Encysive Pharmaceuticals

(ENCY)

, reeling from regulatory setbacks for its main drug, announced plans for a complete restructuring of its business.

The drug developer said Monday that it will replace its CEO, cut 70% of its workforce and end a key trial of its hypertension drug, Thelin.

Shares of Encysive

were crushed last week after the company's third attempt at satisfying U.S. regulatory concerns about Thelin as a treatment for pulmonary arterial hypertension fell short. The Food and Drug Administration said that Thelin "did not demonstrate the evidence of effectiveness needed for approval" and would require another clinical trial to supply that proof.

On Monday, Encysive said that George Cole will replace Bruce Given as president and chief executive. Cole previously had served as chief operating officer; that position has now been eliminated.

Encysive will cut its workforce by about 70% to 65 people. About 150 employees -- including the company's entire U.S. sales force -- will be laid off immediately. The remainder will leave in coming months.

Encysive expects to record about $15 million in restructuring-related costs in 2007. The company anticipates about $58 million in cash at the end of the second quarter.

Meanwhile, Encysive will discontinue its ongoing U.S. study of Thelin for PAH. Instead, the company plans to focus on the sales and marketing of Thelin in Europe, Canada and Australia, where the drug has been approved.

The company said it will continue plans for "advancing" Thelin as a PAH treatment in the U.S., along with oral Thelin as a treatment for diastolic heart failure.