Medical Information Only. Consult your healthcare provider before considering clinical trial enrollment.

ClinicalTrials.gov 423 recruiting now early-phase tilt #1 of 28,963 conditions

Breast Cancer: early-phase trial registry

423 of 1,251 indexed Breast Cancer trials are currently recruiting, with more weight in Phase 1-2.

Corpus placement: #1 of 28,963 conditions by registered trial count.

1,251 US clinical trials · 423 currently recruiting · #1 of 28,963 conditions by registered trial count

Breast Cancer: 1,251 US clinical trials tracked, 423 recruiting.

Breast Cancer is the subject of 1,251 registered US clinical trials on ClinicalTrials.gov, 423 of them currently open to new participants. 120 are in Phase 3-4 (later-stage) and 491 in Phase 1-2 (earlier-stage). The most active sponsor is Memorial Sloan Kettering Cancer Center, running 98 of these trials.

Open enrollment, early-phase tilt

Breast Cancer has 1,251 registered US clinical trials, 423 of them open to new participants right now, about 34% of the total.

423
recruiting participants now
34%
of trials open to enrollment
120
in Phase 3-4 (later-stage)
98
top sponsor: Memorial Sloan Kettering Cancer Center

Corpus placement: #1 of 28,963 conditions by registered trial count on ClinicalTrials.gov-derived indexes. Registry reference only, not medical advice.

Key findings

What ClinicalTrials.gov does not surface for Breast Cancer on its own pages , computed from the registry mirror as of 2026-07-11. Each line carries its own denominator so it can be quoted as it stands.

  1. Breast Cancer is recruiting below its size-band peers.

    423 of 1,251 indexed trials (33.8%) are open to enrollment, against a 37.2% average across 135 conditions with 100+ trials. The peer set uses the same ClinicalTrials.gov-derived counts as this page.

  2. Sponsorship of Breast Cancer trials is spread across many organizations.

    Memorial Sloan Kettering Cancer Center accounts for 98 of 1,251 trials (7.8%). 367 distinct sponsors appear on at least one study for this condition label.

  3. Typical Breast Cancer enrolment sits around 90 participants.

    Median target enrolment is 90 among the 1,225 trials that report a genuine target (sentinel values excluded). 630 of those (51.4%) plan for fewer than 100 participants.

  4. Breast Cancer research is mostly interventional.

    1,015 interventional and 236 observational studies make up this index (81.1% interventional). Study type is sponsor-reported on ClinicalTrials.gov.

Phase 1235Phase 2256Phase 3100Phase 420

Open and recent trials

1,251 total, page 11 of 26

ACTIVE NOT RECRUITING 269 participants

Non-contrast DWI for Supplemental Screening

University of Washington

NCT03607552

ACTIVE NOT RECRUITING NA 265 participants

Intraoperative Radiation Therapy (IORT) in DCIS

Columbia University

NCT03216421

ACTIVE NOT RECRUITING 264 participants

Abbreviated Breast MRI (AB-MRI) With Golden-angle Radial Compressed-sensing and Parallel Imaging (GRASP)

NYU Langone Health

NCT03927768

ACTIVE NOT RECRUITING Phase 1 255 participants

Study of LEE011, BYL719 and Letrozole in Advanced ER+ Breast Cancer

Novartis Pharmaceuticals

NCT01872260

ACTIVE NOT RECRUITING 253 participants

Long-Term Follow-Up in Women With Early Breast Cancer Three Years of More Post Primary Treatment

UNC Lineberger Comprehensive Cancer Center

NCT05926024

ACTIVE NOT RECRUITING 253 participants

Elevate! : An Elderly Breast Cancer Cohort Study

Dana-Farber Cancer Institute

NCT03818087

ACTIVE NOT RECRUITING 252 participants

Attention and Interpretation Modification (AIM) for Fear of Cancer Recurrence: An Intervention Development Study

Memorial Sloan Kettering Cancer Center

NCT01517945

ACTIVE NOT RECRUITING Phase 3 250 participants

Ovarian Suppression Evaluating Subcutaneous Leuprolide Acetate in Breast Cancer

Tolmar

NCT04906395

ACTIVE NOT RECRUITING NA 250 participants

Writing Interventions in Breast Cancer Patients Taking Aromatase Inhibitors

Carnegie Mellon University

NCT04651452

ACTIVE NOT RECRUITING 238 participants

Longitudinal Impact of Adjuvant Chemotherapy on Functional Status, Comorbidity and Quality of Life

City of Hope Medical Center

NCT01030250

ACTIVE NOT RECRUITING 229 participants

Monitoring Plasma Tumor DNA in Early-Stage Breast Cancer

Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins

NCT02743910

ACTIVE NOT RECRUITING 220 participants

Evaluation And Risk Assessment For Persistent Postsurgical Pain After Breast Surgery

KK Women's and Children's Hospital

NCT03408717

ACTIVE NOT RECRUITING Phase 2 220 participants

Proton Radiation for Stage II/III Breast Cancer

Proton Collaborative Group

NCT01758445

ACTIVE NOT RECRUITING Phase 1 217 participants

A Phase 1/2 Trial of ARV-471 Alone and in Combination With Palbociclib (IBRANCE®) in Patients With ER+/HER2- Locally Advanced or Metastatic Breast Cancer

