The Associated Press

TRENTON, N.J. — French drugmaker Sanofi-Aventis SA (NYSE: SNY) is sticking to its original offer of $69 a share to buy U.S. biotech company Genzyme Corp. (Nasdaq: GENZ), a Sanofi spokesman said Thursday.

That’s despite rumors Paris-based Sanofi has upped its offer by $2 a share, two months after its first overture to Genzyme. The Cambridge, Mass., company has rejected as too low the $69 cash offer, which would make the deal worth $18.5 billion.

With media in Europe today reporting a higher offer of $71 per share, a Sanofi spokesman in the U.S. on Thursday said the company hasn’t changed the price it proposed two months ago.

“We have one offer on the table and that’s the public offer we made two months ago,” said spokesman Jack Cox.

Cox confirmed that Sanofi CEO Chris Viehbacher has been meeting privately with Genzyme shareholders in the U.S. this week to promote the offer. Viehbacher, a former executive with GlaxoSmithKline, has many connections with the Research Triangle Park, N.C. area.

“Due to the great interest in Sanofi-Aventis’s offer, Mr. Viehbacher has decided to set aside some time to meet with a selection of Genzyme shareholders to discuss the proposal while in the country for other previously scheduled meetings,” Cox said.

He could not provide any details on which or how many Genzyme shareholders Viehbacher has been meeting with here.

Viehbacher frequently takes business trips to the U.S., where Sanofi, the maker of blockbuster anti-clotting drug Plavix, has multiple offices and manufacturing facilities. Its U.S. headquarters is in Bridgewater, N.J.

Sanofi-Aventis has said it sent Genzyme’s management a detailed purchase proposal on July 29, but it was flatly rejected on Aug. 11. Financial advisers of the two companies have met, but top officials of Genzyme have refused to hold talks with counterparts at Sanofi.

On Aug. 30, the day after Sanofi finally went public with its offer, Genzyme’s chief executive, Henri A. Termeer, wrote to Viehbacher that with the offer still at $69 a share, there was no reason for talks involving Genzyme’s board.

“The Genzyme board is not prepared to engage in merger negotiations with Sanofi based upon an opportunistic proposal with an unrealistic starting price that dramatically undervalues our company,” Termeer wrote in the letter, which was released publicly.

He apparently was referring to manufacturing problems that Genzyme has been struggling with for months. The company has reduced production of its two key drugs for genetic diseases, Cerezyme and Fabrazyme, although Genzyme says the situation is improving.

Genzyme spokesman Bo Piela said the company had no comment Thursday.

Sanofi is the world’s fourth-biggest pharmaceutical company, with 2009 revenue of about $35.5 billion. Its top seller is the Lantus insulin brand for diabetes, and it jointly markets with Bristol-Myers Squibb Co. the blood thinner Plavix, the world’s No. 2 drug with about $9 billion in sales last year. Cheaper rivals to Plavix will hit the market in 2012.

Like other big drugmakers, Sanofi has been buying up small companies or rights to promising experimental drugs to overcome inadequate progress from internal research programs and increased competition from generic products.

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