In the phase 3 registrational trial, EMERALD, elacestrant demonstrated statistically significant progression-free survival (PFS) compared with treatment with standard endocrine monotherapy (fulvestrant, letrozole, anastrozole, exemestane). The study included 478 patients who were divided into two treatment arms. Participants were randomly assigned 1:1 to receive elacestrant at 400 mg or the investigator’s choice of either fulvestrant, anastrozole, letrozole, or exemestane. In a post hoc analysis of PFS based on the length of previous therapy with CDK4/6 inhibitors, it was shown that elacestrant demonstrated clinically meaningful outcomes in the entire patient population in addition to those with ESR1 mutations. Elacestrant was also associated with longer PFS in those who had a longer duration of previous CDK4/6 inhibitor treatment compared with standard of care.

Reference: EMERALD Trial: Elacestrant vs Standard Endocrine Monotherapy for Advanced Breast Cancer After CDK4/6 Inhibition. The ASCO Post. Updated January 5, 2023. Accessed January 12, 2023.