A Phase 2, Pharmacokinetic (PK) Study of 6R-BH4 Alone or 6R-BH4 With Vitamin C in Subjects With Endothelial Dysfunction

Exclusion Criteria

• •Hypertension secondary to other medical conditions (e.g., renal failure or steroid usage).
• •Concurrent disease or condition that would interfere with study participation or safety, such as bleeding disorders; history of syncope or vertigo; severe gastroesophageal reflux disease (GERD); heart failure; symptomatic coronary disease; arrhythmia; serious neurologic disorders, including seizures; organ transplant; or organ failure.
• •Type 2 diabetics that are uncontrolled, unstable, newly diagnosed, or have changed therapy in the last three months and all Type 1 diabetics.
• •Any severe comorbid condition that would limit life expectancy to \< 6 months.
• •Serum creatinine \> 2.0 mg/dL, or hepatic enzyme concentrations \> 2 times the upper limit of normal
• •HIV infection, hepatic cirrhosis, other preexisting liver disease, or positive HIV, Hepatitis B or C test at screening.
• •Concomitant treatment with:
• •* Drugs known to inhibit folate metabolism (e.g., methotrexate)
• •* Levodopa
• •* A phosphodiesterase (PDE) 5 inhibitor (e.g., Viagra®, Cialis®, Levitra®, or Revatio®)
• •* A PDE 3 inhibitor (e.g., cilostazol, milrinone, or vesnarinone)
• •Use of any investigational product or investigational medical device within 30 days prior to screening, or requirement for any investigational agent prior to completion of all scheduled study assessments.
• •Myocardial infarction, stroke, or surgery within the last 60 days prior to screening.
• •History of alcohol and/or drug abuse or a positive alcohol or drug test at screening.
• •Previous treatment with any formulation of BH4.
• •Has known hypersensitivity to 6R-BH4 or its excipients.
• •Pregnant or breastfeeding at screening, or planning to become pregnant (self or partner) at any time during the study.
• •Any condition that, in the view of the PI, places the subject at high risk of poor treatment compliance or of not completing the study.