{
  "api_version": "1",
  "request": {
    "url": "https://clinicaltrialsfind.com/api/v1/search.json?condition=Early+Stage+Estrogen+Receptor+%28ER%29+Positive+Breast+Cancer&page=2",
    "query": {
      "condition": "Early Stage Estrogen Receptor (ER) Positive Breast Cancer",
      "page": 2
    },
    "page_size": 10
  },
  "pagination": {
    "page": 2,
    "page_size": 10,
    "total_count": 10,
    "total_pages": 1,
    "next_page_url": null,
    "previous_page_url": "https://clinicaltrialsfind.com/api/v1/search.json?condition=Early+Stage+Estrogen+Receptor+%28ER%29+Positive+Breast+Cancer&page=1&page_size=10"
  },
  "source": "remote",
  "last_synced_at": "2026-07-22T02:23:01.831Z",
  "attribution": "Data derived from public ClinicalTrials.gov records. The official record at https://clinicaltrials.gov/ remains the source of truth for current availability, contacts, and full study details.",
  "notes": [
    "This endpoint exposes only public summary fields — no participant contact emails, phone numbers, or scraped investigator contact details.",
    "For contact information and full protocol detail, follow each trial's `official_url` to the ClinicalTrials.gov record.",
    "This API is a navigational aid. It does not provide medical advice, eligibility determinations, or compensation guarantees."
  ],
  "trials": [
    {
      "nct_id": "NCT00093002",
      "title": "Fulvestrant (FASLODEX™) as a Treatment in Postmenopausal Women With Estrogen Receptor Positive Breast Cancer",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE2"
      ],
      "conditions": [
        "Breast Cancer"
      ],
      "interventions": [
        {
          "name": "Fulvestrant",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "AstraZeneca",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": null,
        "maximum_age": null,
        "sex": "FEMALE",
        "summary": "Female only"
      },
      "enrollment_count": 179,
      "start_date": "2004-06",
      "completion_date": "2007-07",
      "has_results": false,
      "last_update_posted_date": "2008-06-12",
      "last_synced_at": "2026-07-22T02:23:01.831Z",
      "location_count": 7,
      "location_summary": "Little Rock, Arkansas • Boston, Massachusetts • Winchester, Massachusetts + 4 more",
      "locations": [
        {
          "city": "Little Rock",
          "state": "Arkansas"
        },
        {
          "city": "Boston",
          "state": "Massachusetts"
        },
        {
          "city": "Winchester",
          "state": "Massachusetts"
        },
        {
          "city": "Albuquerque",
          "state": "New Mexico"
        },
        {
          "city": "Hershey",
          "state": "Pennsylvania"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT00093002"
    },
    {
      "nct_id": "NCT00755313",
      "title": "Effects of Chemotherapy on the Brain in Women With Newly Diagnosed Early-Stage Breast Cancer",
      "overall_status": "COMPLETED",
      "study_type": "OBSERVATIONAL",
      "phases": [],
      "conditions": [
        "Breast Cancer",
        "Chemotherapeutic Agent Toxicity",
        "Cognitive/Functional Effects",
        "Fatigue",
        "Long-term Effects Secondary to Cancer Therapy in Adults",
        "Neurotoxicity",
        "Psychosocial Effects of Cancer and Its Treatment"
      ],
      "interventions": [
        {
          "name": "trastuzumab",
          "type": "BIOLOGICAL"
        },
        {
          "name": "aromatase inhibition therapy",
          "type": "DRUG"
        },
        {
          "name": "carboplatin",
          "type": "DRUG"
        },
        {
          "name": "cyclophosphamide",
          "type": "DRUG"
        },
        {
          "name": "docetaxel",
          "type": "DRUG"
        },
        {
          "name": "doxorubicin hydrochloride",
          "type": "DRUG"
        },
        {
          "name": "metabolic assessment",
          "type": "OTHER"
        },
        {
          "name": "questionnaire administration",
          "type": "OTHER"
        },
        {
          "name": "study of socioeconomic and demographic variables",
          "type": "OTHER"
        },
        {
          "name": "cognitive assessment",
          "type": "PROCEDURE"
        },
        {
          "name": "positron emission tomography",
          "type": "PROCEDURE"
        },
        {
          "name": "fludeoxyglucose F 18",
          "type": "RADIATION"
        }
      ],
      "intervention_types": [
        "BIOLOGICAL",
        "DRUG",
        "OTHER",
        "PROCEDURE",
        "RADIATION"
      ],
      "sponsor": "University of California, San Francisco",
      "sponsor_class": "OTHER",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "35 Years",
        "maximum_age": "80 Years",
