SILVER SPRING, Md. (AP) -- United Therapeutics Corp. said Monday that federal regulators have again rejected its application for an extended-release, tablet version of its pulmonary arterial hypertension drug treprostinil.
Shares of the Silver Spring, Md., company dropped 2 percent, or $1.31, to $49.64 Monday after the announcement, while broader trading indexes fell slightly.
United Therapeutics plans to request a meeting with the Food and Drug Administration to discuss the agency's response.
In initially rejecting the drug in October, the FDA questioned the importance of trials that measured six-minute walk distance for patients and the inability of the trials to demonstrate effectiveness in improving that measurement or lengthening the time until the condition got worse.
Pulmonary arterial hypertension is a potentially fatal condition in which patients have abnormally high blood pressure in the arteries of the lungs.
United Therapeutics sells an injectable version of treprostinil under the brand name Remodulin and an inhalable version under the brand Tyvaso.
The company had resubmitted its application for the tablet version of the drug after the FDA rejected it last fall.
United Therapeutics shares had climbed 14 percent so far in 2013, as of Friday, after closing 2012 at $53.42. The shares slipped below $50 after United Therapeutics announced the first FDA rejection in October.