An Open-Label Extension Trial of UT-15C SR in Subjects with Pulmonary Arterial Hypertension

Combination treatment of PAH with therapies targeting different mechanisms of
action has great promise in addressing the multiple pathophysiologic mechanisms
that are implicated in PAH. These combinations may produce an additive effect
or enhance and prolong the effect of other therapeutic agents.
Remodulin (treprostinil sodium) is an effective agent given by subcutaneous or
intravenous delivery. UT-15C is a diethanolamine salt of treprostinil and is
being investigated as a solid-dose oral compound. An oral product is easier to
use.

To provide, or continue to provide, UT-15C SR for eligible subjects who
participated in protocols TDE-PH-301 or TDE-PH-302 or TDE-PH-308 or additional
UC-15C SR clinical protocols.
To assess the long-term safety of UT-15C SR in these subjects through
assessment of adverse events and laboratory parameters.
To assess the effect of continued therapy with UT-15C SR on exercise capacity
after one year of treatment.

This is a multi-center, open-label study for eligible patients who participated
in Protocol TDE-PH-301, TDE-PH-302 or TDE-PH-308.

For subjects on placebo at the end of the TDE-PH-301, TDE-PH-302 and TDE-PH-308
protocols, treatment will be initiated at 0,25 mg twice daily (every 12 hours
+/- 1 hour) with dose escalation of an additional 0,25 mg or 0,5 mg twice daily
every 3 days. The 0,125 mg strength, if available, may be used thoughout the
study if a 0,25 mg dose increase is not tolerated and an intermediate dose is
required.
For subjects on active therapy in TDE-PH-301, TDE-PH-302 or TDE-PH-308 the
initial dose of the open-label study will be based upon their ending dose in
the main pivotal studies.

Study visits will be timed to occur 3, 6, 12, 24, and 36 months after each
subject*s first exposure to UT-15C SR and yearly visits beyond 36 months.
Subjects receiving placebo in the previous study myst be contacted weekly by
telephone during the first 12 weeks of the open label study. Monthly telephone
calls must be conducted of all subjects actively participating in the
TDE-PH-304. In addition to the study visits, all subjects must be seen in the
clinic no less than once every six months for routine standard of care.

For subjects who were randomized to placebo in the previous study, the subject
should remain close to the study site for approximately 3 to 6 hours for
periodic observation and monitoring of possible AEs.

The most commonly observed side effects of UT-15C SR reported during previous
studies included headache, nausea, diarrhea, facial flushing, jaw pain and pain
in extremity.

The risks associated with the 6-Minute Walk Test may include the possibility of
fatigue, fainting, muscle soreness, strain or injury.