Toripristone
Toripristone
Chemical compound
Toripristone (INN; developmental code name RU-40555) is a synthetic, steroidal antiglucocorticoid as well as antiprogestogen which was never marketed.[1][2] It is reported as a potent and highly selective antagonist of the glucocorticoid receptor (GR) (Ki = 2.4 nM),[3][4] though it also acts as an antagonist of the progesterone receptor (PR).[5][6] The pharmacological profile of toripristone is said to be very similar to that of mifepristone, except that toripristone does not bind to orosomucoid (α1-acid glycoprotein).[5] The drug has been used to study the hypothalamic-pituitary-adrenal axis and has been used as a radiotracer for the GR.[4][3] Its INN was given in 1990.[2]