Fulvenat® is a specialized oncology medication containing Fulvestrant (250 mg/vial), manufactured by NATCO Pharma. Functioning as a pure estrogen receptor antagonist (SERD), it works by binding irreversibly to estrogen receptors to accelerate their degradation and downregulate tumor growth signals. It is primarily indicated for treating hormone receptor-positive metastatic breast cancer in postmenopausal women experiencing disease progression after anti-estrogen therapy. Administered as a targeted intramuscular injection, Fulvenat® helps overcome traditional hormone therapy resistance mechanisms, offering a critical and degradation-focused therapeutic solution to achieve sustained anti-tumor activity.