A new drug, asparaginase Erwinia chrysanthemi (Erwinaze), has been approved for the treatment of acute lymphoblastic leukemia (ALL). Erwinaze is intended for patients with ALL who've become allergic to the Escherichia coli-derived asparaginase and pegaspargase, the established chemotherapies for ALL.

Asparagine is a nonessential amino acid needed for the production of protein and to support cell growth. Although asparagine is taken into the body through dietary sources (such as asparagus), it's primarily produced endogenously, via several pathways, through biosynthesis. Although normal cells can make enough asparagine to support their survival, leukemia cells don't have the ability to create it. When Erwinaze is injected directly into the muscle (three times per week), it breaks down the asparagine, and without this nonessential amino acid, the leukemia cells die.

Erwinaze can cause allergic reactions, including anaphylaxis, which has occurred in approximately 5% of patients. Severe or hemorrhagic pancreatitis is also possible and has been seen in about 4% of patients receiving Erwinaze. If either occurs, Erwinaze should be discontinued. Other common adverse effects (appearing in at least 1% of patients) are abnormal transaminase levels; coagulation abnormalities, including thrombosis and hemorrhage; nausea and vomiting; and hyperglycemia. Hyperglycemia can become permanent and require insulin therapy. If the patient has a history of serious pancreatitis, hemorrhage, or thrombosis with asparaginase therapy, Erwinaze shouldn't be administered.

Nurses administering Erwinaze should follow the label instructions for reconstitution and administration and monitor the patient after administration for allergic reactions and signs of anaphylaxis. They should assess the patient's laboratory values carefully while the patient is receiving Erwinaze for elevated transaminase levels, abnormal clotting times, and elevated glucose levels and monitor for signs and symptoms of pancreatitis, such as abdominal pain; thrombosis (headache, leg pain, chest pain, shortness of breath, or arm or leg swelling); and hemorrhage (bleeding of the gums, blood in the urine or stool, or abdominal pain). Teach patients to be alert to the need for frequent urination and increased thirst, and instruct them to contact the prescriber if they arise. For the complete prescribing information, go to http://1.usa.gov/w0HuQs.