The acting director of the Food and Drug Administration is asking for a federal investigation into the agency's approval of Biogen's (BIIB) - Get Biogen Inc. Report Alzheimer's disease treatment, Aduhelm.
Shares of the Cambridge, Mass., drugmaker at last check were down 3% to $358.33.
Biogen did not immediately respond to a request for comment.
Acting Commissioner Janet Woodcock asked in a letter to the Office of the Inspector General to investigate how agency staff interacted with Biogen prior to the drug's approval in June.
Woodcock wrote to acting Inspector General Christi Grimm that concerns were continuing to be raised "regarding contacts between representatives from Biogen and FDA during the review process, including some that may have occurred outside of the formal correspondence process."
"To the extent these concerns could undermine the public’s confidence in FDA’s decision," Woodcock wrote, "I believe it is critical that the events at issue be reviewed by an independent body such as the Office of Inspector General in order to determine whether any interactions that occurred between Biogen and FDA review staff were inconsistent with FDA policies and procedures.”
Biogen partners on the drug with Japan's Eisai ESALY.
The news comes one day after the FDA approved changes to the product information for Aduhelm.
The label now says the drug has not been studied in treating later stages of the disease and should be given to patients with "mild cognitive impairment or mild dementia stage of disease."
In November, scientific advisers to the FDA recommended rejection of the drug.
The FDA's Peripheral and Central Nervous System Drugs Advisory Committee voted 8 to 1 against recommending approval of Biogen's treatment aducanumab, while two members cast "undecided" votes.
The agency isn’t bound to follow its advisers’ advice, but it generally follows the recommendations of its underlying advisory panels.