Effect of 6R-BH4 Treatment in Coronary Artery Disease (OXBIO Study)

A Randomised, Placebo-Controlled Study of Two Doses of Oral 6R-BH4 on Vascular Function in Subjects With Coronary Artery Disease

Status

UNKNOWN

Phases

Phase 2

Study type

Interventional

Source

ClinicalTrials.gov

Registry ID

NCT00423280

Enrollment

Registered

2007-01-18

Start date

2006-11-30

Completion date

2009-02-28

Last updated

2008-08-07

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Coronary Artery Disease

Keywords

Endothelium, Nitric Oxide, Magnetic Resonance Imaging, Tetrahydrobiopterin

Brief summary

The purpose of this study is to determine the effect of 6R-BH4 on vascular function in patients with coronary artery disease. We hypothesize that 6R-BH4 will improve vascular function in these patients.

Detailed description

Decreased production of nitric oxide (NO) from the endothelium (the layer of cells that forms the lining of all blood vessels) has been shown to contribute to atherosclerosis. NO has multiple beneficial effects on vascular function. Endothelial function can be measured in humans via a number of methods, and endothelial dysfunction has been shown to be a strong adverse predictor of cardiovascular events and mortality. Tetrahydrobiopterin (BH4) is essential for the production of NO in endothelial cells. 6R-BH4 is a synthetic version of naturally occurring BH4. We aim to investigate the effects of oral 6R-BH4 supplementation on endothelial function in patients with coronary artery disease.

Interventions

DRUG6R-BH4

6R-BH4 tablets 700mg/day, 6R-BH4 tablets 400mg/day or placebo

Study design

Allocation

RANDOMIZED

Intervention model

PARALLEL

Primary purpose

TREATMENT

Masking

DOUBLE (Subject, Investigator)

Eligibility

Sex/Gender

ALL

Age

18 Years to No maximum

Healthy volunteers

Inclusion criteria

* Multi-vessel coronary artery disease scheduled for coronary artery bypass surgery (CABG)

Exclusion criteria

* Inability to provide informed consent * Female subject who is pregnant, lactating or planning pregnancy during course of study * Prior clinical diagnosis of heart failure requiring diuretic therapy with evidence of severe left ventricular dysfunction * Recent acute coronary event (\<4 weeks) * Emergency CABG * Newly diagnosed diabetes mellitus (\<1 month) * Body weight \>130kg * Impaired renal function (creatinine \>180umol/l) * Elevated liver function tests (ALT \>50umol/l or AST \>2x normal) * Pacemakers, ICDs or metallic implants not compatible with MRI scanning * Subjects receiving experimental medications or participating in another study * Terminally ill subjects * Known hypersensitivity to 6R-BH4 * Concomitant treatment with methotrexate, levodopa, PDE-3 or PDE-5 inhibitors

Design outcomes

Primary

Measure	Time frame
Vascular function using non-invasive magnetic resonance imaging (MRI).	Pre- and post- treatment with 6R-BH4 or placebo

Secondary

Measure	Time frame
Laboratory measures of vascular function.	At time of CABG surgery

Countries

United Kingdom

Contacts

Primary ContactColin Cunnington, MBChB MRCP

colin.cunnington@cardiov.ox.ac.uk+44-1865-221866

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026