Estrogen Receptor Positive Breast Cancer

11

Review clinical trials related to Estrogen Receptor Positive Breast Cancer. Use filters to narrow results by trial status, phase, treatment, biological sex and sponsor.

Condition / disease
Location
Status: Recruiting

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

Breast cancer is not only the leading cause of cancer in women, but also the leading cause of cancer deaths in women. Estrogen receptor-positive and HER2-negative breast cancer is the most prevalent breast cancer subtype. Endocrine therapy is the mainstay of treatment; however, due to the varied nature of the disease, development of resistance to this therapeutic approach is very common in the metastatic setting. The purpose of this study is to see whether the effectiveness of elacestrant can be enhanced by combining it with a targeted agent such as a CDK4/6 inhibitor to treat patients with ER+/HER2- or metastatic breast cancer with prior exposure to a CDK4/6 inhibitor.

Participants needed: 174
Trial details
Phase: Phase 2Age: 18+Biological sex: AllType: InterventionalSponsor: Northwestern UniversityUpdated: Jul 2, 2026Locations: 3
Eligibility criteria

Patients must have histologically or cytologically confirmed ER-positive and HER... [+20]

Patients who have received prior elacestrant. [+14]

Status: Recruiting

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

The goal of this research study is to compare a combination of two drugs, capecitabine and elacestrant to capecitabine alone as a treatment for advanced estrogen receptor-positive (ER+) breast cancer. This study is designed for participants with cancer that has previously stopped responding to medication in the class of therapy called CDK 4/6 inhibitors, including palbociclib, ribociclib, or abemaciclb. The names of the study drugs involved in this study are: * Elacestrant (a type of selective estrogen receptor degrader) * Capecitabine (a type of fluoropyrimidine antimetabolite)

Participants needed: 297
Trial details
Phase: Phase 2Age: 18+Biological sex: AllType: InterventionalSponsor: Kristina A. FanucciUpdated: Jun 12, 2026Locations: 1
Eligibility criteria

Participants must have histologically confirmed estrogen receptor-positive (ER+)... [+39]

Participants who have had endocrine and/or biologic therapy < 14 days prior to e... [+11]

Status: Recruiting

Evolutionary Clinical Trial for Novel Biomarker-Driven Therapies

This is a multicenter, multi-arm, biomarker-stratified trial designed to evaluate biomarker-directed therapies in patients with estrogen receptor-positive/hormone receptor-negative (ER+/HR-) and triple-negative (TN) metastatic breast cancer (MBC). The trial integrates both retrospective and prospective data collection, including archival tumor tissue, medical record abstraction, and prospective tumor and blood sampling prior to initiation of protocol directed treatment. Based on biomarker subtype, participants will receive standard of care therapy. Liquid biopsy will be collected on Cycle 2 Day 1, and then liquid biopsy, imaging and clinical data will be collected at each re-staging. Treatment will continue until discontinuation for progression, toxicity or at the discretion of the treating physician.

Participants needed: 700
Trial details
Phase: Phase 2Age: 18+Biological sex: AllType: InterventionalSponsor: UNC Lineberger Comprehensive Cancer CenterUpdated: May 20, 2026Locations: 2
Eligibility criteria

Written informed consent obtained to participate in the study and HIPAA authoriz... [+4]

Inaccessible metastatic lesion to research biopsy [+2]

Status: Recruiting

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

This phase II trial evaluates the effect of capecitabine on tumor response using imaging and tumor markers to adjust dose (adaptive therapy) in patients with estrogen receptor (ER) positive, HER2 negative breast cancer that has spread from where it first started to other areas in the body (metastatic). Capecitabine is in a class of medications called antimetabolites. It is taken up by tumor cells and breaks down into fluorouracil, a substance that kills tumor cells. Adaptive therapy with capecitabine based on tumor burden response may slow or stop the growth of tumor cells in patients with metastatic ER positive, HER2 negative breast cancer.

