Tucatinib/tucatinib mechanism of action

Tucatinib/Tucatinib is used along with the drugs trastuzumab and capecitabine in adult patients with HER2-positive breast cancer, including cancer that has spread to the brain. It is used in patients who have received one or more anti-HER2 breast cancer treatments that no longer respond. It is also indicated in combination with trastuzumab for the treatment of adult patients with RAS wild-type HER2-positive unresectable or metastatic colorectal cancer who have progressed after receiving fluoropyrimidine-, oxaliplatin-, and irinotecan-based chemotherapy. This method is used when the cancer has spread within the body (metastatic) or cannot be removed with surgery (unresectable).

People with HER2+ cancer have a gene that causes their cells to produce too much of the HER2 protein. Too much HER2 can cause cells to grow more aggressively. Tucatinib is a human epidermal growth factor receptor-2 (HER2) inhibitor that helps patients with advanced breast or colorectal cancer slow or stop the growth of cancer cells by blocking the HER2 protein. Some cancers overexpress the HER2 protein, causing cancer cells to grow and spread. Tucatinib is an oral targeted drug therapy that is highly selective for the HER2 protein and works within cells. Tucatinib binds to HER2's tyrosine kinase (an enzyme) and reduces PI3 kinase and MAP kinase signaling. The weakened signal helps prevent cell growth and leads to cell death. Tucatinib is classified as a HER2 tyrosine kinase inhibitor.

Tucatinib was approved by the U.S. Food and Drug Administration (FDA) in April 2020 and is produced by Seagen Company. It is an oral tablet that can be taken orally twice daily (12 hours apart), with or without food. Tucatinib must be used within 3 months after opening the vial. Throw away (throw away) any unused tablets after 3 months. Dosage adjustments may be needed ifthe patient has severe liver disease.