Ibrutix

Indications

Ibrutinib is a targeted cancer medicine taken by mouth. It is used to treat certain blood cancers of B cells (a type of white blood cell), including chronic lymphocytic leukaemia (CLL), small lymphocytic lymphoma, mantle cell lymphoma and Waldenstrom's macroglobulinaemia. It is also used for chronic graft versus host disease after a stem cell transplant. It is prescribed and monitored by a cancer or blood specialist.

How It Works

Ibrutinib blocks an enzyme called Bruton's tyrosine kinase (BTK). Cancerous B cells depend on signals passed through BTK to grow, survive and stay in the lymph nodes and bone marrow. Blocking BTK slows the growth of these cells and helps them die off.

Dosage and Administration

The dose depends on the condition being treated and is set by your specialist; take exactly as prescribed. It is taken once a day at about the same time, swallowed whole with a glass of water. Do not open, break or chew capsules or tablets. Do not take it with grapefruit or Seville oranges. Doses may be reduced if side effects occur or if you take certain other medicines.

Interactions

Many medicines change Ibrutinib levels. Strong enzyme blockers such as Ketoconazole, Itraconazole, Voriconazole, Clarithromycin and Ritonavir can raise levels and increase side effects. Enzyme inducers such as Rifampicin, Carbamazepine, Phenytoin and St John's Wort can lower its effect. Blood thinners such as Warfarin, Aspirin, Clopidogrel and other antiplatelet medicines increase the risk of bleeding. Always tell your doctor and pharmacist about every medicine and supplement you take.

Contraindications

Do not take if you are allergic to Ibrutinib, or if you are taking St John's Wort. Not suitable for people with severe liver impairment unless the specialist decides otherwise.

Side Effects

• Diarrhoea, nausea and mouth sores
• Bruising and minor bleeding
• Muscle, bone and joint pain, muscle cramps
• Rash and tiredness
• Infections such as chest infections
• High blood pressure
• Low blood counts (low platelets, white cells or red cells)

Get urgent medical help if you have serious bleeding (blood in vomit, stool or urine, a severe headache or confusion), signs of infection such as fever and chills, a fast or irregular heartbeat, chest pain, fainting, shortness of breath, or sudden weakness.

Pregnancy and Lactation

Ibrutinib may harm an unborn baby and must not be used in pregnancy. Women who can become pregnant should use highly effective contraception during treatment and for at least 3 months after the last dose. Do not breastfeed while taking it.

Precautions and Warnings

Your doctor will check your blood counts, heart rhythm and blood pressure regularly. Tell your doctor before any surgery or dental work, as treatment may need to be stopped for a few days to reduce bleeding risk. Tell your doctor if you have heart disease, liver disease, kidney disease, hepatitis B infection, or a bleeding problem. Drink plenty of fluids, as Ibrutinib can cause tumour lysis syndrome (a chemical imbalance when many cancer cells break down).

Overdose

Taking too much may increase the risk of bleeding and other serious side effects. Contact your doctor or go to hospital immediately.

Therapeutic Class

Antineoplastic (anticancer) medicine, Bruton's tyrosine kinase (BTK) inhibitor.

Storage

Store below 30°C in a dry place, in the original pack, away from light and out of the reach of children. Return unused medicine to a pharmacy for safe disposal.