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ClinicalTrials.gov public records Last synced Sep 17, 2026, 2:51 AM EDT

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Showing 25–48 of 24 matching trials from the live ClinicalTrials.gov search.
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Filters: Intervention: Sapropterin Clear all
Completed Early Phase 1 Interventional

Exercise and NO in HFrEF

NCT03136029
View directory record Official record
Conditions
Heart Failure With Reduced Ejection Fraction
Interventions
Antioxidant, Tetrahydrobiopterin (BH4), Exercise training
Dietary Supplement · Other
Lead sponsor
VA Office of Research and Development
Federal
Eligibility
18 Years and older
Enrollment
68 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2018 – 2025
U.S. locations
1
States / cities
Salt Lake City, Utah
Source: ClinicalTrials.gov public record
Updated Aug 5, 2025 · Synced Sep 17, 2026, 2:51 AM EDT
Completed Phase 2 Interventional Results available

Endothelial Facilitation in Alzheimer's Disease

NCT01439555
View directory record Official record
Conditions
Alzheimer's Disease
Interventions
Simvastatin, L-Arginine, Tetrahydrobiopterin
Drug
Lead sponsor
University of Massachusetts, Worcester
Other
Eligibility
55 Years to 85 Years
Enrollment
11 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2011 – 2017
U.S. locations
1
States / cities
Worcester, Massachusetts
Source: ClinicalTrials.gov public record
Updated Jul 29, 2019 · Synced Sep 17, 2026, 2:51 AM EDT
Completed No phase listed Observational Accepts healthy volunteers

PKU Skin Stripping

NCT04368624
View directory record Official record
Conditions
Phenylketonurias
Interventions
Skin Tape, Blood Draw
Other · Diagnostic Test
Lead sponsor
Children's Hospital Medical Center, Cincinnati
Other
Eligibility
Not listed
Enrollment
86 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2015 – 2021
U.S. locations
1
States / cities
Cincinnati, Ohio
Source: ClinicalTrials.gov public record
Updated Jul 27, 2021 · Synced Sep 17, 2026, 2:51 AM EDT
Completed No phase listed Observational Accepts healthy volunteers

Evaluation of Behavior, Executive Function, Neurotransmitter Function and Genomic Expression Kuvan Nonresponders

NCT01274026
View directory record Official record
Conditions
Phenylketonuria, Behavior and Behavior Mechanisms, PAH Gene Expression
Interventions
sapropterin dihydrochloride
Drug
Lead sponsor
Tulane University School of Medicine
Other
Eligibility
2 Years to 21 Years
Enrollment
21 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2011 – 2013
U.S. locations
1
States / cities
New Orleans, Louisiana
Source: ClinicalTrials.gov public record
Updated Aug 13, 2023 · Synced Sep 17, 2026, 2:51 AM EDT
Completed Not applicable Interventional Results available

Rhode Island Diastolic Dysfunction - Heart Failure

NCT02353312
View directory record Official record
Conditions
Heart Failure, Cardiovascular Disease
Interventions
Kuvan
Drug
Lead sponsor
Providence VA Medical Center
Federal
Eligibility
18 Years and older
Enrollment
28 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2015 – 2018
U.S. locations
1
States / cities
Providence, Rhode Island
Source: ClinicalTrials.gov public record
Updated Jul 2, 2025 · Synced Sep 17, 2026, 2:51 AM EDT
Completed Phase 2 Interventional Results available

Tetrahydrobiopterin in Patients With Chronic Kidney Disease (CKD) and Albuminuria

NCT00625820
View directory record Official record
Conditions
Kidney Disease, Albuminuria
Interventions
6R BH4, Vitamin C
Drug · Dietary Supplement
Lead sponsor
University of Michigan
Other
Eligibility
18 Years to 75 Years
Enrollment
17 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2008
U.S. locations
1
States / cities
Ann Arbor, Michigan
Source: ClinicalTrials.gov public record
Updated Oct 17, 2016 · Synced Sep 17, 2026, 2:51 AM EDT
Completed Phase 2 Interventional Accepts healthy volunteers Results available

