First-line treatment of acute lymphoblastic leukemia with pegasparaginase.

Acute lymphoblastic leukemia (ALL) accounts for almost 4000 cases annually in the United States, approximately two thirds of which are in children and adolescents. Treatment results of ALL have improved considerably in the past decade, due to an optimal stratification of patients and a rational use of different antileukemic agents among which L-asparaginase (L-ASNase) plays a fundamental role. This drug has been used in pediatric ALL chemotherapy protocols for almost 3 decades. In the 1970s and 1980s a chemically modified form of this enzyme called pegasparaginase (PEG-ASNase) was rationally synthesized to decrease immunogenicity of the enzyme and prolong its half-life. The different advantages of PEG-ASNase have been demonstrated in many clinical studies, the last of which underline the utility of this drug in front-line therapy of ALL. In this review, we discuss the pharmacological advantages and clinical potential of PEG-ASNase and its important use in first-line treatment of ALL.