Elacestrant for Treating ER+/HER2- Breast Cancer Patients With ctDNA Relapse (TREAT ctDNA)

This is an international, multi-center, randomised, open label, superiority phase III trial of elacestrant vs standard endocrine therapy in patients with ER+/HER2- breast cancer and ctDNA relapse. During the ctDNA screening phase, patients will be tested at different timepoints to detect the presence of ctDNA in their blood. Patients who are found to be ctDNA-positive and have no evidence of distant metastasis, will be randomised 1:1 between standard endocrine treatment (the same they were receiving when tested ctDNA positive) versus elacestrant, provided they meet all eligibility criteria. After completion of the protocol treatment period, treatment will be left at the discretion of the treating physician.

NCT Number	NCT05512364
Lead Sponsor	European Organisation for Research and Treatment of Cancer - EORTC Collaborators: Menarini Group, Natera, Inc., Borstkanker Onderzoek Groep, Cancer Trials Ireland, SOLTI Breast Cancer Research Group, ETOP IBCSG Partners Foundation, SUCCESS, Hellenic Cooperative Oncology Group, Hellenic Oncology Research Group, Swedish Breast Cancer Group
Conditions	ER-positive Breast Cancer, HER2-negative Breast Cancer, Stage IIB Breast Cancer, Stage III Breast Cancer
Enrollment	220 participants
Start Date	2023-12-15
Primary Completion	2032-11-01 (estimated)
Study Completion	2035-11-01 (estimated)
Updated on ClinicalTrials.gov	2026-08-10