some mast cell tumor protocols. Unlike other chemotherapy agents, it can be given as an intramuscular, subcutaneous, or intravenous injection without fear of tissue irritation.

Mechanism of action
The rationale behind asparaginase is that it takes advantage of the fact that ALL leukemic cells are unable to synthesize the non-essential amino acid asparagine whereas normal cells are able to make their own asparagine. These leukemic cells depend on circulating asparagine. Asparaginase however catalyzes the conversion of L-asparagine to aspartic acid and ammonia. This deprives the leukemic cell of circulating asparagine.

Side effects
The main side effect is an allergic or hypersensitivity reaction. Asparaginase has also been associated with pancreatitis. Additionally, it can also be associated with a coagulopathy as it decreases protein synthesis, including synthesis of coagulation factors and anticoagulant factor, leading to bleeding or thrombotic events such as stroke.