A $44 billion biotech just got some good news from the FDA about a key Alzheimer's drug, and the stock is soaring

• Biogen and Eisai said their experimental Alzheimer's drug will be reviewed more quickly by regulators at the US Food and Drug Administration.
• If the drug is approved, it would be the first treatment to reduce the clinical decline of Alzheimer's disease.
• The companies abandoned the drug in 2019, saying it didn't work, only to revive it months later.
• In response to this news, shares of Biogen were up about 9%.

The biotech giant Biogen just said US regulators will give its potential Alzheimer's treatment a speedy review, sending the company's stock soaring.

The US Food and Drug Administration will rule on the company's treatment, called aducanumab, by March 7, Biogen and its research partner Eisai said in a statement. After the announcement, Biogen's shares climbed about 9%, giving the company a market value of $44 billion.

The FDA also said it will hold an advisory committee meeting to review the drug, but didn't provide a date, according to the companies.

Biogen CEO Michel Vounatsos called the news "an important step in the path to potentially having a treatment that meaningfully changes the course of Alzheimer's disease," in a statement.

If this application goes well, this would be the first Alzheimer's drug to reduce the cognitive decline of the illness. The drug works by targeting the protein amyloid beta in the brain.

The company abandoned further development of the drug after disappointing trials in 2019, then resumed work on it later that year.