RU486: pharmacology and potential use in the treatment of endometriosis and leiomyomata uteri.

More than a decade after the serendipidous discovery of RU486, numerous antiprogestins have been synthesized and studied. Interest in how antiprogestins exert their antagonist effect has led to novel information about the molecular mechanisms of progesterone action. The pivotal role that progesterone plays in reproductive biology has led to research in many areas where a potential role for these compounds may be found in health and disease. RU486 has been shown to relieve pelvic pain associated with endometriosis and to decrease American Fertility Society endometriosis scores. Uterine leiomyomata show a significant reduction in size after administration of RU486 for 3 months. Although much research remains to be carried out, RU486 appears promising as alternative therapies for these diseases.