Troubled Genzyme Corp says billionaire investor Carl Icahn has notified the firm of his intention to nominate four people to the board of directors, including himself.

Genzyme said it will evaluate the nominees and make a recommendation that is “in the best interests of all of the company’s shareholders”. The board presently consists of nine directors, all of whom are up for election at the annual meeting scheduled for May 20.

Chief executive Henri Termeer seemed pretty positive about the news, saying that “our actions demonstrate that we are open and responsive to shareholder input, and we welcome a constructive dialogue with Mr Icahn”. The latter upped his stake in Genzyme to 4.8 million from 1.5 million shares during the fourth quarter.

Mr Icahn’s move comes a couple of months after another shareholder, Relational Investors (which owns 4%), requested representation on Genzyme’s board but then agreed to defer that request and “support the board’s nominees and proposals in 2010”. In return for the backing, Genzyme agreed to appoint Ralph Whitworth, co-founder of the institutional investor, to the board if representation is requested in November 2010.

Genzyme has had a tough time since June 2009 when its Allston Landing, Boston facility was temporarily shut down, affecting production of Cerezyme (imiglucerase) for Gaucher disease and Fabrazyme (agalsidase beta) for Fabry disease. Then, in November, the US Food and Drug Administration warned of the potential for foreign particle contamination in all lots of the two aforementioned therapies plus Myozyme (alglucosidase alpha) for Pompe disease, Aldurazyme (laronidase) for mucopolysaccharidosis type I and Thyrogen (thyrotropin alpha) for thyroid cancer.

However Mr Termeer believes that “Genzyme is regaining its momentum and will return to delivering sustainable growth this year”. He added that “we have made significant changes to strengthen the company by investing in existing businesses, bringing in new senior leadership and improving corporate governance”.

Mr Icahn’s bid for representation on the board comes at a time when he is trying to get more directors on the board at fellow US biotech major Biogen Idec. What plans he may have for Genzyme are not clear but observers believe getting an Icahn slate of directors in could signal an end to the company’s growth-by-acquisition strategy pursued by Mr Termeer who has been at the helm since 1985.