Congressional Investigation into Alzheimer’s Drug Aduhelm Faults the F.D.A. and Biogen

The F.D.A.’s own internal inquiry said there was “no evidence” its interactions with Biogen were “anything but appropriate,” given the data’s complexity and the importance of Alzheimer’s, but it issued four recommendations to prevent future problems. The congressional report said that more than a year later, the F.D.A. still had not fully implemented them.

The congressional report also questioned the F.D.A.’s decision to give the drug a special designation, known as “accelerated approval.” The agency had “abruptly changed course,” the report noted, after months of saying Aduhelm would only be considered for traditional approval.

The report, confirming previous reporting by The Times, said the change came after a council of senior agency officials met to review Aduhelm, also called aducanumab, and resoundingly agreed there wasn’t enough evidence that it worked. According to minutes of the meeting obtained by The Times, the council said another clinical trial should be conducted first, and one member warned that otherwise, approval could “result in millions of patients taking aducanumab without any indication of receiving any benefit, or worse, cause harm.”

But just three weeks after that meeting, in April 2021, the F.D.A. told Biogen it was now considering Aduhelm for “accelerated approval,” which allows authorization of drugs with uncertain benefit if they can treat serious diseases with few other options and if their biological mechanism is considered reasonably likely to help patients. Accelerated approval requires companies to conduct another trial, but the report noted that the F.D.A. gave Biogen more than eight years to complete it, allowing Aduhelm to be given to patients during that time.

The agency’s justification for accelerated approval was that Aduhelm targets a protein, amyloid, that forms plaques in the brains of Alzheimer’s patients. But many Alzheimer’s experts said years of data had not shown that reducing amyloid slowed cognitive decline.

The congressional report said it was a “notable lapse” that the agency did not reconvene an independent advisory committee or an internal group of experts to consider accelerated approval. It also said the agency contradicted its own guidance for Alzheimer’s drugs, which said “the standard for accelerated approval” had not yet been met for the disease. In its statement on Thursday, the F.D.A. said it “plans to update” the guidance, issued in 2018, “with the goal of continuing to further our drug review processes.”

The report also delved into the F.D.A.’s initial decision to approve Aduhelm for all Alzheimer’s patients even though it had only been tested on people in mild early stages of the disease. F.D.A. officials, justifying the decision, told the committees the broad label would have benefits, including allowing patients to continue on Aduhelm after their early disease worsened.