United Therapeutics Corporation announced that enrollment in its FREEDOM-C(2) registration trial was completed on March 18, 2011.

FREEDOM-C(2) is a 16-week, multi-center, international, double-blind, randomized, placebo-controlled study of a sustained release oral formulation of treprostinil diethanolamine (UT-15C) in pulmonary arterial hypertension (PAH) patients receiving an endothelin receptor antagonist and/or a phosphodiesterase-5 inhibitor.

The FREEDOM-C(2) study randomized 313 patients, compared to a target enrollment of 300 patients.  The primary endpoint of the trial is change in six-minute walk distance at Week 16 in the treatment group compared to placebo.

"Completion of enrollment in FREEDOM-C(2) represents another significant milestone toward the planned filing of the UT-15C NDA," said Roger Jeffs, Ph.D., president and chief operating officer of United Therapeutics. "This study, if successful, will support the use of UT-15C as add-on therapy to currently approved oral medications, and should significantly enhance early adoption and market uptake of UT-15C."

United Therapeutics expects to unblind and announce preliminary analysis of the FREEDOM-C(2) study results in September 2011.

United Therapeutics is a biotechnology company focused on the development and commercialization of unique products to address the unmet medical needs of patients with chronic and life-threatening conditions.