Irving M. Spitz

PURPOSE OF REVIEW: In view of the spate of recent publications related to mifepristone and some second generation progesterone receptor modulators (PRMs), this appears to be an opportune time to view the clinical status of these compounds. …

Progesterone receptor antagonists (PAs) and selective progesterone receptor modulators (SPRMs) are members of the progesterone receptor ligand family. The PA mifepristone is usually used as a single dose for short-term indications, such as …

Since the discovery of the progesterone receptor antagonist mifepristone, numerous additional compounds, which display a spectrum of biological actions ranging from full antagonist to those with mixed agonist/antagonist activity, have been …

Since the discovery of the antiprogestin mifepristone, hundreds of similar compounds have been synthesized, which can be grouped in a large family of progesterone receptor ligands. This family includes pure agonists such as progesterone its…

BACKGROUND: Many techniques have been developed to soften the cervix to reduce complications following surgical dilatation. Progesterone inhibits myometrial contractility and its secretion during pregnancy ensures cervical competence. We us…

Since the discovery of the antiprogestin RU 486 (mifepristone), other compounds have been synthesised that function as pure progesterone antagonists or progesterone receptor modulators. The latter are mixed agonists-antagonists. Mifepriston…

Considerable progress has been made in elucidating the mechanism of action of antiprogestins. The biological response to a progesterone antagonist depends on many factors. The usual effect is that of an antagonist, but progesterone agnostic…

RU486, a 19-nor steroid, binds with high affinity to the receptors for progesterone and glucocorticoids, blocking the actions of these hormones on their target tissues. We conducted studies to determine whether RU486 administered at the end…