A Phase III, International, Multi-Center, Randomized, Double-Blind, Placebo-Controlled, Event Driven Study to Compare the Time to First Clinical Worsening in Subjects with Pulmonary Arterial Hypertension Receiving UT-15C in Combination with a PDE5-I or ERA Compared with a PDE5-I or ERA Alone

Principal Investigator

Akram Khan

Study Purpose

Pulmonary artery hypertension (PAH) is a medical disorder in which pressure in the blood vessels going from the right side of the heart to the lungs is higher than normal. The increased blood pressure in the lungs places a strain on the heart. This strain causes the heart to pump less blood into the lungs, causing physical symptoms of swelling in the feet and abdomen. These symptoms can get worse over time due to the decreased pumping ability of the heart. The purpose of this study is to evaluate the safety and effectiveness of treprostinil diethanolamine (UT-15C SR), the study drug, in treating subjects with pulmonary arterial hypertension (PAH). This study drug is a tablet that is taken by mouth and is released over an extended period of time (sustained release or SR). The study drug will be compared to placebo (pill that looks like the study drug but has no medication in it). The purpose of this study will look at how effective and safe the study drug is in treating PAH in subjects who are also taking a PDE-5 or an ERA.

Medical Condition(s)

Pulmonary artery hypertension.

Eligibility Criteria

Subjects with pulmonary arterial hypertension (PAH) who are using conventional treatments for their PAH (e.g. anticoagulants, diuretics, oxygen use or digoxin) AND either a PDE-5 (phosphodiesterase-5 inhibitors) or a ERA (endothelin receptor antagonist) are eligible to participate in the study.
Inclusion Criteria:
Between 18 and 75 years of age, inclusive
PAH that is idiopathic / heritable, PAH associated with connective tissue disease, HIV infection, repaired congenital systemic-to-pulmonary shunts (repaired > 1 year), or appetite suppressant / toxin use
Receiving a PDE-5 inhibitor or ERA at an appropriate dose
Previous testing (e.g. right heart catheterization, echocardiography) consistent with diagnosis of PAH

Exclusion Criteria:
Nursing or pregnant
PAH due to conditions other than noted in the above inclusion criteria
History of uncontrolled sleep apnea, severe liver disease, left sided heart disease, uncontrolled systemic hypertension
Use of an investigational drug within 30 days of Baseline

Age Range

18 - 75

Healthy Volunteers Needed


Duration of Participation

Subjects will be asked to come to the clinic up to 4 times over a 24-week period once the screening/baseline visit is completed.

Minors Included



Akram Khan, M.D.
Pulmonary Critical Care & Sleep Medicine
Oregon Health and Science University
Multnomah Pavilion, 2nd floor, Room# 2514
3181 SW Sam Jackson Park Road
Mail Code UHN67
Portland, Oregon 97239-3098
Phone: 503-494-9570


United Therapeutics

Recruitment End


Compensation Provided


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