{
  "api_version": "1",
  "request": {
    "url": "https://clinicaltrialsfind.com/api/v1/search.json?intervention=letrozole+%28Femara%29&page=4",
    "query": {
      "intervention": "letrozole (Femara)",
      "page": 4
    },
    "page_size": 10
  },
  "pagination": {
    "page": 4,
    "page_size": 10,
    "total_count": 336,
    "total_pages": 34,
    "next_page_url": "https://clinicaltrialsfind.com/api/v1/search.json?intervention=letrozole+%28Femara%29&page=5&page_size=10",
    "previous_page_url": "https://clinicaltrialsfind.com/api/v1/search.json?intervention=letrozole+%28Femara%29&page=3&page_size=10"
  },
  "source": "remote",
  "last_synced_at": "2026-10-11T03:05:08.357Z",
  "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": "NCT06760637",
      "title": "Study of PF-07220060 With Letrozole in Adults With HR-positive HER2-negative Breast Cancer Who Have Not Received Anticancer Treatment for Advanced/Metastatic Disease",
      "overall_status": "ACTIVE_NOT_RECRUITING",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE3"
      ],
      "conditions": [
        "Breast Cancer"
      ],
      "interventions": [
        {
          "name": "PF-07220060",
          "type": "DRUG"
        },
        {
          "name": "letrozole",
          "type": "DRUG"
        },
        {
          "name": "abemaciclib",
          "type": "DRUG"
        },
        {
          "name": "palbociclib",
          "type": "DRUG"
        },
        {
          "name": "ribociclib",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "Pfizer",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "18 Years and older"
      },
      "enrollment_count": 1035,
      "start_date": "2025-01-06",
      "completion_date": "2037-12-29",
      "has_results": false,
      "last_update_posted_date": "2026-05-19",
      "last_synced_at": "2026-10-11T03:05:08.357Z",
      "location_count": 218,
      "location_summary": "Birmingham, Alabama • Chandler, Arizona • Gilbert, Arizona + 135 more",
      "locations": [
        {
          "city": "Birmingham",
          "state": "Alabama"
        },
        {
          "city": "Birmingham",
          "state": "Alabama"
        },
        {
          "city": "Birmingham",
          "state": "Alabama"
        },
        {
          "city": "Chandler",
          "state": "Arizona"
        },
        {
          "city": "Gilbert",
          "state": "Arizona"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT06760637"
    },
    {
      "nct_id": "NCT01814397",
      "title": "Pilot Study to Evaluate the Effect of Aromatase Inhibitor Therapy on Pain Threshold in Breast Cancer Patients",
      "overall_status": "COMPLETED",
      "study_type": "OBSERVATIONAL",
      "phases": [],
      "conditions": [
        "Breast Cancer",
        "Pain",
        "Arthralgia"
      ],
      "interventions": [
        {
          "name": "Anastrozole",
          "type": "DRUG"
        },
        {
          "name": "exemestane",
          "type": "DRUG"
        },
        {
          "name": "letrozole",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "University of Michigan Rogel Cancer Center",
      "sponsor_class": "OTHER",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "21 Years",
        "maximum_age": null,
        "sex": "FEMALE",
        "summary": "21 Years and older · Female only"
      },
      "enrollment_count": 50,
      "start_date": "2009-07",
      "completion_date": "2013-02",
      "has_results": true,
      "last_update_posted_date": "2024-02-07",
      "last_synced_at": "2026-10-11T03:05:08.357Z",
      "location_count": 1,
      "location_summary": "Ann Arbor, Michigan",
      "locations": [
        {
          "city": "Ann Arbor",
          "state": "Michigan"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT01814397"
    },
    {
      "nct_id": "NCT03050398",
      "title": "A Companion Sample Collection Protocol to Support the Discovery of Breast Cancer Aberrations With Treatment of CDK4/6 Therapy/LEE011/Ribociclib",
      "overall_status": "TERMINATED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE3"
      ],
      "conditions": [
        "Breast Cancer"
      ],
      "interventions": [
        {
          "name": "Ribociclib",
          "type": "DRUG"
        },
        {
          "name": "letrozole",
          "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": 8,
      "start_date": "2017-06-07",
      "completion_date": "2019-03-08",
      "has_results": true,
      "last_update_posted_date": "2020-05-28",
      "last_synced_at": "2026-10-11T03:05:08.357Z",
      "location_count": 6,
      "location_summary": "Sedona, Arizona • Long Beach, California • Charlotte, North Carolina + 3 more",
      "locations": [
        {
          "city": "Sedona",
