Formulation and Specifications: Tablets: 40 mg
Indications: Indicated for intensive adjuvant therapy in adult patients with HER2-positive early-stage breast cancer after adjuvant trastuzumab-containing therapy.
Key points for rational use:
1. HER2 testing is required for patients considering this drug, and only HER2-positive patients should be treated with neratinib.
2. The recommended dose of neratinib is 240 mg once daily with meals for one year. Patients are instructed to take neratinib at approximately the same time each day and to swallow neratinib whole (tablets should not be chewed, crushed or split before swallowing). If a patient misses a dose, the missed dose should not be made up and the patient should be instructed to take neratinib again the next day at the daily dose.
3. The main adverse reaction is diarrhea. The incidence and severity of diarrhea may be reduced by prophylactic use of antidiarrheal medication, dietary changes, and appropriate adjustment of the neratinib dose. Patients were instructed to start prophylactic administration of the antidiarrheal drug loperamide at the time of the first dose of neratinib and to continue for 2 cycles (56 days). The prophylactic dosing regimen for loperamide is shown in the following table.
Table 7 Prophylactic Dosing Regimen for Loperamide
Diarrhea may be controlled by temporarily interrupting neratinib administration or reducing its dose as clinically indicated, with the lowest neratinib dose taken being 120 mg/d.
The starting dose of neratinib in patients with severe hepatic impairment is reduced to 80 mg. For patients with mild to moderate hepatic impairment, no dose adjustment is recommended.
5. Drug interactions: (1) Proton pump inhibitors (PPI): Avoid coadministration with neratinib. (2) H2receptor antagonists: Administer neratinib at least 2 hours before or 10 hours after the next dose of H2receptor antagonists. (3) Antacids: Neratinib should not be given until 3 hours after antacid administration. (4) Avoid concomitant administration of neratinib with potent or moderate CYP3A4 inducers.
6. Clinical studies have shown that neratinib in combination with capecitabine may provide clinical benefit in the treatment of advanced or metastatic breast cancer.