{
  "api_version": "1",
  "request": {
    "url": "https://clinicaltrialsfind.com/api/v1/search.json?intervention=letrozole+2.5+mg&page=4",
    "query": {
      "intervention": "letrozole 2.5 mg",
      "page": 4
    },
    "page_size": 10
  },
  "pagination": {
    "page": 4,
    "page_size": 10,
    "total_count": 133,
    "total_pages": 14,
    "next_page_url": "https://clinicaltrialsfind.com/api/v1/search.json?intervention=letrozole+2.5+mg&page=5&page_size=10",
    "previous_page_url": "https://clinicaltrialsfind.com/api/v1/search.json?intervention=letrozole+2.5+mg&page=3&page_size=10"
  },
  "source": "remote",
  "last_synced_at": "2026-10-12T11:08:04.738Z",
  "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": "NCT06218303",
      "title": "Prototype DAA/TAA Vaccine Targeting MUC1 for Immune Interception and Prevention in Ductal Carcinoma In Situ",
      "overall_status": "RECRUITING",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE1"
      ],
      "conditions": [
        "Ductal Carcinoma in Situ"
      ],
      "interventions": [
        {
          "name": "MUC1 Peptide Vaccine",
          "type": "BIOLOGICAL"
        },
        {
          "name": "Hiltonol®",
          "type": "DRUG"
        },
        {
          "name": "Aromatase Inhibitor",
          "type": "DRUG"
        },
        {
          "name": "Selective estrogen receptor modulator (SERM)",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "BIOLOGICAL",
        "DRUG"
      ],
      "sponsor": "Finn, Olivera, PhD",
      "sponsor_class": "OTHER",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": null,
        "sex": "FEMALE",
        "summary": "18 Years and older · Female only"
      },
      "enrollment_count": 50,
      "start_date": "2024-02-07",
      "completion_date": "2029-12-31",
      "has_results": false,
      "last_update_posted_date": "2026-08-18",
      "last_synced_at": "2026-10-12T11:08:04.738Z",
      "location_count": 1,
      "location_summary": "Pittsburgh, Pennsylvania",
      "locations": [
        {
          "city": "Pittsburgh",
          "state": "Pennsylvania"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT06218303"
    },
    {
      "nct_id": "NCT03007979",
      "title": "Alternative Dosing Schedule of Palbociclib in Metastatic Hormone Receptor Positive Breast Cancer",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE2"
      ],
      "conditions": [
        "Breast Cancer",
        "Breast Carcinoma",
        "Cancer of Breast",
        "Malignant Tumor of Breast"
      ],
      "interventions": [
        {
          "name": "Palbociclib",
          "type": "DRUG"
        },
        {
          "name": "Letrozole",
          "type": "DRUG"
        },
        {
          "name": "Fulvestrant",
          "type": "DRUG"
        },
        {
          "name": "Optional research biopsy",
          "type": "PROCEDURE"
        },
        {
          "name": "Goserelin",
          "type": "DRUG"
        },
        {
          "name": "Research blood draw",
          "type": "PROCEDURE"
        },
        {
          "name": "Circulating tumor cell blood draw",
          "type": "PROCEDURE"
        },
        {
          "name": "Tumor biopsy (optional)",
          "type": "PROCEDURE"
        }
      ],
      "intervention_types": [
        "DRUG",
        "PROCEDURE"
      ],
      "sponsor": "Washington University School of Medicine",
      "sponsor_class": "OTHER",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": null,
        "sex": "FEMALE",
        "summary": "18 Years and older · Female only"
      },
      "enrollment_count": 55,
      "start_date": "2017-06-15",
      "completion_date": "2023-03-31",
      "has_results": true,
      "last_update_posted_date": "2024-03-20",
      "last_synced_at": "2026-10-12T11:08:04.738Z",
      "location_count": 2,
      "location_summary": "St Louis, Missouri • Lincoln, Nebraska",
      "locations": [
        {
          "city": "St Louis",
          "state": "Missouri"
        },
        {
          "city": "Lincoln",
          "state": "Nebraska"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT03007979"
    },
    {
      "nct_id": "NCT05649956",