          "state": "Arizona"
        },
        {
          "city": "Long Beach",
          "state": "California"
        },
        {
          "city": "Charlotte",
          "state": "North Carolina"
        },
        {
          "city": "Florence",
          "state": "South Carolina"
        },
        {
          "city": "Rock Hill",
          "state": "South Carolina"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT03050398"
    },
    {
      "nct_id": "NCT06757634",
      "title": "Phase 3 Study of Gedatolisib as First-Line Treatment for Patients With HR-Positive, HER2-Negative Advanced Breast Cancer (VIKTORIA-2)",
      "overall_status": "RECRUITING",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE3"
      ],
      "conditions": [
        "Breast Cancer"
      ],
      "interventions": [
        {
          "name": "Arm A: Gedatolisib + Palbociclib + Fulvestrant",
          "type": "DRUG"
        },
        {
          "name": "Arm B: Ribociclib + Fulvestrant",
          "type": "DRUG"
        },
        {
          "name": "Arm C: Gedatolisib + Palbociclib + Letrozole",
          "type": "DRUG"
        },
        {
          "name": "Arm D: Ribociclib + Letrozole",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "Celcuity Inc",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "18 Years and older"
      },
      "enrollment_count": 1180,
      "start_date": "2025-07-24",
      "completion_date": "2033-07-30",
      "has_results": false,
      "last_update_posted_date": "2026-10-09",
      "last_synced_at": "2026-10-11T03:05:08.357Z",
      "location_count": 30,
      "location_summary": "Jonesboro, Arkansas • Little Rock, Arkansas • Duarte, California + 27 more",
      "locations": [
        {
          "city": "Jonesboro",
          "state": "Arkansas"
        },
        {
          "city": "Little Rock",
          "state": "Arkansas"
        },
        {
          "city": "Duarte",
          "state": "California"
        },
        {
          "city": "Fullerton",
          "state": "California"
        },
        {
          "city": "Los Angeles",
          "state": "California"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT06757634"
    },
    {
      "nct_id": "NCT01439711",
      "title": "Letrozole in Treating Postmenopausal Women With Ductal Carcinoma in Situ",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE2"
      ],
      "conditions": [
        "Breast Cancer"
      ],
      "interventions": [
        {
          "name": "letrozole",
          "type": "DRUG"
        },
        {
          "name": "MRI",
          "type": "PROCEDURE"
        },
        {
          "name": "conventional surgery",
          "type": "PROCEDURE"
        }
      ],
      "intervention_types": [
        "DRUG",
        "PROCEDURE"
      ],
      "sponsor": "Alliance for Clinical Trials in Oncology",
      "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": 108,
      "start_date": "2012-02",
      "completion_date": "2018-01",
      "has_results": true,
      "last_update_posted_date": "2018-03-27",
      "last_synced_at": "2026-10-11T03:05:08.357Z",
      "location_count": 32,
      "location_summary": "Los Angeles, California • Oakland, California • San Francisco, California + 22 more",
      "locations": [
        {
          "city": "Los Angeles",
          "state": "California"
        },
        {
          "city": "Oakland",
          "state": "California"
        },
        {
          "city": "San Francisco",
          "state": "California"
        },
        {
          "city": "Denver",
          "state": "Colorado"
        },
        {
          "city": "Newark",
          "state": "Delaware"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT01439711"
    },
    {
      "nct_id": "NCT04316169",
      "title": "Hydroxychloroquine, Abemaciclib and Endocrine Therapy in Hormone Receptor Positive (HR+)/Her 2 Negative Breast Cancer",
      "overall_status": "WITHDRAWN",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE1"
      ],
      "conditions": [
        "Solid Tumor",
        "Advanced Breast Cancer"
      ],
      "interventions": [
        {
          "name": "Abemaciclib",
          "type": "DRUG"
        },
        {
          "name": "Hydroxychloroquine 200 mg",
          "type": "DRUG"
        },
        {
          "name": "Faslodex",
          "type": "DRUG"
        },
        {
          "name": "Anastrazole",
          "type": "DRUG"
        },
        {
          "name": "Letrozole",
          "type": "DRUG"
        },
        {
          "name": "Hydroxychloroquine 400 mg",
          "type": "DRUG"
        },
        {
          "name": "Hydroxychloroquine 600 mg",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "Medical College of Wisconsin",
