tanaproget is a novel agonist of progesterone receptor with ic50 of 1.7 nm [1].progesterone receptor (pr) is a member of the nuclear receptor superfamily and binding of progesterone causes pr conformational changes, which then changing gene expression. progesterone plays an important role in female reproduction [1].in t47d cells, tanaproget caused alkaline phosphatase activity with ec50 value of 0.1 nm. in a mammalian two-hybrid assay, tanaproget showed 50-fold more potent than progesterone. in stromal cells isolated from endometrial, tanaproget (1 nm) significantly suppressed pro-mmp-3 secretion. also, tanaproget effectively prevented pro-mmp-3 secretion through il-1α-mediated stimulation [2].in endometriosis mice model with human lesions growing on the parietal peritoneum of mice, tanaproget completely regressed human lesions in 58% treated animals. also, the lesions were smaller and fewer compared with the lesions in placebo-treated mice at the end of therapy [2]. in healthy women, the elimination half-life (t(1/2)) of tanaproget ranged from 12 to 30 h. tanaproget reduced cervical mucus scores, which suggesting poor production and quality of cervical mucus [3].
[1]. zhang z, olland am, zhu y, et al. molecular and pharmacological properties of a potent and selective novel nonsteroidal progesterone receptor agonist tanaproget. j biol chem, 2005, 280(31): 28468-28475.
[2]. bruner-tran kl, zhang z, eisenberg e, et al. down-regulation of endometrial matrix metalloproteinase-3 and -7 expression in vitro and therapeutic regression of experimental endometriosis in vivo by a novel nonsteroidal progesterone receptor agonist, tanaproget. j clin endocrinol metab, 2006, 91(4): 1554-1560.
[3]. bapst jl, ermer jc, ferron gm, et al. pharmacokinetics and safety of tanaproget, a nonsteroidal progesterone receptor agonist, in healthy women. contraception, 2006, 74(5): 414-418.
