{
  "api_version": "1",
  "request": {
    "url": "https://clinicaltrialsfind.com/api/v1/search.json?intervention=Niraparib-Placebo",
    "query": {
      "intervention": "Niraparib-Placebo"
    },
    "page_size": 10
  },
  "pagination": {
    "page": 1,
    "page_size": 10,
    "total_count": 8,
    "total_pages": 1,
    "next_page_url": null,
    "previous_page_url": null
  },
  "source": "remote",
  "last_synced_at": "2026-09-18T08:33:52.298Z",
  "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": "NCT03981796",
      "title": "A Study to Evaluate Dostarlimab Plus Carboplatin-paclitaxel Versus Placebo Plus Carboplatin-paclitaxel in Participants With Recurrent or Primary Advanced Endometrial Cancer",
      "overall_status": "ACTIVE_NOT_RECRUITING",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE3"
      ],
      "conditions": [
        "Neoplasms"
      ],
      "interventions": [
        {
          "name": "Dostarlimab",
          "type": "BIOLOGICAL"
        },
        {
          "name": "Placebo matching dostarlimab",
          "type": "DRUG"
        },
        {
          "name": "Carboplatin",
          "type": "DRUG"
        },
        {
          "name": "Paclitaxel",
          "type": "DRUG"
        },
        {
          "name": "Niraparib",
          "type": "DRUG"
        },
        {
          "name": "Placebo matching Niraparib",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "BIOLOGICAL",
        "DRUG"
      ],
      "sponsor": "Tesaro, 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": 785,
      "start_date": "2019-07-18",
      "completion_date": "2026-11-26",
      "has_results": false,
      "last_update_posted_date": "2025-09-03",
      "last_synced_at": "2026-09-18T08:33:52.298Z",
      "location_count": 59,
      "location_summary": "Phoenix, Arizona • Scottsdale, Arizona • Tucson, Arizona + 49 more",
      "locations": [
        {
          "city": "Phoenix",
          "state": "Arizona"
        },
        {
          "city": "Scottsdale",
          "state": "Arizona"
        },
        {
          "city": "Tucson",
          "state": "Arizona"
        },
        {
          "city": "Tucson",
          "state": "Arizona"
        },
        {
          "city": "Newport Beach",
          "state": "California"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT03981796"
    },
    {
      "nct_id": "NCT02655016",
      "title": "A Study of Niraparib (GSK3985771) Maintenance Treatment in Participants With Advanced Ovarian Cancer Following Response on Front-Line Platinum-Based Chemotherapy",
      "overall_status": "ACTIVE_NOT_RECRUITING",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE3"
      ],
      "conditions": [
        "Ovarian Neoplasms"
      ],
      "interventions": [
        {
          "name": "Niraparib",
          "type": "DRUG"
        },
        {
          "name": "Placebo",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "Tesaro, 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": 733,
      "start_date": "2016-07-11",
      "completion_date": "2026-05-29",
      "has_results": true,
      "last_update_posted_date": "2026-03-10",
      "last_synced_at": "2026-09-18T08:33:52.298Z",
      "location_count": 47,
      "location_summary": "Tempe, Arizona • Tucson, Arizona • San Francisco, California + 41 more",
      "locations": [
        {
          "city": "Tempe",
          "state": "Arizona"
        },
        {
          "city": "Tucson",
          "state": "Arizona"
        },
        {
          "city": "Tucson",
          "state": "Arizona"
        },
        {
          "city": "San Francisco",
          "state": "California"
        },
        {
          "city": "San Francisco",
          "state": "California"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT02655016"
    },
    {
      "nct_id": "NCT03602859",
      "title": "A Comparison of Platinum-based Therapy With TSR-042 and Niraparib Versus Standard of Care (SOC) Platinum-based Therapy as First-line Treatment of Stage III or IV Nonmucinous Epithelial Ovarian Cancer",
      "overall_status": "ACTIVE_NOT_RECRUITING",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE3"
      ],
      "conditions": [
        "Ovarian Neoplasms",
        "Ovarian, Fallopian Tube and Primary Peritoneal Carcinoma"
      ],
      "interventions": [
        {
          "name": "Niraparib",
          "type": "DRUG"
        },
        {
          "name": "Dostarlimab (TSR-042)",
          "type": "DRUG"
        },
        {
          "name": "Standard of care",
          "type": "DRUG"
        },
        {
          "name": "Dostarlimab-Placebo",
          "type": "DRUG"
        },
        {
          "name": "Niraparib-Placebo",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "Tesaro, 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": 1400,
