Shares of Biogen gained 1.4% in premarket trading on Thursday after the drug maker beat earnings expectations and even though it saw revenue drop 25% for the quarter. Biogen had earnings of $410.2 million, or $2.69 per share, in the first quarter of 2021, compared to $1.4 billion, or $8.10 per share, in the like quarter in 2020. Adjusted earnings per share were $5.34, against a FactSet consensus of $4.97. Biogen’s revenue fell roughly 25% to $2.69 billion for the quarter, down from $3.53 billion in the first quarter of last year. The FactSet consensus was $2.65 billion. Its top-selling drug is multiple-sclerosis therapy Tecfidera, which generated $479.3 million in revenue for the quarter, down from $1.1 billion in the same quarter last year. The company said its guidance for the year assumes “rapid erosion of Tecfidera in the U.S.” in 2021. It also raised its outlook for adjusted EPS to $17.50 to $19.00, from $17.00 to $18.50. Biogen said it expects that aducanumab, its somewhat controversial Alzheimer’s disease drug candidate, will get approved by U.S. regulators by June 7. Biogen’s stock is up 10.2% for the year, while the S&P 500 has gained 10.1%.

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