Encysive Pharmaceuticals Shares Fall After FDA Asks For More Clinical Trial Data For Thelin Approval

HOUSTON, March 24 /PRNewswire-FirstCall/ -- Encysive Pharmaceuticals today announced that the Company has received an approvable letter from the U.S. Food and Drug Administration (FDA) for Thelin(TM) (sitaxsentan sodium), which is under review for the treatment of pulmonary arterial hypertension (PAH). The action letter contains concerns and observations that must be satisfied prior to achieving approval, including a request for additional clinical trial work.

"We will work in close collaboration with the FDA to clarify the path forward. We are hopeful that this can be accomplished without the need for additional clinical work, but that will require discussion with the Agency before we can be sure," said Bruce D. Given, M.D., President and Chief Executive Officer of Encysive Pharmaceuticals. "We remain confident in Thelin's value, and look forward to the opportunity to provide PAH patients with a new treatment option."

Conference Call Information

Encysive will host a conference call on Monday, March 27, at 7:00 a.m. ET. You may access the call either through the call-in number below or through the audio webcast. The access number for the call is:

Number: (612) 332-1210

Passcode: Encysive Pharmaceuticals

This call is being webcast and can be accessed via Encysive's web site at http://www.encysive.com . A replay of the webcast will be available on the Company's web site through April 27, 2006. Additionally, a replay of the call will be available until March 31, 2006 at 11:59 p.m. ET. The call replay can be accessed by calling:

Number: (320) 365-3844 Access Code: 824081 About Encysive Pharmaceuticals

Encysive Pharmaceuticals Inc. is a biopharmaceutical company engaged in the discovery, development and commercialization of novel, synthetic, small molecule compounds to address unmet medical needs. Our research and development programs are predominantly focused on the treatment and prevention of interrelated diseases of the vascular endothelium and exploit our expertise in the area of the intravascular inflammatory process, referred to as the inflammatory cascade, and vascular diseases. To learn more about Encysive Pharmaceuticals please visit our web site: http://www.encysive.com .

This news release contains forward-looking statements that involve risks and uncertainties, including statements with respect to: prospects for regulatory approval of Thelin by the FDA and other statements regarding matters that are not historical facts. You may identify some of these forward-looking statements by the use of words in the statements such as "anticipate," "estimate," "expect," "project," "intend," "plan," "believe" or other words and terms of similar meaning. Among the factors that could cause actual results to differ materially from those indicated by such forward- looking statements are: unexpected delays in regulatory approval of Thelin; the availability of sufficient funds to continue research and development efforts and the commercialization of Thelin as well as more specific risks and uncertainties facing Encysive such as those set forth in its reports on Form 8-K, 10-Q and 10-K filed with the U.S. Securities and Exchange Commission. Given these risks and uncertainties, any or all of these forward-looking statements may prove to be incorrect. Therefore, you should not rely on any such factors or forward- looking statements. Furthermore, Encysive does not intend to update publicly any forward-looking statement, except as required by law. The Private Securities Litigation Reform Act of 1995 permits this discussion.

Encysive Pharmaceuticals Inc.

CONTACT: investors, Ann Tanabe, VP, Investor Relations and CorporateCommunications of Encysive Pharmaceuticals Inc., +1-713-796-8822; or MarcyStrickler of The Trout Group, +1-212-477-9007, ext. 27; or media, DanBudwick of BMC Communications, +1-212-477-9007, ext. 14, both for EncysivePharmaceuticals Inc.

Back to news