As Biogen stock soared 38% Monday on the surprise Food and Drug Administration approval of its hotly debated treatment for Alzheimer’s disease, investors bid up the shares of would-be competitors large and small.
Eli Lilly was the biggest beneficiary, rising nearly 12% and adding more than $20 billion in market capitalization. Like Biogen’s drug, called Aduhelm, Lilly’s most advanced Alzheimer’s treatment targets toxic brain plaques called beta amyloid. AC Immune, a Swiss biotech company with a once-failed amyloid treatment of its own, rose about 26%. Prothena, which has an amyloid-targeting drug in early-stage development, went up 27%.