        "sex": "FEMALE",
        "summary": "35 Years to 80 Years · Female only"
      },
      "enrollment_count": 81,
      "start_date": "2007-05",
      "completion_date": "2014-06-06",
      "has_results": false,
      "last_update_posted_date": "2017-11-24",
      "last_synced_at": "2026-07-22T02:23:01.831Z",
      "location_count": 1,
      "location_summary": "San Francisco, California",
      "locations": [
        {
          "city": "San Francisco",
          "state": "California"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT00755313"
    },
    {
      "nct_id": "NCT03725059",
      "title": "Study of Pembrolizumab (MK-3475) Versus Placebo in Combination With Neoadjuvant Chemotherapy & Adjuvant Endocrine Therapy in the Treatment of Early-Stage Estrogen Receptor-Positive, Human Epidermal Growth Factor Receptor 2-Negative (ER+/HER2-) Breast Cancer (MK-3475-756/KEYNOTE-756)",
      "overall_status": "ACTIVE_NOT_RECRUITING",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE3"
      ],
      "conditions": [
        "Breast Cancer"
      ],
      "interventions": [
        {
          "name": "Pembrolizumab (K)",
          "type": "BIOLOGICAL"
        },
        {
          "name": "Placebo (P)",
          "type": "DRUG"
        },
        {
          "name": "Paclitaxel (X)",
          "type": "DRUG"
        },
        {
          "name": "Doxorubicin (A)",
          "type": "DRUG"
        },
        {
          "name": "Epirubicin (E)",
          "type": "DRUG"
        },
        {
          "name": "Cyclophosphamide (C)",
          "type": "DRUG"
        },
        {
          "name": "Endocrine therapy",
          "type": "DRUG"
        },
        {
          "name": "Radiation therapy",
          "type": "RADIATION"
        },
        {
          "name": "Surgery",
          "type": "PROCEDURE"
        }
      ],
      "intervention_types": [
        "BIOLOGICAL",
        "DRUG",
        "RADIATION",
        "PROCEDURE"
      ],
      "sponsor": "Merck Sharp & Dohme LLC",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "18 Years and older"
      },
      "enrollment_count": 1240,
      "start_date": "2018-12-27",
      "completion_date": "2031-01-24",
      "has_results": false,
      "last_update_posted_date": "2025-07-11",
      "last_synced_at": "2026-07-22T02:23:01.831Z",
      "location_count": 45,
      "location_summary": "Daphne, Alabama • Goodyear, Arizona • Tucson, Arizona + 39 more",
      "locations": [
        {
          "city": "Daphne",
          "state": "Alabama"
        },
        {
          "city": "Goodyear",
          "state": "Arizona"
        },
        {
          "city": "Tucson",
          "state": "Arizona"
        },
        {
          "city": "Los Angeles",
          "state": "California"
        },
        {
          "city": "Mountain View",
          "state": "California"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT03725059"
    },
    {
      "nct_id": "NCT01439282",
      "title": "Eribulin in Combination With Capecitabine for Adjuvant Treatment in Estrogen Receptor-Positive Early Stage Breast Cancer",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE2"
      ],
      "conditions": [
        "Estrogen Receptor Positive Tumor",
        "Breast Cancer"
      ],
      "interventions": [
        {
          "name": "eribulin mesylate",
          "type": "DRUG"
        },
        {
          "name": "capecitabine",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "Eisai Inc.",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "18 Years and older"
      },
      "enrollment_count": 77,
      "start_date": "2011-08",
      "completion_date": "2014-05",
      "has_results": true,
      "last_update_posted_date": "2023-06-22",
      "last_synced_at": "2026-07-22T02:23:01.831Z",
      "location_count": 23,
      "location_summary": "Tucson, Arizona • Orlando, Florida • Marietta, Georgia + 16 more",
      "locations": [
        {
          "city": "Tucson",
          "state": "Arizona"
        },
        {
          "city": "Tucson",
          "state": "Arizona"
        },
        {
          "city": "Orlando",
          "state": "Florida"
        },
        {
          "city": "Marietta",
          "state": "Georgia"
        },
        {
          "city": "Albany",
          "state": "New York"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT01439282"
    },
    {
      "nct_id": "NCT02057029",
      "title": "Assessment of the Decision-making Impact of the Breast Cancer Index in Recommending Extended Adjuvant Endocrine Therapy for Patients With Early Stage ER-positive Breast Cancer",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "NA"
      ],
      "conditions": [
        "Breast Cancer",
        "Early Stage Estrogen Receptor (ER) Positive Breast Cancer"
