Shares closed at $189.28 on Thursday as the S&P 500 rose 1.02% and the Dow gained 1.62% in a broadly positive US market session.
The decline ended a two-day winning streak, while Johnson & Johnson, Pfizer and AbbVie all advanced, with AbbVie posting the strongest gain at 3.64%.
Biogen finished 6.49% below its 52-week high of $202.41 reached on 6 February, and trading volume of 1.5 million topped its 50-day average of 1.1 million.
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