Encysive Pharmaceuticals Receives FDA Response on Thelin

Encysive Pharmaceuticals reported that it has received a written response from the FDA regarding the company’s request for formal dispute resolution on its new drug application for Thelin, a treatment of pulmonary arterial hypertension.

The FDA’s reviewer agreed with the decision of the Division of Cardiovascular and Renal Products that, while the data provided in the application are suggestive of the effectiveness of Thelin (sitaxsentan sodium), 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.

George Cole, Encysive’s president and CEO, said that the company’s clinical team is developing an additional Phase III study protocol in case a new trial is required for FDA approval.