Having sparked off a frenzy of excitement in October about a possible sale, Biogen Idec now says that it plans to remain independent as no serious offers were made.

The biotechnology firm says that it conducted “a comprehensive and thorough sale process” with financial advisors Goldman Sachs and Merrill Lynch but at the conclusion of said process, “Biogen Idec did not receive any definitive offers to purchase the company”.

The restating of its independence is unlikely to please investors and the announcement, which came after the markets had closed, saw Biogen stock plunge over 27% in after-hours trading. The firm’s share price had been on the rise for some time as some of the biggest ‘big pharma’ firms were thought to be interested in buying, notably Pfizer, GlaxoSmithKline, Sanofi-Aventis and Novartis.

It now appears that the valuation put on Biogen, around the $25 billion mark, has put off even the major players. Even billionaire investor Carl Icahn, who bought a small stake in the company in August and had reportedly bid $23 billion for the firm, did not make a concrete offer.

The board at Biogen did not seem too upset, however. It said that the firm’s “business strategy is working and generating strong operating and financial performance,” adding that “continued execution” of that business plan “will result in attractive value for stockholders”.

The firm said it was confident of achieving “a series of goals” by year-end 2010. This involves having 100,000 patients on its multiple sclerosis treatment Tysabri (natalizumab) and more than 40% of the company's revenue coming from its international business. Biogen is also hoping that four new products and/or existing drugs will be launched in new indications by 2010.