Bosutinib
Kinase inhibitors (targeted oncology)
Kinase inhibitors (targeted oncology)High alert
An error with this medicine can cause serious harm: double checks and protocols are used.
Second-generation BCR-ABL and SRC kinase inhibitor taken by mouth for Ph-positive CML. Diarrhoea is its hallmark; it does not work against T315I.
Quick facts
- Group
- Kinase inhibitors (targeted oncology)
- Target
- BCR-ABL tyrosine kinase (ABL1 kinase domain); also SRC-family kinases
- Key effects
- Diarrhoea · Rash · Tiredness
- Monitor
- Liver enzymes monthly at first · Blood count · Weight
- ATC
- L01EA04
No doses: the clinician sets them by the current guideline.
Mechanism of action
The crystal shows bosutinib in the ATP pocket of the human ABL1 kinase domain.
Bosutinib competes with ATP in the kinase domain of BCR-ABL, the fusion protein made by the Philadelphia chromosome that drives chronic myeloid leukaemia. Blocking it stops the signals that make the leukaemic cells multiply and survive. It also inhibits SRC-family kinases (SRC, LYN, HCK). It inhibits most imatinib-resistant forms of BCR-ABL, but not the T315I and V299L mutants.
- Bosutinib takes ATP's place in the BCR-ABL kinase
- Growth and survival signals of the leukaemic clone stop
- Works on most imatinib-resistant mutants, not on T315I
Indications
- Chronic-phase Philadelphia chromosome-positive chronic myeloid leukaemia, newly diagnosed or resistant or intolerant to earlier therapy. Chronic myeloid leukaemia →
- Accelerated or blast phase Ph-positive chronic myeloid leukaemia after resistance or intolerance to earlier therapy. Chronic myeloid leukaemia →
Adverse effects
Common
- Diarrhoea (very common, usually early), nausea, vomiting, abdominal pain
- Rash
- Tiredness, headache, fever
- Respiratory infections
- Raised liver enzymes and creatinine
Contraindications
- Allergy to bosutinib
Key interactions
- Strong and moderate CYP3A inhibitors (e.g., ketoconazole, grapefruit)
- Raise bosutinib levels and toxicity; avoided.
- Strong CYP3A inducers (e.g., rifampicin, St John's wort)
- Lower bosutinib levels; avoided.
- Proton pump inhibitors
- Reduce absorption; short-acting antacids or H2 blockers are used instead.
What is monitored
- Liver enzymes monthly at first and then as needed
- Blood count
- Kidney function at baseline and during treatment
- Weight, oedema and breathlessness (fluid retention)
Administration and safety
- Oral tablet taken once a day with food.
- Swallowed whole: not cut, crushed, broken or chewed.
- Hazardous drug: tablets are handled with care.
Pregnancy and breastfeeding
Can cause fetal harm; effective contraception is used and breastfeeding is not advised.
Nursing care
- Plan for diarrhoea from the start: fluids and antidiarrhoeal medicine as ordered; report severe diarrhoea.
- Review all medicines for CYP3A inhibitors, inducers and proton pump inhibitors; avoid grapefruit.
- Weigh the patient and ask about swelling or breathlessness.
- Teach to report yellow skin, bruising, bleeding or fever.
Pharmacokinetics
- Absorption
- Oral tablet taken with food; acid suppression with proton pump inhibitors lowers absorption.
- Metabolism
- Liver, by CYP3A4.
- Half-life
- About 22 hours.
Test yourself
Think of the answer, then tap the question to see it.
Which BCR-ABL mutation is not inhibited by bosutinib?
T315I (and also V299L).
What is the most common adverse effect of bosutinib?
Diarrhoea, usually early in treatment.
Which acid-reducing drugs should be avoided with bosutinib, and what can be used instead?
Proton pump inhibitors; short-acting antacids or H2 blockers are used instead.
Connections
← Back to the class: Kinase inhibitors (targeted oncology)
Educational content on how drugs work; not a prescribing guide and no substitute for a health professional's advice. No doses are given.
Sources: DailyMed - BOSUTINIB tablet, film coated (DailyMed (U.S. National Library of Medicine), 2026); Bosutinib: MedlinePlus Drug Information (MedlinePlus (U.S. National Library of Medicine), 2021); Structural and spectroscopic analysis of the kinase inhibitor bosutinib binding to the Abl tyrosine kinase domain (RCSB Protein Data Bank, 2012).
Spotted a mistake?We are always improving for the community. Tell us what is wrong and our team will review it.Report a mistake
Representative model, for educational purposes only.