A Phase 2 interventional study of Elacestrant in ER+ Breast Cancer, sponsored by Yale University. Recruiting at 7 sites in United States. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-09-21.
Sponsored by Yale University · Phase 2, Interventional, and Treatment
This is a single-arm, phase II study examining elacestrant in the adjuvant treatment of patients with ER+ breast cancer who test positive for circulating tumor DNA (ctDNA) during the screening period of the trial. Our trial will proceed in three separate phases: screening, treatment, and follow-up.
This is a single-arm, phase II study examining elacestrant in the adjuvant treatment of patients with ER+ breast cancer who test positive for circulating tumor DNA (ctDNA) during the screening period of the trial. Patients with ER+ breast cancer anatomic stage IIB or III at diagnosis who are at least five years from diagnosis and have completed intended course of adjuvant endocrine therapy and are currently off endocrine therapy will be screened with ctDNA testing via the NEXT Personal MRD Detection test from Personalis. Patients who test positive for ctDNA during the screening phase will receive treatment with elacestrant for one year and continue ctDNA testing and imaging with CT scans every three months. During the follow-up period, patients in the study will continue to be ctDNA tested every six months and monitored for one year. If patients remain ctDNA positive at the completion of 12 months of study treatment, since they remain at increased risk of recurrence, they can choose to continue for an additional 12 months for a maximum of 24 months, they may also resume standard endocrine therapy or continue with standard of care surveillance during follow up.
Yale University is the lead sponsor of 1,724 studies on the registry; 298 are open to participants now.
Of its 210 completed or terminated interventional studies of FDA-regulated products, 126 (60%) have results posted.
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Inclusion Criteria for Screening:
Exclusion Criteria for Screening:
Current or past invasive cancer other than breast cancer, except:
Inclusion Criteria for Treatment:
No evidence of metastatic disease on staging scans.
a. If imaging, after review with a radiologist, is low probability for metastatic disease, patients may proceed with enrollment. Patients with suspicious but inconclusive imaging results should undergo a diagnostic biopsy; if biopsy is negative patients are eligible for enrollment. Patients with positive imaging that is conclusive of metastatic disease, or biopsy proven metastatic disease, are not eligible.
At the time of informed consent signature for treatment, participants may be either postmenopausal, premenopausal, or perimenopausal.
a. Postmenopausal status is defined by: i. Age ≥60. ii. Age \<60 and amenorrhea for 12 or more months (without an alternative cause) and FSH and estradiol level within postmenopausal range per local laboratory reference.
iii. Documentation of bilateral oophorectomy, at least one month before first dose of trial therapy.
b. Premenopausal and perimenopausal participants must be willing to concurrently receive an LHRH agonist, and the LHRH agonist must be initiated at least three to four weeks before the start of elacestrant and are planning to continue LHRH agonist treatment during treatment with elacestrant. This is based on the current FDA approval of elacestrant in the metastatic setting which is limited to postmenopausal participants.
c. Premenopausal or perimenopausal participants must be willing to use a highly effective method of contraception for the duration of trial treatment and for 120 days after the last dose of elacestrant OR if using barrier method of contraception must be willing to use a second form of contraception like occlusive cap with spermicidal foam / gel / film / cream / suppository.
i. Highly effective methods of contraception are non-hormonal (cooper) intrauterine device (IUD), surgical sterilization (bilateral tubal occlusion/ligation, partner who has had a vasectomy), and sexual abstinence.
Patient has adequate bone marrow and organ function, as defined by the following laboratory values:
Exclusion Criteria for Treatment:
Administration of elacestrant will follow the FDA approved dose and schedule for patients with ER+ metastatic breast cancer. Elacestrant 345 mg will be administered orally once daily for 12 cycles or until disease progression or unacceptable toxicity
Drug: Elacestrant
Administration of elacestrant will follow the FDA approved dose and schedule for patients with ER+ metastatic breast cancer. Elacestrant 345 mg will be administered orally once daily for 12 cycles or until disease progression or unacceptable toxicity. The pills shall be administered with food (to reduce nausea and vomiting) at approximately the same time each day, and the prescription will be provided with the standard "Swallow tablets whole; do not chew, crush, or split" warning label.
