{
  "api_version": "1",
  "request": {
    "url": "https://clinicaltrialsfind.com/api/v1/search.json?intervention=Tetrahydrobiopterin+20+mg%2Fkg",
    "query": {
      "intervention": "Tetrahydrobiopterin 20 mg/kg"
    },
    "page_size": 10
  },
  "pagination": {
    "page": 1,
    "page_size": 10,
    "total_count": 22,
    "total_pages": 3,
    "next_page_url": "https://clinicaltrialsfind.com/api/v1/search.json?intervention=Tetrahydrobiopterin+20+mg%2Fkg&page=2&page_size=10",
    "previous_page_url": null
  },
  "source": "remote",
  "last_synced_at": "2026-10-06T14:02:04.816Z",
  "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": "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": "2026-10-06T14:02:04.816Z",
      "location_count": 1,
      "location_summary": "Augusta, Georgia",
      "locations": [
        {
          "city": "Augusta",
          "state": "Georgia"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT01772758"
    },
    {
      "nct_id": "NCT01412437",
      "title": "Neuroimaging and Neurocognitive Assessment and Response to Sapropterin Dihydrochloride Treatment in Phenylketonuria",
      "overall_status": "WITHDRAWN",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "NA"
      ],
      "conditions": [
        "PKU"
      ],
      "interventions": [
        {
          "name": "diet",
          "type": "DIETARY_SUPPLEMENT"
        },
        {
          "name": "sapropterin dihydrochloride",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DIETARY_SUPPLEMENT",
        "DRUG"
      ],
      "sponsor": "Children's National Research Institute",
      "sponsor_class": "OTHER",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": "40 Years",
        "sex": "ALL",
        "summary": "18 Years to 40 Years"
      },
      "enrollment_count": 0,
      "start_date": "2011-04",
      "completion_date": "2012-12",
      "has_results": false,
      "last_update_posted_date": "2014-12-17",
      "last_synced_at": "2026-10-06T14:02:04.816Z",
      "location_count": 1,
      "location_summary": "Washington D.C., District of Columbia",
      "locations": [
        {
          "city": "Washington D.C.",
          "state": "District of Columbia"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT01412437"
    },
    {
      "nct_id": "NCT01806051",
      "title": "A Pilot Study on Diurnal Variation",
      "overall_status": "TERMINATED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "NA"
      ],
      "conditions": [
        "Phenylketonuria (PKU)"
      ],
      "interventions": [
        {
          "name": "Kuvan",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "Dr. Linda Randolph",
      "sponsor_class": "OTHER",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "4 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "4 Years and older"
      },
      "enrollment_count": 6,
      "start_date": "2013-03",
      "completion_date": "2014-05",
      "has_results": true,
      "last_update_posted_date": "2016-04-20",
      "last_synced_at": "2026-10-06T14:02:04.816Z",
      "location_count": 1,
      "location_summary": "Los Angeles, California",
      "locations": [
        {
          "city": "Los Angeles",
          "state": "California"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT01806051"
    },
    {
      "nct_id": "NCT01617070",
      "title": "Effects of Kuvan on Melatonin Secretion",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE4"
      ],
      "conditions": [
        "Phenylketonuria (PKU)"
      ],
      "interventions": [
        {
          "name": "Kuvan",
          "type": "DRUG"
        },
        {
          "name": "Large Neutral Amino Acid Therapy",
          "type": "DIETARY_SUPPLEMENT"
        }
      ],
      "intervention_types": [
        "DRUG",
        "DIETARY_SUPPLEMENT"
      ],
      "sponsor": "University of Southern California",
      "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": "2012-05",
      "completion_date": "2014-12",
      "has_results": true,
      "last_update_posted_date": "2016-11-18",
      "last_synced_at": "2026-10-06T14:02:04.816Z",
      "location_count": 1,
      "location_summary": "Los Angeles, California",
      "locations": [
        {
          "city": "Los Angeles",
          "state": "California"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT01617070"
    },
    {
      "nct_id": "NCT00838435",
      "title": "Effect of Kuvan on Neurocognitive Function, Blood Phenylalanine Level, Safety, and Pharmacokinetics in Children With PKU",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE3"
      ],
      "conditions": [
        "Phenylketonuria"
      ],
      "interventions": [
        {
          "name": "sapropterin dihydrochloride",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "BioMarin Pharmaceutical",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": null,
        "maximum_age": "6 Years",
        "sex": "ALL",
        "summary": "Up to 6 Years"
      },
      "enrollment_count": 95,
      "start_date": "2009-02",
      "completion_date": "2018-09-14",
      "has_results": true,
      "last_update_posted_date": "2020-12-22",
      "last_synced_at": "2026-10-06T14:02:04.816Z",
      "location_count": 12,
      "location_summary": "La Jolla, California • Orange, California • Tampa, Florida + 9 more",
      "locations": [
        {
          "city": "La Jolla",
          "state": "California"
        },
        {
          "city": "Orange",
          "state": "California"
        },
        {
          "city": "Tampa",
          "state": "Florida"
        },
        {
          "city": "Chicago",
          "state": "Illinois"
        },
        {
          "city": "Boston",
          "state": "Massachusetts"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT00838435"
    },
    {
      "nct_id": "NCT01439555",
      "title": "Endothelial Facilitation in Alzheimer's Disease",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE2"
      ],
