Sanofi Extends Offer for Genzyme

France's Sanofi-Aventis says it will extend its cash buyout offer for Genzyme until next month, as part of its agreed $20.1 billion takeover of the U.S.-based specialty drugmaker.

The French pharmaceutical giant says in a statement Monday that the $74-a-share offer will now close April 1.

It had been scheduled to end March 16.

Sanofi, the world's fourth-largest drugmaker, overcame Cambridge, Massachusetts-based Genzyme's reluctance to a takeover last month by raising its previous offer and agreeing to make additional cash payments pending the success of several drugs.

The deal was struck after nearly nine months of back and forth, with Sanofi-Aventis finally deciding Genzyme's portfolio of rare disease treatments was worth adding an extra $5 a share to its original offer.