      "sponsor_class": "OTHER",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "18 Years and older"
      },
      "enrollment_count": 0,
      "start_date": "2021-10-21",
      "completion_date": "2028-01",
      "has_results": false,
      "last_update_posted_date": "2022-12-23",
      "last_synced_at": "2026-10-11T03:05:08.357Z",
      "location_count": 1,
      "location_summary": "Milwaukee, Wisconsin",
      "locations": [
        {
          "city": "Milwaukee",
          "state": "Wisconsin"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT04316169"
    },
    {
      "nct_id": "NCT05826964",
      "title": "Levels of Circulating Tumor DNA as a Predictive Marker for Early Switch in Treatment for Patients With Metastatic (Stage IV) Breast Cancer",
      "overall_status": "ACTIVE_NOT_RECRUITING",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE2"
      ],
      "conditions": [
        "Breast Cancer",
        "ER-positive Breast Cancer",
        "HER2-negative Breast Cancer",
        "Metastatic Breast Cancer"
      ],
      "interventions": [
        {
          "name": "AI+CDK4/6i",
          "type": "DRUG"
        },
        {
          "name": "SERD+CDK4/6i",
          "type": "DRUG"
        },
        {
          "name": "mTOR inhibitor + AI",
          "type": "DRUG"
        },
        {
          "name": "mTOR inhibitor + SERD",
          "type": "DRUG"
        },
        {
          "name": "mTOR inhibitor + Selective estrogen receptor modulator",
          "type": "DRUG"
        },
        {
          "name": "PI3K inhibitor + SERD",
          "type": "DRUG"
        },
        {
          "name": "PI3K inhibitor + AI",
          "type": "DRUG"
        },
        {
          "name": "Chemotherapy",
          "type": "DRUG"
        },
        {
          "name": "Oral SERD",
          "type": "DRUG"
        },
        {
          "name": "PARPi",
          "type": "DRUG"
        },
        {
          "name": "AKT inhibitor",
          "type": "DRUG"
        },
        {
          "name": "Step 3 Arm 2",
          "type": "OTHER"
        }
      ],
      "intervention_types": [
        "DRUG",
        "OTHER"
      ],
      "sponsor": "University of Miami",
      "sponsor_class": "OTHER",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "18 Years and older"
      },
      "enrollment_count": 24,
      "start_date": "2023-06-12",
      "completion_date": "2029-07-31",
      "has_results": false,
      "last_update_posted_date": "2026-01-13",
      "last_synced_at": "2026-10-11T03:05:08.357Z",
      "location_count": 1,
      "location_summary": "Miami, Florida",
      "locations": [
        {
          "city": "Miami",
          "state": "Florida"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT05826964"
    },
    {
      "nct_id": "NCT00790816",
      "title": "Continuation Study of Lapatinib Monotherapy or Lapatinib in Combination With Other Anti-cancer Agents",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE1"
      ],
      "conditions": [
        "Neoplasms, Breast"
      ],
      "interventions": [
        {
          "name": "Lapatinib in combination with an anti-cancer agent",
          "type": "DRUG"
        },
        {
          "name": "Lapatinib",
          "type": "DRUG"
        },
        {
          "name": "Lapatinib in combination with an anti-cancer agent as specified by parent protocol",
          "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": 500,
      "start_date": "2008-10",
      "completion_date": "2016-08-19",
      "has_results": false,
      "last_update_posted_date": "2018-02-28",
      "last_synced_at": "2026-10-11T03:05:08.357Z",
      "location_count": 15,
      "location_summary": "Scottsdale, Arizona • Tucson, Arizona • Santa Monica, California + 12 more",
      "locations": [
        {
          "city": "Scottsdale",
          "state": "Arizona"
        },
        {
          "city": "Tucson",
          "state": "Arizona"
        },
        {
          "city": "Santa Monica",
          "state": "California"
        },
        {
          "city": "Washington D.C.",
          "state": "District of Columbia"
        },
        {
          "city": "Fort Myers",
          "state": "Florida"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT00790816"
    },
    {
      "nct_id": "NCT07391774",
      "title": "Testing Whether Hormone Therapy With Ribociclib is as Effective as Chemotherapy Followed by Hormone Therapy With Ribociclib for the Treatment of High Anatomic Stage Breast Cancer With Low Recurrence Risk, The RxFINE-Low Trial",
      "overall_status": "RECRUITING",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE3"
      ],
      "conditions": [
        "Anatomic Stage II Breast Cancer AJCC v8",