      ],
      "interventions": [
        {
          "name": "BCI Assay Results",
          "type": "BEHAVIORAL"
        }
      ],
      "intervention_types": [
        "BEHAVIORAL"
      ],
      "sponsor": "Yale University",
      "sponsor_class": "OTHER",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": null,
        "maximum_age": null,
        "sex": "FEMALE",
        "summary": "Female only"
      },
      "enrollment_count": 96,
      "start_date": "2014-01",
      "completion_date": "2015-06",
      "has_results": false,
      "last_update_posted_date": "2016-01-08",
      "last_synced_at": "2026-07-22T02:23:01.831Z",
      "location_count": 1,
      "location_summary": "New Haven, Connecticut",
      "locations": [
        {
          "city": "New Haven",
          "state": "Connecticut"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT02057029"
    },
    {
      "nct_id": "NCT03719495",
      "title": "Evaluation of Endocrine Therapy Effects of Host Immunity in Early Stage Breast Cancer",
      "overall_status": "COMPLETED",
      "study_type": "OBSERVATIONAL",
      "phases": [],
      "conditions": [
        "Breast Cancer",
        "Estrogen Receptor-positive Breast Cancer",
        "Healthy"
      ],
      "interventions": [],
      "intervention_types": [],
      "sponsor": "Duke University",
      "sponsor_class": "OTHER",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": "75 Years",
        "sex": "FEMALE",
        "summary": "18 Years to 75 Years · Female only"
      },
      "enrollment_count": 68,
      "start_date": "2019-06-19",
      "completion_date": "2023-07-31",
      "has_results": false,
      "last_update_posted_date": "2024-05-16",
      "last_synced_at": "2026-07-22T02:23:01.831Z",
      "location_count": 1,
      "location_summary": "Durham, North Carolina",
      "locations": [
        {
          "city": "Durham",
          "state": "North Carolina"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT03719495"
    },
    {
      "nct_id": "NCT01349322",
      "title": "Higher Per Daily Treatment-Dose Radiation Therapy or Standard Per Daily Treatment Radiation Therapy in Treating Patients With Early-Stage Breast Cancer That Was Removed by Surgery",
      "overall_status": "ACTIVE_NOT_RECRUITING",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE3"
      ],
      "conditions": [
        "Breast Cancer"
      ],
      "interventions": [
        {
          "name": "Standard fractionation whole breast irradiation",
          "type": "RADIATION"
        },
        {
          "name": "Hypofractionated whole breast irradiation",
          "type": "RADIATION"
        },
        {
          "name": "Concurrent boost",
          "type": "RADIATION"
        },
        {
          "name": "Sequential boost",
          "type": "RADIATION"
        }
      ],
      "intervention_types": [
        "RADIATION"
      ],
      "sponsor": "Radiation Therapy Oncology Group",
      "sponsor_class": "NETWORK",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": null,
        "sex": "FEMALE",
        "summary": "18 Years and older · Female only"
      },
      "enrollment_count": 2354,
      "start_date": "2011-05-24",
      "completion_date": null,
      "has_results": true,
      "last_update_posted_date": "2026-03-05",
      "last_synced_at": "2026-07-22T02:23:01.831Z",
      "location_count": 386,
      "location_summary": "Birmingham, Alabama • Scottsdale, Arizona • Tucson, Arizona + 304 more",
      "locations": [
        {
          "city": "Birmingham",
          "state": "Alabama"
        },
        {
          "city": "Birmingham",
          "state": "Alabama"
        },
        {
          "city": "Scottsdale",
          "state": "Arizona"
        },
        {
          "city": "Scottsdale",
          "state": "Arizona"
        },
        {
          "city": "Tucson",
          "state": "Arizona"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT01349322"
    },
    {
      "nct_id": "NCT02526498",
      "title": "Accelerated Partial Breast Radiation Therapy Using High-Dose Rate Brachytherapy in Treating Patients With Early Stage Breast Cancer After Surgery",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE2"
      ],
      "conditions": [
        "Ductal Breast Carcinoma In Situ",
        "Estrogen Receptor Positive",
        "Invasive Breast Carcinoma",
        "Progesterone Receptor Positive",
        "Stage IA Breast Cancer",
        "Stage IB Breast Cancer",
        "Stage IIA Breast Cancer"
      ],
      "interventions": [
        {
          "name": "Accelerated Partial Breast Irradiation",
          "type": "RADIATION"
        },
        {
          "name": "High-Dose Rate Brachytherapy",
          "type": "RADIATION"
