The purpose of this study is to determine whether the addition of sapropterin dihydrochloride
(6R-BH4) to existing treatment has any effect in patients with pulmonary arterial
hypertension (PAH). Patients with PAH have low levels of a substance called nitric oxide
(NO). Tetrahydrobiopterin (BH4) is a substance produced by the body that is an essential
requirement in the formation of NO. NO is thought to be helpful in keeping blood vessels in
the lung healthy. 6R-BH4 is an experimental (unproven) medicine made in the lab that is very
much like the BH4 that our own body makes. The researchers are investigating whether 6R-BH4
can be added safely to current treatment for PAH and whether there is any evidence of benefit
from its use. The study will take approximately one year to complete from the time
recruitment begins.
The primary objective of the study is to evaluate the safety of oral 6R-BH4, administered in
escalating doses in addition to standard care, in subjects with pulmonary arterial
hypertension (PAH).
The secondary objective of the study is to evaluate change in biochemical markers of
endothelial dysfunction and nitric oxide synthetase activity (coupled and uncoupled) in
subjects with PAH receiving escalating doses of oral 6R-BH4 in addition to standard care.
The third objective of the study is to evaluate change in biomarkers of disease progression,
6-minute walk (6MW) distance, Borg dyspnea scores, and quality of life (QOL) measures in
subjects with PAH receiving escalating doses of oral 6R-BH4 in addition to standard care.
Phase:
Phase 1
Details
Lead Sponsor:
Vanderbilt University Vanderbilt University Medical Center
Collaborators:
BioMarin Pharmaceutical National Institutes of Health (NIH)