Assessing Elacestrant's Impact on ctDNA Clearance in ER+HER2- Breast Cancer Patients
This study evaluates whether treatment with elacestrant improves the clearance of circulating tumor DNA (ctDNA) in patients with estrogen receptor-positive (ER+), human epidermal growth factor receptor 2-negative (HER2-) breast cancer. Patients included in the study have detectable ctDNA in their plasma but show no evidence of metastatic disease on imaging, and the results will be compared against historical control data.
Time frame: Every 3 months during the treatment phase and at 3-month intervals for 12 months following the end of treatment
Investigating Elacestrant's Effect on 18-Month Invasive Disease-Free Survival in ER+HER2- Breast Cancer Patients
To determine whether treatment with elacestrant improves the 18-month invasive disease-free survival rate in patients with estrogen receptor-positive (ER+), human epidermal growth factor receptor 2-negative (HER2-) breast cancer. The study focuses on patients with detectable circulating tumor DNA (ctDNA) in their plasma but who have no observable metastatic disease on imaging, comparing the outcomes to historical controls.
Time frame: From the start of treatment through 18 months post-initiation of treatment
Incidence of ctDNA Positivity in Screened ER+HER2- Breast Cancer Patients
To estimate the incidence rate of circulating tumor DNA (ctDNA) positivity among patients screened for the study who have estrogen receptor-positive (ER+), human epidermal growth factor receptor 2-negative (HER2-) breast cancer.
Time frame: At baseline screening prior to treatment
Proportion of Patients with Metastatic Disease at First Positive ctDNA Result
This secondary outcome measure estimates the proportion of patients who present with clinically apparent metastatic disease (evident on imaging) at the time of their first positive ctDNA result.
Time frame: From baseline screening through the first positive ctDNA detection, up to 12 months
Time to Relapse Between First Positive ctDNA and Clinical Recurrence of Metastatic Disease
To assess the duration between the first detection of positive ctDNA and the clinical recurrence of metastatic disease, as confirmed by imaging.
Time frame: From the first positive ctDNA detection through clinical recurrence, up to 24 months
Association of ctDNA Clearance with Recurrence-Free Survival and Overall Survival
To evaluate whether clearance of ctDNA is associated with improved recurrence-free survival (RFS) and overall survival (OS) in ER+HER2- breast cancer patients
Time frame: From baseline through 36 months post-treatment initiation
Safety, Tolerability, and Adherence to Elacestrant Treatment Protocol
To assess the safety and tolerability of the elacestrant treatment, as well as patients' adherence to the treatment protocol.
Time frame: From baseline through the end of the treatment phase, up to 18 months
Patient-Reported Outcomes, Fear of Recurrence and Anxiety Levels During Elacestrant Treatment
To evaluate global patient-reported outcomes , fear of recurrence and anxiety levels during the elacestrant treatment phase.
Time frame: From baseline through the end of the treatment phase, assessed every 3 months up to 18 months
Assessing AmDTx-MBCS' Impact on Decreasing Fear of Recurrence Scores
AmDTx-MBCS is a mobile health platform that combines psychoeducation, mindfulness/meditation, and cognitive based therapy practices. Investigators will evaluate the effect of AmDTx-MBCS on global patient-reported outcomes , fear of recurrence and anxiety levels during the elacestrant treatment phase.
Time frame: Participation in the application will be offered at the first screening visit. Fear of recurrence will be assessed from baseline through the end of the treatment phase, assessed every 3 months up to 18 months.
Diet and Physical Activity Levels in Breast Cancer Patients
To assess self reported diet and physical activity levels among screened participants via Behavioral Risk Factor Surveillance System (BRFSS) and International Physical Activity Questionnaires (IPAQ) questionnaires.
Time frame: At the first screening visit only
Plan to share: No
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