ENCYSIVE SUBMITS RESPONSE TO THELIN APPROVABLE LETTER

Encysive Pharmaceuticals announced that, following discussions with the FDA, the company has submitted a complete response to the approvable letter issued by the FDA in July regarding the company's new drug application for Thelin (sitaxsentan sodium) 100-mg tablets. The FDA is evaluating Thelin as a potential oral treatment for pulmonary arterial hypertension.

The company expects to hear within approximately 30 days whether the FDA accepts the submission, and, if so, the FDA will establish a new action date under the Prescription Drug User Fee Act.

The company had received an FDA approvable letter for Thelin requesting additional clinical trial work in March. After responding, Encysive received another approvable letter in July, which addressed an issue not resolved in the company's response and again offered the alternative of conducting additional trials. Additionally, the FDA provided recommendations on the company's risk management plan.

The European Commission approved 100-mg Thelin tablets in August. The approval allows Encysive to market the drug in all 25 member states of the European Union.