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Roche offers $3b for medical test maker

SAN FRANCISCO -- Roche Holding AG, the world's biggest maker of diagnostic tests, offered to buy Ventana Medical Systems Inc. for about $3 billion as it expands screening to match patients with the right drugs.

The $75-a-share bid is 45 percent higher than Ventana's closing price of $51.74 yesterday . The offer is "an important step" in Roche's move into personalized medicine, or finding treatments based on genetic analysis, the company said yesterday in a statement distributed by PR Newswire.

One of Ventana's new tests, for breast cancer, is used to tell which patients might respond to treatment from Genentech Inc.'s Herceptin, which had $1.2 billion in sales in 2006. Roche is Genentech's majority owner. Ventana has fended off repeated attempts to negotiate a takeover, Roche said.

"The board will consider the offer in due course," Ventana chief financial officer Lawrence Mehren said in a telephone interview. He declined to comment further.

The stock surged above the offering price to $78.61 in extended trading, suggesting investors expect a higher offer.

"We believe we are the best strategic partner to capitalize on Ventana's potential," said Roche's chief executive, Franz Humer, in the statement.

Shares of Ventana slipped 21 cents to $51.74 in Nasdaq trading. They have gained 20 percent this year. Roche's shares fell 0.2 Swiss francs to 211.9 Swiss francs.

Roche, based in Basel, Switzerland, said it would retain Ventana's management team and employees, as well as its Tucson, Ariz., headquarters.

In a letter made public yesterday , Humer said he proposed in February that Roche set up a partnership with Ventana similar to its "longstanding successful relationship with Genentech." Roche would have acquired a majority of the company's shares at a premium, and the company would have continued to be publicly traded, Humer wrote. The proposal was rebuffed, Humer wrote.

Ventana's tests analyze human tissues to diagnose cancer and infectious diseases, the company said. Ventana also makes scientific instruments and chemical supplies for pharmaceutical and biotech companies.

Ventana had sales of $64.4 million in the first quarter, up 19 percent from the same period a year earlier. Net income was $18 million. In April, Ventana said it expects 2007 revenue of $285 million to $289 million.