      "title": "Letrozole in Uterine Leiomyosarcoma",
      "overall_status": "RECRUITING",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE2"
      ],
      "conditions": [
        "Uterine Leiomyosarcoma"
      ],
      "interventions": [
        {
          "name": "Letrozole",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "GOG Foundation",
      "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": 40,
      "start_date": "2024-07-17",
      "completion_date": "2029-07-30",
      "has_results": false,
      "last_update_posted_date": "2026-07-30",
      "last_synced_at": "2026-10-12T11:08:04.738Z",
      "location_count": 34,
      "location_summary": "Aurora, Colorado • Highlands Ranch, Colorado • Fort Lauderdale, Florida + 27 more",
      "locations": [
        {
          "city": "Aurora",
          "state": "Colorado"
        },
        {
          "city": "Highlands Ranch",
          "state": "Colorado"
        },
        {
          "city": "Fort Lauderdale",
          "state": "Florida"
        },
        {
          "city": "Miami Beach",
          "state": "Florida"
        },
        {
          "city": "Atlanta",
          "state": "Georgia"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT05649956"
    },
    {
      "nct_id": "NCT07085767",
      "title": "Palazestrant in Combination With Ribociclib for the First-line Treatment of ER+/HER2- Advanced Breast Cancer",
      "overall_status": "RECRUITING",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE3"
      ],
      "conditions": [
        "Breast Cancer",
        "Locally Advanced Breast Cancer",
        "Metastatic Breast Cancer",
        "ER Positive Breast Cancer",
        "HER2 Negative Breast Carcinoma"
      ],
      "interventions": [
        {
          "name": "Palazestrant",
          "type": "DRUG"
        },
        {
          "name": "Letrozole-matching placebo",
          "type": "DRUG"
        },
        {
          "name": "Ribociclib",
          "type": "DRUG"
        },
        {
          "name": "Letrozole",
          "type": "DRUG"
        },
        {
          "name": "Palazestrant matching-placebo",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "Olema Pharmaceuticals, Inc.",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "18 Years and older"
      },
      "enrollment_count": 1000,
      "start_date": "2025-11-03",
      "completion_date": "2032-01",
      "has_results": false,
      "last_update_posted_date": "2026-09-23",
      "last_synced_at": "2026-10-12T11:08:04.738Z",
      "location_count": 62,
      "location_summary": "Hot Springs, Arkansas • Beverly Hills, California • La Jolla, California + 54 more",
      "locations": [
        {
          "city": "Hot Springs",
          "state": "Arkansas"
        },
        {
          "city": "Beverly Hills",
          "state": "California"
        },
        {
          "city": "La Jolla",
          "state": "California"
        },
        {
          "city": "Los Alamitos",
          "state": "California"
        },
        {
          "city": "Oakland",
          "state": "California"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT07085767"
    },
    {
      "nct_id": "NCT03078751",
      "title": "Adjuvant Ribociclib With Endocrine Therapy in Hormone Receptor+/HER2- High Risk Early Breast Cancer",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE2"
      ],
      "conditions": [
        "Breast Cancer"
      ],
      "interventions": [
        {
          "name": "Ribociclib",
          "type": "DRUG"
        },
        {
          "name": "Adjuvant endocrine therapy",
          "type": "DRUG"
        },
        {
          "name": "Placebo",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "Novartis Pharmaceuticals",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "18 Years and older"
      },
      "enrollment_count": 54,
      "start_date": "2017-06-20",
      "completion_date": "2020-03-09",
      "has_results": true,
      "last_update_posted_date": "2021-10-11",
      "last_synced_at": "2026-10-12T11:08:04.738Z",
      "location_count": 33,
      "location_summary": "Tucson, Arizona • Fayetteville, Arkansas • Bakersfield, California + 28 more",
