{
  "api_version": "1",
  "request": {
    "url": "https://clinicaltrialsfind.com/api/v1/search.json?condition=Early+Stage+Estrogen+Receptor+%28ER%29+Positive+Breast+Cancer",
    "query": {
      "condition": "Early Stage Estrogen Receptor (ER) Positive Breast Cancer"
    },
    "page_size": 10
  },
  "pagination": {
    "page": 1,
    "page_size": 10,
    "total_count": 35,
    "total_pages": 4,
    "next_page_url": "https://clinicaltrialsfind.com/api/v1/search.json?condition=Early+Stage+Estrogen+Receptor+%28ER%29+Positive+Breast+Cancer&page=2&page_size=10",
    "previous_page_url": null
  },
  "source": "remote",
  "last_synced_at": "2026-07-22T00:08:01.997Z",
  "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": "NCT04436744",
      "title": "A Study to Evaluate the Efficacy, Safety, and Pharmacokinetics of Giredestrant Plus Palbociclib Compared With Anastrozole Plus Palbociclib for Postmenopausal Women With Estrogen Receptor-Positive and HER2-Negative Untreated Early Breast Cancer (coopERA Breast Cancer)",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE2"
      ],
      "conditions": [
        "Early Breast Cancer"
      ],
      "interventions": [
        {
          "name": "Giredestrant",
          "type": "DRUG"
        },
        {
          "name": "Anastrozole",
          "type": "DRUG"
        },
        {
          "name": "Palbociclib",
          "type": "DRUG"
        },
        {
          "name": "Surgery",
          "type": "PROCEDURE"
        }
      ],
      "intervention_types": [
        "DRUG",
        "PROCEDURE"
      ],
      "sponsor": "Hoffmann-La Roche",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": null,
        "sex": "FEMALE",
        "summary": "18 Years and older · Female only"
      },
      "enrollment_count": 221,
      "start_date": "2020-09-04",
      "completion_date": "2021-11-24",
      "has_results": true,
      "last_update_posted_date": "2023-02-02",
      "last_synced_at": "2026-07-22T00:08:01.997Z",
      "location_count": 10,
      "location_summary": "Burbank, California • Laguna Hills, California • San Luis Obispo, California + 7 more",
      "locations": [
        {
          "city": "Burbank",
          "state": "California"
        },
        {
          "city": "Laguna Hills",
          "state": "California"
        },
        {
          "city": "San Luis Obispo",
          "state": "California"
        },
        {
          "city": "Santa Monica",
          "state": "California"
        },
        {
          "city": "Torrance",
          "state": "California"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT04436744"
    },
    {
      "nct_id": "NCT07287098",
      "title": "A Study of Imlunestrant (LY3484356) in Premenopausal Women With Estrogen Receptor-Positive (ER+) Human Epidermal Growth Factor Receptor 2 Negative (HER2-) Early Breast Cancer",
      "overall_status": "RECRUITING",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE2"
      ],
      "conditions": [
        "Breast Neoplasms"
      ],
      "interventions": [
        {
          "name": "Imlunestrant",
          "type": "DRUG"
        },
        {
          "name": "Goserelin",
          "type": "DRUG"
        },
        {
          "name": "Tamoxifen 20 mg",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "Eli Lilly and Company",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": null,
        "sex": "FEMALE",
        "summary": "18 Years and older · Female only"
      },
      "enrollment_count": 600,
      "start_date": "2026-05-13",
      "completion_date": "2029-12",
      "has_results": false,
      "last_update_posted_date": "2026-07-17",
      "last_synced_at": "2026-07-22T00:08:01.997Z",
      "location_count": 29,
      "location_summary": "Birmingham, Alabama • Chandler, Arizona • Los Angeles, California + 23 more",
      "locations": [
        {
          "city": "Birmingham",
          "state": "Alabama"
        },
        {
          "city": "Chandler",
          "state": "Arizona"
        },
        {
          "city": "Los Angeles",
          "state": "California"
        },
        {
          "city": "Santa Monica",
          "state": "California"
        },
        {
          "city": "Greeley",
          "state": "Colorado"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT07287098"
    },
    {
      "nct_id": "NCT01385137",
      "title": "S0927:Omega3-Fatty Acid Supp in Treating Muscle&Bone Pain&Stiffness in Pts W/Stg I,II,III Brst Canc Rec'v Hormone Thpy",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE3"
      ],
      "conditions": [
        "Arthralgia",
        "Breast Cancer",
        "Pain"
      ],
      "interventions": [
        {
          "name": "omega-3 fatty acid",
          "type": "DIETARY_SUPPLEMENT"
        },
        {
          "name": "placebo",
          "type": "OTHER"
        }
      ],
      "intervention_types": [
        "DIETARY_SUPPLEMENT",
        "OTHER"
      ],
      "sponsor": "SWOG Cancer Research Network",
      "sponsor_class": "NETWORK",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": "120 Years",
        "sex": "FEMALE",
        "summary": "18 Years to 120 Years · Female only"
      },
      "enrollment_count": 262,
      "start_date": "2012-02",
