The primary objective is to determine the maximum tolerated dose (MTD) and/or recommended Phase 2 dose (RP2D) of elacestrant in patients with advanced ER+HER2-negative breast cancer.~The secondary objectives of this study are:~To assess the safety and tolerability of elacestrant~To evaluate the pharmacokinetics (PK) of elacestrant~To evaluate the preliminary anti-tumor effect of elacestrant
The purpose of this study is to evaluate the safety, tolerability and preliminary efficacy of elacestrant (RAD1901) in patients with advanced ER+, HER2-negative breast cancer.