Zanubrutinib is a chemotherapy drug used to treat certain types of B-cell non-Hodgkin lymphoma. These are blood cancers that affect B-lymphocytes, a, type of white blood cell that help you fight off infection. They occur when your body makes too many abnormal B-cells.

Zanubrutinib belongs to a class of drugs called kinase inhibitors. Zanubrutinib is a second-generation irreversible BTK (Bruton tyrosine kinase) inhibitor that works by blocking the action of a protein called Bruton's tyrosine kinase, which signals B-cells to grow and multiple. This stops cancer cells from multiplying in your body.

Zanubrutinib was approved by the US Food and Drug Administration (FDA) in 2019.

What is zanubrutinib used for?

Zanubrutinib is a prescription medicine used to treat adults with:

• Mantle cell lymphoma (MCL) who have received at least one prior treatment for their cancer.
• Waldenström's macroglobulinemia (WM).
• Marginal zone lymphoma (MZL) when the disease has come back or did not respond to treatment and who have received at least one certain type of treatment.

It is not known if zanubrutinib is safe and effective in children.

• Take zanubrutinib exactly as your healthcare provider tells you to take it.
• Do not change your dose or stop taking zanubrutinib unless your healthcare provider tells you to.
• Your healthcare provider may tell you to decrease your dose, temporarily stop, or completely stop taking zanubrutinib if you develop certain side effects.
• Take zanubrutinib with or without food.
• Swallow zanubrutinib capsules whole with a glass of water. Do not open, break, or chew the capsules.

• The recommended dose of zanubrutinib is 160 mg orally twice daily or 320 mg orally once daily; swallow whole with water and with or without food.
• Do not to open, break, or chew capsules.
• In patients with severe hepatic impairment the dose of zanubrutinib should be reduced.
• See full prescribing information for further details about zanubrutinib dosing.

Before taking zanubrutinib, tell your healthcare provider about all of your medical conditions, including if you:

• have bleeding problems.
• have had recent surgery or plan to have surgery. Your healthcare provider may stop zanubrutinib for any planned medical, surgical, or dental procedure.
• have an infection.
• have or had heart rhythm problems.
• have high blood pressure.
• have liver problems, including a history of hepatitis B virus (HBV) infection.

If you miss a dose of zanubrutinib, take it as soon as you remember on the same day. Return to your normal schedule the next day.

Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom).

It is important to keep all medication out of sight and reach of children as many containers (such as weekly pill minders and those for eye drops, creams, patches, and inhalers) are not child-resistant and young children can open them easily. To protect young children from poisoning, always lock safety caps and immediately place the medication in a safe location – one that is up and away and out of their sight and reach. http://www.upandaway.org

Unneeded medications should be disposed of in special ways to ensure that pets, children, and other people cannot consume them. However, you should not flush this medication down the toilet. Instead, the best way to dispose of your medication is through a medicine take-back program. Talk to your pharmacist or contact your local garbage/recycling department to learn about take-back programs in your community. See the FDA's Safe Disposal of Medicines website (http://goo.gl/c4Rm4p) for more information if you do not have access to a take-back program.

Talk to your doctor about eating grapefruit and drinking grapefruit juice while taking this medication.

Zanubrutinib may cause serious side effects, including:

• Bleeding problems (hemorrhage) that can be serious and may lead to death. Your risk of bleeding may increase if you are also taking a blood thinner medicine. Tell your healthcare provider if you have any signs or symptoms of bleeding, including:
  • blood in your stools or black stools (looks like tar)
  • pink or brown urine
  • unexpected bleeding, or bleeding that is severe or you cannot control
  • vomit blood or vomit that looks like coffee grounds
  • cough up blood or blood clots
  • increased bruising
  • dizziness
  • weakness
  • confusion
  • change in speech
  • headache that lasts a long time
• Infections that can be serious and may lead to death. Tell your healthcare provider right away if you have fever, chills, or flu-like symptoms.
• Decrease in blood cell counts. Decreased blood counts (white blood cells, platelets, and red blood cells) are common with zanubrutinib, but can also be severe. Your healthcare provider should do blood tests during treatment with zanubrutinib to check your blood counts.
• Second primary cancers. New cancers have happened in people during treatment with zanubrutinib, including cancers of the skin or other organs. Your healthcare provider will check you for other cancers during treatment with zanubrutinib. Use sun protection when you are outside in sunlight.
• Heart rhythm problems (atrial fibrillation and atrial flutter). Tell your healthcare provider if you have any of the following signs or symptoms:
  • your heartbeat is fast or irregular
  • feel lightheaded or dizzy
  • pass out (faint)
  • shortness of breath
  • chest discomfort

The most common side effects of zanubrutinib include:

• decreased white blood cells
• upper respiratory tract infection
• decreased platelet count
• bleeding
• rash
• muscle or joint pain

These are not all the possible side effects of zanubrutinib.

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Tell your healthcare provider about all the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements. Taking zanubrutinib with certain other medications may affect how zanubrutinib works and can cause side effects.

Keep all appointments with your doctor and the laboratory. Your doctor may order certain lab tests to check your body's response to zanubrutinib.

Do not let anyone else take your medication. Ask your pharmacist any questions you have about refilling your prescription.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.