bortezomib mannitol boronic ester: clinical use

Prescribing considerations

• Initiate under specialist oncology or haematology supervision; review information for every combination component.
• Assess neuropathy, blood counts, liver function, renal status, cardiovascular disease, postural symptoms, hydration and infection risk.
• Consider antiviral prophylaxis against herpes-zoster reactivation.
• Screen and monitor for hepatitis B when rituximab is included.
• Moderate or severe hepatic impairment requires product-specific adjustment; dialysis can affect concentrations.
• Use cytotoxic handling precautions; pregnant staff should not handle the product.

Contraindications and cautions

• Hypersensitivity to bortezomib, boron or a listed excipient.
• Acute diffuse infiltrative pulmonary disease.
• Pericardial disease.
• Apply contraindications belonging to combination partners.
• Intrathecal administration is prohibited and has caused deaths.

Monitoring

• Full blood count with differential and platelets.
• New or worsening sensory, motor or autonomic neuropathy.
• Infection, shingles and, where relevant, hepatitis B reactivation.
• Blood pressure, hydration, syncope and autonomic symptoms.
• Liver function and clinical renal status.
• Cardiac or pulmonary symptoms, tumour lysis syndrome and new neurological or visual symptoms.
• Blood glucose in people taking oral antidiabetic medicines.

Clinical pharmacology

Bortezomib reversibly inhibits the chymotrypsin-like activity of the 26S proteasome. It is extensively distributed, highly protein-bound and primarily oxidatively metabolised through CYP3A4, CYP2C19 and CYP1A2; deboronated metabolites are inactive as proteasome inhibitors.

Formulation and product differences

• The powder presentation requires reconstitution by a healthcare professional before intravenous or subcutaneous administration.
• The solution presentation is ready for subcutaneous use but requires dilution before intravenous use.
• Preparation requirements and final concentrations differ by route; route-specific checking and clear labelling are essential.
• Post-treatment contraception periods differ between the selected products, so instructions must match the prescribed product.

Injection

Route: Parenteral

Strengths: 1 mg, 2.5 mg, 2.5 mg/mL, 3.5 mg