The Food and Drug Administration鈥檚 decision next week whether to approve the first treatment for Alzheimer鈥檚 disease highlights a deep division over the drug鈥檚 benefits as well as criticism about the integrity of the FDA approval process.
The agency said it will decide by June 7 the fate of Biogen鈥檚 drug aducanumab, despite of the product by an of outside experts in November. Doubts were raised when, in 2019, Biogen halted two large clinical trials of the drug after determining it wouldn鈥檛 reach its targets for efficacy. But the drugmaker later , stating that one trial showed the drug reduced the decline in patients鈥 cognitive and functional ability by 22%.
Some FDA scientists in November to present a document praising the intravenous drug. But other FDA officials and many outside experts say the and that another large clinical trial is needed. A consumer advocacy group has called for a federal investigation into the FDA鈥檚 handling of the approval process for the product.
A lot is riding on the drug for Biogen. It is projected to carry a $50,000-a-year price tag and would be worth billions of dollars in revenue to the Cambridge, Massachusetts, company.
The FDA is under pressure because an estimated 6 million Americans are diagnosed with Alzheimer鈥檚, a debilitating and ultimately fatal form of dementia, and there are no drugs on the market to treat the underlying disease. Although some drugs slightly mitigate symptoms, patients and their families are desperate for a medication that even modestly slows its progression.
Aducanumab helps the body produce antibodies that remove amyloid plaques from the brain, which has been associated with Alzheimer鈥檚. It鈥檚 designed for patients with mild-to-moderate cognitive decline from Alzheimer鈥檚, of which there are an estimated 2 million Americans. But it鈥檚 not clear whether eliminating the plaque improves brain function in Alzheimer鈥檚 patients. So far, nearly two dozen drugs based on the so-called amyloid hypothesis have failed in clinical trials.
Besides questions about whether the drug works, there also are safety issues in experienced brain swelling and nearly 20% had brain bleeding, though those symptoms generally were mild and controllable. Because of those risks, patients receiving aducanumab have to undergo regular brain monitoring through expensive PET scans and MRI tests.
Some physicians who treat Alzheimer鈥檚 patients say even if it鈥檚 approved.
鈥淭here鈥檚 a lot of hope among my patients that this is going to be a game changer,鈥 said Dr. Matthew Schrag, an assistant professor of neurology at Vanderbilt University. 鈥淏ut the cognitive benefits of this drug are quite small, we don鈥檛 know the long-term safety risks, and there will be a lot of practical issues in deploying this therapy. We have to wait until we鈥檙e certain we鈥檙e doing the right thing for patients.鈥
Many aspects of aducanumab鈥檚 journey through the FDA approval process have been unusual. It鈥檚 鈥渧anishingly rare鈥 for a drug to continue on toward approval after its clinical trial was halted because unfavorable results showed that further testing was futile, said Dr. Peter Lurie, president of the Center for Science in the Public Interest and a former FDA associate commissioner. And it鈥檚 鈥渕ind-boggling,鈥 he added, for the FDA to collaborate with a drugmaker in presenting to an FDA advisory committee.
鈥淎 joint briefing document strikes me as completely inappropriate and an abdication of the FDA鈥檚 claim to being the best regulatory agency in the world,鈥 Lurie said.
Three FDA advisory committee members who voted in November against approving the drug wrote in a that the FDA鈥檚 鈥渦nusual degree of collaboration鈥 with Biogen led to criticism that it 鈥減otentially compromised the FDA鈥檚 objectivity.鈥 They cast doubt on both the drug鈥檚 safety and the revised efficacy data.
The FDA and Biogen declined to comment for this article.
