Population pharmacokinetics of telapristone (CDB-4124) and its active monodemethylated metabolite CDB-4453, with a mixture model for total clearance.

Telapristone is a selective progesterone antagonist that is being developed for the long-term treatment of symptoms associated with endometriosis and uterine fibroids. The population pharmacokinetics of telapristone (CDB-4124) and CDB-4453 was investigated using nonlinear mixed-effects modeling. Data from two clinical studies (n = 32) were included in the analysis.

Lack of correlation of vaginal impedance measurements with hormone levels in the rat.

Hormone levels vary in female rats depending on estrous cycle stage. Vaginal cytology is a reliable method of staging female rats, but vaginal impedance offers an alternative depending on application. We sought to correlate vaginal impedance in cycling female rats with hormone levels.