{
  "api_version": "1",
  "request": {
    "url": "https://clinicaltrialsfind.com/api/v1/search.json?intervention=Endocrine+Therapy+and+a+CDK+4%2F6+inhibitor",
    "query": {
      "intervention": "Endocrine Therapy and a CDK 4/6 inhibitor"
    },
    "page_size": 10
  },
  "pagination": {
    "page": 1,
    "page_size": 10,
    "total_count": 20,
    "total_pages": 2,
    "next_page_url": "https://clinicaltrialsfind.com/api/v1/search.json?intervention=Endocrine+Therapy+and+a+CDK+4%2F6+inhibitor&page=2&page_size=10",
    "previous_page_url": null
  },
  "source": "remote",
  "last_synced_at": "2026-10-10T06:48:54.875Z",
  "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": "NCT03439735",
      "title": "Determinants of Resistance to Endocrine Therapy and a Cyclin-dependent Kinases 4 and 6 (CDK4/6) Inhibitor for HR+ MBC",
      "overall_status": "ACTIVE_NOT_RECRUITING",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE2"
      ],
      "conditions": [
        "Breast Cancer"
      ],
      "interventions": [
        {
          "name": "Endocrine Therapy and a CDK 4/6 inhibitor",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins",
      "sponsor_class": "OTHER",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": "100 Years",
        "sex": "ALL",
        "summary": "18 Years to 100 Years"
      },
      "enrollment_count": 45,
      "start_date": "2018-07-20",
      "completion_date": "2027-11-01",
      "has_results": false,
      "last_update_posted_date": "2026-08-07",
      "last_synced_at": "2026-10-10T06:48:54.875Z",
      "location_count": 1,
      "location_summary": "Baltimore, Maryland",
      "locations": [
        {
          "city": "Baltimore",
          "state": "Maryland"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT03439735"
    },
    {
      "nct_id": "NCT06380751",
      "title": "Saruparib (AZD5305) Plus Camizestrant or Plus Endocrine Therapy, Compared With CDK4/6 Inhibitor Plus Endocrine Therapy or Plus Camizestrant in HR-Positive, HER2-Negative (IHC 0, 1+, 2+/ ISH Non-amplified), BRCA1, BRCA2, or PALB2m Advanced Breast Cancer",
      "overall_status": "RECRUITING",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE3"
      ],
      "conditions": [
        "Advanced Breast Cancer"
      ],
      "interventions": [
        {
          "name": "Saruparib (AZD5305)",
          "type": "DRUG"
        },
        {
          "name": "Camizestrant",
          "type": "DRUG"
        },
        {
          "name": "Abemaciclib",
          "type": "DRUG"
        },
        {
          "name": "Ribociclib",
          "type": "DRUG"
        },
        {
          "name": "Palbociclib",
          "type": "DRUG"
        },
        {
          "name": "Fulvestrant",
          "type": "DRUG"
        },
        {
          "name": "Letrozole",
          "type": "DRUG"
        },
        {
          "name": "Anastrozole",
          "type": "DRUG"
        },
        {
          "name": "Exemestane",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "AstraZeneca",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "18 Years and older"
      },
      "enrollment_count": 788,
      "start_date": "2024-08-01",
      "completion_date": "2031-12-30",
      "has_results": false,
      "last_update_posted_date": "2026-09-02",
      "last_synced_at": "2026-10-10T06:48:54.875Z",
      "location_count": 57,
      "location_summary": "Gilbert, Arizona • Fountain Valley, California • Glendale, California + 49 more",
      "locations": [
        {
          "city": "Gilbert",
          "state": "Arizona"
        },
        {
          "city": "Fountain Valley",
          "state": "California"
        },
        {
          "city": "Glendale",
          "state": "California"
        },
        {
          "city": "Los Angeles",
          "state": "California"
        },
        {
          "city": "Newport Beach",
          "state": "California"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT06380751"
    },
    {
      "nct_id": "NCT07112053",
      "title": "A Vaccine (STEMVAC) With Standard Endocrine-Based Therapy or Chemotherapy for the Treatment of Metastatic Hormone Receptor Positive, HER2 Negative Breast Cancer",
