Zanubrutinib

How it works

It covalently binds and irreversibly inhibits Bruton tyrosine kinase, blocking B-cell receptor signalling needed for malignant B-cell proliferation and survival.

Prescribing in practice

• Serious bleeding and haemorrhage can occur, so use caution with antiplatelet or anticoagulant therapy and consider withholding around surgery.
• Cardiac arrhythmias including atrial fibrillation, cytopenias, infections and second primary malignancies are recognised risks requiring vigilance.
• It is metabolised by CYP3A, so doses may need adjustment with strong CYP3A inhibitors or inducers.

Monitoring

Monitor the full blood count, for bleeding, infection and new arrhythmia such as atrial fibrillation, and review concomitant CYP3A-interacting drugs.

Counselling the patient

• Report unusual bruising or bleeding, palpitations, fever or signs of infection.
• Tell the team before any planned surgery or dental procedure.
• Avoid grapefruit and check with the team before starting new medicines.

Evidence & guidelines

Zanubrutinib has demonstrated efficacy in chronic lymphocytic leukaemia and Waldenstrom macroglobulinaemia and is recommended by NICE for relevant indications.