Long Term Nitric Oxide Bioavailability on Vascular Health in Chronic Obstructive Pulmonary Disease

NCT02774226
View directory record Official record
Conditions
Chronic Obstructive Pulmonary Disease (COPD)
Interventions
Tetrahydrobiopterin (BH4), Antioxidant Cocktail
Drug · Dietary Supplement
Lead sponsor
Augusta University
Other
Eligibility
18 Years and older
Enrollment
15 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2015 – 2018
U.S. locations
1
States / cities
Augusta, Georgia
Source: ClinicalTrials.gov public record
Updated Feb 22, 2021 · Synced Sep 17, 2026, 2:51 AM EDT
Completed Phase 4 Interventional Results available

The Effectiveness of Kuvan in Amish PKU Patients

NCT02677870
View directory record Official record
Conditions
Phenylketonuria
Interventions
saproterin dihydrochloride, Diet treatment
Drug · Other
Lead sponsor
University Hospitals Cleveland Medical Center
Other
Eligibility
2 Years to 60 Years
Enrollment
7 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2018 – 2019
U.S. locations
1
States / cities
Cleveland, Ohio
Source: ClinicalTrials.gov public record
Updated Apr 26, 2022 · Synced Sep 17, 2026, 2:51 AM EDT
Completed Phase 4 Interventional Results available

Effects of Kuvan on Melatonin Secretion

NCT01617070
View directory record Official record
Conditions
Phenylketonuria (PKU)
Interventions
Kuvan, Large Neutral Amino Acid Therapy
Drug · Dietary Supplement
Lead sponsor
University of Southern California
Other
Eligibility
18 Years and older
Enrollment
10 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2012 – 2014
U.S. locations
1
States / cities
Los Angeles, California
Source: ClinicalTrials.gov public record
Updated Nov 17, 2016 · Synced Sep 17, 2026, 2:51 AM EDT
Completed Phase 1Phase 2 Interventional Accepts healthy volunteers Results available

Systemic Sclerosis (SSc) Vasculopathy: Improved Clinical Monitoring and Treatment

NCT02530996
View directory record Official record
Conditions
Rheumatologic Disease
Interventions
BH4, Vasculopathy assessment, Placebo
Drug · Diagnostic Test
Lead sponsor
VA Office of Research and Development
Federal
Eligibility
18 Years to 95 Years
Enrollment
12 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2016 – 2019
U.S. locations
1
States / cities
Salt Lake City, Utah
Source: ClinicalTrials.gov public record
Updated Apr 4, 2021 · Synced Sep 17, 2026, 2:51 AM EDT
Withdrawn Phase 2 Interventional

L-arginine Study for Persistent Symptoms of Schizophrenia

NCT04054973
View directory record Official record
Conditions
Schizo Affective Disorder, Schizophrenia
Interventions
L-arginine, Sapropterin Dihydrochloride
Drug
Lead sponsor
University of Massachusetts, Worcester
Other
Eligibility
18 Years to 65 Years
Healthy volunteers
Healthy volunteers not accepted
Timeline
2019 – 2021
U.S. locations
1
States / cities
Worcester, Massachusetts
Source: ClinicalTrials.gov public record
Updated Jan 19, 2022 · Synced Sep 17, 2026, 2:51 AM EDT
Completed No phase listed Observational Accepts healthy volunteers

The Brain and Neuropsychological Functioning in Adults With Sapropterin Dihydrochloride Treated Phenylketonuria

NCT02297347
View directory record Official record
Conditions
Phenylketonuria
Interventions
Not listed
Lead sponsor
Boston Children's Hospital
Other
Eligibility
18 Years to 55 Years
Enrollment
10 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2015 – 2017
U.S. locations
1
States / cities
Boston, Massachusetts
Source: ClinicalTrials.gov public record
Updated Feb 4, 2018 · Synced Sep 17, 2026, 2:51 AM EDT
Completed Phase 2Phase 3 Interventional Results available

