Bioavailability File: Exemestane
Burçin YAVUZ*,^o, Erem BİLENSOY*, Murat ŞUMNU*
*Hacettepe University, Faculty of Pharmacy, Department of Pharmaceutical Technology, Sıhhiye Ankara- Turkey

^oCorresponding Author

Summary

Exemestane (EXE) is an irreversible aromatase inactivator used for the treatment of postmenopausal women with advanced breast cancer. It is effective in postmenopausal patients with tamoxifen-refractory advanced breast cancer, prolonging time to disease progression and treatment failure and improving survival. The mean plasma elimination half-life of EXE is 24 hours. EXE binds covalently to the active site cytochrome P450, inactivates aromatase and reduces plasma estrogen level. EXE is metabolized in the liver, and cytochrome P450 3A4 (CYP 3A4) is the principal isoenzyme involved in the oxidation of this drug. EXE has been developed for oral administration and is marketed as Aromasin® tablets. In this review, the physicochemical, pharmacological and pharmacokinetic properties and bioavailability of EXE are discussed.
 
Key Words :
Exemestane, bioavailability, pharmacokinetics, breast cancer, aromatase inhibitor.