{
  "api_version": "1",
  "request": {
    "url": "https://clinicaltrialsfind.com/api/v1/search.json?intervention=Tetrahydrobiopterin&page=2",
    "query": {
      "intervention": "Tetrahydrobiopterin",
      "page": 2
    },
    "page_size": 10
  },
  "pagination": {
    "page": 2,
    "page_size": 10,
    "total_count": 61,
    "total_pages": 7,
    "next_page_url": "https://clinicaltrialsfind.com/api/v1/search.json?intervention=Tetrahydrobiopterin&page=3&page_size=10",
    "previous_page_url": "https://clinicaltrialsfind.com/api/v1/search.json?intervention=Tetrahydrobiopterin&page=1&page_size=10"
  },
  "source": "remote",
  "last_synced_at": "2026-09-30T11:06:51.226Z",
  "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": "NCT00827762",
      "title": "Behavioral Effects of Kuvan in Children With Mild Phenylketonuria",
      "overall_status": "TERMINATED",
      "study_type": "OBSERVATIONAL",
      "phases": [],
      "conditions": [
        "Phenylketonuria"
      ],
      "interventions": [
        {
          "name": "Kuvan",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "Washington University School of Medicine",
      "sponsor_class": "OTHER",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "6 Years",
        "maximum_age": "18 Years",
        "sex": "ALL",
        "summary": "6 Years to 18 Years"
      },
      "enrollment_count": 2,
      "start_date": "2009-01",
      "completion_date": "2010-01",
      "has_results": false,
      "last_update_posted_date": "2013-12-05",
      "last_synced_at": "2026-09-30T11:06:51.226Z",
      "location_count": 4,
      "location_summary": "Chicago, Illinois • Columbia, Missouri • St Louis, Missouri + 1 more",
      "locations": [
        {
          "city": "Chicago",
          "state": "Illinois"
        },
        {
          "city": "Columbia",
          "state": "Missouri"
        },
        {
          "city": "St Louis",
          "state": "Missouri"
        },
        {
          "city": "Portland",
          "state": "Oregon"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT00827762"
    },
    {
      "nct_id": "NCT00688844",
      "title": "Nutritional and Neurotransmitter Changes in PKU Subjects on BH4",
      "overall_status": "COMPLETED",
      "study_type": "OBSERVATIONAL",
      "phases": [],
      "conditions": [
        "Phenylketonuria"
      ],
      "interventions": [
        {
          "name": "KuvanTM Therapy",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "Emory University",
      "sponsor_class": "OTHER",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "4 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "4 Years and older"
      },
      "enrollment_count": 58,
      "start_date": "2008-10",
      "completion_date": "2010-10",
      "has_results": true,
      "last_update_posted_date": "2015-06-08",
      "last_synced_at": "2026-09-30T11:06:51.226Z",
      "location_count": 2,
      "location_summary": "Atlanta, Georgia • Decatur, Georgia",
      "locations": [
        {
          "city": "Atlanta",
          "state": "Georgia"
        },
        {
          "city": "Decatur",
          "state": "Georgia"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT00688844"
    },
    {
      "nct_id": "NCT01274026",
      "title": "Evaluation of Behavior, Executive Function, Neurotransmitter Function and Genomic Expression Kuvan Nonresponders",
      "overall_status": "COMPLETED",
      "study_type": "OBSERVATIONAL",
      "phases": [],
      "conditions": [
        "Phenylketonuria",
        "Behavior and Behavior Mechanisms",
        "PAH Gene Expression"
      ],
      "interventions": [
        {
          "name": "sapropterin dihydrochloride",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "Tulane University School of Medicine",
      "sponsor_class": "OTHER",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "2 Years",
        "maximum_age": "21 Years",
        "sex": "ALL",
        "summary": "2 Years to 21 Years"
      },
      "enrollment_count": 21,
      "start_date": "2011-01",
      "completion_date": "2013-12",
      "has_results": false,
      "last_update_posted_date": "2023-08-14",
      "last_synced_at": "2026-09-30T11:06:51.226Z",
      "location_count": 1,
      "location_summary": "New Orleans, Louisiana",
      "locations": [
        {
          "city": "New Orleans",