      "completion_date": "2014-03",
      "has_results": true,
      "last_update_posted_date": "2017-04-07",
      "last_synced_at": "2026-07-22T00:08:01.997Z",
      "location_count": 292,
      "location_summary": "Mobile, Alabama • Anchorage, Alaska • Fairbanks, Alaska + 215 more",
      "locations": [
        {
          "city": "Mobile",
          "state": "Alabama"
        },
        {
          "city": "Anchorage",
          "state": "Alaska"
        },
        {
          "city": "Fairbanks",
          "state": "Alaska"
        },
        {
          "city": "Little Rock",
          "state": "Arkansas"
        },
        {
          "city": "Rogers",
          "state": "Arkansas"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT01385137"
    },
    {
      "nct_id": "NCT02625935",
      "title": "Prospective Observational Study Evaluating Treatment Decision Impact of Prosigna® in Early Stage Breast Cancer Patients",
      "overall_status": "COMPLETED",
      "study_type": "OBSERVATIONAL",
      "phases": [],
      "conditions": [
        "Breast Cancer"
      ],
      "interventions": [],
      "intervention_types": [],
      "sponsor": "NanoString Technologies, Inc.",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": null,
        "maximum_age": null,
        "sex": "FEMALE",
        "summary": "Female only"
      },
      "enrollment_count": 206,
      "start_date": "2015-12",
      "completion_date": "2017-10-10",
      "has_results": false,
      "last_update_posted_date": "2017-10-13",
      "last_synced_at": "2026-07-22T00:08:01.997Z",
      "location_count": 4,
      "location_summary": "Fort Myers, Florida • Scarborough, Maine • Bethesda, Maryland + 1 more",
      "locations": [
        {
          "city": "Fort Myers",
          "state": "Florida"
        },
        {
          "city": "Scarborough",
          "state": "Maine"
        },
        {
          "city": "Bethesda",
          "state": "Maryland"
        },
        {
          "city": "East Setauket",
          "state": "New York"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT02625935"
    },
    {
      "nct_id": "NCT01101438",
      "title": "A Phase III Randomized Trial of Metformin vs Placebo in Early Stage Breast Cancer",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE3"
      ],
      "conditions": [
        "Breast Cancer"
      ],
      "interventions": [
        {
          "name": "metformin hydrochloride",
          "type": "DRUG"
        },
        {
          "name": "placebo",
          "type": "OTHER"
        }
      ],
      "intervention_types": [
        "DRUG",
        "OTHER"
      ],
      "sponsor": "Canadian Cancer Trials Group",
      "sponsor_class": "NETWORK",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": "74 Years",
        "sex": "ALL",
        "summary": "18 Years to 74 Years"
      },
      "enrollment_count": 3649,
      "start_date": "2010-08-13",
      "completion_date": "2023-08-18",
      "has_results": true,
      "last_update_posted_date": "2023-09-13",
      "last_synced_at": "2026-07-22T00:08:01.997Z",
      "location_count": 280,
      "location_summary": "Anchorage, Alaska • Fairbanks, Alaska • Scottsdale, Arizona + 213 more",
      "locations": [
        {
          "city": "Anchorage",
          "state": "Alaska"
        },
        {
          "city": "Fairbanks",
          "state": "Alaska"
        },
        {
          "city": "Scottsdale",
          "state": "Arizona"
        },
        {
          "city": "Scottsdale",
          "state": "Arizona"
        },
        {
          "city": "Tucson",
          "state": "Arizona"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT01101438"
    },
    {
      "nct_id": "NCT07541079",
      "title": "A Study Evaluating Adherence, Tolerability, and Patient Reported Outcomes of Giredestrant in Participants With ER+/HER2- Early Breast Cancer Who Are Intolerant to Adjuvant Aromatase Inhibitor Therapy (novERA Breast Cancer)",
      "overall_status": "RECRUITING",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE3"
      ],
      "conditions": [
        "Early Breast Cancer"
      ],
      "interventions": [
        {
          "name": "Giredestrant",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "Genentech, Inc.",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": null,
        "sex": "FEMALE",
        "summary": "18 Years and older · Female only"
      },
      "enrollment_count": 300,
      "start_date": "2026-08-15",
      "completion_date": "2034-06-30",
      "has_results": false,
      "last_update_posted_date": "2026-07-20",
      "last_synced_at": "2026-07-22T00:08:01.997Z",
      "location_count": 1,
      "location_summary": "Fountain Valley, California",
      "locations": [
        {
          "city": "Fountain Valley",
          "state": "California"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT07541079"
    },
    {
      "nct_id": "NCT01515800",
      "title": "S1105: Text-Messaging Intervention to Reduce Early Discontinuation of AI Therapy in Women With Early-Stage Breast Cancer",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "NA"
      ],
      "conditions": [
        "Breast Cancer"
      ],
      "interventions": [
        {
          "name": "Text message reminder",
