Tucatinib/Tucatinib side effects

Tucatinib is a kinase inhibitor widely used in combination with trastuzumab and capecitabine to treat adult patients with advanced unresectable or metastatic HER2-positive breast cancer, including those with brain metastases. These patients had previously received one or more anti-HER2-based treatment regimens. Tucatinib is also used to treat RAS wild-type HER2-positive unresectable or metastatic colorectal cancer that has progressed after chemotherapy with fluoropyrimidine, oxaliplatin, and irinotecan.

However, there are some common side effects that may occur with tucatinib. Nearly all patients receiving the combination of trastuzumab and capecitabine may experience these side effects, with at least 20% requiring dose adjustments or treatment interruptions and 6% requiring permanent discontinuation. These common side effects include diarrhea, palmoplantar red blood cell paresthesia (hand-foot syndrome), nausea and vomiting, abdominal pain, fatigue, myalgia, arthralgia, cough, dyspnea, fever, lymphopenia, anemia, and elevated transaminases. Although uncommon, some serious adverse events may occur, such as severe diarrhea, hepatotoxicity, and embryo-fetal toxicity. It is important to note that some toxicities associated with the use of tucatinib may be due to the concomitant use of trastuzumab and capecitabine.

As a new drug for the treatment of breast cancer and colorectal cancer, tucatinib has played a positive role in improving patient prognosis. However, during the use of drugs, both doctors and patients need to pay close attention to possible side effects and take appropriate measures in a timely manner to alleviate these discomforts.