Elacestrant (oral SERD) + Everolimus mTOR Blockade Yields 81% 24-wk CBR in Pre-treated ER+/HER2- mBC

Elacestrant 258–345 mg QD combined with everolimus 5–10 mg (ELEVATE phase 1b; NCT05563220) enrolled 23 heavily pre-treated ER+/HER2- metastatic breast-cancer patients (all post-CDK4/6i); safety was dominated by mostly grade 1–2 nausea (57%), stomatitis (52%), diarrhea (43%) and fatigue (43%), with grade ≥3 events ≤9%. Among 16 response-evaluable patients, clinical-benefit rate at 24 weeks hit 81% and investigator-assessed ORR 25%, with median PFS not yet reached (0.8–12.3 mo follow-up). By contrast, everolimus + exemestane in BOLERO-2 achieved ORR 9% and central-review mPFS 10.6 mo, while single-agent elacestrant in EMERALD showed ORR ≈12% and mPFS 3.8 mo in an all-comers population, suggesting the new oral doublet may outperform each monotherapy backbone.

https://aacrjournals.org/clincancerres/article/31/12_Supplement/PS7-06/753562/Abstract-PS7-06-Elacestrant-combinations-in