Elacestrant dihydrochloride (RAD1901 dihydrochloride) (Synonyms: RAD1901 dihydrochloride)

Elacestrant dihydrochloride (RAD1901 dihydrochloride) is a selective and orally available estrogen receptor (ERR) degrader with IC50 values of 48 and 870 nM for ERα and ERβ, respectively.

RAD1901 selectively binds to and degrades the ER and is a potent antagonist of ER-positive breast cancer cell proliferation. RAD1901 treatment exhibits dose-dependent inhibition of ERα expression, with an EC50 of 0.6 nM. Treatment of ER-positive MCF-7 cells with E2 results in a potent and dose-dependent increase in proliferation, with an EC50 of 4 pM. Treatment of cells with RAD1901 in the presence of 10 pM E2 resultsin a dose-dependent decrease in proliferation, with an IC50 value of 4.2 nM[1].

RAD1901 produces a robust and profound inhibition of tumor growth in MCF-7 xenograft models. RAD1901-treated animals survived longer than those treated with either control or fulvestrant. RAD1901 preserves ovariectomy-induced bone loss and preventes the uterotropic effects of E2[1].

[1]. Garner F, et al. RAD1901: a novel, orally bioavailable selective estrogen receptor degrader that demonstrates antitumor activity in breast cancer xenograft models. Anticancer Drugs. 2015 Oct;26(9):948-56.