About Formestane

Formestane (Lentaron) is a type I, steroidal aromatase inhibitor. It is used in the treatment of estrogen-receptor positive breast cancer in post-menopausal women. It is available as an intramuscular depot injection.
Formestane is often used to suppress estrogen production from anabolic steroids or prohormones. It also acts as a prohormone to 4-hydroxytestosterone, an active steroid which displays weak androgenic activity in addition to acting as a mild aromatase inhibitor.
Formestane has poor oral bioavailability and as such is no longer popular as many orally active aromatase inhibitors have been identified.

Catalog No: 3B3-004639
CAS No: 566-48-3
Molecular Formula: C19H26O3
Molecular Weight: 302.41