Biogen stock heads before the bell after Japan approval

At the close on September 15, 2026, Biogen stock finished at USD 216.17 on Nasdaq and fell 0.55 percent. The shares traded 4.4 percent below their 52-week high, while Biogen and Eisai said LEQEMBI Pen was approved in Japan on September 16, 2026.

Biogen stock finished at USD 216.17 on Nasdaq on September 15, 2026, down 0.55 percent. Biogen Inc. (ISIN US09062X1037, Nasdaq: BIIB) traded in a 52-week band from USD 135.39 to USD 225.80, and the close sat about 4.4 percent below the high.

September 15, 2026 in numbers

Per CNBC, Biogen's regular-session volume was 708,173 shares and the after-hours indication was USD 216.17 on September 15, 2026. The same page showed a 52-week range of USD 135.39 to USD 225.80, leaving the shares near the top of that band. On the same session, the S and P 500 fell 0.4 percent to 7,551.81, according to WTOP.

Today after the Japan approval

On September 16, 2026, GlobeNewswire said Eisai and Biogen announced Japan approval for LEQEMBI Pen, a subcutaneous formulation of lecanemab. The release said the approval marked the third country globally to authorize the SC formulation. The stock heads into today with that regulatory update in focus.