Mifepristone: pharmacology and clinical impact in reproductive medicine, endocrinology and oncology.

IMPORTANCE OF THE FIELD: Mifepristone is a synthetic selective progesterone-receptor modulator (SPRM) that is widely used around the globe in the field of reproductive medicine. At present mifepristone is approved in a number of countries for early termination of pregnancy (TOP), cervical dilatation before surgical TOP, and management of early embryonic loss or fetal death. A number of new clinical applications are being developed in gynecology, endocrinology and oncology. Mifepristone has also served as an invaluable tool in the study of steroid hormone biology. AREAS COVERED IN THIS REVIEW: Current indications for mifepristone are reviewed. New applications for mifepristone under clinical investigation are discussed. In addition, the unique molecular and cellular effects of mifepristone are described. WHAT THE READER WILL GAIN: The reader will understand the mechanisms of action of mifepristone and the underlying steroid hormone biology. The reader will know the approved clinical indications for mifepristone and appreciate the ongoing basic and clinical research into new applications. TAKE HOME MESSAGE: Mifepristone is the first-discovered and still most widely used antiprogestin. It has several indications in reproductive medicine and is under investigation for a variety of potential applications in other fields of medicine. The molecular and cellular effects of mifepristone illuminate important aspects of steroid hormone biology.