Despite the uncertainties, the Alzheimer鈥檚 Association, the nation鈥檚 largest Alzheimer鈥檚 patient advocacy group, has pushed hard for FDA approval of aducanumab, mounting last month. The 鈥淢ore Time鈥 campaign featured personal stories from patients and family members. In one ad, actor Samuel L. Jackson posted on Twitter, 鈥淚f a drug could slow Alzheimer鈥檚, giving me more time with my mom, I would have read to her more.鈥
But the association has for having its representatives testify before the FDA in support of the drug without disclosing that it received $ last year from Biogen and its partner company, Eisai, and hundreds of thousands of dollars more in previous years. Other people who testified stated upfront whether or not they had financial conflicts.
Dr. Leslie Norins, founder of a group called Alzheimer鈥檚 Germ Quest that supports research, said the lack of disclosure hurts the Alzheimer鈥檚 Association鈥檚 credibility. 鈥淲hen the association asks the FDA to approve a drug, shouldn鈥檛 it have to reveal that it received millions of dollars from the drug company?鈥 he asked.
But Joanne Pike, the Alzheimer鈥檚 Association鈥檚 chief strategy officer, who testified before the FDA advisory committee about aducanumab without disclosing the contributions, denied that the association was hiding anything or that it supported the drug鈥檚 approval because of the drugmakers鈥 money. Anyone can search the to find all corporate contributions, she said in an interview.
Pike said her association backs the drug鈥檚 approval because its potential to slow patients鈥 cognitive and functional decline offers substantial benefits to patients and their caregivers, its side effects are 鈥渕anageable,鈥 and it will spur the development of other, more effective Alzheimer鈥檚 treatments.
鈥淗istory has shown that approvals of first drugs in a category benefit people because they invigorate the pipeline,鈥 she said. 鈥淭he first drug is a start, and the second and third and fourth treatment could do even better.鈥
Lurie disputed that. He said lowering the FDA鈥檚 standards and approving an ineffective or marginally effective drug merely encourages other manufacturers to develop similar, 鈥渕e too鈥 drugs that also don鈥檛 work well.

The Public Citizen Health Research Group, which opposes approval of aducanumab, has called for an investigation of the FDA鈥檚 鈥渦nprecedented and inappropriate close collaboration鈥 with Biogen. It asked the inspector general of the Department of Health and Human Services to probe the approval process, which that office said it would consider.
The group also urged the acting FDA commissioner, Dr. Janet Woodcock, to remove Dr. Billy Dunn, an aducanumab advocate who testified about it to the advisory committee, from his position as director of the FDA鈥檚 Office of Neuroscience and hand over review of the drug to staffers who weren鈥檛 involved in the Biogen collaboration.
Woodcock refused, saying in a letter that FDA 鈥渋nteractions鈥 with drugmakers make drug development 鈥渕ore efficient and more effective鈥 and 鈥渄o not interfere with the FDA鈥檚 independent perspective.鈥
Although it would be unusual for the FDA to approve a drug after rejection by an FDA advisory committee, it鈥檚 not unprecedented, Lurie said. Alternatively, the agency could approve it on a restricted basis, limiting it to a segment of the Alzheimer鈥檚 patient population and/or requiring Biogen to monitor patients.
鈥淭hat will be tempting but shouldn鈥檛 be the way the problem is solved,鈥 he said. 鈥淚f the product doesn鈥檛 work, it doesn鈥檛 work. Once it鈥檚 on the market, it鈥檚 very difficult to get it off.鈥
If the drug is approved, Alzheimer鈥檚 patients and their families will have to make a difficult calculation, balancing the limited potential benefits with proven safety issues.
Anne Saint, whose husband, Mike, had Alzheimer鈥檚 for a decade and died in September at age 71, said that based on what she鈥檚 read about aducanumab, she wouldn鈥檛 have put him on the drug.
鈥淢ike was having brain bleeds anyway, and I wouldn鈥檛 have risked him having any more side effects, with no sure positive outcome,鈥 said Saint, who lives in Franklin, Tennessee. 鈥淚t sounds like maybe that drug鈥檚 not going to work, for a lot of money.鈥
Their adult daughter, Sarah Riley Saint, feels differently. 鈥淚f this is the only hope, why not try it and see if it helps?鈥 she said.
