Tucatinib/tucatinib administration method and dose adjustment

According to the latest clinical treatment recommendations, patients should take Tucatinib/Tucatinib in two divided doses per day, with a dose of 300 mg each time. This medication pattern should be continued until the disease progresses or the side effects of the drug become unacceptable. When tucatinib is used in combination with trastuzumab and capecitabine, the recommended dose of capecitabine is 1000 mg/m² of body surface area twice daily within 30 minutes of a meal. All medication should strictly follow the doctor's instructions and relevant clinical treatment specifications.

When taking tucatinib, patients should swallow the tablets whole and avoid chewing, crushing or splitting the tablets. Tablets should not be taken if they are damaged, cracked or incomplete. The time interval between two doses should be approximately 12 hours, and the time of taking the medication is not directly related to meal times. If the patient vomits or misses a dose, the next dose can be taken at the scheduled time.

Based on the patient's adverse reactions, doctors may adjust the dose of tucatinib. The first adjustment can be reduced to 250 mg twice a day. If further adjustment is needed, it can be reduced to 200 mg twice a day. The final adjustment can be reduced to 150 mg twice a day. For those patients who cannot tolerate the 150 mg dose, the drug should be permanently discontinued. If the patient has severe liver impairment, the dose should be reduced to 200 mg twice daily. In addition, patients should avoid concurrent use with strong CYP2C8 inhibitors. If this combination cannot be avoided, the tucatinib dose should be reduced to 100 mg twice daily. When an inhibitor is discontinued, the previous dose should be restored.