S-A in informal talks to acquire Genzyme

French drugmaker sanofi-aventis (S-A) has approached Genzyme regarding a potential acquisition, according to a "reliable" source.

It is thought that S-A started informal talks with Genzyme, the largest maker of medicines for genetic diseases, about two weeks ago. The talks remain at an early stage and issues such as price and management have yet to be discussed.

Acquiring Genzyme would help S-A expand in biotechnology. Earlier this month, sources suggested S-A was planning an acquisition in the US that may be worth $20bn or more, but declined to be specific.

At the time, analysts cited Genzyme as a potential target for a takeover as well as Allegan and Biogen Idec.

Genzyme's current market capitalisation is close to $14bn.

Shares in the biotech firm climbed 21 per cent on the news of the talks, marking the largest stock price increase for Genzyme in more than a decade.