Condition

ER+ Breast Cancer clinical trials and research

• 13Clinical trials
• 28NIH research projects
• 6Countries

Newest ER+ Breast Cancer clinical trials

All recruiting trials (13)

• Pre-surgery hormone therapy to lower positive margins in lobular breast cancer

  This Phase 2 trial tests whether giving endocrine (hormone) therapy before breast-conserving surgery can reduce the chance of cancer at the edges of the removed tissue in postmenopausal people with ER+/HER2- invasive lobular breast cancer.

  Recruiting at 7 sites Phase 2 Memorial Sloan Kettering Cancer Center · Basking Ridge, New Jersey and 6 other locations · NCT07483307

• Adherence to Cell Cycle Inhibitors with Endocrine Therapy in Localized High-Risk ER+ Breast Cancer

  This study checks how well patients with localized ER+ breast cancer stick to a combined endocrine therapy and CDK4/6 inhibitor after surgery.

  Recruiting University Hospital, Grenoble · Grenoble · NCT07443774

• Combining FWD1802 with CDK4/6 inhibitors or everolimus for ER+/HER2- advanced breast cancer

  This trial tests whether adding FWD1802 to CDK4/6 inhibitors or everolimus helps people with ER-positive/HER2-negative unresectable locally advanced or metastatic breast cancer who have progressed on or cannot use standard therapy.

  Recruiting Phase 1/2 Forward Pharmaceuticals Co., Ltd. · Shanghai · NCT07002177

• ctDNA-guided elacestrant for ER+ breast cancer

  This trial will test whether giving elacestrant for one year to people with ER+, stage IIB/III breast cancer who have a positive ctDNA test after finishing endocrine therapy can eliminate hidden cancer and lower the chance of recurrence.

  Recruiting at 6 sites Phase 2 Yale University · New Haven, Connecticut and 6 other locations · NCT06923527

• Re‑irradiating the breast after a second lumpectomy

  This trial will test whether targeted re‑irradiation (IMRT) after a second lumpectomy is safe for people with ER+ / HER2‑ breast cancer who previously received breast radiation.

  Recruiting at 2 sites Baptist Health South Florida · Boca Raton, Florida and 1 other locations · NCT06867484

• Understanding breast cancer response during pre-surgery treatment

  This study is trying to see how breast cancer responds to treatment before surgery by looking at tissue and blood samples from patients to find out what factors might affect their recovery and risk of cancer coming back.

  Recruiting Royal Marsden NHS Foundation Trust · London · NCT06681064

• Treatment for advanced breast cancer using RYZ101

  This study is testing a new treatment called RYZ101 for people with advanced breast cancer that can't be removed by surgery to see if it helps manage their condition.

  Recruiting Phase 1/2 RayzeBio, Inc. · Phoenix, Arizona and 30 other locations · NCT06590857

• Testing a new drug ETX-19477 for advanced solid tumors

  This study is testing a new drug called ETX-19477 to see if it can help people with advanced solid tumors that haven't responded to other treatments.

  Recruiting at 14 sites Phase 1/2 858 Therapeutics, Inc. · Phoenix, Arizona and 13 other locations · NCT06395519

• Adding targeted radiation therapy to drug treatment for breast cancer

  This study is testing whether adding targeted radiation therapy to regular drug treatment can help people with a specific type of breast cancer keep their disease from getting worse or spreading.

  Recruiting at 7 sites Phase 2 Memorial Sloan Kettering Cancer Center · Basking Ridge, New Jersey and 7 other locations · NCT05534438

• Evaluating JAB-2485 for Advanced Solid Tumors

  This study is testing a new drug called JAB-2485 to see if it is safe and can help adults with advanced solid tumors, like certain types of breast cancer and lung cancer, who have already tried other treatments.

  Recruiting at 8 sites Phase 1/2 Jacobio Pharmaceuticals Co., Ltd. · Detroit, Michigan and 7 other locations · NCT05490472

• Detecting and treating early breast cancer relapse using ctDNA analysis

  This study is testing if checking for cancer DNA in the blood can help catch early breast cancer relapses in women with a specific type of breast cancer and see if treating those at risk with a new combination of medications can improve their chances of staying cancer-free.

  Recruiting at 42 sites Phase 2 Royal Marsden NHS Foundation Trust · Angers and 48 other locations · NCT04985266

• Imaging Estrogen Receptor Positive Advanced Breast Cancers

  This study is testing a new type of PET imaging to see if it can help doctors better understand estrogen receptor levels in patients with advanced breast cancer, which may improve their treatment options.

  Recruiting Phase 2 Centre de recherche du Centre hospitalier universitaire de Sherbrooke · Sherbrooke, Quebec · NCT04824014

• Using imaging to optimize tamoxifen treatment for metastatic breast cancer

  This study is testing if special imaging can help doctors find the best dose of tamoxifen for patients with metastatic breast cancer who have certain mutations and may not respond well to standard treatment.

