Fulvestrant Antiestrogen for Treatment of Breast Cancer

Fulvestrant injection (Faslodex®, AstraZeneca Pharmaceuticals LP, Wilmington, DE) is a novel estrogen receptor antagonist with no known agonist effects. Indicated for the palliative treatment of postmenopausal, endocrine-response, advanced breast cancer, the drug is well tolerated, and its most common side effect is mild gastrointestinal symptoms. Fulvestrant is administered as a once-a-month intramuscular injection in an outpatient setting. Its unique mechanism of action represents a new way to palliate breast cancer and may offer new options for women with advanced, endocrine-responsive disease.