{
  "api_version": "1",
  "request": {
    "url": "https://clinicaltrialsfind.com/api/v1/search.json?intervention=Istradefylline",
    "query": {
      "intervention": "Istradefylline"
    },
    "page_size": 10
  },
  "pagination": {
    "page": 1,
    "page_size": 10,
    "total_count": 21,
    "total_pages": 3,
    "next_page_url": "https://clinicaltrialsfind.com/api/v1/search.json?intervention=Istradefylline&page=2&page_size=10",
    "previous_page_url": null
  },
  "source": "remote",
  "last_synced_at": "2026-09-05T09:27:11.067Z",
  "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": "NCT00203957",
      "title": "Study of KW-6002 (Istradefylline) in Parkinson's Disease in Patients With Motor Response Complications on Levodopa",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE3"
      ],
      "conditions": [
        "Parkinson's Disease"
      ],
      "interventions": [
        {
          "name": "Istradefylline",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "University of Chicago",
      "sponsor_class": "OTHER",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "18 Years and older"
      },
      "enrollment_count": 10,
      "start_date": "2005-03",
      "completion_date": "2007-02",
      "has_results": false,
      "last_update_posted_date": "2013-06-11",
      "last_synced_at": "2026-09-05T09:27:11.067Z",
      "location_count": 1,
      "location_summary": "Chicago, Illinois",
      "locations": [
        {
          "city": "Chicago",
          "state": "Illinois"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT00203957"
    },
    {
      "nct_id": "NCT02610231",
      "title": "Long Term Study of Istradefylline in Subjects With Moderate to Severe Parkinson's Disease",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE3"
      ],
      "conditions": [
        "Idiopathic Parkinson's Disease"
      ],
      "interventions": [
        {
          "name": "Istradefylline 20 mg or 40 mg",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "Kyowa Kirin Co., Ltd.",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "30 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "30 Years and older"
      },
      "enrollment_count": 239,
      "start_date": "2015-12",
      "completion_date": "2017-12-20",
      "has_results": true,
      "last_update_posted_date": "2024-04-25",
      "last_synced_at": "2026-09-05T09:27:11.067Z",
      "location_count": 23,
      "location_summary": "Phoenix, Arizona • Sun City, Arizona • Tucson, Arizona + 20 more",
      "locations": [
        {
          "city": "Phoenix",
          "state": "Arizona"
        },
        {
          "city": "Sun City",
          "state": "Arizona"
        },
        {
          "city": "Tucson",
          "state": "Arizona"
        },
        {
          "city": "Fountain Valley",
          "state": "California"
        },
        {
          "city": "Los Angeles",
          "state": "California"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT02610231"
    },
    {
      "nct_id": "NCT01968031",
      "title": "A 12-week Randomized Study to Evaluate Oral Istradefylline in Subjects With Moderate to Severe Parkinson's Disease",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE3"
      ],
      "conditions": [
        "Idiopathic Parkinson's Disease"
      ],
      "interventions": [
        {
          "name": "Istradefylline 40 mg",
          "type": "DRUG"
        },
        {
          "name": "Istradefylline 20 mg",
          "type": "DRUG"
        },
        {
          "name": "Placebo",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "Kyowa Kirin Co., Ltd.",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "30 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "30 Years and older"
      },
      "enrollment_count": 613,
      "start_date": "2013-10",
      "completion_date": "2016-10",
      "has_results": true,
      "last_update_posted_date": "2024-04-25",
      "last_synced_at": "2026-09-05T09:27:11.067Z",
      "location_count": 41,
      "location_summary": "Phoenix, Arizona • Sun City, Arizona • Tucson, Arizona + 36 more",
      "locations": [
        {
          "city": "Phoenix",
          "state": "Arizona"
        },
        {
          "city": "Sun City",
          "state": "Arizona"
        },
        {
          "city": "Tucson",
          "state": "Arizona"
        },
        {
          "city": "Fountain Valley",
          "state": "California"
        },
        {
          "city": "Irvine",
          "state": "California"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT01968031"
    },
    {
      "nct_id": "NCT00456794",
      "title": "12-Week, Double-Blind, Placebo-Controlled Study of 20 and 60 mg/Day Istradefylline in Parkinson's Disease Patients on Levodopa/Carbodopa",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE2"
      ],
      "conditions": [
        "Parkinson's Disease"
      ],
      "interventions": [
        {
          "name": "Istradefylline (KW-6002)",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "Kyowa Kirin, Inc.",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "30 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "30 Years and older"
      },
      "enrollment_count": 325,
      "start_date": "2002-03",
      "completion_date": "2003-10",
      "has_results": false,
      "last_update_posted_date": "2024-04-25",
      "last_synced_at": "2026-09-05T09:27:11.067Z",
      "location_count": 1,
      "location_summary": "Princeton, New Jersey",
      "locations": [
        {
          "city": "Princeton",
          "state": "New Jersey"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT00456794"
    },
    {
      "nct_id": "NCT00006337",
      "title": "KW-6002 to Treat Parkinson's Disease",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE2"
      ],
      "conditions": [
        "Parkinson's Disease"
      ],
      "interventions": [
        {
          "name": "KW-6002",
          "type": "DRUG"
        },
        {
          "name": "IV Levodopa",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "National Institute of Neurological Disorders and Stroke (NINDS)",
      "sponsor_class": "NIH",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": null,
        "maximum_age": null,
        "sex": "ALL",
        "summary": "Not listed"
      },
      "enrollment_count": 16,
      "start_date": "2000-10",
      "completion_date": "2002-01",
      "has_results": false,
      "last_update_posted_date": "2008-03-04",
      "last_synced_at": "2026-09-05T09:27:11.067Z",
      "location_count": 1,
      "location_summary": "Bethesda, Maryland",
      "locations": [
        {
          "city": "Bethesda",
          "state": "Maryland"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT00006337"
    },
    {
      "nct_id": "NCT02174250",
      "title": "The Effect of Rifampin on the Metabolism of Istradefylline in Healthy Volunteers.",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE1"
      ],
      "conditions": [
        "Parkinson's Disease"
      ],
      "interventions": [
        {
          "name": "Istradefylline 40 mg",
          "type": "DRUG"
        },
        {
          "name": "Rifampin 300mg BID + istradefylline 40mg Day 8 only",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "Kyowa Kirin Co., Ltd.",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": "65 Years",
        "sex": "ALL",
        "summary": "18 Years to 65 Years"
      },
      "enrollment_count": 20,
      "start_date": "2014-06",
      "completion_date": "2014-12",
      "has_results": false,
      "last_update_posted_date": "2024-04-25",
      "last_synced_at": "2026-09-05T09:27:11.067Z",
      "location_count": 1,
      "location_summary": "Tempe, Arizona",
      "locations": [
        {
          "city": "Tempe",
          "state": "Arizona"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT02174250"
    },
    {
      "nct_id": "NCT05333549",
      "title": "Istradefylline for Parkinson Disease With Cognitive Impairment",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE2"
      ],
      "conditions": [
        "Parkinson Disease",
        "Cognitive Impairment"
      ],
      "interventions": [
        {
          "name": "Istradefylline medication",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "Virginia Commonwealth University",
      "sponsor_class": "OTHER",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "50 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "50 Years and older"
      },
      "enrollment_count": 15,
      "start_date": "2022-07-18",
      "completion_date": "2025-06-09",
      "has_results": false,
      "last_update_posted_date": "2025-07-28",
      "last_synced_at": "2026-09-05T09:27:11.067Z",
      "location_count": 1,
      "location_summary": "Richmond, Virginia",
      "locations": [
        {
          "city": "Richmond",
          "state": "Virginia"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT05333549"
    },
    {
      "nct_id": "NCT00955045",
      "title": "A Long-Term, Safety Study With a Flexible Dose Range of KW-6002 in Patients With Motor Response Complications on Levodopa/Carbidopa Therapy",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE2",
        "PHASE3"
      ],
      "conditions": [
        "Parkinson's Disease"
      ],
      "interventions": [
        {
          "name": "istradefylline",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "Kyowa Kirin, Inc.",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "30 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "30 Years and older"
      },
      "enrollment_count": null,
      "start_date": "2002-08",
      "completion_date": "2003-10",
      "has_results": false,
      "last_update_posted_date": "2024-04-25",
      "last_synced_at": "2026-09-05T09:27:11.067Z",
      "location_count": 1,
      "location_summary": "Princeton, New Jersey",
      "locations": [
        {
          "city": "Princeton",
          "state": "New Jersey"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT00955045"
    },
    {
      "nct_id": "NCT02609477",
      "title": "A Study to Evaluate Abuse Potential of Istradefylline",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE1"
      ],
      "conditions": [
        "Drug Abuse"
      ],
      "interventions": [
        {
          "name": "Istradefylline",
          "type": "DRUG"
        },
        {
          "name": "Phentermine 45 mg",
          "type": "DRUG"
        },
        {
          "name": "Placebo",
          "type": "OTHER"
        }
      ],
      "intervention_types": [
        "DRUG",
        "OTHER"
      ],
      "sponsor": "Kyowa Kirin Co., Ltd.",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": "55 Years",
        "sex": "ALL",
        "summary": "18 Years to 55 Years"
      },
      "enrollment_count": 42,
      "start_date": "2016-01",
      "completion_date": "2016-07",
      "has_results": false,
      "last_update_posted_date": "2024-04-25",
      "last_synced_at": "2026-09-05T09:27:11.067Z",
      "location_count": 1,
      "location_summary": "Salt Lake City, Utah",
      "locations": [
        {
          "city": "Salt Lake City",
          "state": "Utah"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT02609477"
    },
    {
      "nct_id": "NCT00199381",
      "title": "An Extension of Istradefylline in North American Parkinson's Disease Patients Who Have Completed Study 6002-INT-001",
      "overall_status": "TERMINATED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE3"
      ],
      "conditions": [
        "Parkinson's Disease"
      ],
      "interventions": [
        {
          "name": "Istradefylline",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "Kyowa Kirin, Inc.",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "30 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "30 Years and older"
      },
      "enrollment_count": 504,
      "start_date": "2005-10",
      "completion_date": "2008-10",
      "has_results": true,
      "last_update_posted_date": "2024-05-17",
      "last_synced_at": "2026-09-05T09:27:11.067Z",
      "location_count": 1,
      "location_summary": "Princeton, New Jersey",
      "locations": [
        {
          "city": "Princeton",
          "state": "New Jersey"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT00199381"
    }
  ]
}