United Therapeutics, Lung Rx submit NDA for inhalational threpostinil
United Therapeutics and its wholly owned subsidiary, Lung Rx, have submitted a new drug application (NDA) to the FDA for marketing approval of an inhaled formulation of treprostinil for the treatment of pulmonary arterial hypertension (PAH).

The submission starts a 60-day period, during which the FDA will examine the application for completeness. If the FDA accepts the inhaled formulation of treprostinil (ITRE) NDA for review, then it is expected to be subject to the standard 10- to 12-month review period before an action letter is issued, according to the Silver Spring, Md.-based company.

United and LungRx said that its ITRE NDA is principally supported by data from the TRIUMPH-1 (TReprostinil Sodium Inhalation Used in the Management of Pulmonary Arterial Hypertension) phase III clinical trial, a randomized, double-blind, placebo-controlled trial of patients with PAH.

According to United and LungRx, the study population consisted of 235 patients who were optimized on an approved oral therapy for PAH, either bosentan (Tracleer), an endothelin receptor antagonist, or sildenafil (Revatio), a phosphodiesterase-5 inhibitor. The majority of patients were New York Heart Association Class III (~98 percent) of varied etiologies, including idiopathic or familial PAH (~60 percent), collagen vascular disease associated PAH (~30 percent), and PAH associated with HIV, anorexigens or other associated conditions (~10 percent), according to the companies.