PF-02413873 (PF-2413873) is a potent selective, fully competitive and orally active nonsteroidal progesterone receptor (PR) antagonist, with a Ki of 2.6 nM. PF-02413873 can block progesterone binding and PR nuclear translocation, and inhibit endometrial growth in vivo[1][2].
PF-02413873 shows potent PR antagonist activity with a derived Ki of 9.7 nM in the T47D native functional assay[1].PF-02413873 (1 nM-10 μM) induces nuclear translocation only at high concentrations (>3 μM)[1].
PF-02413873 (2.5 and 10 mg/kg; p.o. twice daily for 10 days) induces a statistically significant reduction in endometrial thickness in cynomolgus macaques[1].PF-02413873 (3 mg/kg; a single p.o.) exhibits t1/2 (4.2 h), Cmax (162 ng/mL) and CL/F (41 mL/min/kg)[1].
[1]. Howe DC, et, al. The translational efficacy of a nonsteroidal progesterone receptor antagonist, 4-[3-cyclopropyl-1-(mesylmethyl)-5-methyl-1H-pyrazol-4-yl]oxy,-2,6-dimethylbenzonitrile (PF-02413873), on endometrial growth in macaque and human. J Pharmacol Exp Ther. 2011 Nov;339(2):642-53.
[2]. Bungay PJ, et, al. Preclinical and clinical pharmacokinetics of PF-02413873, a nonsteroidal progesterone receptor antagonist. Drug Metab Dispos. 2011 Aug;39(8):1396-405.