Biogen Stock (BIIB) After-Hours on Dec. 19, 2025: Why Shares Jumped, Where They Closed After the Bell, and What to Watch Before the Next Market Open
Biogen shares closed up 2.88% at $174.80 Friday, with trading volume surging to about 15 million shares, far above the 50-day average. The move followed bullish analyst commentary from RBC Capital, which reiterated an “Outperform” rating and a $210 price target. After-hours, BIIB edged higher to $176.23. Renewed focus on Alzheimer’s treatments and pipeline prospects drove activity.