Estrogen Receptor-positive Breast Cancer Clinical Trials

9 recruitingLast updated: June 17, 2026

There are 9 actively recruiting estrogen receptor-positive breast cancer clinical trials across 2 countries. Studies span Phase 2, Not Applicable. Top locations include Houston, Texas, United States, Rochester, Minnesota, United States, Boston, Massachusetts, United States. Updated daily from ClinicalTrials.gov.


Estrogen Receptor-positive Breast Cancer Trials at a Glance

9 actively recruiting trials for estrogen receptor-positive breast cancer are listed on ClinicalTrialsFinder across 6 cities in 2 countries. The largest study group is Phase 2 with 8 trials, with the heaviest enrollment activity in Houston, Rochester, and Boston. Lead sponsors running estrogen receptor-positive breast cancer studies include Baylor Breast Care Center, Dana-Farber Cancer Institute, and Atossa Therapeutics, Inc..

Browse estrogen receptor-positive breast cancer trials by phase

Treatments under study

About Estrogen Receptor-positive Breast Cancer Clinical Trials

Looking for clinical trials for Estrogen Receptor-positive Breast Cancer? There are currently 9 studies actively recruiting participants. Clinical trials offer access to new treatments before they are widely available, and every approved therapy in use today was first tested through a clinical trial.

Below you can browse trials, sign up for alerts when new Estrogen Receptor-positive Breast Cancer trials open, and view eligibility criteria for each study. Each listing includes the study phase, locations, and enrollment details.

Frequently Asked Questions

Common questions about Estrogen Receptor-positive Breast Cancer clinical trials

A clinical trial is a carefully designed research study that tests new medical treatments, drugs, devices, or approaches in human volunteers. Every approved medication and treatment available today was proven safe and effective through clinical trials.

All clinical trials are reviewed and approved by Institutional Review Boards (IRBs) — independent committees that evaluate patient safety. Trials follow strict protocols, and your health is monitored closely throughout. You can withdraw at any time.

Not necessarily. Many trials compare the new treatment against the current standard of care, meaning all participants receive active treatment. When placebos are used, they are typically combined with standard treatment, not given alone. The trial description will always specify the design.

Under the Affordable Care Act, most private insurers are required to cover routine patient care costs during a clinical trial. The sponsor typically covers the investigational treatment itself. Medicare also covers routine costs for qualifying trials.

Yes. Participation is completely voluntary. You can withdraw at any time, for any reason, without it affecting your access to standard medical care.

Each trial has specific eligibility criteria — including age, diagnosis, disease stage, prior treatments, and general health. Browse the trials listed above and check their eligibility sections. You can also contact the trial site directly to discuss your situation.

Showing 19 of 9 trials

Recruiting
Phase 2

PhII Randomized CAPecitabine + ELAcestrant vs. Capecitabine Alone in ER+ Breast Cancer (CAPELA)

Breast CancerMetastatic Breast CancerBreast Neoplasms+6 more
Kristina A. Fanucci297 enrolled1 locationNCT07222215
Recruiting
Phase 2

Evolutionary Clinical Trial for Novel Biomarker-Driven Therapies

Breast CancerTriple-Negative Breast CancerMetastatic Breast Cancer+2 more
UNC Lineberger Comprehensive Cancer Center700 enrolled2 locationsNCT07340541
Recruiting
Phase 2

Adaptive Therapy With Capecitabine for Treatment of Metastatic ER Positive, HER2 Negative Breast Cancer

Metastatic Breast CancerAnatomic Stage IV Breast Cancer AJCC v8Estrogen Receptor-positive Breast Cancer+1 more
Mayo Clinic35 enrolled1 locationNCT06525766
Recruiting
Not Applicable

Breast Re-irradiation After Second Ipsilateral Lumpectomy

Breast CancerCancer of the BreastHER2-negative Breast Cancer+3 more
Youssef Zeidan114 enrolled2 locationsNCT06867484
Recruiting
Phase 2

(Z)-Endoxifen for the Treatment of Premenopausal Women With ER+/HER2- Breast Cancer

Breast NeoplasmsHER2-negative Breast CancerInvasive Breast Cancer+1 more
Atossa Therapeutics, Inc.87 enrolled15 locationsNCT05607004
Recruiting
Phase 2

Elacestrant vs Elacestrant Plus a CDK4/6 Inhibitor in Patients With ERpositive/HER2-negative Advanced or Metastatic Breast Cancer

Metastatic Breast CancerEstrogen Receptor-positive Breast CancerHER2/Neu-Negative Breast Cancer+1 more
Northwestern University174 enrolled1 locationNCT06062498
Recruiting
Phase 2

The SAPPHO Study: Sequential Therapy With Curative Intent in de Novo HER2+ Metastatic Breast Cancer

Breast CancerBreast Cancer MetastaticBreast Cancer Female+3 more
Dana-Farber Cancer Institute72 enrolled1 locationNCT06439693
Recruiting
Phase 2

Ketorolac and Pregabalin Effects on breaSt Cancer (KePreSt)

Estrogen Receptor-positive Breast CancerEarly Stage Breast Cancer
Jules Bordet Institute112 enrolled1 locationNCT06150898
Recruiting
Phase 2

Correlation of Clinical Response to Pathologic Response in Patients With Early Breast Cancer

Breast CancerTriple-Negative Breast CancerBreast Cancer Female+8 more
Baylor Breast Care Center185 enrolled2 locationsNCT05020860