          "type": "BEHAVIORAL"
        }
      ],
      "intervention_types": [
        "BEHAVIORAL"
      ],
      "sponsor": "SWOG Cancer Research Network",
      "sponsor_class": "NETWORK",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": "120 Years",
        "sex": "FEMALE",
        "summary": "18 Years to 120 Years · Female only"
      },
      "enrollment_count": 724,
      "start_date": "2012-05",
      "completion_date": "2018-02",
      "has_results": false,
      "last_update_posted_date": "2018-03-08",
      "last_synced_at": "2026-07-22T00:08:01.997Z",
      "location_count": 204,
      "location_summary": "Anchorage, Alaska • Fort Smith, Arkansas • Little Rock, Arkansas + 144 more",
      "locations": [
        {
          "city": "Anchorage",
          "state": "Alaska"
        },
        {
          "city": "Fort Smith",
          "state": "Arkansas"
        },
        {
          "city": "Little Rock",
          "state": "Arkansas"
        },
        {
          "city": "Antioch",
          "state": "California"
        },
        {
          "city": "Fremont",
          "state": "California"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT01515800"
    },
    {
      "nct_id": "NCT01535066",
      "title": "S1200: Acupuncture, Sham Acupuncture, or Wait List for Joint Symptoms Related to Aromatase Inhibitors in Pts W/Early-Stage Breast Cancer",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "NA"
      ],
      "conditions": [
        "Breast Cancer",
        "Pain"
      ],
      "interventions": [
        {
          "name": "acupuncture therapy",
          "type": "PROCEDURE"
        },
        {
          "name": "sham acupuncture",
          "type": "PROCEDURE"
        }
      ],
      "intervention_types": [
        "PROCEDURE"
      ],
      "sponsor": "SWOG Cancer Research Network",
      "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": 226,
      "start_date": "2012-05-16",
      "completion_date": "2018-07-01",
      "has_results": false,
      "last_update_posted_date": "2022-12-07",
      "last_synced_at": "2026-07-22T00:08:01.997Z",
      "location_count": 47,
      "location_summary": "Antioch, California • Fremont, California • Los Angeles, California + 36 more",
      "locations": [
        {
          "city": "Antioch",
          "state": "California"
        },
        {
          "city": "Fremont",
          "state": "California"
        },
        {
          "city": "Los Angeles",
          "state": "California"
        },
        {
          "city": "Oakland",
          "state": "California"
        },
        {
          "city": "Redwood City",
          "state": "California"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT01535066"
    },
    {
      "nct_id": "NCT03137693",
      "title": "Preoperative Stereotactic Ablative Body Radiotherapy (SABR) for Early-Stage Breast Cancer",
      "overall_status": "TERMINATED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "NA"
      ],
      "conditions": [
        "Breast Cancer",
        "Breast Cancer Female",
        "Breast Adenocarcinoma"
      ],
      "interventions": [
        {
          "name": "Standard of Care Schedule Variation: SABR",
          "type": "OTHER"
        },
        {
          "name": "Breast-conserving Surgery",
          "type": "PROCEDURE"
        }
      ],
      "intervention_types": [
        "OTHER",
        "PROCEDURE"
      ],
      "sponsor": "H. Lee Moffitt Cancer Center and Research Institute",
      "sponsor_class": "OTHER",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "50 Years",
        "maximum_age": null,
        "sex": "FEMALE",
        "summary": "50 Years and older · Female only"
      },
      "enrollment_count": 20,
      "start_date": "2017-11-29",
      "completion_date": "2020-01-27",
      "has_results": true,
      "last_update_posted_date": "2023-02-23",
      "last_synced_at": "2026-07-22T00:08:01.997Z",
      "location_count": 1,
      "location_summary": "Tampa, Florida",
      "locations": [
        {
          "city": "Tampa",
          "state": "Florida"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT03137693"
    },
    {
      "nct_id": "NCT05914792",
      "title": "Longitudinal ctDNA Surveillance for Older Women With ER+ Breast Cancer Who Omit Surgery",
      "overall_status": "ACTIVE_NOT_RECRUITING",
      "study_type": "OBSERVATIONAL",
      "phases": [],
      "conditions": [
        "Breast Cancer"
      ],
      "interventions": [],
      "intervention_types": [],
      "sponsor": "University of Pittsburgh",
      "sponsor_class": "OTHER",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "70 Years",
        "maximum_age": null,
        "sex": "FEMALE",
        "summary": "70 Years and older · Female only"
      },
      "enrollment_count": 49,
      "start_date": "2022-04-19",
      "completion_date": "2026-07-01",
      "has_results": false,
      "last_update_posted_date": "2025-04-10",
      "last_synced_at": "2026-07-22T00:08:01.997Z",
      "location_count": 1,
      "location_summary": "Pittsburgh, Pennsylvania",
      "locations": [
        {
          "city": "Pittsburgh",
          "state": "Pennsylvania"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT05914792"
    }
  ]
}