ANZAKAST Tablets ANZAKAST contains Anastrozole, a potent and selective non-steroidal aromatase inhibitor. Anastrozole works by reversibly binding to the aromatase enzyme complex (cytochrome P450 unit), suppressing the conversion of adrenal androstenedione to estrone and subsequently to estradiol in peripheral tissues. By significantly lowering circulating serum estrogen concentrations without affecting adrenal corticosteroid or aldosterone synthesis, anastrozole deprives hormone-receptor-positive breast cancer cells of the estrogen stimulation required for tumor proliferation and survival. ANZAKAST is indicated for the adjuvant treatment of postmenopausal women with hormone-receptor-positive early breast cancer, as well as first-line or second-line treatment of postmenopausal women with advanced or metastatic breast cancer.