      "overall_status": "RECRUITING",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE2"
      ],
      "conditions": [
        "Anatomic Stage IV Breast Cancer AJCC v8",
        "Metastatic HER2-Negative Breast Carcinoma",
        "Metastatic Hormone Receptor-Positive Breast Carcinoma"
      ],
      "interventions": [
        {
          "name": "CD105/Yb-1/SOX2/CDH3/MDM2-polyepitope Plasmid DNA Vaccine",
          "type": "BIOLOGICAL"
        },
        {
          "name": "Capecitabine",
          "type": "DRUG"
        },
        {
          "name": "Computed Tomography",
          "type": "PROCEDURE"
        },
        {
          "name": "Cyclin-Dependent Kinase 4 Inhibitor",
          "type": "DRUG"
        },
        {
          "name": "Cyclin-Dependent Kinase 6 Inhibitor",
          "type": "DRUG"
        },
        {
          "name": "F-18 16 Alpha-Fluoroestradiol",
          "type": "DRUG"
        },
        {
          "name": "Hormone Therapy",
          "type": "DRUG"
        },
        {
          "name": "Positron Emission Tomography",
          "type": "PROCEDURE"
        },
        {
          "name": "Biopsy Procedure",
          "type": "PROCEDURE"
        },
        {
          "name": "Biospecimen Collection",
          "type": "PROCEDURE"
        },
        {
          "name": "Abemaciclib",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "BIOLOGICAL",
        "DRUG",
        "PROCEDURE"
      ],
      "sponsor": "University of Washington",
      "sponsor_class": "OTHER",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "18 Years and older"
      },
      "enrollment_count": 40,
      "start_date": "2025-11-17",
      "completion_date": "2028-12-31",
      "has_results": false,
      "last_update_posted_date": "2026-04-06",
      "last_synced_at": "2026-10-10T06:48:54.875Z",
      "location_count": 1,
      "location_summary": "Seattle, Washington",
      "locations": [
        {
          "city": "Seattle",
          "state": "Washington"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT07112053"
    },
    {
      "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": "2026-10-10T06:48:54.875Z",
      "location_count": 1,
      "location_summary": "Miami, Florida",
      "locations": [
        {
          "city": "Miami",
          "state": "Florida"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT05826964"
    },
    {
      "nct_id": "NCT03134638",
      "title": "A Study of SY-1365 in Adult Patients With Advanced Solid Tumors",
      "overall_status": "TERMINATED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE1"
      ],
      "conditions": [
        "Advanced Solid Tumors",
        "Ovarian Cancer",
        "Breast Cancer"
      ],
      "interventions": [
        {
          "name": "SY-1365 (Part 1)",
          "type": "DRUG"
        },
        {
          "name": "Carboplatin",
          "type": "DRUG"
        },
        {
          "name": "Fulvestrant",
          "type": "DRUG"
        },
        {
          "name": "SY-1365 (Cohort 2)",
          "type": "DRUG"
        },
        {
          "name": "SY-1365 (Cohort 5)",
          "type": "DRUG"
        },
        {
          "name": "SY-1365 (Part 2 Single Agent)",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "Syros Pharmaceuticals",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "18 Years and older"
      },
      "enrollment_count": 107,
      "start_date": "2017-05-12",
      "completion_date": "2020-06-24",
      "has_results": false,
      "last_update_posted_date": "2021-03-09",
      "last_synced_at": "2026-10-10T06:48:54.875Z",
      "location_count": 15,
      "location_summary": "Birmingham, Alabama • Scottsdale, Arizona • San Francisco, California + 11 more",
      "locations": [
        {
          "city": "Birmingham",
          "state": "Alabama"
        },
        {
          "city": "Scottsdale",
          "state": "Arizona"
        },
        {
          "city": "San Francisco",
          "state": "California"
        },
        {
          "city": "Chicago",
          "state": "Illinois"
        },
        {
