Tucatinib
Tucatinib is an oral targeted therapy medication that specifically inhibits the HER2 tyrosine kinase, blocking signals that promote cancer cell growth and proliferation. It is primarily used to treat HER2-positive breast cancer, often in combination with other HER2-targeted agents for patients who have received prior therapy.
Tucatinib is a HER2-selective tyrosine kinase inhibitor used to treat HER2-positive cancers, particularly breast cancer.
Key facts at a glance
- ATC
- L01EH03
- RxNorm
- 2361285
- Generic
- Tucatinib
- Class
- atc-l01
- Brands
- Tukysa
- Availability
- rx
- Lactation
- unknown
- Routes
- oral
- Forms
- tablet
- Regions
- US, EU, CN, JP
- Monitoring
- —
This page is for informational purposes only.
Do not use this information to diagnose yourself or to replace a physician's advice. Always consult a qualified healthcare provider before starting, stopping, or changing any medication. If you believe you are experiencing a medical emergency, call your local emergency number immediately.
Tucatinib is indicated for the treatment of adult patients with advanced HER2-positive breast cancer, including those with brain metastases, typically used in combination with trastuzumab and capecitabine after prior treatment with anti-HER2-based therapy.
As a highly selective HER2 tyrosine kinase inhibitor, tucatinib blocks HER2 and HER3 phosphorylation, which inhibits downstream MAPK and AKT signaling pathways. This interference with these critical signaling cascades leads to reduced cell proliferation and anti-tumor activity in HER2-expressing cancer cells.
Tucatinib is administered orally as a tablet, typically twice daily. Common adverse effects may include diarrhea, hand-foot syndrome, nausea, fatigue, and liver enzyme elevations. Regular monitoring of liver function is recommended. Patients should be advised about potential drug interactions and the importance of adherence to the dosing schedule.
Official drug label
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This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed July 26, 2026. · Read our editorial policy