BTK inhibitor (specialist) Pregnancy: Can cause fetal harm based on findings in animals. Women should be advised to avoid pregnancy while taking it and to use effective contraception; advise of the potential risk to a fetus.

Zanubrutinib

Brand names: Brukinsa

Zanubrutinib is a second-generation Bruton tyrosine kinase (BTK) inhibitor used in B-cell malignancies including Waldenstrom macroglobulinaemia, chronic lymphocytic leukaemia/small lymphocytic lymphoma, mantle cell lymphoma and marginal zone lymphoma.

Auto-extracted from the source labelling — not yet independently clinician-verified. These values were distilled from the UK SPC (or the US label where noted) but have not had a clinician sign-off. Confirm against the current SmPC before prescribing.

Adult dose

Dose: 160 mg orally twice daily OR 320 mg orally once daily

Route: Oral

Frequency: Twice daily (160 mg) or once daily (320 mg)

With or without food; swallow capsules whole with water (do not open, break or chew); tablets may be split in half as prescribed (do not chew or crush). For monotherapy or in combination with obinutuzumab, until disease progression or unacceptable toxicity. Severe hepatic impairment (Child-Pugh class C): 80 mg twice daily; no modification for mild or moderate impairment (Child-Pugh A or B). Dose modifications required with moderate/strong CYP3A inhibitors (reduce dose) and moderate CYP3A inducers (increase to 320 mg twice daily if unavoidable). Manage Grade 3 or higher toxicity by treatment interruption, dose reduction or discontinuation. Safety and effectiveness in paediatric patients have not been established. (US labelling - BRUKINSA.)

Dose auto-extracted from US FDA prescribing information (openFDA / DailyMed) — cross-check; US labelling may differ from UK — not yet clinician-verified. Always confirm against the product SmPC and your local formulary before prescribing.

Contraindications

None

Side effects

Neutrophil count decreased
Platelet count decreased
Upper respiratory tract infection
Haemorrhage/bleeding
Musculoskeletal pain

Interactions

Moderate and strong CYP3A inhibitors - increase zanubrutinib exposure; reduce zanubrutinib dose
Moderate and strong CYP3A inducers - decrease zanubrutinib exposure; avoid coadministration (if a moderate inducer cannot be avoided, increase dose to 320 mg twice daily)

Clinical monograph

How it works

It irreversibly inhibits BTK, a key signalling kinase in the B-cell receptor pathway, thereby blocking malignant B-cell proliferation and survival.

Prescribing in practice

Confers a risk of serious haemorrhage; assess bleeding risk and withhold around surgery, and use caution with anticoagulants and antiplatelets.
Can cause cytopenias, infections and atrial fibrillation/flutter, so cardiac and haematological status should be monitored.
Exposure is altered by CYP3A inhibitors and inducers, and dose adjustment may be required as directed by the SPC.

Monitoring

Monitor full blood count regularly and assess for signs of bleeding, infection, new arrhythmia and second primary malignancies (especially skin).

Counselling the patient

Report unusual bruising, bleeding, fever or signs of infection promptly.
Tell your team about any new palpitations or breathlessness.
Use sun protection and report new skin lesions.

Evidence & guidelines

Randomised trials (including ALPINE in chronic lymphocytic leukaemia and ASPEN in Waldenstrom macroglobulinaemia) support its efficacy, and it is recommended within its licensed indications.

Reference: NICE TA836 (CLL); NICE TA862 (WM); SmPC; Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. The structured dose values shown have been reviewed by a clinician. Monograph status: clinician-reviewed (2026-07-04).

Curated clinical cross-links plus same-class fallbacks.

Calculators

Pathways