Open-Label Extension Study of Kuvan for Autism

NCT00943579
View directory record Official record
Conditions
Autistic Disorder
Interventions
Kuvan®
Drug
Lead sponsor
The Children's Health Council
Other
Eligibility
3 Years to 6 Years
Enrollment
41 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2009 – 2012
U.S. locations
1
States / cities
Palo Alto, California
Source: ClinicalTrials.gov public record
Updated May 1, 2018 · Synced Sep 17, 2026, 2:51 AM EDT
Completed Not applicable Interventional Results available

Tetrahydrobiopterin Treatment in Children With Idiopathic Cognitive Developmental Disorders

NCT01141595
View directory record Official record
Conditions
Autism Spectrum Disorder
Interventions
sapropterin dihydrochloride
Drug
Lead sponsor
The University of Texas Health Science Center, Houston
Other
Eligibility
2 Years to 6 Years
Enrollment
10 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2010 – 2011
U.S. locations
1
States / cities
Little Rock, Arkansas
Source: ClinicalTrials.gov public record
Updated Mar 31, 2014 · Synced Sep 17, 2026, 2:51 AM EDT
Approved For Marketing No phase listed Expanded access

Sapropterin Expanded Access Program

NCT00484991
View directory record Official record
Conditions
Phenylketonuria
Interventions
Sapropterin dihydrochloride
Drug
Lead sponsor
BioMarin Pharmaceutical
Industry
Eligibility
9 Years and older
U.S. locations
36
States / cities
Los Angeles, California • Orange, California • San Diego, California + 33 more
Source: ClinicalTrials.gov public record
Updated Apr 14, 2008 · Synced Sep 17, 2026, 2:51 AM EDT
Completed Phase 2 Interventional

A Study of the Effects of 6R-BH4 on Blood Pressure in Subjects With Poorly Controlled Systemic Hypertension

NCT00325962
View directory record Official record
Conditions
Hypertension
Interventions
6R-BH4 (sapropterin dihydrochloride)
Drug
Lead sponsor
BioMarin Pharmaceutical
Industry
Eligibility
18 Years and older
Enrollment
84 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2006 – 2008
U.S. locations
24
States / cities
Hoover, Alabama • Huntsville, Alabama • Mobile, Alabama + 21 more
Source: ClinicalTrials.gov public record
Updated Jul 20, 2009 · Synced Sep 17, 2026, 2:51 AM EDT
Completed Phase 2 Interventional Results available

Kuvan Therapy in Phenylketonuria (PKU): The Effect of Blood Phenylalanine Concentration on Kuvan Response

NCT00841100
View directory record Official record
Conditions
Phenylketonuria
Interventions
Kuvan, Diet
Drug · Other
Lead sponsor
University of Miami
Other
Eligibility
4 Years and older
Enrollment
21 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2008 – 2011
U.S. locations
1
States / cities
Miami, Florida
Source: ClinicalTrials.gov public record
Updated Dec 2, 2019 · Synced Sep 17, 2026, 2:51 AM EDT
Completed Phase 2 Interventional Results available

A Phase 2 Study of the Effects of Sapropterin Dihydrochloride on Symptomatic Peripheral Arterial Disease

NCT00403494
View directory record Official record
Conditions
Intermittent Claudication
Interventions
Placebo, Sapropterin Dihydrochloride
Other · Drug
Lead sponsor
BioMarin Pharmaceutical
Industry
Eligibility
40 Years to 80 Years
Enrollment
190 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2006 – 2009
U.S. locations
17
States / cities
Scottsdale, Arizona • Sacramento, California • San Diego, California + 14 more
Source: ClinicalTrials.gov public record
Updated Jan 6, 2021 · Synced Sep 17, 2026, 2:51 AM EDT
Completed No phase listed Observational Accepts healthy volunteers

