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Dec 13 (Reuters) - Jefferies and Co cut Biogen Idec Inc's (BIIB.O) price target to $52 from $73 and said it was backing out its assigned acquisition premium, and reverting back to its previous valuation, following the company's announcement that it planned to remain independent after receving no takeover bids.
On Wednesday, the biotechnology firm ended its own auction after failing to get any bidders. Biogen, which has been wrestling with slowing growth for its flagship multiple sclerosis drug, Avonex, put itself up for sale in October.
Shares of the company were down more than 28 percent at $54, after closing at $75.88 Wednesday on the Nasdaq.
"With no bidders emerging, BIIB will again trade on its own fundamentals, which we find unimpressive," the brokerage said in a research note.
Biogen also reiterated its financial outlook for 2007. It said it aimed to increase earnings per share from 2007 through 2010 at a 25 percent compound annual growth rate.
"We believe management's long-term guidance is overly aggressive and unlikely to be achieved," Jefferies said. (Reporting by Sreerupa Mitra in Bangalore; Editing by Amitha Rajan)