  Recruiting Early Phase 1 University of Wisconsin, Madison · Madison, Wisconsin and 1 other locations · NCT04174352

NIH-funded research (28)

Early-stage science funded by the US National Institutes of Health. Most of these projects don't enroll patients, but they show what is being worked on.

• ER+ Breast Cancer Bone Metastasis in a Real Body Environment

  This grant aims to understand why estrogen receptor alpha–positive breast cancer often spreads to bone and how the bone environment and immune system affect treatment resistance.

  NIH research Baylor College of Medicine · Houston, United States · NIH-11422333

• Targeting RAGE to fight obesity-related ER+ breast cancer and its drug resistance

  A scientist team will explore how obesity-related inflammation involving RAGE and estrone interacts with ER+ breast cancer to drive growth and spread, aiming to find strategies to overcome therapy resistance.

  NIH research Georgetown University · Washington, United States · NIH-11364105

• Understanding estrogen signals in bone to stop ER+ breast cancer spread

  This NIH grant aims to uncover how estrogen signals inside bone help ER-positive breast cancer cells grow and spread, with the goal of finding better ways to prevent bone metastasis.

  NIH research University of Arizona · Tucson, United States · NIH-11364029

• Progesterone Receptor Signaling and Dormancy in ER+ Breast Cancer

  Researchers are studying how hormone signals in ER+/PR+ breast cancer influence cancer cell dormancy and later recurrence.

  NIH research University of Minnesota · Minneapolis, United States · NIH-11363974

• Heavy Metals and Breast Cancer Treatment Resistance

  This project explores how exposure to heavy metals might make ER+ breast cancer harder to treat and how we might overcome this challenge.

  NIH research H. Lee Moffitt Cancer Ctr & Res Inst · Tampa, United States · NIH-11349797

• Turning ER-positive breast cancer into a viral target for immune attack

  This project aims to wake up viral-like bits inside ER-positive breast cancer cells so the immune system can spot and attack them.

  NIH research Sanford Burnham Prebys Medical Discovery Institute · La Jolla, United States · NIH-11308203

• Improving CDK7-targeted treatments for estrogen receptor–positive (ER+) breast cancer

  This project looks at whether drugs that block CDK7, alone or combined with other medicines, can overcome resistance in ER+ breast cancers that no longer respond to hormone therapy and CDK4/6 inhibitors.

  NIH research Dana-Farber Cancer Inst · Boston, United States · NIH-11304636

• New rat models for estrogen receptor–positive (ER+) breast cancer

  Researchers are creating rat versions of ER+ breast cancer that behave like the human disease and spread to bone so scientists can develop better ways to prevent and treat recurrence.

  NIH research Baylor College of Medicine · Houston, United States · NIH-11294283

• How a protein switch may drive ER-positive breast cancer to resist treatment and spread

  This project looks at whether changes between two proteins, SIM2s and SEMA7A, help estrogen receptor–positive (ER+) breast cancers stop responding to hormone drugs and become more aggressive.

  NIH research University of Colorado Denver · Aurora, UNITED STATES · NIH-11284024

• Why some estrogen-positive breast cancers keep growing without estrogen

  This research looks for why some estrogen-receptor positive (ER+) breast cancers continue to grow despite hormone therapy and CDK4/6 drugs, aiming to help people with early-stage ER+ breast cancer.

  NIH research Beckman Research Institute/city of Hope · Duarte, United States · NIH-11211302

• Why some ER-positive breast cancers grow without estrogen

  Learning how some ER-positive breast cancers start growing again without estrogen, to help people with ER+ breast cancer get better treatment.

  NIH research Beckman Research Institute/city of Hope · Duarte, United States · NIH-11166394

• Blocking Inflammation and Drug Resistance in Obesity-Related Breast Cancer

  This project explores how inflammation linked to obesity makes estrogen receptor-positive breast cancer more aggressive and resistant to treatment.

  NIH research Georgetown University · Washington, United States · NIH-11129830

• How heavy metals affect breast cancer treatment and progression

  This study is looking at how being exposed to heavy metals like arsenic and lead might make certain types of breast cancer more aggressive and harder to treat, with the goal of finding new ways to help patients with hormone receptor-positive breast cancer.

  NIH research Northwestern University at Chicago · Chicago, United States · NIH-11124190

• Understanding how a specific estrogen receptor affects therapy-resistant breast cancer progression

  This study is looking at how a specific receptor called GPER in certain cells around breast tumors might affect the growth and spread of estrogen receptor positive breast cancer that doesn't respond to treatment, especially in patients who have trouble with tamoxifen.

  NIH research University of Wisconsin-Madison · Madison, United States · NIH-11080756

• Investigating how bromodomains affect breast cancer treatment responses

  This study is looking at how certain proteins affect the success of anti-estrogen treatments for the most common type of breast cancer, with the goal of finding better ways to help patients who struggle with treatment resistance.

  NIH research University of Vermont & St Agric College · Burlington, United States · NIH-11074068

• Using viral mimicry to target estrogen receptor-positive breast cancer

  This study is exploring a new way to treat estrogen receptor-positive breast cancer by blocking a protein called FBXO44, which might help wake up certain parts of the cancer cells to boost your immune system's ability to fight the tumor.