      "start_date": "2018-10-11",
      "completion_date": "2029-04-30",
      "has_results": true,
      "last_update_posted_date": "2025-12-31",
      "last_synced_at": "2026-09-18T08:33:52.298Z",
      "location_count": 65,
      "location_summary": "Anchorage, Alaska • Phoenix, Arizona • Tucson, Arizona + 55 more",
      "locations": [
        {
          "city": "Anchorage",
          "state": "Alaska"
        },
        {
          "city": "Phoenix",
          "state": "Arizona"
        },
        {
          "city": "Tucson",
          "state": "Arizona"
        },
        {
          "city": "Los Angeles",
          "state": "California"
        },
        {
          "city": "Los Angeles",
          "state": "California"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT03602859"
    },
    {
      "nct_id": "NCT03748641",
      "title": "A Study of Niraparib in Combination With Abiraterone Acetate and Prednisone Versus Abiraterone Acetate and Prednisone for Treatment of Participants With Metastatic Prostate Cancer",
      "overall_status": "ACTIVE_NOT_RECRUITING",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE3"
      ],
      "conditions": [
        "Castration-Resistant Prostatic Cancer"
      ],
      "interventions": [
        {
          "name": "Niraparib",
          "type": "DRUG"
        },
        {
          "name": "Abiraterone Acetate",
          "type": "DRUG"
        },
        {
          "name": "Prednisone",
          "type": "DRUG"
        },
        {
          "name": "Placebo",
          "type": "DRUG"
        },
        {
          "name": "New Formulation of Niraparib and Abiraterone Acetate (AA)",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "Janssen Research & Development, LLC",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": null,
        "sex": "MALE",
        "summary": "18 Years and older · Male only"
      },
      "enrollment_count": 765,
      "start_date": "2019-01-25",
      "completion_date": "2027-02-27",
      "has_results": true,
      "last_update_posted_date": "2026-07-31",
      "last_synced_at": "2026-09-18T08:33:52.298Z",
      "location_count": 47,
      "location_summary": "Homewood, Alabama • Phoenix, Arizona • Tucson, Arizona + 40 more",
      "locations": [
        {
          "city": "Homewood",
          "state": "Alabama"
        },
        {
          "city": "Phoenix",
          "state": "Arizona"
        },
        {
          "city": "Tucson",
          "state": "Arizona"
        },
        {
          "city": "Little Rock",
          "state": "Arkansas"
        },
        {
          "city": "Riverside",
          "state": "California"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT03748641"
    },
    {
      "nct_id": "NCT04915755",
      "title": "Efficacy and Safety Comparison of Niraparib to Placebo in Participants With Human Epidermal Growth Factor 2 Negative (HER2-) Breast Cancer Susceptibility Gene Mutation (BRCAmut) or Triple-Negative Breast Cancer (TNBC) With Molecular Disease",
      "overall_status": "ACTIVE_NOT_RECRUITING",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE3"
      ],
      "conditions": [
        "Neoplasms, Breast"
      ],
      "interventions": [
        {
          "name": "Niraparib",
          "type": "DRUG"
        },
        {
          "name": "Placebo",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "GlaxoSmithKline",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "18 Years and older"
      },
      "enrollment_count": 40,
      "start_date": "2021-06-28",
      "completion_date": "2025-12-31",
      "has_results": true,
      "last_update_posted_date": "2025-07-16",
      "last_synced_at": "2026-09-18T08:33:52.298Z",
      "location_count": 24,
      "location_summary": "Burbank, California • Duarte, California • Palo Alto, California + 20 more",
      "locations": [
        {
          "city": "Burbank",
          "state": "California"
        },
        {
          "city": "Duarte",
          "state": "California"
        },
        {
          "city": "Palo Alto",
          "state": "California"
        },
        {
          "city": "San Francisco",
          "state": "California"
        },
        {
          "city": "Aurora",
          "state": "Colorado"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT04915755"
    },
    {
      "nct_id": "NCT04497844",
      "title": "A Study of Niraparib in Combination With Abiraterone Acetate and Prednisone Versus Abiraterone Acetate and Prednisone for the Treatment of Participants With Deleterious Germline or Somatic Homologous Recombination Repair (HRR) Gene-MutatedProstatic Neoplasms (mCSPC)",
      "overall_status": "ACTIVE_NOT_RECRUITING",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE3"