        },
        {
          "name": "Questionnaire Administration",
          "type": "OTHER"
        }
      ],
      "intervention_types": [
        "RADIATION",
        "OTHER"
      ],
      "sponsor": "Rutgers, The State University of New Jersey",
      "sponsor_class": "OTHER",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "45 Years",
        "maximum_age": null,
        "sex": "FEMALE",
        "summary": "45 Years and older · Female only"
      },
      "enrollment_count": 200,
      "start_date": "2015-07-15",
      "completion_date": "2021-03-31",
      "has_results": true,
      "last_update_posted_date": "2023-05-15",
      "last_synced_at": "2026-07-22T02:23:01.831Z",
      "location_count": 10,
      "location_summary": "Gilbert, Arizona • La Jolla, California • Royal Oak, Michigan + 6 more",
      "locations": [
        {
          "city": "Gilbert",
          "state": "Arizona"
        },
        {
          "city": "La Jolla",
          "state": "California"
        },
        {
          "city": "Royal Oak",
          "state": "Michigan"
        },
        {
          "city": "New Brunswick",
          "state": "New Jersey"
        },
        {
          "city": "New Brunswick",
          "state": "New Jersey"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT02526498"
    },
    {
      "nct_id": "NCT04961996",
      "title": "A Study Evaluating the Efficacy and Safety of Adjuvant Giredestrant Compared With Physician's Choice of Adjuvant Endocrine Monotherapy in Participants With Estrogen Receptor-Positive, HER2-Negative Early Breast Cancer (lidERA Breast Cancer)",
      "overall_status": "ACTIVE_NOT_RECRUITING",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE3"
      ],
      "conditions": [
        "Early Breast Cancer"
      ],
      "interventions": [
        {
          "name": "Giredestrant",
          "type": "DRUG"
        },
        {
          "name": "Physician's Choice of Endocrine Therapy",
          "type": "DRUG"
        },
        {
          "name": "LHRH Agonist",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "Hoffmann-La Roche",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "18 Years and older"
      },
      "enrollment_count": 4170,
      "start_date": "2021-08-27",
      "completion_date": "2033-09-30",
      "has_results": false,
      "last_update_posted_date": "2026-06-17",
      "last_synced_at": "2026-07-22T02:23:01.831Z",
      "location_count": 72,
      "location_summary": "Daphne, Alabama • Bakersfield, California • Fullerton, California + 66 more",
      "locations": [
        {
          "city": "Daphne",
          "state": "Alabama"
        },
        {
          "city": "Bakersfield",
          "state": "California"
        },
        {
          "city": "Fullerton",
          "state": "California"
        },
        {
          "city": "Long Beach",
          "state": "California"
        },
        {
          "city": "Los Alamitos",
          "state": "California"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT04961996"
    },
    {
      "nct_id": "NCT06492616",
      "title": "A Study of Elacestrant Versus Standard Endocrine Therapy in Women and Men With ER+,HER2-, Early Breast Cancer With High Risk of Recurrence",
      "overall_status": "RECRUITING",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE3"
      ],
      "conditions": [
        "Breast Cancer"
      ],
      "interventions": [
        {
          "name": "Elacestrant",
          "type": "DRUG"
        },
        {
          "name": "Anastrozole",
          "type": "DRUG"
        },
        {
          "name": "Letrozole",
          "type": "DRUG"
        },
        {
          "name": "Exemestane",
          "type": "DRUG"
        },
        {
          "name": "Tamoxifen",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "Stemline Therapeutics, Inc.",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "18 Years and older"
      },
      "enrollment_count": 4220,
      "start_date": "2024-09-27",
      "completion_date": "2032-10",
      "has_results": false,
      "last_update_posted_date": "2026-07-08",
      "last_synced_at": "2026-07-22T02:23:01.831Z",
      "location_count": 170,
      "location_summary": "Daphne, Alabama • Chandler, Arizona • Gilbert, Arizona + 134 more",
      "locations": [
        {
          "city": "Daphne",
          "state": "Alabama"
        },
        {
          "city": "Chandler",
          "state": "Arizona"
        },
        {
          "city": "Gilbert",
          "state": "Arizona"
        },
        {
          "city": "Scottsdale",
          "state": "Arizona"
        },
        {
          "city": "Tucson",
          "state": "Arizona"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT06492616"
    }
  ]
}