Dienogest

A synthetic progestin and PR agonist (EC50s = 3.4-10.5 nM in transactivation assays); selective for PR over ERα and ERβ, as well as glucocorticoid, and mineralocorticoid receptors (EC50s = >3,000 nM for all), as well as SHBG and CBG (IC50s = 900-950 and 7,970 nM, respectively, in radioligand binding assays); inhibits dihydrotestosterone-induced transactivation of the androgen receptor (EC50s = 420.6-775 nM); reduces lesion formation in a rat model of endometriosis at 0.1, 0.3, and 1 mg/kg per day for 21 days orally; reduces 17β-estradiol benzoate-dependent tumor growth in an MCF-7 ovariectomized mouse xenograft model at 0.1 and 1 mg/kg per day for 28 days