      "conditions": [
        "Alzheimer's Disease"
      ],
      "interventions": [
        {
          "name": "Simvastatin",
          "type": "DRUG"
        },
        {
          "name": "L-Arginine",
          "type": "DRUG"
        },
        {
          "name": "Tetrahydrobiopterin",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "University of Massachusetts, Worcester",
      "sponsor_class": "OTHER",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "55 Years",
        "maximum_age": "85 Years",
        "sex": "ALL",
        "summary": "55 Years to 85 Years"
      },
      "enrollment_count": 11,
      "start_date": "2011-11",
      "completion_date": "2017-11",
      "has_results": true,
      "last_update_posted_date": "2019-07-30",
      "last_synced_at": "2026-10-06T14:02:04.816Z",
      "location_count": 1,
      "location_summary": "Worcester, Massachusetts",
      "locations": [
        {
          "city": "Worcester",
          "state": "Massachusetts"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT01439555"
    },
    {
      "nct_id": "NCT04800692",
      "title": "The Effects of ATLAS Therapy on Nitric Oxide Bioavailability in Patients With Intermittent Claudication",
      "overall_status": "ACTIVE_NOT_RECRUITING",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE1"
      ],
      "conditions": [
        "Claudication, Intermittent",
        "Peripheral Artery Disease",
        "Peripheral Vascular Diseases"
      ],
      "interventions": [
        {
          "name": "Tetrahydrobiopterin 10 mg/kg",
          "type": "DRUG"
        },
        {
          "name": "Tetrahydrobiopterin 20 mg/kg",
          "type": "DRUG"
        },
        {
          "name": "L-Ascorbate",
          "type": "DRUG"
        },
        {
          "name": "L-Arginine",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "Louis Messina",
      "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": "2021-06-15",
      "completion_date": "2027-12",
      "has_results": false,
      "last_update_posted_date": "2026-04-15",
      "last_synced_at": "2026-10-06T14:02:04.816Z",
      "location_count": 1,
      "location_summary": "Worcester, Massachusetts",
      "locations": [
        {
          "city": "Worcester",
          "state": "Massachusetts"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT04800692"
    },
    {
      "nct_id": "NCT00986973",
      "title": "Fluorodeoxyglucose Positron Emission Tomography (FDG PET) Findings in Patients With Phenylketonuria Before and After KUVAN Therapy",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "NA"
      ],
      "conditions": [
        "Phenylketonuria"
      ],
      "interventions": [
        {
          "name": "Sapropterin",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "Children's Hospital of Philadelphia",
      "sponsor_class": "OTHER",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": "50 Years",
        "sex": "ALL",
        "summary": "18 Years to 50 Years"
      },
      "enrollment_count": 6,
      "start_date": "2010-03",
      "completion_date": "2011-09",
      "has_results": true,
      "last_update_posted_date": "2015-06-08",
      "last_synced_at": "2026-10-06T14:02:04.816Z",
      "location_count": 1,
      "location_summary": "Philadelphia, Pennsylvania",
      "locations": [
        {
          "city": "Philadelphia",
          "state": "Pennsylvania"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT00986973"
    },
    {
      "nct_id": "NCT01141595",
      "title": "Tetrahydrobiopterin Treatment in Children With Idiopathic Cognitive Developmental Disorders",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "NA"
      ],
      "conditions": [
        "Autism Spectrum Disorder"
      ],
      "interventions": [
        {
          "name": "sapropterin dihydrochloride",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "The University of Texas Health Science Center, Houston",
      "sponsor_class": "OTHER",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "2 Years",
        "maximum_age": "6 Years",
        "sex": "ALL",
        "summary": "2 Years to 6 Years"
      },
      "enrollment_count": 10,
      "start_date": "2010-07",
      "completion_date": "2011-09",
      "has_results": true,
      "last_update_posted_date": "2014-04-01",
      "last_synced_at": "2026-10-06T14:02:04.816Z",
      "location_count": 1,
      "location_summary": "Little Rock, Arkansas",
      "locations": [
        {
          "city": "Little Rock",
          "state": "Arkansas"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT01141595"
    },
    {
      "nct_id": "NCT06312748",
      "title": "Novel Approaches for Improving Vascular Function in Veterans With HFpEF",
      "overall_status": "RECRUITING",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE1"
      ],
      "conditions": [
        "Heart Failure With Preserved Ejection Fraction",
        "Inflammation"
      ],
      "interventions": [
        {
          "name": "L-Citrulline",
          "type": "DRUG"
        },
        {
          "name": "Placebo for L-Citrulline",
          "type": "DRUG"
        },
        {
          "name": "BH4",
          "type": "DRUG"
        },
        {
          "name": "Placebo for BH4",
          "type": "DRUG"
        },
        {
          "name": "Atorvastatin",
          "type": "DRUG"
        },
        {
          "name": "Placebo for Atorvastatin",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "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": 90,
      "start_date": "2021-05-19",
      "completion_date": "2030-09-30",
      "has_results": false,
      "last_update_posted_date": "2026-04-23",
      "last_synced_at": "2026-10-06T14:02:04.816Z",
      "location_count": 1,
      "location_summary": "Salt Lake City, Utah",
      "locations": [
        {
          "city": "Salt Lake City",
          "state": "Utah"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT06312748"
    }
  ]
}