continued falling Friday, a day after the company said U.S. regulators wouldn't act until mid-June on its treatment for a rare blood-pressure disorder.
Although Encysive and Wall Street had hoped for a shorter review, the Houston-based biotechnology company says the Food and Drug Administration will take another six months to analyze its application for Thelin.
By early afternoon, shares were down 30 cents, or 6.7%, to $4.19 on trading that was more than triple the average volume for the past three months. On Thursday, after Encysive announced the FDA's decision, the stock plunged by 24%.
Encysive has secured European Union approval for Thelin, but the company has experienced a series of delays and setbacks at the FDA for the treatment for pulmonary arterial hypertension.
PAH, which can lead to heart failure, causes high pressure in the artery that carries blood from the heart to the small arteries in the lungs. PAH affects about 50,000 Americans and 200,000 people worldwide.
Several drugs are already available, including market-leader Tracleer from
and Revatio, a
drug that contains the same ingredient found in the impotence pill Viagra.
Other companies are working on new PAH drugs, most notably
. At one point, Gilead's ambrisentan was well behind Thelin in the regulatory race to the FDA. But Gilead has closed the gap, filing its application in mid-December.