      ],
      "conditions": [
        "Prostatic Neoplasms"
      ],
      "interventions": [
        {
          "name": "Niraparib+ Abiraterone acetate fixed dose combination (FDC)",
          "type": "COMBINATION_PRODUCT"
        },
        {
          "name": "Abiraterone acetate (AA)",
          "type": "DRUG"
        },
        {
          "name": "Prednisone",
          "type": "DRUG"
        },
        {
          "name": "Placebo FDC",
          "type": "DRUG"
        },
        {
          "name": "Placebo AA",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "COMBINATION_PRODUCT",
        "DRUG"
      ],
      "sponsor": "Janssen Research & Development, LLC",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": null,
        "sex": "MALE",
        "summary": "18 Years and older · Male only"
      },
      "enrollment_count": 696,
      "start_date": "2020-09-23",
      "completion_date": "2027-11-01",
      "has_results": true,
      "last_update_posted_date": "2026-09-14",
      "last_synced_at": "2026-09-18T08:33:52.298Z",
      "location_count": 53,
      "location_summary": "Homewood, Alabama • Phoenix, Arizona • Tucson, Arizona + 45 more",
      "locations": [
        {
          "city": "Homewood",
          "state": "Alabama"
        },
        {
          "city": "Phoenix",
          "state": "Arizona"
        },
        {
          "city": "Tucson",
          "state": "Arizona"
        },
        {
          "city": "Los Angeles",
          "state": "California"
        },
        {
          "city": "Orange",
          "state": "California"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT04497844"
    },
    {
      "nct_id": "NCT01847274",
      "title": "A Maintenance Study With Niraparib Versus Placebo in Patients With Platinum Sensitive Ovarian Cancer",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE3"
      ],
      "conditions": [
        "Ovarian Neoplasms",
        "Platinum Sensitive Ovarian Cancer"
      ],
      "interventions": [
        {
          "name": "Active comparator: Niraparib",
          "type": "DRUG"
        },
        {
          "name": "placebo",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "Tesaro, 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": 596,
      "start_date": "2013-06-21",
      "completion_date": "2021-12-26",
      "has_results": true,
      "last_update_posted_date": "2023-06-02",
      "last_synced_at": "2026-09-18T08:33:52.298Z",
      "location_count": 35,
      "location_summary": "Phoenix, Arizona • Tucson, Arizona • Los Angeles, California + 27 more",
      "locations": [
        {
          "city": "Phoenix",
          "state": "Arizona"
        },
        {
          "city": "Tucson",
          "state": "Arizona"
        },
        {
          "city": "Los Angeles",
          "state": "California"
        },
        {
          "city": "Los Angeles",
          "state": "California"
        },
        {
          "city": "Palo Alto",
          "state": "California"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT01847274"
    },
    {
      "nct_id": "NCT04475939",
      "title": "Placebo-controlled Study Comparing Niraparib Plus Pembrolizumab Versus Placebo Plus Pembrolizumab as Maintenance Therapy in Participants With Advanced/Metastatic Non-Small Cell Lung Cancer",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE3"
      ],
      "conditions": [
        "Lung Cancer, Non-Small Cell"
      ],
      "interventions": [
        {
          "name": "Niraparib",
          "type": "DRUG"
        },
        {
          "name": "Pembrolizumab",
          "type": "BIOLOGICAL"
        },
        {
          "name": "Placebo",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG",
        "BIOLOGICAL"
      ],
      "sponsor": "GlaxoSmithKline",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "18 Years and older"
      },
      "enrollment_count": 666,
      "start_date": "2020-10-26",
      "completion_date": "2026-03-23",
      "has_results": true,
      "last_update_posted_date": "2026-06-18",
      "last_synced_at": "2026-09-18T08:33:52.298Z",
      "location_count": 21,
      "location_summary": "Fullerton, California • Los Angeles, California • Lone Tree, Colorado + 18 more",
      "locations": [
        {
          "city": "Fullerton",
          "state": "California"
        },
        {
          "city": "Los Angeles",
          "state": "California"
        },
        {
          "city": "Lone Tree",
          "state": "Colorado"
        },
        {
          "city": "Norwich",
          "state": "Connecticut"
        },
        {
          "city": "Tallahassee",
          "state": "Florida"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT04475939"
    }
  ]
}