Biogen faces FDA probe of Alzheimer’s drug approval

The head of the U.S. Food and Drug Administration said she is seeking a federal investigation of the approval of the Biogen Inc. Alzheimer’s disease drug Aduhelm, a highly unusual step that will increase scrutiny of a heavily criticized clearance.

In a letter posted on Twitter, Janet Woodcock, the agency’s acting commissioner, said she was requesting an independent review of whether any interactions between Biogen and FDA staff were inconsistent with the agency's policies and procedures. The inspector general for the Department of Health and Human Services would undertake the probe.

Aduhelm was granted approval by the FDA last month over the objection of outside scientific advisers who had voted against the drug last November. The agency ordered Biogen to do an additional trial to confirm that the drug benefits patients, and given nine years to produce data.

Biogen has priced the therapy at $56,000 annually.

In the letter, Woodcock said she had “tremendous confidence in the integrity” of the FDA staff, but said there were concerns over contacts between the agency and Biogen that may have occurred outside the normal formal correspondence process.

“It is critical that the events at issue be reviewed by an independent body,” she wrote.

A Biogen spokeswoman said that the company would cooperate with any inquiry into the Aduhelm review process.

Big trials of the drug that were halted by Biogen in 2019 produced contradictory results as to whether it slows cognitive decline. So the agency instead approved the drug under a special pathway that requires less data called accelerated approval. This possibility wasn’t considered by the outside advisers who reviewed the drug’s data in November 2020.

Throughout 2019, after Biogen had said it had stopped its trials because the drug was unlikely to work, FDA officials held regular meetings with company executives, according to a person familiar with the matter.