filgrastim: clinical use

Prescribing considerations

• Prescribe with an experienced oncology or haematology service and appropriate diagnostic support.
• Record the administered brand and batch number for biological-medicine traceability.
• Confirm the cause of neutropenia and account for marrow infiltration, infection or reduced myeloid reserve.
• Use caution with sickle-cell disease or trait, previous pulmonary infiltrates, osteoporosis and risk factors for splenic complications.
• Review sorbitol exposure and hereditary fructose intolerance; check the selected device for latex-related precautions.

Contraindications and cautions

• Hypersensitivity to filgrastim or a formulation excipient.
• Do not re-expose patients with clinically significant hypersensitivity to filgrastim or pegfilgrastim.
• Do not use for severe congenital neutropenia with leukaemia or evidence of leukaemic transformation.

Monitoring

• Full blood count with differential and platelets, tailored to the indication and treatment phase.
• Assess for splenomegaly or splenic rupture, pulmonary toxicity, capillary leak, hypersensitivity and sickle-cell crisis.
• Urinalysis if kidney inflammation is suspected or during relevant long-term treatment.
• Bone density may be appropriate during prolonged treatment in patients with underlying osteoporotic disease.
• For stem-cell mobilisation, monitor collection yield and donor blood counts until recovery.

Clinical pharmacology

Recombinant methionyl human G-CSF produced using recombinant DNA technology in E. coli. It stimulates neutrophil precursor proliferation, differentiation and release; circulating neutrophils retain normal or enhanced functional activity.

Formulation and product differences

• The selected Zarzio presentation is a biosimilar pre-filled syringe for subcutaneous injection or, after appropriate preparation, intravenous infusion; its needle-safety mechanism limits measurement of very small volumes.
• The selected Neupogen presentation is a pre-filled syringe supplied as a solution for injection or concentrate for infusion.
• Both selected products contain sorbitol and are essentially sodium-free.
• The Neupogen syringe needle cover may contain dry natural rubber derived from latex; check device components for patients with relevant allergy.
• Dilution, compatibility, storage excursions and syringe operation are product-specific; follow the exact product information and pack leaflet.

Injection

Route: Parenteral

Strengths: 0.3 mg/mL