A Study of the Effects of 6R-BH4 on Blood Pressure in Subjects With Poorly Controlled Systemic Hypertension
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ClinicalTrials.gov Identifier: NCT00325962 |
Recruitment Status :
Completed
First Posted : May 15, 2006
Last Update Posted : July 21, 2009
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Condition or disease | Intervention/treatment | Phase |
---|---|---|
Hypertension | Drug: 6R-BH4 (sapropterin dihydrochloride) | Phase 2 |
Study Type : | Interventional (Clinical Trial) |
Enrollment : | 84 participants |
Allocation: | Randomized |
Intervention Model: | Parallel Assignment |
Masking: | Double |
Primary Purpose: | Treatment |
Official Title: | A Phase 2, Multicenter, Randomized, Double-blind, Placebo-controlled, Parallel Study of the Effects of 6R-BH4 on Blood Pressure in Subjects With Poorly Controlled Systemic Hypertension |
Study Start Date : | May 2006 |
Actual Primary Completion Date : | December 2006 |
Actual Study Completion Date : | December 2008 |

- To compare oral 6R-BH4 to placebo with respect to change from baseline in arterial systolic blood pressure after 8 weeks of treatment in subjects with poorly controlled hypertension.
- To compare oral 6R-BH4 to placebo with respect to change from baseline in arterial diastolic blood pressure after 8 weeks of treatment in subjects with poorly controlled hypertension
- To compare oral 6R-BH4 to placebo with respect to change from baseline in insulin sensitivity after 8 weeks of treatment in subjects with both type 2 diabetes and poorly controlled hypertension
- To compare oral 6R-BH4 to placebo with respect to change from baseline in eNOS activity and endothelial dysfunction after 8 weeks of treatment in subjects with poorly controlled hypertension
- To assess the safety of oral dosing of 6R-BH4 in subjects with poorly controlled hypertension

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Ages Eligible for Study: | 18 Years and older (Adult, Older Adult) |
Sexes Eligible for Study: | All |
Accepts Healthy Volunteers: | No |
Inclusion Criteria:
- Willing and able to provide written, signed informed consent after the nature of the study has been explained and prior to any research-related procedures.
- At least 18 years of age.
- Willing and able to comply with all study-related procedures.
- History of documented essential hypertension (BP greater than or equal to 140 mm Hg systolic and/or 90 mm Hg diastolic measured on 2 separate occasions).
- Have poorly controlled hypertension despite use of at least two conventional antihypertensive agents with different mechanisms of action taken concurrently and consistently for at least 3 months before randomization. (Note: Antihypertensive agents may be individual or combined into a single medication.)
- During the two-week screening period, mean SBP and mean DBP fall within the following ranges:
- Mean SBP between 135 and 160 mm Hg
- Mean DBP between 85 and 110 mm Hg
- Sexually active subjects must be willing to use an acceptable method of contraception while participating in the study.
- Females of childbearing potential must have a negative pregnancy test at screening and be willing to have additional pregnancy tests during this study.
Individuals in the diabetic cohort must meet this additional criterion:
- Documented history of type 2 diabetes that has been treated using the same therapy for at least 3 months.
Exclusion Criteria:
- Previous treatment with any formulation of BH4.
- Known allergy or hypersensitivity to any excipient of 6R-BH4.
- Known secondary cause for hypertension.
- Concurrent disease or condition that would interfere with study participation or safety such as bleeding disorders, history of syncope or vertigo, severe gastrointestinal reflux disease (GERD), symptomatic coronary or peripheral vascular disease, arrhythmia, organ transplant, organ failure, or type 1 diabetes mellitus.
- Any sever co-morbid condition that would limit life expectancy to less than 6 months.
- Serum creatinine >2.0mg/dL or hepatic enzyme levels more than 2 times the upper limit of normal.
- Requirement for concomitant treatment with any drug known to inhibit folate metabolism (e.g., methotrexate).
- Concomitant treatment with levodopa.
- Concomitant treatment with any phosphodiesterase (PDE) 5 inhibitor (e.g., Viagra(R), Cialis(R), or Levitra(R), or Revatio (TM) or any PDE 3 inhibitor (e.g., cilostazol, milrinone, or vesnarinone).)
- Use of any investigational product or device within 30 days prior to screening, or requirement for any investigational agent prior to completion of all scheduled study assessments.
- Pregnant or breastfeeding at screening or planning to become pregnant (subject or partner) at any time during study.

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT00325962
United States, Alabama | |
Hoover, Alabama, United States | |
Huntsville, Alabama, United States | |
Mobile, Alabama, United States | |
Muscle Shoals, Alabama, United States | |
United States, Arizona | |
Gilbert, Arizona, United States | |
Phoenix, Arizona, United States | |
United States, California | |
Anaheim, California, United States | |
Burbank, California, United States | |
Cudahy, California, United States | |
Long Beach, California, United States | |
Roseville, California, United States | |
San Francisco, California, United States | |
United States, Colorado | |
Denver, Colorado, United States | |
United States, Florida | |
Pembroke Pines, Florida, United States | |
United States, Georgia | |
Atlanta, Georgia, United States | |
Decatur, Georgia, United States | |
United States, Indiana | |
Indianapolis, Indiana, United States | |
United States, Maine | |
Auburn, Maine, United States | |
Scarborough, Maine, United States | |
United States, Maryland | |
Baltimore, Maryland, United States | |
United States, North Carolina | |
Charlotte, North Carolina, United States | |
United States, Ohio | |
Cincinnati, Ohio, United States | |
United States, Tennessee | |
Knoxville, Tennessee, United States | |
United States, Texas | |
Carrollton, Texas, United States |
Study Director: | Martha Nicholson, MD | BioMarin Pharmaceutical |
ClinicalTrials.gov Identifier: | NCT00325962 |
Other Study ID Numbers: |
HTN-001 |
First Posted: | May 15, 2006 Key Record Dates |
Last Update Posted: | July 21, 2009 |
Last Verified: | July 2009 |
Hypertension Type 2 Diabetes 6R-BH4 BH4 BH4 deficiency |
sapropterin dihydrochloride endothelial dysfunction NO Nitric Oxide |
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Membrane Transport Modulators Molecular Mechanisms of Pharmacological Action Calcium-Regulating Hormones and Agents Physiological Effects of Drugs Vasodilator Agents |