Encysive Pharmaceuticals Inc. said Friday it responded to a Food and Drug Administration request to reformat data in its marketing application for the hypertension drug Thelin.

Shares of Encysive rose 36 cents, or 6.5 percent, to $5.89 in premarket activity, after shedding about 7 percent on Thursday when the company announced it had to reformat the data. Shares have traded between $3.29 and $10 in the last 52 weeks.

The FDA began asking for more data back in July, when many had expected the drug to be approved. Shares dropped about 40 percent in one day to close at $3.69, when Thelin's approval was delayed.

In November, the company responded to FDA's July request.

Thelin is designed to treat pulmonary arterial hypertension, or chronic high blood pressure in the blood vessel that carries oxygen-poor blood to the lungs. The condition causes shortness of breath, decreased activity, and eventually death unless treated with a transplant of the heart, lungs, or both.