          "city": "Boston",
          "state": "Massachusetts"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT03134638"
    },
    {
      "nct_id": "NCT06016738",
      "title": "OP-1250 (Palazestrant) vs. Standard of Care for the Treatment of ER+/HER2- Advanced Breast Cancer",
      "overall_status": "ACTIVE_NOT_RECRUITING",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE3"
      ],
      "conditions": [
        "Breast Cancer",
        "Advanced Breast Cancer",
        "Metastatic Breast Cancer",
        "ER Positive Breast Cancer",
        "HER2 Negative Breast Carcinoma"
      ],
      "interventions": [
        {
          "name": "Palazestrant",
          "type": "DRUG"
        },
        {
          "name": "Fulvestrant",
          "type": "DRUG"
        },
        {
          "name": "Anastrozole",
          "type": "DRUG"
        },
        {
          "name": "Letrozole",
          "type": "DRUG"
        },
        {
          "name": "Exemestane",
          "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": 510,
      "start_date": "2023-11-16",
      "completion_date": "2028-02-29",
      "has_results": false,
      "last_update_posted_date": "2026-08-13",
      "last_synced_at": "2026-10-10T06:48:54.875Z",
      "location_count": 47,
      "location_summary": "Tucson, Arizona • Fountain Valley, California • Glendale, California + 39 more",
      "locations": [
        {
          "city": "Tucson",
          "state": "Arizona"
        },
        {
          "city": "Fountain Valley",
          "state": "California"
        },
        {
          "city": "Glendale",
          "state": "California"
        },
        {
          "city": "La Jolla",
          "state": "California"
        },
        {
          "city": "Los Alamitos",
          "state": "California"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT06016738"
    },
    {
      "nct_id": "NCT04247126",
      "title": "A Study of SY 5609, a Selective CDK7 Inhibitor, in Advanced Solid Tumors",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE1"
      ],
      "conditions": [
        "Advanced Solid Tumor",
        "Breast Cancer",
        "Small-cell Lung Cancer",
        "Pancreatic Cancer"
      ],
      "interventions": [
        {
          "name": "SY-5609",
          "type": "DRUG"
        },
        {
          "name": "Fulvestrant",
          "type": "DRUG"
        },
        {
          "name": "Gemcitabine",
          "type": "DRUG"
        },
        {
          "name": "Nab-paclitaxel",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "Syros Pharmaceuticals",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "18 Years and older"
      },
      "enrollment_count": 105,
      "start_date": "2020-01-23",
      "completion_date": "2023-03-30",
      "has_results": false,
      "last_update_posted_date": "2023-10-27",
      "last_synced_at": "2026-10-10T06:48:54.875Z",
      "location_count": 16,
      "location_summary": "Gilbert, Arizona • Los Angeles, California • Orlando, Florida + 11 more",
      "locations": [
        {
          "city": "Gilbert",
          "state": "Arizona"
        },
        {
          "city": "Los Angeles",
          "state": "California"
        },
        {
          "city": "Los Angeles",
          "state": "California"
        },
        {
          "city": "Orlando",
          "state": "Florida"
        },
        {
          "city": "Atlanta",
          "state": "Georgia"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT04247126"
    },
    {
      "nct_id": "NCT01723774",
      "title": "PD 0332991 and Anastrozole for Stage 2 or 3 Estrogen Receptor Positive and HER2 Negative Breast Cancer",
      "overall_status": "ACTIVE_NOT_RECRUITING",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE2"
      ],
      "conditions": [
        "Breast Neoplasms"
      ],
      "interventions": [
        {
          "name": "PD0332991",
          "type": "DRUG"
        },
        {
          "name": "Anastrozole",
          "type": "DRUG"
        },
        {
          "name": "Goserelin",
          "type": "DRUG"
        },
        {
          "name": "Surgery (standard of care)",
