Biogen’s share price soared 40 percent as the FDA approved its drug for Alzheimer’s disease

Biogen’s shares surged more than 40 percent after U.S. Food and Drug Administration staff said there was enough data to support approval of the company’s experimental Alzheimer’s drug. “The applicant has provided a large amount of validity evidence to support the approval,” FDA staff said in a document posted on the agency’s website reviewing the drug.

Biogen's share price soared 40 percent as the FDA approved its drug for Alzheimer's disease

Biogen’s drug, Aducanumab, targets a “sticky” compound in the brain called amyloid protein, which is assumed to play a role in the devastating disease. A panel of outside experts is expected to meet Friday to recommend FDA approval for the drug.

Currently, the FDA has not approved a drug that reverses the mental decline caused by Alzheimer’s disease, the sixth leading cause of death in the United States.

FDA-approved Alzheimer’s drugs are designed to relieve symptoms, not actually reverse or slow down the disease itself.

Biogen estimates that about 1.5 million early-stage Alzheimer’s patients in the United States may be candidates for the drug.

The FDA’s final decision on Biogen’s drug is expected in March.