Updated from 12:59 p.m. EDT

Gilead Sciences ( GILD) is acquiring CV Therapeutics ( CVTX) in a $1.4 billion cash deal that will boost Gilead's nascent cardiovascular drug franchise, the companies announced Thursday.

The acquisition values CV Therapeutics at $20 a share, or a 25% premium to the stock's closing price Wednesday. Gilead is swooping in with a higher offer for CV Therapeutics after Japanese drug maker Astellas sought to buy the company for $16 a share, an offer that was rebuffed multiple times by CV Therapeutics' board of directors.

Gilead is best known for its market-leading HIV drug franchise, but the company has recently branched out with drugs to treat pulmonary and cardiovascular disease. CV Therapeutics owns Ranexa, a drug to treat chronic angina, and Lexiscan, a cardiac stress agent.

Gilead is developing a new drug, darusentan, for persistent hypertension. Data from two phase III studies of darusentan are expected later this year.

"The acquisition of CV Therapeutics represents a unique opportunity to complement and strengthen our growing cardiovascular portfolio," said Gilead chairman and CEO John Martin.

Gilead says the acquisition of CV Therapeutics will be dilutive to earnings in 2009 and neutral to accretive in 2010.

Gilead shares were gaining 0.9% to $43.43 in recent trading.

Te Gilead-CV merger follows a slew of drug-firm deals in recent weeks, including Roche's purchase of Genentech ( DNA) -- also announced Thursday -- Merck's ( MRK) $41 billion merger with Schering-Plough ( SGP), and Pfizer's ( PFE) $68 billion acquisition of Wyeth ( WYE)

At the time of publication, Feuerstein's Biotech Select model portfolio was long Gilead Sciences, CV Therapeutics and Genentech.

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