HOUSTON, Sept. 5, 2007 (PRIME NEWSWIRE) -- Encysive Pharmaceuticals Inc. (Nasdaq:ENCY) today announced that it has received a written response from the U.S. Food and Drug Administration (FDA) regarding Encysive's request for formal dispute resolution on its New Drug Application (NDA) for Thelin(tm) (sitaxsentan sodium) for the treatment of pulmonary arterial hypertension (PAH). The FDA's reviewer agreed with the decision of the Division of Cardiovascular and Renal Products that, while the data provided in the NDA are suggestive of the effectiveness of Thelin, it did not provide the substantial evidence of effectiveness needed for approval. The reviewer encouraged the Company to conduct an additional study to demonstrate the drug's effectiveness in exercise capacity as measured by change in six-minute walk distance.
