{
  "api_version": "1",
  "request": {
    "url": "https://clinicaltrialsfind.com/api/v1/search.json?intervention=Tetrahydrobiopterin+10+mg%2Fkg",
    "query": {
      "intervention": "Tetrahydrobiopterin 10 mg/kg"
    },
    "page_size": 10
  },
  "pagination": {
    "page": 1,
    "page_size": 10,
    "total_count": 9,
    "total_pages": 1,
    "next_page_url": null,
    "previous_page_url": null
  },
  "source": "remote",
  "last_synced_at": "2026-10-06T14:03:14.846Z",
  "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": "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      "overall_status": "WITHDRAWN",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": "2026-10-06T14:03:14.846Z",
      "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": "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": "2026-10-06T14:03:14.846Z",
      "location_count": 1,
      "location_summary": "Worcester, Massachusetts",
      "locations": [
        {
          "city": "Worcester",
          "state": "Massachusetts"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT04800692"
    },
    {
      "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": "2026-10-06T14:03:14.846Z",
      "location_count": 1,
      "location_summary": "Salt Lake City, Utah",
      "locations": [
        {
          "city": "Salt Lake City",
          "state": "Utah"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT06312748"
    },
    {
      "nct_id": "NCT04014712",
      "title": "O2 Transport and Utilization in Health and Lung Disease",
      "overall_status": "WITHDRAWN",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE1"
      ],
      "conditions": [
        "COPD",
        "Tetrahydrobiopterin Deficiency",
        "Oxidative Stress"
      ],
      "interventions": [
        {
          "name": "Tetrahydrobiopterin",
          "type": "DRUG"
        },
        {
          "name": "Placebo oral tablet",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "University of Massachusetts, Amherst",
      "sponsor_class": "OTHER",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": "85 Years",
        "sex": "ALL",
        "summary": "18 Years to 85 Years"
      },
      "enrollment_count": 0,
      "start_date": "2021-04",
      "completion_date": "2022-08",
      "has_results": false,
      "last_update_posted_date": "2023-12-19",
      "last_synced_at": "2026-10-06T14:03:14.846Z",
      "location_count": 1,
      "location_summary": "Amherst, Massachusetts",
      "locations": [
        {
          "city": "Amherst",
          "state": "Massachusetts"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT04014712"
    },
    {
      "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": "2026-10-06T14:03:14.846Z",
      "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": "NCT00841100",
      "title": "Kuvan Therapy in Phenylketonuria (PKU): The Effect of Blood Phenylalanine Concentration on Kuvan Response",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE2"
      ],
      "conditions": [
        "Phenylketonuria"
      ],
      "interventions": [
        {
          "name": "Kuvan",
          "type": "DRUG"
        },
        {
          "name": "Diet",
          "type": "OTHER"
        }
      ],
      "intervention_types": [
        "DRUG",
        "OTHER"
      ],
      "sponsor": "University of Miami",
      "sponsor_class": "OTHER",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "4 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "4 Years and older"
      },
      "enrollment_count": 21,
      "start_date": "2008-12",
      "completion_date": "2011-07-19",
      "has_results": true,
      "last_update_posted_date": "2019-12-03",
      "last_synced_at": "2026-10-06T14:03:14.846Z",
      "location_count": 1,
      "location_summary": "Miami, Florida",
      "locations": [
        {
          "city": "Miami",
          "state": "Florida"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT00841100"
    },
    {
      "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": "2026-10-06T14:03:14.846Z",
      "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": "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": "2026-10-06T14:03:14.846Z",
      "location_count": 1,
      "location_summary": "Nashville, Tennessee",
      "locations": [
        {
          "city": "Nashville",
          "state": "Tennessee"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT00435331"
    },
    {
      "nct_id": "NCT00445978",
      "title": "A Phase 2 Study of the Effects of 6R-BH4 in Subjects With Sickle Cell Disease",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE2"
      ],
      "conditions": [
        "Sickle Cell Disease"
      ],
      "interventions": [
        {
          "name": "Sapropterin Dihydrochloride",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "BioMarin Pharmaceutical",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "15 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "15 Years and older"
      },
      "enrollment_count": 32,
      "start_date": "2007-05",
      "completion_date": "2009-06",
      "has_results": true,
      "last_update_posted_date": "2021-02-25",
      "last_synced_at": "2026-10-06T14:03:14.846Z",
      "location_count": 12,
      "location_summary": "Washington D.C., District of Columbia • Augusta, Georgia • Savannah, Georgia + 9 more",
      "locations": [
        {
          "city": "Washington D.C.",
          "state": "District of Columbia"
        },
        {
          "city": "Augusta",
          "state": "Georgia"
        },
        {
          "city": "Savannah",
          "state": "Georgia"
        },
        {
          "city": "Indianapolis",
          "state": "Indiana"
        },
        {
          "city": "Detroit",
          "state": "Michigan"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT00445978"
    }
  ]
}