{
  "api_version": "1",
  "request": {
    "url": "https://clinicaltrialsfind.com/api/v1/search.json?intervention=Tetrahydrobiopterin",
    "query": {
      "intervention": "Tetrahydrobiopterin"
    },
    "page_size": 10
  },
  "pagination": {
    "page": 1,
    "page_size": 10,
    "total_count": 61,
    "total_pages": 7,
    "next_page_url": "https://clinicaltrialsfind.com/api/v1/search.json?intervention=Tetrahydrobiopterin&page=2&page_size=10",
    "previous_page_url": null
  },
  "source": "remote",
  "last_synced_at": "2026-09-21T17:30:51.170Z",
  "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": "NCT02774226",
      "title": "Long Term Nitric Oxide Bioavailability on Vascular Health in Chronic Obstructive Pulmonary Disease",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE2"
      ],
      "conditions": [
        "Chronic Obstructive Pulmonary Disease (COPD)"
      ],
      "interventions": [
        {
          "name": "Tetrahydrobiopterin (BH4)",
          "type": "DRUG"
        },
        {
          "name": "Antioxidant Cocktail",
          "type": "DIETARY_SUPPLEMENT"
        }
      ],
      "intervention_types": [
        "DRUG",
        "DIETARY_SUPPLEMENT"
      ],
      "sponsor": "Augusta University",
      "sponsor_class": "OTHER",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "18 Years and older"
      },
      "enrollment_count": 15,
      "start_date": "2015-09",
      "completion_date": "2018-07-30",
      "has_results": true,
      "last_update_posted_date": "2021-02-23",
      "last_synced_at": "2026-09-21T17:30:51.170Z",
      "location_count": 1,
      "location_summary": "Augusta, Georgia",
      "locations": [
        {
          "city": "Augusta",
          "state": "Georgia"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT02774226"
    },
    {
      "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": "2026-09-21T17:30:51.170Z",
      "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": "NCT00778206",
      "title": "PKUDOS: Phenylketonuria (PKU) Demographic, Outcomes, and Safety Registry",
      "overall_status": "COMPLETED",
      "study_type": "OBSERVATIONAL",
      "phases": [],
      "conditions": [
        "Phenylketonuria",
        "Hyperphenylalaninaemia"
      ],
      "interventions": [
        {
          "name": "Kuvan",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "BioMarin Pharmaceutical",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": null,
        "maximum_age": null,
        "sex": "ALL",
        "summary": "Not listed"
      },
      "enrollment_count": 1887,
      "start_date": "2008-09",
      "completion_date": "2021-01-29",
      "has_results": false,
      "last_update_posted_date": "2022-10-12",
      "last_synced_at": "2026-09-21T17:30:51.170Z",
      "location_count": 45,
      "location_summary": "Los Angeles, California • Orange, California • San Diego, California + 38 more",
      "locations": [
        {
          "city": "Los Angeles",
          "state": "California"
        },
        {
          "city": "Los Angeles",
          "state": "California"
        },
        {
          "city": "Los Angeles",
          "state": "California"
        },
        {
          "city": "Orange",
          "state": "California"
        },
        {
          "city": "San Diego",
          "state": "California"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT00778206"
    },
    {
      "nct_id": "NCT01114737",
      "title": "Safety and Therapeutic Effects of Sapropterin Dihydrochloride on Neuropsychiatric Symptoms in Phenylketonuria (PKU) Patients",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE3"
      ],
      "conditions": [
        "Phenylketonuria"
      ],
      "interventions": [
        {
          "name": "Sapropterin dihydrochloride",
          "type": "DRUG"
        },
        {
          "name": "Placebo",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "BioMarin Pharmaceutical",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "8 Years",
        "maximum_age": "65 Years",
        "sex": "ALL",
        "summary": "8 Years to 65 Years"
      },
      "enrollment_count": 206,
      "start_date": "2010-08",
      "completion_date": "2013-03",
      "has_results": true,
      "last_update_posted_date": "2016-02-01",
      "last_synced_at": "2026-09-21T17:30:51.170Z",
      "location_count": 26,
      "location_summary": "La Jolla, California • Los Angeles, California • Palo Alto, California + 23 more",
      "locations": [
        {
          "city": "La Jolla",
          "state": "California"
        },
        {
          "city": "Los Angeles",
          "state": "California"
        },
        {
          "city": "Palo Alto",
          "state": "California"
        },
        {
          "city": "San Francisco",
          "state": "California"
        },
        {
          "city": "Aurora",
          "state": "Colorado"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT01114737"
    },
    {
      "nct_id": "NCT00802893",
      "title": "Oral 6R-BH4 for the Treatment of Isolated Systolic Hypertension and Endothelial Dysfunction",
      "overall_status": "TERMINATED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE2"
      ],
      "conditions": [
        "Isolated Systolic Hypertension",
        "Endothelial Dysfunction"
      ],
      "interventions": [
        {
          "name": "6R-BH4",
          "type": "DRUG"
        },
        {
          "name": "Placebo",
          "type": "OTHER"
        }
      ],
      "intervention_types": [
        "DRUG",
        "OTHER"
      ],
      "sponsor": "Johns Hopkins University",
      "sponsor_class": "OTHER",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "40 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "40 Years and older"
      },
      "enrollment_count": 3,
      "start_date": "2008-12",
      "completion_date": "2009-05",
      "has_results": true,
      "last_update_posted_date": "2017-08-21",
      "last_synced_at": "2026-09-21T17:30:51.170Z",
      "location_count": 1,
      "location_summary": "Baltimore, Maryland",
      "locations": [
        {
