testolactone

Testolactone is a synthetic antineoplastic agent and a derivative of progesterone used primarily to treat advanced breast cancer in women. It acts as a non-selective, irreversible steroidal aromatase inhibitor, blocking the conversion of adrenal androgens (mainly androstenedione) to estrogens by inhibiting the aromatase enzyme. This leads to reduced estrogen synthesis, which is particularly important in postmenopausal women where peripheral conversion is the main source of estrogen. The inhibition may be noncompetitive and irreversible, resulting in persistent suppression of estrogen even after drug withdrawal. Testolactone has also been reported to possess weak androgenic activity but with very low affinity for the androgen receptor[2][5][6][7].

Brand names

Teslac

Other names

13-hydroxy-3-oxo-13,17-secoandrosta-1,4-dien-17-oic acid δ-lactone