Biogen posts earnings of $4.50 a share vs $4.08 expected

Analysts had expected Biogen to report earnings of about $4.08 a share on $2.71 billion in revenue, according to a consensus estimate from Thomson Reuters. Earlier this month on CNBC's " Closing Bell," CEO George Scangos reflected on the impact of the hot button issue. —CNBC's Christine Wang contributed to this report..