          "city": "Baltimore",
          "state": "Maryland"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT00802893"
    },
    {
      "nct_id": "NCT02947750",
      "title": "Neurovascular Transduction During Exercise in Chronic Kidney Disease",
      "overall_status": "RECRUITING",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE2"
      ],
      "conditions": [
        "Renal Insufficiency, Chronic"
      ],
      "interventions": [
        {
          "name": "6R-BH4",
          "type": "DRUG"
        },
        {
          "name": "6R-BH4 placebo",
          "type": "OTHER"
        },
        {
          "name": "Folic acid",
          "type": "DIETARY_SUPPLEMENT"
        },
        {
          "name": "Exercise training",
          "type": "OTHER"
        },
        {
          "name": "Stretching",
          "type": "OTHER"
        },
        {
          "name": "Histidine and beta-alanine supplementation",
          "type": "DIETARY_SUPPLEMENT"
        },
        {
          "name": "Histidine and beta-alanine placebo",
          "type": "OTHER"
        }
      ],
      "intervention_types": [
        "DRUG",
        "OTHER",
        "DIETARY_SUPPLEMENT"
      ],
      "sponsor": "Emory University",
      "sponsor_class": "OTHER",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": "75 Years",
        "sex": "ALL",
        "summary": "18 Years to 75 Years"
      },
      "enrollment_count": 150,
      "start_date": "2016-10",
      "completion_date": "2027-04-30",
      "has_results": false,
      "last_update_posted_date": "2026-05-18",
      "last_synced_at": "2026-09-21T17:30:51.170Z",
      "location_count": 3,
      "location_summary": "Atlanta, Georgia • Decatur, Georgia",
      "locations": [
        {
          "city": "Atlanta",
          "state": "Georgia"
        },
        {
          "city": "Atlanta",
          "state": "Georgia"
        },
        {
          "city": "Decatur",
          "state": "Georgia"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT02947750"
    },
    {
      "nct_id": "NCT02530996",
      "title": "Systemic Sclerosis (SSc) Vasculopathy: Improved Clinical Monitoring and Treatment",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE1",
        "PHASE2"
      ],
      "conditions": [
        "Rheumatologic Disease"
      ],
      "interventions": [
        {
          "name": "BH4",
          "type": "DRUG"
        },
        {
          "name": "Vasculopathy assessment",
          "type": "DIAGNOSTIC_TEST"
        },
        {
          "name": "Placebo",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG",
        "DIAGNOSTIC_TEST"
      ],
      "sponsor": "VA Office of Research and Development",
      "sponsor_class": "FED",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": "95 Years",
        "sex": "ALL",
        "summary": "18 Years to 95 Years"
      },
      "enrollment_count": 12,
      "start_date": "2016-01-01",
      "completion_date": "2019-12-31",
      "has_results": true,
      "last_update_posted_date": "2021-04-05",
      "last_synced_at": "2026-09-21T17:30:51.170Z",
      "location_count": 1,
      "location_summary": "Salt Lake City, Utah",
      "locations": [
        {
          "city": "Salt Lake City",
          "state": "Utah"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT02530996"
    },
    {
      "nct_id": "NCT03519711",
      "title": "A Study of PTC923 (CNSA-001) in Primary Tetrahydrobiopterin (BH4) Deficient Participants With Hyperphenylalaninemia",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE1",
        "PHASE2"
      ],
      "conditions": [
        "BH4 Deficiency",
        "Hyperphenylalaninemia"
      ],
      "interventions": [
        {
          "name": "PTC923",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "PTC Therapeutics",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "12 Months",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "12 Months and older"
      },
      "enrollment_count": 8,
      "start_date": "2019-01-03",
      "completion_date": "2020-10-02",
      "has_results": true,
      "last_update_posted_date": "2023-11-14",
      "last_synced_at": "2026-09-21T17:30:51.170Z",
      "location_count": 4,
      "location_summary": "Minneapolis, Minnesota • Dallas, Texas • Salt Lake City, Utah + 1 more",
      "locations": [
        {
          "city": "Minneapolis",
          "state": "Minnesota"
        },
        {
          "city": "Dallas",
          "state": "Texas"
        },
        {
          "city": "Salt Lake City",
          "state": "Utah"
        },
        {
          "city": "Marshfield",
          "state": "Wisconsin"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT03519711"
    },
    {
      "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": "2026-09-21T17:30:51.170Z",
      "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": "NCT01772758",
      "title": "Cystic Fibrosis and Endothelial Function: At Rest and During Exercise",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE2"
      ],
      "conditions": [
        "Cystic Fibrosis"
      ],
      "interventions": [
        {
          "name": "BH4 5mg",
          "type": "DRUG"
        },
        {
          "name": "BH4 20mg",
          "type": "DRUG"
        },
        {
          "name": "Antioxidant Cocktail",
          "type": "DIETARY_SUPPLEMENT"
        }
      ],
      "intervention_types": [
        "DRUG",
        "DIETARY_SUPPLEMENT"
      ],
      "sponsor": "Augusta University",
      "sponsor_class": "OTHER",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "7 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "7 Years and older"
      },
      "enrollment_count": 64,
      "start_date": "2011-08",
      "completion_date": "2016-06-21",
      "has_results": true,
      "last_update_posted_date": "2019-06-20",
      "last_synced_at": "2026-09-21T17:30:51.170Z",
      "location_count": 1,
      "location_summary": "Augusta, Georgia",
      "locations": [
        {
          "city": "Augusta",
          "state": "Georgia"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT01772758"
    }
  ]
}