Biogen stock price target cut to $247 from $341 at

SVB Leerink analysts cut their price target on shares of Biogen Inc. to $247 from $341 on Friday. "The uncertainties about the outlook for their MS and SMA franchises are significant," wrote analysts led by Geoffrey Porges, who maintained their market perform rating on the stock. Porges said he and his team "assume that the company takes the responsible decision to terminate all further investments in beta amyloid-directed medicines (which has not occurred), and saves their investors the cash and saves patients and investigators from the burden of such studies. If Biogen does not make this decision, then our adjusted expense forecast could be too low, with further negative effects on our valuation even compared to our new PT." However, despite doubts about the efficacy of drugs based on the amyloid hypothesis, Biogen is forging ahead with its next amyloid-based trial; drug development partner Eisai Co. Ltd. announced on Friday the initiation of another Phase 3 trial, this time evaluating BAN2401, a monoclonal antibody that binds to neutralize and eliminate toxic beta amyloid aggregates. Biogen's stock, which fell 1.1% in premarket trade Friday, plunged 29% on Thursday after the company announced it was discontinuing trials for Alzheimer's drug aducanumab. Shares of the drugmaker have fallen 25% in the year to date, while the S&P 500 has gained 13.9%.

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