          "state": "Louisiana"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT01274026"
    },
    {
      "nct_id": "NCT04368624",
      "title": "PKU Skin Stripping",
      "overall_status": "COMPLETED",
      "study_type": "OBSERVATIONAL",
      "phases": [],
      "conditions": [
        "Phenylketonurias"
      ],
      "interventions": [
        {
          "name": "Skin Tape",
          "type": "OTHER"
        },
        {
          "name": "Blood Draw",
          "type": "DIAGNOSTIC_TEST"
        }
      ],
      "intervention_types": [
        "OTHER",
        "DIAGNOSTIC_TEST"
      ],
      "sponsor": "Children's Hospital Medical Center, Cincinnati",
      "sponsor_class": "OTHER",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": null,
        "maximum_age": null,
        "sex": "ALL",
        "summary": "Not listed"
      },
      "enrollment_count": 86,
      "start_date": "2015-10-12",
      "completion_date": "2021-04",
      "has_results": false,
      "last_update_posted_date": "2021-07-28",
      "last_synced_at": "2026-09-30T11:06:51.226Z",
      "location_count": 1,
      "location_summary": "Cincinnati, Ohio",
      "locations": [
        {
          "city": "Cincinnati",
          "state": "Ohio"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT04368624"
    },
    {
      "nct_id": "NCT01135186",
      "title": "Impact of KUVAN® on Gastric Relaxation in Women With Diabetic Gastroparesis.",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "NA"
      ],
      "conditions": [
        "Gastroparesis"
      ],
      "interventions": [
        {
          "name": "sapropterin dihydrochloride",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "Stanford University",
      "sponsor_class": "OTHER",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": "65 Years",
        "sex": "FEMALE",
        "summary": "18 Years to 65 Years · Female only"
      },
      "enrollment_count": 9,
      "start_date": "2010-05",
      "completion_date": "2012-11",
      "has_results": true,
      "last_update_posted_date": "2019-09-10",
      "last_synced_at": "2026-09-30T11:06:51.226Z",
      "location_count": 1,
      "location_summary": "Stanford, California",
      "locations": [
        {
          "city": "Stanford",
          "state": "California"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT01135186"
    },
    {
      "nct_id": "NCT03136029",
      "title": "Exercise and NO in HFrEF",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "EARLY_PHASE1"
      ],
      "conditions": [
        "Heart Failure With Reduced Ejection Fraction"
      ],
      "interventions": [
        {
          "name": "Antioxidant",
          "type": "DIETARY_SUPPLEMENT"
        },
        {
          "name": "Tetrahydrobiopterin (BH4)",
          "type": "DIETARY_SUPPLEMENT"
        },
        {
          "name": "Exercise training",
          "type": "OTHER"
        }
      ],
      "intervention_types": [
        "DIETARY_SUPPLEMENT",
        "OTHER"
      ],
      "sponsor": "VA Office of Research and Development",
      "sponsor_class": "FED",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "18 Years and older"
      },
      "enrollment_count": 68,
      "start_date": "2018-06-01",
      "completion_date": "2025-07-31",
      "has_results": false,
      "last_update_posted_date": "2025-08-06",
      "last_synced_at": "2026-09-30T11:06:51.226Z",
      "location_count": 1,
      "location_summary": "Salt Lake City, Utah",
      "locations": [
        {
          "city": "Salt Lake City",
          "state": "Utah"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT03136029"
    },
    {
      "nct_id": "NCT01706965",
      "title": "Kuvan in People With Schizophrenia and Schizoaffective Disorder",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE1",
        "PHASE2"
      ],
      "conditions": [
        "Schizophrenia",
        "Schizoaffective Disorder"
      ],
      "interventions": [
        {
          "name": "Kuvan",
          "type": "DRUG"
        },
        {
          "name": "Multivitamin",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "New York State Psychiatric Institute",
      "sponsor_class": "OTHER",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": "64 Years",
        "sex": "ALL",
        "summary": "18 Years to 64 Years"
      },
      "enrollment_count": 27,
      "start_date": "2012-10",
      "completion_date": "2016-06",
      "has_results": true,
      "last_update_posted_date": "2017-09-13",
      "last_synced_at": "2026-09-30T11:06:51.226Z",
      "location_count": 1,
      "location_summary": "New York, New York",
      "locations": [
        {
          "city": "New York",
          "state": "New York"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT01706965"
    },
    {
      "nct_id": "NCT03680573",
      "title": "The Effect of Antioxidants on Skin Blood Flow-BH4",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE1"
      ],
      "conditions": [
        "Cardiovascular Diseases",
        "Cardiovascular Risk Factor",
        "Vasoconstriction"
      ],
      "interventions": [
        {
          "name": "Control: Lacated Ringers",
          "type": "DRUG"
        },
        {
          "name": "Apocynin",
          "type": "DRUG"
        },
        {
          "name": "Allopurinol",
          "type": "DRUG"
        },
        {
          "name": "BH4",
          "type": "DRUG"
        },
        {
          "name": "NG Nitro L Arginine Methyl Ester",
          "type": "DRUG"
        },
        {
          "name": "Sodium Nitroprusside",
          "type": "DRUG"
        },
        {
          "name": "Acetyl-ß-methylcholine chloride",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "The University of Texas at Arlington",
      "sponsor_class": "OTHER",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": "35 Years",
        "sex": "ALL",
        "summary": "18 Years to 35 Years"
      },
      "enrollment_count": 16,
      "start_date": "2018-01-08",
      "completion_date": "2018-05-05",
      "has_results": false,
      "last_update_posted_date": "2018-09-26",
      "last_synced_at": "2026-09-30T11:06:51.226Z",
      "location_count": 1,
      "location_summary": "Arlington, Texas",
      "locations": [
        {
          "city": "Arlington",
          "state": "Texas"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT03680573"
    },
    {
      "nct_id": "NCT01356966",
      "title": "Exercise Intolerance in Renal Failure",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE2"
      ],
      "conditions": [
        "Kidney Failure, Chronic"
      ],
      "interventions": [
        {
          "name": "Tetrahydrobiopterin",
          "type": "DRUG"
        },
        {
          "name": "Placebo",
          "type": "DRUG"
        },
        {
          "name": "Folate",
          "type": "DIETARY_SUPPLEMENT"
        }
      ],
      "intervention_types": [
        "DRUG",
        "DIETARY_SUPPLEMENT"
      ],
      "sponsor": "Emory University",
      "sponsor_class": "OTHER",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": "75 Years",
        "sex": "ALL",
        "summary": "18 Years to 75 Years"
      },
      "enrollment_count": 74,
      "start_date": "2011-05",
      "completion_date": "2014-05",
      "has_results": true,
      "last_update_posted_date": "2015-06-01",
      "last_synced_at": "2026-09-30T11:06:51.226Z",
      "location_count": 2,
      "location_summary": "Atlanta, Georgia • Decatur, Georgia",
      "locations": [
        {
          "city": "Atlanta",
          "state": "Georgia"
        },
        {
          "city": "Decatur",
          "state": "Georgia"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT01356966"
    },
    {
      "nct_id": "NCT00435331",
      "title": "6R-BH4 Pulmonary Arterial Hypertension Study",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE1"
      ],
      "conditions": [
        "Pulmonary Arterial Hypertension"
      ],
      "interventions": [
        {
          "name": "sapropterin dihydrochloride (6R-BH4)",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "Vanderbilt University",
      "sponsor_class": "OTHER",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "18 Years and older"
      },
      "enrollment_count": 14,
      "start_date": "2008-03",
      "completion_date": "2008-10",
      "has_results": false,
      "last_update_posted_date": "2013-06-19",
      "last_synced_at": "2026-09-30T11:06:51.226Z",
      "location_count": 1,
      "location_summary": "Nashville, Tennessee",
      "locations": [
        {
          "city": "Nashville",
          "state": "Tennessee"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT00435331"
    }
  ]
}