Arvinas Estrogen Receptor

NCT04072952

ACTIVE NOT RECRUITING 217 participants

Circulating Tumor DNA and Immunophenotyping as Potential Biomarkers With Regional Nodal Irradiation for Breast Cancer

Mayo Clinic

NCT04308720

ACTIVE NOT RECRUITING NA 205 participants

Feasibility Study: IGNITE-TX (Identifying Individuals for Genetic Testing & Treatment) Intervention

M.D. Anderson Cancer Center

NCT05677048

ACTIVE NOT RECRUITING NA 204 participants

Robotic vs. Open NSM for Early Stage Breast Cancer

Intuitive Surgical

NCT05720039

ACTIVE NOT RECRUITING NA 203 participants

Interventional Program Educates, Identifies + Overcomes Barriers to Complete Screening Mammography

Case Comprehensive Cancer Center

NCT04348123

ACTIVE NOT RECRUITING Phase 2 200 participants

Radiation Therapy in Treating Women With Early Stage Breast Cancer

Rutgers, The State University of New Jersey

NCT00909909

ACTIVE NOT RECRUITING 200 participants

Mechanisms, Predictors, and Social Determinants of Cardiotoxicity in Breast Cancer

Abramson Cancer Center at Penn Medicine

NCT05078190

ACTIVE NOT RECRUITING Phase 1 200 participants

To Evaluate the Safety, Tolerability, and Pharmacokinetics of Inavolisib Single Agent in Participants With Solid Tumors and in Combination With Endocrine and Targeted Therapies in Participants With Breast Cancer

Genentech

NCT03006172

ACTIVE NOT RECRUITING NA 200 participants

Safety and Efficacy of Omission of Sentinel Node Biopsy in Patients With Estrogen-Positive Breast Cancer Over Age 65

Cedars-Sinai Medical Center

NCT02564848

ACTIVE NOT RECRUITING NA 200 participants

Nature Sounds as a Pain and Anxiety Reducing Strategy in Patients Undergoing Breast Core Biopsy

University of Chicago

NCT03238976

ACTIVE NOT RECRUITING NA 196 participants

Evaluating the Use of Patient Navigation to Promote Timely Diagnostic Evaluation During the COVID-19 Pandemic

Johns Hopkins University

NCT05181722

ACTIVE NOT RECRUITING Phase 2 195 participants

Palbociclib and Endocrine Therapy for LObular Breast Cancer Preoperative Study (PELOPS)

Dana-Farber Cancer Institute

NCT02764541

ACTIVE NOT RECRUITING Phase 1 193 participants

A Study of LOXO-783 in Patients With Breast Cancer/Other Solid Tumors

Eli Lilly and Company

NCT05307705

ACTIVE NOT RECRUITING Phase 1 192 participants

A Study to Learn About the Study Medicine (Called PF-07220060 in Combination With PF-07104091) In Participants With Breast Cancer and Solid Tumors

Pfizer

NCT05262400

ACTIVE NOT RECRUITING 190 participants

A Study of Limited Heart Monitoring During Non-anthracycline Trastuzumab-based Therapy in Breast Cancer Patients

Memorial Sloan Kettering Cancer Center

NCT03983382

ACTIVE NOT RECRUITING NA 190 participants

Gradient-Echo Spectroscopic Imaging Study of Saturated Fat and Breast Cancer

NYU Langone Health

NCT03400215

ACTIVE NOT RECRUITING 187 participants

Assessment of Sensory Gating, Attention, and Executive Control in Breast Cancer

Memorial Sloan Kettering Cancer Center

NCT03619083

ACTIVE NOT RECRUITING Phase 1 186 participants

T-Cell Therapy for Advanced Breast Cancer

Memorial Sloan Kettering Cancer Center

NCT02792114

ACTIVE NOT RECRUITING Phase 3 185 participants

Roll Over StudY for Patients Who Have Completed a Previous Oncology Study With Olaparib

AstraZeneca

NCT04421963

ACTIVE NOT RECRUITING Phase 2 184 participants

Treating Breast Cancer Patients Undergoing Trastuzumab Treatment With Carvedilol to Reduce Incidence of Heart Failure

Mayo Clinic

NCT03879629

ACTIVE NOT RECRUITING Phase 1 181 participants

A Study of GDC-9545 Alone or in Combination With Palbociclib and/or Luteinizing Hormone-Releasing Hormone (LHRH) Agonist in Locally Advanced or Metastatic Estrogen Receptor-Positive Breast Cancer

Genentech

NCT03332797

ACTIVE NOT RECRUITING Phase 1 180 participants

P-MUC1C-ALLO1 Allogeneic CAR-T Cells in the Treatment of Subjects With Advanced or Metastatic Solid Tumors

Poseida Therapeutics

NCT05239143

ACTIVE NOT RECRUITING Phase 1 179 participants

Study of NGM707 As Monotherapy and in Combination with Pembrolizumab in Advanced or Metastatic Solid Tumor Malignancies

NGM Biopharmaceuticals

NCT04913337

ACTIVE NOT RECRUITING Phase 2 178 participants

Phase II Study of Neoadjuvant ArOMatase Inhibitor Therapy for ER+ Breast Cancer (NAOMI)

Dartmouth-Hitchcock Medical Center

NCT04568616

ACTIVE NOT RECRUITING Phase 2 174 participants

MARGetuximab Or Trastuzumab (MARGOT)

Dana-Farber Cancer Institute

NCT04425018

ACTIVE NOT RECRUITING NA 165 participants

Exercise Post-Diagnosis of Breast Cancer

University of Hawaii

NCT04013568

ACTIVE NOT RECRUITING 164 participants

Evaluating the Effects of Genetic Testing on Patients' Stress Levels

Medical College of Wisconsin

NCT02783664

ACTIVE NOT RECRUITING Phase 2 164 participants

T-DM1+Pertuzumab in Pre-OP Early-Stage HER2+ BRCA

Dana-Farber Cancer Institute

NCT02326974

ACTIVE NOT RECRUITING NA 162 participants

Sentinel Lymph Node Biopsy After Neoadjuvant Chemotherapy For Locally Advanced Breast Cancer

Memorial Sloan Kettering Cancer Center

NCT03255577

ACTIVE NOT RECRUITING NA 160 participants

Reducing Metabolic Dysregulation in Obese Latina Breast Cancer Survivors Using Physical Activity

Dana-Farber Cancer Institute

NCT04717050

ACTIVE NOT RECRUITING Phase 2 154 participants

PF-07104091 as a Single Agent and in Combination Therapy

Pfizer

NCT04553133

ACTIVE NOT RECRUITING NA 150 participants

Partial Breast Proton Therapy for Early Stage Breast Cancer

Loma Linda University

NCT01310530

ACTIVE NOT RECRUITING 150 participants

Achieving Equity in Genomic Testing for Breast Cancer Through Partner-Led Strategies and Policies

Stanford University

NCT05916378

ACTIVE NOT RECRUITING NA 146 participants

A Randomised Controlled Trial to Evaluate the Impact of Complement Theory's Live CoActive Exercise Coaching and Personalized Digital Application on Cancer Survivors' Quality of Life

Complement Theory

NCT06397651

ACTIVE NOT RECRUITING NA 145 participants

Peer Navigator Education in Improving Survivorship Care in African American Breast Cancer Survivors

City of Hope Medical Center

NCT01450020

ACTIVE NOT RECRUITING NA 144 participants

Supervised Aerobic Training During or After Chemotherapy for Operable Breast Cancer

Memorial Sloan Kettering Cancer Center

NCT01943695

ACTIVE NOT RECRUITING Phase 1 140 participants

A Phase I, Open-Label, Multi-center Study to Assess the Safety, Tolerability and Pharmacokinetics of AZD6244 (ARRY-142886)

AstraZeneca

NCT00600496

← Previous Page 11 of 26 Next →

Phase Distribution

PhaseTrial count
Phase 1 235
Phase 2 256
Phase 3 100
Phase 4 20

Source: ClinicalTrials.gov, National Library of Medicine. Data is informational only.

What is open for Breast Cancer right now

423 recruiting of 1,251 indexed (34% open).

Phase mix: 120 late (III/IV) vs 491 early (I/II) (early-phase heavy).

Top sponsor: Memorial Sloan Kettering Cancer Center (98 trials), 9 others listed. 50 shown below, recruiting first. #1 of 28,963 conditions by registered trial count.

How open-enrollment share is computed

Open share is recruiting_count divided by trial_count for this condition label in the public registry export. Status can change between pulls; treat the figure as a snapshot of research attention, not treatment availability.

Frequently Asked Questions

How many clinical trials are there for Breast Cancer?

PlainTrial tracks 1,251 US clinical trials for Breast Cancer, of which 423 are currently recruiting participants. Data sourced from ClinicalTrials.gov.

How do I find a recruiting trial for Breast Cancer?

Use the trial list above filtered by "Recruiting" status, or visit our trial finder at /recruiting to search by condition and state. Always discuss trial participation with your healthcare provider before enrolling.

Is this data current?

Data is sourced from ClinicalTrials.gov and reflects our most recent data pull. Trial status may have changed since then. Always verify current information at ClinicalTrials.gov before making decisions about participation.

Disclaimer: This information is provided for informational purposes only and does not constitute professional advice. Data is sourced from ClinicalTrials.gov (National Library of Medicine). Consult a qualified professional before making decisions based on this data.

Source: ClinicalTrials.gov (NIH/NLM) ClinicalTrials.gov AACT registry · 2026 Trial counts and statuses sourced from ClinicalTrials.gov. Sponsor counts include both industry and federal/academic sponsors.

Verify with NIH →

Every figure on PlainTrial is rendered directly from the ClinicalTrials.gov registry, no number is typed in by an editor. This page aggregates every registered trial for this condition, live from the dataset. See our editorial standards & corrections policy, the methodology behind these numbers, the data changelog, or report a data error.