Asparaginase is an essential therapeutic in the treatment of acute lymphoblastic leukaemia (ALL) in children and adults. Currently, there are three asparaginase products in clinical use: native Escherichia coli asparaginase, Erwinia chrysanthemi asparaginase and PEG-asparaginase. One of the important side effects is the occurrence of hypersensitivity reactions, such as clinical allergy or silent inactivation that can lead to inactivation of asparaginase with a negative impact on the outcome of the patient. Therapeutic drug monitoring (TDM) has proven to be a valuable tool to monitor asparaginase activity and detect decreased or absent activity at an early stage. Therefore, many contemporary paediatric ALL protocols include TDM of asparaginase as standard of care. In this report, the background of asparaginase hypersensitivity and silent inactivation is described and a practical flowchart regarding the use and TDM of PEG- and Erwinia asparaginase for patients with ALL is introduced.

(BELG J HEMATOL 2022;13(6):236–42)