      "locations": [
        {
          "city": "Tucson",
          "state": "Arizona"
        },
        {
          "city": "Fayetteville",
          "state": "Arkansas"
        },
        {
          "city": "Bakersfield",
          "state": "California"
        },
        {
          "city": "Los Angeles",
          "state": "California"
        },
        {
          "city": "Oxnard",
          "state": "California"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT03078751"
    },
    {
      "nct_id": "NCT00696072",
      "title": "Randomized Phase II Trial of Letrozole With or Without Dasatinib as First and Second-line Treatment for Hormone Receptor-positive, HER2-negative Post-menopausal Breast Cancer That is Unresectable, Locally Recurrent or Metastatic",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE2"
      ],
      "conditions": [
        "Metastatic Breast Cancer"
      ],
      "interventions": [
        {
          "name": "Dasatinib",
          "type": "DRUG"
        },
        {
          "name": "Letrozole",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "Bristol-Myers Squibb",
      "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": 120,
      "start_date": "2008-08",
      "completion_date": "2014-06",
      "has_results": true,
      "last_update_posted_date": "2016-06-13",
      "last_synced_at": "2026-10-12T11:08:04.738Z",
      "location_count": 27,
      "location_summary": "Sedona, Arizona • Tucson, Arizona • Denver, Colorado + 22 more",
      "locations": [
        {
          "city": "Sedona",
          "state": "Arizona"
        },
        {
          "city": "Tucson",
          "state": "Arizona"
        },
        {
          "city": "Denver",
          "state": "Colorado"
        },
        {
          "city": "Hudson",
          "state": "Florida"
        },
        {
          "city": "Carmel",
          "state": "Indiana"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT00696072"
    },
    {
      "nct_id": "NCT00291109",
      "title": "An Examination of Predictors of Indicators of Response to Letrozole 2.5 mg",
      "overall_status": "COMPLETED",
      "study_type": "OBSERVATIONAL",
      "phases": [],
      "conditions": [
        "Breast Cancer"
      ],
      "interventions": [
        {
          "name": "letrozole 2.5 mg",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "University of Kansas",
      "sponsor_class": "OTHER",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": null,
        "sex": "FEMALE",
        "summary": "18 Years and older · Female only"
      },
      "enrollment_count": 40,
      "start_date": "2003-01",
      "completion_date": "2005-07",
      "has_results": false,
      "last_update_posted_date": "2008-09-16",
      "last_synced_at": "2026-10-12T11:08:04.738Z",
      "location_count": 1,
      "location_summary": "Kansas City, Kansas",
      "locations": [
        {
          "city": "Kansas City",
          "state": "Kansas"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT00291109"
    },
    {
      "nct_id": "NCT02907918",
      "title": "Neoadjuvant Study of Palbociclib in Combination With Letrozole and Trastuzumab in Stage II-III ER+ HER2+ Breast Cancer",
      "overall_status": "TERMINATED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE2"
      ],
      "conditions": [
        "Breast Cancer",
        "Cancer of Breast",
        "Breast Carcinoma"
      ],
      "interventions": [
        {
          "name": "Palbociclib",
          "type": "DRUG"
        },
        {
          "name": "Letrozole",
          "type": "DRUG"
        },
        {
          "name": "Trastuzumab",
          "type": "BIOLOGICAL"
        },
        {
          "name": "Goserelin",
          "type": "DRUG"
        },
        {
          "name": "Breast surgery",
          "type": "PROCEDURE"
        },
        {
          "name": "Research tumor biopsy",
          "type": "PROCEDURE"
        },
        {
          "name": "Research bone marrow (OPTIONAL)",
          "type": "PROCEDURE"
        },
        {
          "name": "Research blood sample",
          "type": "PROCEDURE"
        },
        {
          "name": "Research blood for germline DNA",
