EMERALD: Phase III trial of elacestrant (RAD1901) vs endocrine therapy for previously treated ER+ advanced breast cancer

Future Oncol. 2019 Oct;15(28):3209-3218. doi: 10.2217/fon-2019-0370. Epub 2019 Aug 20.


Elacestrant is a novel, nonsteroidal, orally bioavailable selective estrogen receptor degrader (SERD) that has demonstrated activity in patients with estrogen receptor (ER)-positive/HER2-negative breast cancer previously treated with endocrine therapies including fulvestrant and/or CDK 4/6 inhibitor therapy, and in those with ESR1 mutations (ESR1-mut) known to confer endocrine resistance. Herein, we describe the design and methodology of EMERALD, an international, multicenter, randomized, open-label, active-controlled, Phase III clinical study comparing the efficacy and safety of elacestrant to standard-of-care endocrine monotherapy treatment (fulvestrant or an aromatase inhibitor, per investigator's choice) in patients with ER-positive/HER2-negative advanced breast cancer. Primary end points are progression-free survival in ESR1-mut patients and in all patients (NCT03778931; EudraCT 2018-002990-24).

Keywords: ESR1 mutation; RAD1901; aromatase inhibitor; breast cancer; elacestrant; endocrine therapy; estrogen receptor (ER)-positive; fulvestrant; selective estrogen receptor degrader (SERD).

Publication types

  • Clinical Trial Protocol
  • Clinical Trial, Phase III
  • Comparative Study
  • Multicenter Study
  • Randomized Controlled Trial

MeSH terms

  • Antineoplastic Combined Chemotherapy Protocols / therapeutic use*
  • Breast Neoplasms / drug therapy*
  • Breast Neoplasms / metabolism
  • Breast Neoplasms / pathology
  • Estrogen Receptor alpha / metabolism*
  • Female
  • Follow-Up Studies
  • Fulvestrant / administration & dosage
  • Humans
  • International Agencies
  • Middle Aged
  • Prognosis
  • Prospective Studies
  • Survival Rate
  • Tetrahydronaphthalenes / administration & dosage


  • Estrogen Receptor alpha
  • Tetrahydronaphthalenes
  • elacestrant
  • Fulvestrant

Associated data

  • ClinicalTrials.gov/NCT03778931