        "Anatomic Stage IIIA Breast Cancer AJCC v8",
        "Anatomic Stage IIIC Breast Cancer AJCC v8",
        "Estrogen Receptor-Positive Breast Carcinoma",
        "HER2-Negative Breast Carcinoma"
      ],
      "interventions": [
        {
          "name": "Anastrozole",
          "type": "DRUG"
        },
        {
          "name": "Biospecimen Collection",
          "type": "PROCEDURE"
        },
        {
          "name": "Bone Scan",
          "type": "PROCEDURE"
        },
        {
          "name": "Chemotherapy",
          "type": "DRUG"
        },
        {
          "name": "Computed Tomography",
          "type": "PROCEDURE"
        },
        {
          "name": "Exemestane",
          "type": "DRUG"
        },
        {
          "name": "Letrozole",
          "type": "DRUG"
        },
        {
          "name": "Oncotype DX Breast Cancer Assay",
          "type": "PROCEDURE"
        },
        {
          "name": "Positron Emission Tomography",
          "type": "PROCEDURE"
        },
        {
          "name": "Ribociclib Succinate",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG",
        "PROCEDURE"
      ],
      "sponsor": "National Cancer Institute (NCI)",
      "sponsor_class": "NIH",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "18 Years and older"
      },
      "enrollment_count": 1978,
      "start_date": "2026-08-10",
      "completion_date": "2029-07-31",
      "has_results": false,
      "last_update_posted_date": "2026-10-07",
      "last_synced_at": "2026-10-11T03:05:08.357Z",
      "location_count": 201,
      "location_summary": "Jonesboro, Arkansas • Auburn, California • Berkeley, California + 167 more",
      "locations": [
        {
          "city": "Jonesboro",
          "state": "Arkansas"
        },
        {
          "city": "Auburn",
          "state": "California"
        },
        {
          "city": "Berkeley",
          "state": "California"
        },
        {
          "city": "Beverly Hills",
          "state": "California"
        },
        {
          "city": "Irvine",
          "state": "California"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT07391774"
    },
    {
      "nct_id": "NCT00194779",
      "title": "Combination Chemotherapy and Filgrastim Before Surgery in Treating Patients With HER2-Positive Breast Cancer That Can Be Removed By Surgery",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE2"
      ],
      "conditions": [
        "Estrogen Receptor-negative Breast Cancer",
        "Estrogen Receptor-positive Breast Cancer",
        "HER2-positive Breast Cancer",
        "Progesterone Receptor-negative Breast Cancer",
        "Progesterone Receptor-positive Breast Cancer",
        "Stage IA Breast Cancer",
        "Stage IB Breast Cancer",
        "Stage II Breast Cancer",
        "Stage IIIA Breast Cancer"
      ],
      "interventions": [
        {
          "name": "doxorubicin hydrochloride",
          "type": "DRUG"
        },
        {
          "name": "cyclophosphamide",
          "type": "DRUG"
        },
        {
          "name": "paclitaxel",
          "type": "DRUG"
        },
        {
          "name": "filgrastim",
          "type": "BIOLOGICAL"
        },
        {
          "name": "capecitabine",
          "type": "DRUG"
        },
        {
          "name": "methotrexate",
          "type": "DRUG"
        },
        {
          "name": "vinorelbine tartrate",
          "type": "DRUG"
        },
        {
          "name": "needle biopsy",
          "type": "PROCEDURE"
        },
        {
          "name": "therapeutic conventional surgery",
          "type": "PROCEDURE"
        },
        {
          "name": "immunohistochemistry staining method",
          "type": "OTHER"
        },
        {
          "name": "trastuzumab",
          "type": "BIOLOGICAL"
        },
        {
          "name": "tamoxifen citrate",
          "type": "DRUG"
        },
        {
          "name": "letrozole",
          "type": "DRUG"
        },
        {
          "name": "laboratory biomarker analysis",
          "type": "OTHER"
        }
      ],
      "intervention_types": [
        "DRUG",
        "BIOLOGICAL",
        "PROCEDURE",
        "OTHER"
      ],
      "sponsor": "University of Washington",
      "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": "2003-10",
      "completion_date": "2011-06",
      "has_results": true,
      "last_update_posted_date": "2018-03-12",
      "last_synced_at": "2026-10-11T03:05:08.357Z",
      "location_count": 1,
      "location_summary": "Seattle, Washington",
      "locations": [
        {
          "city": "Seattle",
          "state": "Washington"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT00194779"
    }
  ]
}