The Company board member has unanimously decided to drop the $18.5 billion all-cash proposal made by French drugmaker Sanofi-Aventis, Genzyme Corp. announced on Monday.

The decision has been backed with claims that the offer would undervalue the Company.

Genzyme has revealed that the offer letter publically unveiled on Sunday by Sanofi's Chief Executive, Chris Viehbacher, contained a proposal to takeover Genzyme for $69 a share, which is exactly similar to the offer it made the preceding month. Besides, it contained no new information.

"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", Mr. Termeer posted.

Moreover, Sanofi and its advisers have shown their extreme keenness in acquiring the Company and are even ready to pay more, Genzyme outlined. However, the Company is not prepared for the offer.

Shares of Genzyme were recorded to mark a climb 3.9% touching $70.25 in premarket trading, and the same is more compared to the share price offered.

Sanofi's continuous attempts to acquire offer Genzyme signifies that the French Pharma is desperate to mark its footprints in the entrepreneurial culture, novel science along with concentrating on biotechnology sector.