  NIH research Sanford Burnham Prebys Medical Discovery Institute · La Jolla, United States · NIH-11061322

• Investigating how a protein switch affects the progression of estrogen receptor positive breast cancer

  This study is looking at how a protein called Semaphorin 7a (SEMA7A) affects the growth and treatment resistance of estrogen receptor positive (ER+) breast cancer, with the goal of finding better treatment options for patients facing this challenging condition.

  NIH research University of Colorado Denver · Aurora, UNITED STATES · NIH-11044999

• Creating new rat models to study estrogen receptor-positive breast cancer

  This study is creating special rat models that closely mimic a common type of breast cancer to help researchers understand how the cancer grows and spreads, especially to bones, which could lead to better ways to prevent and treat the disease.

  NIH research Baylor College of Medicine · Houston, United States · NIH-11044083

• Targeting a specific protein complex to improve treatment for estrogen receptor positive breast cancer

  This study is looking at how specific proteins might help estrogen receptor positive breast cancer grow and resist treatment, with the goal of finding new ways to improve care for patients facing this type of cancer.

  NIH research University of Minnesota · Minneapolis, United States · NIH-11009067

• Understanding how breast cancer cells grow without estrogen

  This study is looking into how some breast cancer cells that usually need estrogen to grow can keep multiplying even without it, which could help doctors find better treatments for patients with early-stage breast cancer.

  NIH research Beckman Research Institute/city of Hope · Duarte, United States · NIH-10977526

• Understanding how breast cancer cells grow without estrogen

  This study is looking into how certain breast cancer cells can grow without needing estrogen, which could help find new ways to treat early-stage breast cancer for patients like you.

  NIH research Beckman Research Institute/city of Hope · Duarte, United States · NIH-10977525

• Understanding how breast cancer cells grow without estrogen

  This study is looking into how some breast cancer cells can grow without needing estrogen, which could help doctors find better treatments for patients with early-stage breast cancer.

  NIH research Beckman Research Institute/city of Hope · Duarte, United States · NIH-10909954

• Understanding how aging affects the progression of ER+ breast cancer in older women

  This study looks at how breast cancer behaves in women aged 70 and older, especially those with estrogen receptor positive (ER+) cancer, to see if some aggressive treatments can be skipped without harming their chances of living longer, all while considering how aging and inflammation affect their condition.

  NIH research University of Pittsburgh at Pittsburgh · Pittsburgh, United States · NIH-10898759

• Investigating how obesity affects breast cancer growth and treatment resistance

  This study is looking at how being overweight might raise the risk of a certain type of breast cancer in women after menopause, and it aims to find new ways to improve treatment by understanding how inflammation and hormones play a role in this connection.

  NIH research Georgetown University · Washington, United States · NIH-10884269

• Investigating the role of long non-coding RNAs in ER+ breast cancer

  This study is looking at special molecules in breast cancer that has estrogen receptors to see how they might affect the way the cancer grows and responds to treatment, with the hope of finding better, more personalized treatment options for patients like you.

  NIH research University of Virginia · Charlottesville, United States · NIH-10884218

• Investigating how FBXL16 contributes to breast cancer treatment resistance and spread

  This study is looking at how a protein called FBXL16 influences estrogen receptor-positive breast cancer, especially why some patients don’t respond to hormone therapy and how the cancer might spread, with the goal of finding better treatment options for those facing advanced breast cancer.

  NIH research Wright State University · Dayton, United States · NIH-10794658

• Understanding how progesterone receptor signaling affects estrogen-positive breast cancer

  This study is looking at how different types of progesterone receptors affect the growth of estrogen-positive breast cancer, especially in cases where common treatments like tamoxifen aren't working, to find new ways to help patients with recurring breast cancer feel better and respond to treatment.

  NIH research University of Minnesota · Minneapolis, United States · NIH-10774285

• Investigating factors affecting survival rates in African American women with ER+ breast cancer

  This study is looking into why African American women with a specific type of breast cancer tend to have lower survival rates than white women, focusing on a particular enzyme that might be causing this issue, with the goal of finding better treatment options just for them.

  NIH research University of Illinois at Chicago · Chicago, UNITED STATES · NIH-10758961

Related topics

Quick answers

How many ER+ Breast Cancer clinical trials are recruiting right now?

13, as of November 12, 2026. We update this list each time we refresh our data from ClinicalTrials.gov.

Where are these trials running?

In 6 countries. The most sites are in United States (8 trials), China (2 trials), United Kingdom (2 trials), Canada (2 trials), France (2 trials). Each study page lists its sites and which ones are recruiting.

What phases are they in?

Phase 2: 5, Phase 1/2: 4, Early Phase 1: 1. Trials with no phase listed are usually device, behavioural or observational studies.

How do I join one?

Open a study, check the "Is this trial a fit for you?" section, then contact the study team listed on the page. They will ask a few screening questions. Asking is free and does not commit you to anything. Talk it over with your doctor first.

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