Participants needed: 35
Trial details
Phase: Phase 2Age: 18+Biological sex: AllType: InterventionalSponsor: Mayo ClinicUpdated: May 11, 2026Locations: 1
Eligibility criteria

Age ≥ 18 years [+16]

Prior chemotherapy or use of antibody drug conjugate in the metastatic setting [+20]

Status: Not yet recruiting

Randomized Double-Blind Phase II Trial of Baby Exemestane Versus Baby Tamoxifen in Post-Menopausal Women at High Risk for Breast Cancer

The goal of this research study is to evaluate the efficacy and safety of low-dose exemestane versus low-dose tamoxifen in post-menopausal women at high risk for breast cancer. The names of the study drugs involved in this study are: * Exemestane (a type of steroidal aromatase inhibitor) * Tamoxifen (a type of selective estrogen receptor modulator)

Participants needed: 140
Trial details
Phase: Phase 2Biological sex: FemaleType: InterventionalSponsor: Dana-Farber Cancer InstituteUpdated: Mar 30, 2026Locations: 2
Eligibility criteria

Postmenopausal state is defined⁸ as no menses for 12 months without an alternati... [+12]

Pre/perimenopausal women: exemestane is only effective in post-menopausal women [+15]

Status: Recruiting

Breast Re-irradiation After Second Ipsilateral Lumpectomy

The purpose of this research study is to test the safety and possible harms of treating breast cancer with reirradiation, after breast surgery. The researchers want to find out what effects (good and bad) reirradiation has on people who have already received radiation before surgery.

Participants needed: 114
Trial details
Age: 40+Biological sex: FemaleType: InterventionalSponsor: Youssef ZeidanUpdated: Nov 13, 2025Locations: 2
Eligibility criteria

Diagnosed with ER+HER2- breast cancer [+13]

BRCA1/2 mutation or any other receptor subtypes [+8]

Status: Recruiting

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

This open-label research study is studying (Z)-endoxifen as a possible treatment for pre-menopausal women with ER+/HER2- breast cancer. (Z)-endoxifen belongs to a group of drugs called selective estrogen receptor modulators or "SERM", which help block estrogen from attaching to cancer cells. This study has two parts: a pharmacokinetic part and a treatment part. The PK part (how the body processes the drug) will enroll about 18 participants. All participants will take (Z)-endoxifen capsules daily. Twelve participants will be randomly assigned (50/50 chance) to take (Z)-endoxifen alone or (Z)-endoxifen with a monthly injection of goserelin a drug that temporarily stops the ovaries from making estrogen. This part will help determine the best dose of (Z)-endoxifen by measuring the drug levels in the blood and how long the body takes to remove it. The Treatment Cohort has been simplified to a single study arm (Z)-endoxifen + goserelin. Up to 20 participants will be enrolled that have a baseline Ki-67 ≤ 10% and 45 participants will be enrolled that have a baseline Ki-67\>10%. A key goal of the study is to see if (Z)-endoxifen can slow down or stop tumor growth as measured by a reduction in Ki-67 levels. Tumor tissue samples will be taken by breast biopsy after about 4 weeks of treatment to check levels of this biomarker. If the tumor shows signs of response, participants can continue treatment for up to 24 weeks or until they have surgery. Study participation is up to 6 months (24 weeks of treatment) followed by surgery and a one-month follow up visit.

Participants needed: 87
Trial details
Phase: Phase 2Age: 18+Biological sex: FemaleType: InterventionalSponsor: Atossa Therapeutics, Inc.Updated: Oct 30, 2025Locations: 15
Eligibility criteria

Female sex assigned at birth. Female to male transgender individuals who have no... [+14]

Bilateral invasive breast cancer; Inflammatory breast cancer defined as clinical... [+22]

Status: Recruiting

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

The purpose of this study is to test the safety and effectiveness of a sequence of drugs (a Taxane plus Trastuzumab plus Pertuzumab followed by Trastuzumab Deruxtecan, followed by Tucatinib plus Ado-Trastuzumab Emtansine (T-DM1), followed by Trastuzumab plus Pertuzumab plus Tucatinib) in HER2+ Breast Cancer. The study will help investigators understand whether first intensifying therapy for a specific period and then stopping treatment is safe and effective for participants. The names of the study drugs involved in this study are: * Paclitaxel (a type of anti-microtubule agent) * Docetaxel (a type of anti-microtubule agent) * Nab-Paclitaxel (a type of anti-microtubule agent) * Trastuzumab (a type of IgG1 kappa monoclonal antibody) * Pertuzumab (a type of monoclonal antibody) * Trastuzumab Deruxtecan (a type of HER2-directed antibody drug conjugate) * Tucatinib (Tyrosine Kinase HER2 Inhibitor) * Ado-trastuzumab emtansine or T-DM1 (a type of HER2-targeted antibody-drug conjugate)

Participants needed: 72
Trial details
Phase: Phase 2Age: 18+Biological sex: AllType: InterventionalSponsor: Dana-Farber Cancer InstituteUpdated: Jun 26, 2025Locations: 1
Eligibility criteria

Participants must have histologically or cytologically confirmed unresectable lo... [+27]

Prior history of invasive breast carcinoma [+19]

Status: Recruiting

Ketorolac and Pregabalin Effects on breaSt Cancer (KePreSt)

Out of all proportion to its short duration, the perioperative period is critical in determining the long-term outcome of cancer. To contribute to a better understanding of the neural and inflammatory mechanisms underlying this issue, we aim to implement a novel intervention based on the preoperative use of non-steroidal anti-inflammatory drugs (NSAIDs) with or without an anti-epileptic drug. Our goal is to understand and transform the perioperative window from being a facilitator of metastatic progression to arresting and/or eliminating residual disease using repurposing drugs

Participants needed: 112
Trial details
Phase: Phase 2Age: 18-70Biological sex: FemaleType: InterventionalSponsor: Jules Bordet InstituteUpdated: Jun 13, 2025Locations: 1
Eligibility criteria

Age ≥ 18 years and ≤ 70 years old [+14]

Subject planned for intraoperative radiotherapy [+28]

Status: Recruiting

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

The purpose of this study is to learn whether clinical response (the amount a tumor shrinks based on imaging or tumor measurements obtained by physical exam) predicts pathologic response (the amount of tumor remaining when surgery is performed) in participants with breast cancer who are receiving chemotherapy prior to surgery.

Participants needed: 185
Trial details
Phase: Phase 2Age: 18+Biological sex: AllType: InterventionalSponsor: Baylor Breast Care CenterUpdated: Feb 27, 2025Locations: 2
Eligibility criteria

At least 18 years of age, and legally able to provide informed consent. Both men... [+14]

Definitive clinical or radiologic evidence of Stage IV disease [+18]

Status: Not yet recruiting

Early Changes in Metabolic Health in Breast Cancer Patients Initiating Endocrine Therapy

This clinical trial aims to investigate early metabolic health changes in early breast cancer patients that initiate antihormone therapy. Furthermore, how these changes are affected by estrogen level, treatment type, and patient characteristics. The hypothesis is, that initiation of antihormone therapy for early breast cancer patients is associated with an early deterioration in metabolic health after 3 months. This includes increased BMI (Body Mass Index), waist- and hip circumference, blood pressure, blood sugars, and lipids compared to when the patients initiate antihormone therapy. Concurrently, estradiol levels are expected to decrease. An estimated 112 patients initiating antihormone therapy at the Dept. of Oncology, Aarhus University Hospital (AUH) will be included in the study over 6 months from autumn 2024. Patients will have a metabolic screening on the day of initiating antihormone therapy and at 3-month antihormone treatment follow-up. The two metabolic screenings each consists of biometric measurements and a blood sample.

Participants needed: 112
Trial details
Age: 18+Biological sex: AllType: ObservationalSponsor: Aarhus University HospitalUpdated: Oct 2, 2024Locations: 1Duration: 3 Months
Eligibility criteria

Age ≥18 years [+3]

Pregnancy or lactation, [+1]