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OncoMatch/Breast Cancer/ESR1 (ER)

Breast CancerESR1 (ER) Clinical Trials

247 recruiting trials·Updated daily from ClinicalTrials.gov

Estrogen receptor (ER) expression defines hormone receptor-positive breast cancer — approximately 75% of cases — and determines eligibility for endocrine therapy. Acquired ESR1 mutations arise in metastatic ER+ disease after aromatase inhibitor exposure and confer resistance. Trials test selective estrogen receptor degraders (SERDs) including elacestrant (FDA-approved for ESR1-mutant disease), CDK4/6 inhibitor combinations, and novel ESR1-targeting agents.

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Top recruiting

Top recruiting ESR1 (ER) Breast Cancer trials

Ranked by phase and US site count.

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Phase 31174 US sites

Evaluating the Addition of Adjuvant Chemotherapy to Ovarian Function Suppression Plus Endocrine Therapy in Premenopausal Patients With pN0-1, ER-Positive/HER2-Negative Breast Cancer and an Oncotype Recurrence Score Less Than or Equal to 25

NRG Oncology

Phase 3809 US sites

De-Escalation of Breast Radiation Trial for Hormone Sensitive, HER-2 Negative, Oncotype Recurrence Score Less Than or Equal to 18 Breast Cancer (DEBRA)

NRG Oncology

Phase 3440 US sites

Regional Radiotherapy in Biomarker Low-Risk Node Positive and T3N0 Breast Cancer

Canadian Cancer Trials Group

Phase 3180 US sites

Study of Sacituzumab Govitecan-hziy and Pembrolizumab Versus Treatment of Physician's Choice in Patients With Triple Negative Breast Cancer Who Have Residual Invasive Disease After Surgery and Neoadjuvant Therapy (ASCENT-05/AFT-65 OptimICE-RD/GBG 119/NSABP B-63)

Gilead Sciences

Phase 3160 US sites

A Study of Elacestrant Versus Standard Endocrine Therapy in Women and Men With ER+,HER2-, Early Breast Cancer With High Risk of Recurrence

Stemline Therapeutics, Inc.

Phase 3148 US sites

An Adjuvant Endocrine-based Therapy Study of Camizestrant (AZD9833) in ER+/HER2- Early Breast Cancer (CAMBRIA-2)

AstraZeneca

Additional trials

More ESR1 (ER) Breast Cancer trials

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Phase 3
NCT05774951A Study of Camizestrant in ER+/HER2- Early Breast Cancer After at Least 2 Years of Standard Adjuvant Endocrine TherapyPhase 3131 US sitesNCT07174336A Study of Tersolisib (LY4064809/STX-478) With Other Anti-Cancer Treatments in Participants With Advanced Breast Cancer With a Genetic Change (PIK3CA)Phase 3102 US sitesNCT06072612Study of the Bria-IMT Regimen and CPI vs Physicians' Choice in Advanced Metastatic Breast Cancer.Phase 377 US sitesNCT06377852The CDK4/6 Inhibitor Dosing Knowledge (CDK) StudyPhase 366 US sitesNCT05827081Phase IIIb Study of Ribociclib + ET in Early Breast CancerPhase 363 US sitesNCT06790693A Study Evaluating the Efficacy and Safety of Inavolisib Plus CDK4/6 Inhibitor and Letrozole vs Placebo + CDK4/6i and Letrozole in Participants With Endocrine-Sensitive PIK3CA-Mutated, Hormone Receptor-Positive, HER2-Negative Advanced Breast CancerPhase 351 US sitesNCT06016738OP-1250 (Palazestrant) vs. Standard of Care for the Treatment of ER+/HER2- Advanced Breast CancerPhase 347 US sitesNCT06966700A Clinical Study of Sacituzumab Tirumotecan (Sac-TMT, MK-2870) in People With Breast Cancer (MK-2870-032)Phase 346 US sitesNCT06312176A Study of Sacituzumab Tirumotecan (MK-2870) as a Single Agent and in Combination With Pembrolizumab (MK-3475) Versus Treatment of Physician's Choice in Participants With HR+/HER2- Unresectable Locally Advanced or Metastatic Breast Cancer (MK-2870-010)Phase 346 US sitesNCT06926868A Study of Izalontamab Brengitecan Versus Chemotherapy in Participants With Previously Untreated, Locally Advanced, Recurrent Inoperable, or Metastatic Triple-negative Breast Cancer Ineligible for Anti-PD(L)1 Drugs (IZABRIGHT-Breast01)Phase 2/Phase 344 US sitesNCT05696626Evaluation of Lasofoxifene Combined With Abemaciclib Compared With Fulvestrant Combined With Abemaciclib in Locally Advanced or Metastatic ER+/HER2- Breast Cancer With an ESR1 MutationPhase 335 US sitesNCT07060807A Clinical Study of Patritumab Deruxtecan to Treat Breast Cancer (MK-1022-016)Phase 329 US sitesNCT07085767Palazestrant in Combination With Ribociclib for the First-line Treatment of ER+/HER2- Advanced Breast CancerPhase 310 US sitesNCT07205822A Study of Dato-DXd in Inoperable or Metastatic Hormone Receptor-positive, HER2 IHC 0 Breast CancerPhase 36 US sitesNCT06507618Pre-Operative Window of ET to Inform RT Decisions (POWER II)Phase 34 US sites
9 international trials (no US sites)
NCT02535221Neoadjuvant Endocrine Therapy Versus Chemotherapy in Premenopausal Patients With ER+ & HER2- Breast CancerPhase 3NCT06606730Personalizing the Use of Pembrolizumab for Patients Who Have a Strong Response in Early Triple Negative Breast CancerPhase 3NCT06781996A Study to Determine the Efficacy of a Digital Self-management Support Tool to Improve the Quality of Life During Adjuvant HOrmonal Therapy for Patients With Early Breast CancerPhase 3NCT06839001CRYoablation for Small Tumors As Local Treatment - SIX TrialPhase 3NCT05552001Safety and Efficacy Analysis of an Antibody Associated With a Chemotherapy for Patients With a Triple Negative Metastatic Breast CancerPhase 3NCT07281833Phase III Study to Evaluate the Safety, Efficacy, and Impact on Quality of Life of Capivasertib Alongside Standard-of-care Endocrine Treatment in Patients With HR+/HER2- Advanced Breast Cancer and Progression on Prior Endocrine-based TreatmentPhase 3NCT06195709ECLECTIC: EstroTEP and Circulating Biomarkers for ER-positive HER2-negative Metastatic Breast Cancer PatientsPhase 3NCT06044623Implementing Geriatric Assessment for Dose Optimization of Cyclin-dependent Kinase (CDK) 4/6-inhibitors in Older Breast Cancer PatientsPhase 3NCT05891093Efficacy and Safety of Fluzoparib Combined With Adjuvant Endocrine Therapy for HR+/HER2- SNF3-subtype Early Breast Cancer (BCTOP-L-A01)Phase 3
Other Breast Cancer biomarkers

Browse other molecular targets with active Breast Cancer trials.

HER2 (ERBB2)PGR (PR)PIK3CABRCA1BRCA2
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