Sapropterin in Individuals With Phenylketonuria

NCT00730080
View directory record Official record
Conditions
Phenylketonuria
Interventions
Sapropterin (Kuvan)
Drug
Lead sponsor
Washington University School of Medicine
Other
Eligibility
6 Years to 50 Years
Enrollment
45 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2008 – 2018
U.S. locations
1
States / cities
St Louis, Missouri
Source: ClinicalTrials.gov public record
Updated Jun 17, 2018 · Synced Sep 17, 2026, 2:51 AM EDT
Terminated Not applicable Interventional Accepts healthy volunteers Results available

Bone Mineral Density in Adults With Hyperphenylalaninemia on Kuvan Therapy

NCT01541397
View directory record Official record
Conditions
Hyperphenylalaninemia, Phenylketonuria
Interventions
Sapropterin
Drug
Lead sponsor
The University of Texas Health Science Center, Houston
Other
Eligibility
18 Years to 50 Years
Enrollment
6 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2011 – 2012
U.S. locations
1
States / cities
Houston, Texas
Source: ClinicalTrials.gov public record
Updated Jul 6, 2015 · Synced Sep 17, 2026, 2:51 AM EDT
Recruiting Phase 1 Interventional

Novel Approaches for Improving Vascular Function in Veterans With HFpEF

NCT06312748
View directory record Official record
Conditions
Heart Failure With Preserved Ejection Fraction, Inflammation
Interventions
L-Citrulline, Placebo for L-Citrulline, BH4, Placebo for BH4, Atorvastatin, Placebo for Atorvastatin
Drug
Lead sponsor
VA Office of Research and Development
Federal
Eligibility
18 Years and older
Enrollment
90 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2021 – 2030
U.S. locations
1
States / cities
Salt Lake City, Utah
Source: ClinicalTrials.gov public record
Updated Apr 22, 2026 · Synced Sep 17, 2026, 2:51 AM EDT
Completed Phase 2 Interventional Accepts healthy volunteers Results available

Exercise Intolerance in Renal Failure

NCT01356966
View directory record Official record
Conditions
Kidney Failure, Chronic
Interventions
Tetrahydrobiopterin, Placebo, Folate
Drug · Dietary Supplement
Lead sponsor
Emory University
Other
Eligibility
18 Years to 75 Years
Enrollment
74 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2011 – 2014
U.S. locations
2
States / cities
Atlanta, Georgia • Decatur, Georgia
Source: ClinicalTrials.gov public record
Updated May 31, 2015 · Synced Sep 17, 2026, 2:51 AM EDT
Completed Phase 3 Interventional Results available

Study to Evaluate the Safety and Efficacy of Phenoptin™ in Subjects With Phenylketonuria Who Have Elevated Phenylalanine Levels

NCT00104247
View directory record Official record
Conditions
Phenylketonurias
Interventions
sapropterin dihydrochloride, 6R-BH4, tetrahydrobiopterin
Drug
Lead sponsor
BioMarin Pharmaceutical
Industry
Eligibility
8 Years and older
Enrollment
89 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2005 – 2006
U.S. locations
13
States / cities
Los Angeles, California • Oakland, California • New Haven, Connecticut + 10 more
Source: ClinicalTrials.gov public record
Updated Jul 22, 2014 · Synced Sep 17, 2026, 2:51 AM EDT
Withdrawn Phase 1 Interventional Accepts healthy volunteers

O2 Transport and Utilization in Health and Lung Disease

NCT04014712
View directory record Official record
Conditions
COPD, Tetrahydrobiopterin Deficiency, Oxidative Stress
Interventions
Tetrahydrobiopterin, Placebo oral tablet
Drug
Lead sponsor
University of Massachusetts, Amherst
Other
Eligibility
18 Years to 85 Years
Healthy volunteers
Accepts healthy volunteers
Timeline
2021 – 2022
U.S. locations
1
States / cities
Amherst, Massachusetts
Source: ClinicalTrials.gov public record
Updated Dec 18, 2023 · Synced Sep 17, 2026, 2:51 AM EDT