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Formestane

Generic Name
Formestane
Drug Type
Small Molecule
Chemical Formula
C19H26O3
CAS Number
566-48-3
Unique Ingredient Identifier
PUB9T8T355

Overview

Formestane was the first selective, type I, steroidal aromatase inhibitor used in the treatment of estrogen-receptor positive breast cancer in post-menopausal women. Formestane suppresses estrogen production from anabolic steroids or prohormones. Formestane is also a prohormone of 4-hydroxytestosterone, an active steroid with weak androgenic activity and mild aromatase inhibitor activity. It is listed as a prohibited substance by the World Anti-Doping Agency for use in athletes. Formestane has poor oral bioavailability, and thus must be administered fortnightly (bi-weekly) by intramuscular injection. Some clinical data has suggested that the clinically recommended dose of 250mg was too low. With the discovery of newer, non-steroidal and steroidal, aromatase inhibitors which were orally active and less expensive than formestane, formestane lost popularity. Currently, formestane (categorized as an anti-estrogenic agent) is prohibited from use in sports in accordance to the regulations of the World Anti-Doping Agency. It is not US FDA approved, and the intramuscular injection form of formestane (Lentaron) which was approved in Europe has been withdrawn.

Background

Formestane was the first selective, type I, steroidal aromatase inhibitor used in the treatment of estrogen-receptor positive breast cancer in post-menopausal women. Formestane suppresses estrogen production from anabolic steroids or prohormones. Formestane is also a prohormone of 4-hydroxytestosterone, an active steroid with weak androgenic activity and mild aromatase inhibitor activity. It is listed as a prohibited substance by the World Anti-Doping Agency for use in athletes. Formestane has poor oral bioavailability, and thus must be administered fortnightly (bi-weekly) by intramuscular injection. Some clinical data has suggested that the clinically recommended dose of 250mg was too low. With the discovery of newer, non-steroidal and steroidal, aromatase inhibitors which were orally active and less expensive than formestane, formestane lost popularity. Currently, formestane (categorized as an anti-estrogenic agent) is prohibited from use in sports in accordance to the regulations of the World Anti-Doping Agency. It is not US FDA approved, and the intramuscular injection form of formestane (Lentaron) which was approved in Europe has been withdrawn.

Indication

For the treatment of estrogen-receptor positive breast cancer in post-menopausal women.

Associated Conditions

No associated conditions information available.

FDA Approved Products

No FDA products found for this drug

Singapore Approved Products

No Singapore products found for this drug

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