BOSTON (CBS) – After nine months of denials, rejection, bickering and finally, discussion, French pharmaceutical company Sanofi-Aventis of Paris has signed a deal to buy Genzyme of Cambridge for $20.1 billion plus other milestone payments in the future.

Sanofi already has a presence in the Boston area with a new oncology research center, another facility on Albany Street, and a lab of Memorial Drive. Sanofi-Aventis CEO Chris Vienbacher says the company now wants to “leverage Genzyme’s presence and connections in what is clearly a hotbed of scientific activity” in Massachusetts.

Genzyme shareholders will get $74.00 per share in cash and one “Contingent Value Right” for each share which allows for additional cash payments of $14.00 if certain milestones are met.

Analysts seem to agree that the deal is beneficial to both companies but some layoffs could be expected locally as the companies merge some operations.

Listen to WBZ NewsRadio 1030′s Anthony Silva’s extended report on the acquisition and reaction: