Genzyme Corporation announced today that its Board of
Directors unanimously recommends that Genzyme shareholders accept the
sanofi-aventis revised tender offer to purchase all outstanding shares of
Genzyme common stock for $74.00 and one contingent value right, per share. The
Board recommends that all Genzyme shareholders tender their shares into the revised
tender offer.

Genzyme has filed with the Securities and Exchange
Commission an amendment to its Solicitation/Recommendation Statement on
Schedule 14D-9 that includes the basis for the Board’s recommendation along with
other information relating to the tender offer.