How it is administered

Bosutinib is taken by mouth (orally) once daily with food. It is available as tablets in strengths of 100 mg, 400 mg, and 500 mg, and as capsules in 50 mg and 100 mg strengths. Tablets should be swallowed whole and not cut, crushed, or chewed. Capsules can be swallowed whole or, if swallowing is difficult, opened and mixed with applesauce or yogurt and taken immediately.

How it works

Bosutinib is a type of medicine called a tyrosine kinase inhibitor (TKI). It works by blocking the activity of a specific abnormal protein called BCR-ABL kinase, which is produced by the Philadelphia chromosome in chronic myeloid leukemia (CML). This abnormal protein causes white blood cells to grow uncontrollably. By blocking BCR-ABL and other related proteins, bosutinib helps slow down or stop the growth of leukemia cells.

Bosutinib is effective against many forms of BCR-ABL, including those that are resistant to some other TKIs, though it does not work against all mutations (for example, it does not inhibit the T315I and V299L mutations). By targeting these proteins, bosutinib helps restore normal blood cell production and control the progression of CML.

Who Should take it

Bosutinib is used in adults and children (1 year and older) with chronic phase Philadelphia chromosome-positive chronic myelogenous leukemia (Ph+ CML). It is prescribed for patients who are newly diagnosed or those who have not responded to, or cannot tolerate, previous treatments such as other TKIs.

It is also indicated for adults with more advanced forms of CML (accelerated or blast phase) who are resistant or intolerant to prior therapy. The decision to use bosutinib depends on your specific type of CML, previous treatments, and your overall health.

Who should not take it

You should not take bosutinib if you have had a severe allergic reaction (hypersensitivity) to bosutinib in the past. Symptoms of a severe reaction can include rash, swelling, difficulty breathing, or anaphylaxis.

Bosutinib is not recommended during pregnancy, as it can harm an unborn baby. Women who are pregnant or may become pregnant should discuss effective contraception with their healthcare provider. If you have severe liver or kidney problems, your doctor may adjust your dose or recommend a different treatment. Always inform your doctor about your full medical history before starting bosutinib.

Commonly used with

Bosutinib is usually used alone as a single agent for the treatment of CML. It is not typically combined with other chemotherapy drugs for CML, but your doctor may recommend supportive medications to help manage side effects, such as anti-diarrheal medicines, anti-nausea medicines, or medications to support blood counts if needed.

Commonly tested with

Bosutinib has been compared in studies with other TKIs such as imatinib, especially in newly diagnosed patients. In patients who are resistant or intolerant to other TKIs (like imatinib, dasatinib, or nilotinib), bosutinib may be tested as an alternative. Your doctor may also monitor your response to bosutinib with regular blood tests and molecular tests (such as BCR-ABL transcript levels) to check how well the medication is working.