Ulipristal acetate-d6 is intended for use as an internal standard for the quantification of ulipristal acetate by GC- or LC-MS. Ulipristal acetate is a selective progesterone receptor modulator (SPRM) that binds to the human progesterone receptors PR-A and PR-B (EC50s = 8.5 and 7.7 nM, respectively), rabbit uterine PR (EC50 = 13.6 nM), and rabbit thymic glucocorticoid receptor (GR; EC50 = 15.4 nM).1 It is selective for human progesterone receptors over the human estrogen receptor (ER; EC50 = >10,000 nM). It inhibits growth of IGROV-1 and SK-OV-3 human ovarian cancer cells (IC50s = 15.5 and 31.5 μM, respectively) even after resistance to combined cisplatin and paclitaxel treatment has developed.2 Ulipristal acetate reverses the proliferative effect of progesterone on patient-derived germline mutant BRCA1 breast tissue xenografts in ovariectomized athymic mice.3 Ulipristal acetate (40 mg/kg, i.p.) administered to female mice within 6 hours of human chorionic gonadotropin (hCG) treatment inhibits ovulation.4 Formulations containing ulipristal acetate have been used as emergency contraceptives and to treat uterine fibroids.
1.Attardi, B.J., Burgenson, J., Hild, S.A., et al.In vitro antiprogestational/antiglucocorticoid activity and progestin and glucocorticoid receptor binding of the putative metabolites and synthetic derivatives of CDB-2914, CDB-4124, and mifepristoneJ. Steroid Biochem. Mol. Biol.88(3)277-288(2004) 2.Gamarra-Luques, C.D., Hapon, M.B., Goyeneche, A., et al.Resistance to cisplatin and paclitaxel does not affect the sensitivity of human ovarian cancer cells to antiprogestin-induced cytotoxicityJ. Ovarian Res.7:45(2014) 3.Communcal, L., Vilasco, M., Hugon-Rodin, J., et al.Proliferation and ovarian hormone signaling are impaired in normal breast tissues from women with BRCA1 mutations: Benefit of a progesterone receptor modulator treatment as a breast cancer preventive strategy in women with inherited BRCA1 mutationsOncotarget7(29)45317-45330(2016) 4.Nallasamy, S., Kim, J., Sitruk-Ware, R., et al.Ulipristal blocks ovulation by inhibiting progesterone receptor-dependent pathways intrinsic to the ovaryReprod. Sci.20(4)371-381(2013)