Glucarpidase: prescribing and clinical use
Focused clinical detail for use alongside current product information, local policy and patient-specific assessment.
Glucarpidase: clinical details
Prescribing considerations
- Use under specialist supervision when plasma methotrexate elimination is delayed.
- Continue folinic acid rescue, hydration and urine alkalinisation; coordinate folinic acid administration to limit enzymatic degradation.
- Glucarpidase removes extracellular methotrexate but does not reverse established renal injury.
- Record the product name and batch number for traceability.
- Be prepared to manage acute hypersensitivity or anaphylaxis.
Contraindications and cautions
- Hypersensitivity to glucarpidase or any excipient.
Monitoring
- Measure plasma methotrexate concentrations and renal function before and after treatment.
- Be alert to methotrexate rebound from tissue redistribution.
- DAMPA can interfere with routine methotrexate immunoassays; use an appropriate chromatographic method when an accurate early result is clinically important.
- Continue assessment for methotrexate toxicity and infusion-related or allergic reactions.
Clinical pharmacology
Glucarpidase is a recombinant bacterial carboxypeptidase that hydrolyses extracellular methotrexate to DAMPA and glutamate. Its large molecular size limits cellular entry, preserving methotrexate activity within cells.
Formulation and product differences
- UK-authorised Voraxaze is a refrigerated powder for intravenous injection that requires reconstitution with sterile sodium chloride immediately before use.
- It contains lactose, trometamol and zinc acetate dihydrate and must not be frozen or mixed with other medicines.
- No clinical data are available for infants younger than 28 days.
Glucarpidase interactions
The most clinically important interactions involve folate-related treatments used during methotrexate rescue.
Folinic acid (leucovorin)
Glucarpidase can break down folinic acid and reduce its rescue effect, so administration must be coordinated by the treating team.
Other folate analogues or folate-antagonist medicines
Glucarpidase may reduce their circulating concentrations; the oncology or pharmacy team should assess clinical relevance.
Sources
These sources were used to prepare and review this medicine page.
Prepared and reviewed by the iatroX editorial team.