Neratinib is an oral tyrosine kinase inhibitor, which is mainly used for adjuvant treatment and advanced treatment of HER2 positive breast cancer. Special attention should be paid to diarrhea management, liver toxicity monitoring, and pregnancy risk prevention and control when using the medication. The following sub items describe the indications and core precautions.

1. Indications

(1) Early HER2 positive breast cancer: after completing adjuvant therapy with trastuzumab, it is used for intensive treatment to extend disease-free survival period.

(2) Metastatic HER2 positive breast cancer: combined with capecitabine to treat advanced patients who have received ≥ 2 anti HER2 regimens.

2. Medication precautions

(1) Diarrhea management

The incidence rate is as high as 90%, with a median occurrence time of 2 days after medication. Prophylactic use of loperamide is required, with continuous administration for 56 days prior to treatment and subsequent adjustments as needed. If diarrhea of grade ≥ 2 occurs, medication should be suspended until it returns to grade ≤ 1 and then reduced and restarted.

(2) Hepatotoxicity monitoring

May cause ALT/AST to rise to>5 times the upper limit of normal values. Check liver function every 3 weeks before medication and during treatment. If any abnormalities occur, discontinue medication or adjust dosage.

(3) Embryo fetal toxicity

Animal studies have shown teratogenic risks. Women of childbearing age need to confirm their pregnancy status before taking medication. During treatment and one month after the last dose, efficient contraceptive measures should be taken, and breastfeeding is prohibited.

(4) Other adverse reactions

Including nausea, abdominal pain, fatigue, etc. Symptomatic treatment, dosage adjustment, or suspension of medication should be taken according to the severity. Non hematological toxicity of grade 3 or above requires permanent discontinuation of medication.