Pfizer has entered into an agreement to acquire Encysive Pharmaceuticals, Inc., a publicly held biopharma company, for an equity value of approximately $195 million.

Pfizer will acquire the rights to Thelin, an oral, endothelin A receptor antagonist (ETRA) for the treatment of pulmonary arterial hypertension (PAH), as well as Encysive’s other pipeline candidates. Thelin is approved for marketing in the EU and is currently available in the UK, Germany, Ireland, Spain, France, Italy, Belgium, Luxembourg and the Netherlands. The drug has also been approved in Australia and Canada. In the U.S., it has been the subject of three approvable letters from the FDA; Pfizer plans to conduct a Phase III trial to support registration in the U.S.

“The process initiated in July of 2007 to review Encysive’s strategic alternatives led us to consider a range of opportunities for increasing shareholder value,” commented George W. Cole, president and chief executive officer of Encysive. “After a thorough analysis, Encysive’s board of directors concluded that this cash transaction with Pfizer represents the best option for our shareholders now. Pfizer has come with a superior offer and with an in-depth understanding of pulmonary arterial hypertension, our primary therapeutic focus.”

“The acquisition of Encysive will add growing, near-term revenue from the European market and increase our already strong presence in the cardio-respiratory arena with a product that complements Revatio, a PAH treatment that was discovered and developed by Pfizer researchers,” said Ian Read, president of Pfizer’s Worldwide Pharmaceutical Operations. “We look forward to applying Pfizer’s significant resources to the launch of Thelin in additional countries.”

The transaction is expected to close in 2Q08, subject to customary closing conditions.