Formulation and Specifications: Tablets: 50mg, 100mg, 150mg
Indications: Locally advanced or metastatic breast cancer that is HR-positive and HER2-negative: (1) Use in combination with an aromatase inhibitor as initial endocrine therapy in postmenopausal female patients. (2) In combination with fulvestrant for patients who have experienced disease progression after prior endocrine therapy.
Key points for rational drug use:
1. Patients with confirmed HR-positive and HER2-negative disease should be tested in a qualified pathology laboratory before receiving abexilide therapy.
2. Abecirib therapy should be initiated by a physician with experience in antineoplastic therapy and monitored during treatment. The recommended dose of abexilide in combination with endocrine therapy is 150 mg/dose twice daily. If a patient vomits or misses a dose of abexilide, the dose should not be made up and the next dose should be taken as scheduled. Abexilide may be administered on an empty stomach or with food. Abexilide should not be taken with grapefruit or grapefruit juice.
3. No dose adjustment is necessary for patients with mild (Child-Pugh class A) or moderate (Child-Pugh class B) hepatic impairment; patients with severe (Child-Pugh class C) hepatic impairment are advised to reduce the frequency of dosing to once daily.
4. Complete blood counts should be monitored prior to initiation of abecedrine therapy, every 2 weeks for the first 2 months of therapy, monthly for the next 2 months, and at the onset of clinical indications. Before starting treatment, it is recommended that absolute neutrophil counts should be ≥1.5×109/L, platelet counts should be ≥100×109/L and hemoglobin should be ≥80 g/L. Neutropenia is frequently reported, with a median time from treatment initiation to the onset of grade 3 or 4 neutropenia of 29 to 33 days and to The median time to remission is 11 to 15 days. For patients who develop grade 3 or 4 neutropenia, it is recommended that dosing be suspended until toxicity is reduced to grade 2 or less. Consider the need for dose reduction upon re-dosing.
5. A common adverse event is diarrhea, the incidence of which is highest during the first month of treatment and decreases thereafter. In various studies, the median time from treatment initiation to the first diarrheal event was 6 to 8 days, and the median duration of diarrhea was 9 to 12 days (Grade 2) and 6 to 8 days (Grade 3). Diarrhea may resolve to baseline or a lower grade with supportive therapy (e.g., loperamide) and/or dose adjustment. If diarrhea occurs, supportive measures should be taken as early as possible. These include the following: Patients should be started on antidiarrheal therapy at the first sign of loose stools. Encourage the patient to drink fluids (e.g., 8 to 10 glasses of plain water per day). If the diarrhea does not resolve to at least grade 1 within 24 hours after receiving antidiarrheal therapy, the medication should be withheld until the diarrhea resolves to at least grade 1.
6. Combined use of potent CYP3A4 inhibitors should be avoided. If potent CYP3A4 inhibitors cannot be avoided, the dose of abecedrine should be reduced to 100 mg/dose twice daily. If CYP3A4 inhibitor therapy is discontinued, the dose of abexilide should be raised to the dose used before starting CYP3A4 inhibitor therapy (after 3 to 5 half-lives of that CYP3A4 inhibitor).