          "type": "GENETIC"
        },
        {
          "name": "Blood for detection of circulating tumor cells",
          "type": "PROCEDURE"
        }
      ],
      "intervention_types": [
        "DRUG",
        "BIOLOGICAL",
        "PROCEDURE",
        "GENETIC"
      ],
      "sponsor": "Washington University School of Medicine",
      "sponsor_class": "OTHER",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "18 Years and older"
      },
      "enrollment_count": 26,
      "start_date": "2017-06-30",
      "completion_date": "2020-09-23",
      "has_results": true,
      "last_update_posted_date": "2021-09-29",
      "last_synced_at": "2026-10-12T11:08:04.738Z",
      "location_count": 3,
      "location_summary": "Phoenix, Arizona • St Louis, Missouri • Buffalo, New York",
      "locations": [
        {
          "city": "Phoenix",
          "state": "Arizona"
        },
        {
          "city": "St Louis",
          "state": "Missouri"
        },
        {
          "city": "Buffalo",
          "state": "New York"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT02907918"
    },
    {
      "nct_id": "NCT04852887",
      "title": "De-Escalation of Breast Radiation Trial for Hormone Sensitive, HER-2 Negative, Oncotype Recurrence Score Less Than or Equal to 18 Breast Cancer (DEBRA)",
      "overall_status": "RECRUITING",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE3"
      ],
      "conditions": [
        "Stage I Breast Cancer"
      ],
      "interventions": [
        {
          "name": "Radiation and Endocrine Therapy (Tamoxifen, Anastrozol, Letrozole, Exemestane)",
          "type": "OTHER"
        },
        {
          "name": "Endocrine Therapy (Tamoxifen, Anastrozol, Letrozole, Exemestane)",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "OTHER",
        "DRUG"
      ],
      "sponsor": "NRG Oncology",
      "sponsor_class": "OTHER",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "50 Years",
        "maximum_age": "70 Years",
        "sex": "ALL",
        "summary": "50 Years to 70 Years"
      },
      "enrollment_count": 1670,
      "start_date": "2021-06-23",
      "completion_date": "2041-07",
      "has_results": false,
      "last_update_posted_date": "2026-04-23",
      "last_synced_at": "2026-10-12T11:08:04.738Z",
      "location_count": 812,
      "location_summary": "Birmingham, Alabama • Mobile, Alabama • Kingman, Arizona + 553 more",
      "locations": [
        {
          "city": "Birmingham",
          "state": "Alabama"
        },
        {
          "city": "Mobile",
          "state": "Alabama"
        },
        {
          "city": "Kingman",
          "state": "Arizona"
        },
        {
          "city": "Phoenix",
          "state": "Arizona"
        },
        {
          "city": "Phoenix",
          "state": "Arizona"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT04852887"
    },
    {
      "nct_id": "NCT03962647",
      "title": "A 2-Week Ketogenic Diet in Combination With Letrozole to Modulate PI3K Signaling in ER+ Breast Cancer",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "EARLY_PHASE1"
      ],
      "conditions": [
        "Estrogen Receptor-positive Breast Cancer"
      ],
      "interventions": [
        {
          "name": "2-Week Ketogenic Diet",
          "type": "DIETARY_SUPPLEMENT"
        },
        {
          "name": "Letrozole",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DIETARY_SUPPLEMENT",
        "DRUG"
      ],
      "sponsor": "Vanderbilt-Ingram Cancer Center",
      "sponsor_class": "OTHER",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": null,
        "sex": "FEMALE",
        "summary": "18 Years and older · Female only"
      },
      "enrollment_count": 31,
      "start_date": "2019-07-08",
      "completion_date": "2024-07-14",
      "has_results": false,
      "last_update_posted_date": "2026-04-30",
      "last_synced_at": "2026-10-12T11:08:04.738Z",
      "location_count": 1,
      "location_summary": "Nashville, Tennessee",
      "locations": [
        {
          "city": "Nashville",
          "state": "Tennessee"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT03962647"
    }
  ]
}