          "type": "PROCEDURE"
        },
        {
          "name": "Tumor biopsy",
          "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": 84,
      "start_date": "2013-04-10",
      "completion_date": "2027-11-07",
      "has_results": true,
      "last_update_posted_date": "2026-09-25",
      "last_synced_at": "2026-10-10T06:48:54.875Z",
      "location_count": 4,
      "location_summary": "Birmingham, Alabama • Scottsdale, Arizona • Rochester, Minnesota + 1 more",
      "locations": [
        {
          "city": "Birmingham",
          "state": "Alabama"
        },
        {
          "city": "Scottsdale",
          "state": "Arizona"
        },
        {
          "city": "Rochester",
          "state": "Minnesota"
        },
        {
          "city": "St Louis",
          "state": "Missouri"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT01723774"
    },
    {
      "nct_id": "NCT06408168",
      "title": "Phase II Study of REPotrectinib With or Without Fulvestrant in Patients With Hormone Receptor-positive Human Epidermal Growth Factor 2-negative Metastatic Invasive LObular Carcinoma Who Received a Prior Endocrine Therapy in Combination With Cyclin-dependent Kinase 4 and 6 Inhibitor (REPLOT Trial)",
      "overall_status": "TERMINATED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE2"
      ],
      "conditions": [
        "Hormone Receptor-positive Human Epidermal Growth Factor 2-negative",
        "Metastatic Invasive LObular Carcinoma"
      ],
      "interventions": [
        {
          "name": "Fulvestrant",
          "type": "DRUG"
        },
        {
          "name": "Repotrectinib",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "M.D. Anderson Cancer Center",
      "sponsor_class": "OTHER",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "18 Years and older"
      },
      "enrollment_count": 6,
      "start_date": "2024-08-08",
      "completion_date": "2025-12-08",
      "has_results": false,
      "last_update_posted_date": "2026-01-05",
      "last_synced_at": "2026-10-10T06:48:54.875Z",
      "location_count": 1,
      "location_summary": "Houston, Texas",
      "locations": [
        {
          "city": "Houston",
          "state": "Texas"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT06408168"
    },
    {
      "nct_id": "NCT03056755",
      "title": "Study Assessing the Efficacy and Safety of Alpelisib Plus Fulvestrant or Letrozole, Based on Prior Endocrine Therapy, in Patients With PIK3CA Mutant, HR+, HER2- Advanced Breast Cancer Who Have Progressed on or After Prior Treatments",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE2"
      ],
      "conditions": [
        "Breast Cancer"
      ],
      "interventions": [
        {
          "name": "Alpelisib",
          "type": "DRUG"
        },
        {
          "name": "Fulvestrant",
          "type": "DRUG"
        },
        {
          "name": "Letrozole",
          "type": "DRUG"
        },
        {
          "name": "Goserelin",
          "type": "DRUG"
        },
        {
          "name": "Leuprolide",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "Novartis Pharmaceuticals",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": "99 Years",
        "sex": "ALL",
        "summary": "18 Years to 99 Years"
      },
      "enrollment_count": 383,
      "start_date": "2017-08-29",
      "completion_date": "2024-11-12",
      "has_results": true,
      "last_update_posted_date": "2026-01-13",
      "last_synced_at": "2026-10-10T06:48:54.875Z",
      "location_count": 25,
      "location_summary": "Gilbert, Arizona • Phoenix, Arizona • Anaheim, California + 20 more",
      "locations": [
        {
          "city": "Gilbert",
          "state": "Arizona"
        },
        {
          "city": "Phoenix",
          "state": "Arizona"
        },
        {
          "city": "Anaheim",
          "state": "California"
        },
        {
          "city": "Beverly Hills",
          "state": "California"
        },
        {
          "city": "Irvine",
          "state": "California"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT03056755"
    }
  ]
}