American biotech firm Biogen Inc. recorded its biggest daily gain in seven months after its Alzheimer’s disease therapy scored regulatory approval in the United States, Yahoo!finance reported.

Biogen Inc
  • Biogen shares climbed by as much as 64% after its therapy was approved by the U.S. FDA which triggered a trading halt. The stock closed up 38% at $395.85 to post its biggest daily gain since the treatment was found effective in November.
  • The Alzheimer’s disease therapy aducanumab will be sold under the brand Aduhelm. It will cost $56,000 a year according to a joint statement of Biogen and its Japanese partner Eisai Co. Ltd.
  • Shares of Eisai traded in the United States jumped 56% to close $116.03 apiece. In Tokyo, shares climbed by the daily limit of 19%. Year-to-date gains are at 25%.

The partners sought for aducanumab approval in Japan  last December but it could take a year for a decision to be made. BIIB is down 0.046% premarket.