فورمستان

Also known as LTR323, CGP-32349, 4-hydroxy-Δ4-androstenedione, 4-hydroxy-4-androstene-3,17-dione, CGP 32349, Formestano, Formestanum, 4-hydroxyandrostenedione

Formestane, formerly sold under the brand name Lentaron among others, is a steroidal, selective aromatase inhibitor which is used in the treatment of estrogen receptor-positive breast cancer in postmenopausal women. The drug is not active orally, and was available only as an intramuscular depot injection. Formestane was not approved by the United States FDA and the injectable form that was used in Europe in the past has been withdrawn from the market. Formestane is an analogue of androstenedione.