pegaspargase: clinical use

Prescribing considerations

• Restrict prescribing and administration to experienced anticancer teams in a hospital with resuscitation facilities.
• Use SmPC-recommended premedication and post-administration observation because anaphylaxis may occur.
• Record the product name and batch number for biological-medicine traceability.
• Consider serum or plasma asparaginase activity where neutralising antibodies or accelerated inactivation are suspected.
• Assess previous asparaginase hypersensitivity, thrombosis, bleeding, pancreatitis and hepatic disease before treatment.

Contraindications and cautions

• Hypersensitivity to pegaspargase or an excipient
• Severe hepatic impairment as defined in the SmPC
• History of pancreatitis
• History of serious thrombosis following L-asparaginase therapy
• History of serious haemorrhage following L-asparaginase therapy

Monitoring

• Clinical observation for hypersensitivity during and after administration
• Coagulation parameters, fibrinogen and antithrombin activity at baseline and periodically during and after treatment
• Liver function, including bilirubin, and assessment for hepatic veno-occlusive disease
• Amylase and/or lipase, with prompt investigation of symptoms suggesting pancreatitis
• Blood glucose; consider closer monitoring with glucocorticoids
• Full blood count, infection status and treatment response
• Serum ammonia if compatible neurological or gastrointestinal symptoms develop
• Clinical signs of thrombosis, bleeding, osteonecrosis and central nervous system toxicity

Clinical pharmacology

Pegaspargase is polyethylene-glycol-conjugated, Escherichia coli-derived L-asparaginase. It hydrolyses L-asparagine to aspartic acid and ammonia, producing sustained asparagine depletion. Pegylation modifies pharmacokinetics and immunogenicity while retaining enzymatic activity.

Formulation and product differences

• The selected UK product is a white to off-white powder requiring aseptic reconstitution before intravenous or intramuscular administration.
• After reconstitution, only a clear, colourless solution without visible particles should be used; the vial must be gently swirled rather than shaken.
• Potency should not be compared directly with other pegylated or non-pegylated asparaginase products.