Class:
- Aromatase inhibitor (irreversible steroidal inhibitor)
Mechanism of Action:
- Blocks the aromatase enzyme, which converts androgens to estrogens in peripheral tissues.
- Reduces circulating estrogen levels, decreasing estrogen-driven tumor growth in hormone receptor-positive breast cancer.
Indications:
- Adjuvant treatment of hormone receptor-positive breast cancer in postmenopausal women.
- Treatment of advanced or metastatic breast cancer in postmenopausal women.
- Often used after 2–3 years of tamoxifen therapy or as initial endocrine therapy.
Dosing:
- Oral, 25 mg once daily.
Common Adverse Effects:
- Hot flashes
- Arthralgia/myalgia
- Osteoporosis and increased fracture risk
- Fatigue
- Nausea
Pharmacist Considerations:
- Counsel on bone health monitoring and calcium/vitamin D supplementation.
- Educate patients on managing menopausal symptoms.
- Monitor for drug interactions (exemestane is metabolized via CYP3A4).
- Emphasize adherence to daily oral therapy.