The termination of pregnancy results. During pregnancy, the compound sensitizes the myometrium to the contraction-inducing activity of prostaglandins.
Mifepristone also exhibits antiglucocorticoid and weak antiandrogenic activity.
Binding to the latter protein is saturable, and the drug displays nonlinear kinetics with respect to plasma concentration and clearance. In vitro studies have shown that CYP450 3A4 is primarily responsible for the metabolism. Serum levels are undetectable by 11 days. The effects of age, hepatic disease and renal disease on the safety, efficacy and pharmacokinetics of mifepristone have not been investigated. In the two French clinical trials, safety evaluable data are available for 1800 women, while efficacy information is available for 1681 of these women.