The head of the FDA is calling for an investigation into her agency's controversial decision to approve a new Alzheimer's drug

• Interim FDA Commissioner Janet Woodcock has asked for an outside investigation into an Alzheimer's drug approval.
• The agency approved the drug, Aduhelm, last month, despite a lack of evidence showing the drug slowed the disease.
• Officials from Biogen and the FDA worked closely together to revive the drug, raising concerns.
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The top leader at the US Food and Drug Administration is asking for an investigation into the agency's controversial decision to approve an expensive new Alzheimer's disease treatment.

Janet Woodcock, acting commissioner of the FDA, published a letter Friday asking the federal government's top inspector to investigate if FDA staff worked inappropriately with biotech company Biogen to approve the new drug.

"To the extent these concerns could undermine the public's confidence in FDA's decision, I believe that it is critical that the events at issue be reviewed by an independent body such as the Office of the Inspector General, in order to determine whether any interactions that occurred between Biogen and FDA review staff were inconsistent with FDA policies and procedures," she wrote in the open letter.

The drug in question, Aduhelm, was approved by the agency last month and has caused an uproar in the scientific community. Three of the agency's scientific advisors resigned following the decision.

Documents released by the FDA last month show that people within the agency thought that the drug should not have been approved because human testing data didn't show it worked, but their concerns were overridden by top staff.

Biogen officials used back channels to get the drug approved after a late-stage clinical trial failed in March 2019, according to a report from STAT News.

The interactions pre-dated Woodcock, who became interim commissioner in January when the Biden Administration took office. She has been with the FDA for more than two decades and is one of the top contenders to permanently take the role, according to biotech analysts.

After the FDA approved Aduhelm, Biogen set its price at about $56,000 a year. Analysts estimate the US Medicare program could pay anywhere from $6 billion to $29 billion per year for Aduhelm, according to a recent New York Times analysis.

Biogen's stock, which surged when the FDA approved Aduhelm, declined 3.2% to $357.09 a share on Friday afternoon.