zanubrutinib: clinical use

Prescribing considerations

• Initiate and supervise treatment through a clinician experienced in anticancer therapy.
• Assess bleeding risk, including concomitant anticoagulants, antiplatelets, supplements and planned invasive procedures.
• Establish hepatitis B status before treatment; seek liver-specialist input for positive serology.
• Assess infection risk and consider appropriate prophylaxis in higher-risk patients.
• Assess cardiac history and risk factors for atrial fibrillation or flutter.
• Review CYP3A and transporter interactions, hepatic impairment and severe renal impairment.
• Assess tumour-lysis risk, particularly with high tumour burden or raised urate.
• Advise sun protection because secondary skin cancers have occurred.

Contraindications and cautions

• Hypersensitivity to zanubrutinib or any product excipient.
• Avoid concomitant warfarin or another vitamin K antagonist as specified in the product information.

Monitoring

• Full blood count before and regularly during treatment.
• Signs of bleeding, infection and hepatitis B reactivation.
• Symptoms or signs of atrial fibrillation or flutter and blood pressure.
• Toxicity when interacting medicines are started or stopped.
• Renal function, liver function and tumour-lysis parameters when clinically indicated.
• Skin examination where clinically appropriate.

Clinical pharmacology

Zanubrutinib is an oral, covalent BTK inhibitor. It is primarily metabolised by CYP3A and can mildly induce CYP3A and CYP2C19; it can also affect P-glycoprotein substrates.

Formulation and product differences

• The selected product is a hard capsule for oral use.
• Capsules must be swallowed whole and should not be opened, broken or chewed.
• The capsule shell contains gelatin.

Capsule

Route: Oral

Strengths: 80 mg