The first new Alzheimer’s drug in nearly two decades was approved by the U.S. Food and Drug Administration on Monday, despite opposition from the agency’s own independent advisory committee and some experts who said there wasn’t enough proof the drug could actually help patients.
In clinical trials, aducanumab (Aduhelm) showed a 22% reduction in the development of thinking and memory problems associated with Alzheimer’s disease, according to a statement from the Alzheimer’s Association. The patient advocacy group had urged the FDA to approve the drug, hailing it as a treatment “that could make a meaningful difference in the lives of individuals living with Alzheimer’s and their families.”
However, Monday’s approval flies in the face of a near-unanimous recommendation against use of the drug by the FDA’s own independent advisory committee, as well the objections of a number of prominent Alzheimer’s experts.
Recognizing that clinical trials of the drug offered incomplete and conflicting evidence of its effectiveness, the FDA says it has granted approval on the condition that drug maker Biogen conduct a new clinical trial.
“The need for treatments is urgent: right now, more than 6 million Americans are living with Alzheimer’s disease and this number is expected to grow as the population ages,” the FDA said in a statement. “Although the Aduhelm data are complicated with respect to its clinical benefits, [the] FDA has determined that there is substantial evidence that Aduhelm reduces amyloid beta plaques in the brain and that the reduction in these plaques is reasonably likely to predict important benefits to patients.”
The “FDA will continue to monitor Aduhelm as it reaches the market and ultimately the patient’s bedside. Additionally, FDA is requiring Biogen to conduct a post-approval clinical trial to verify the drug’s clinical benefit,” the agency said. “If the drug does not work as intended, we can take steps to remove it from the market.
Back in November, 10 of 11 members on an FDA advisory panel voted against approval, even after hearing a presentation by the agency’s director of neuroscience arguing there is “strong” evidence supporting the drug.
Three advisory committee members went even further, writing a detailed critique of the evidence. They have been joined by a host of other scientists, including even those who participated in aducanumab’s clinical trials, The New York Times reported.
“I simply don’t see a path for approval because of the absence of evidence that’s been shared to date that this product works, and I think it would set a remarkably dangerous precedent — not only for the field of Alzheimer’s research but also for the broader regulation of prescription drugs in our country,” Dr. G. Caleb Alexander, an FDA advisory committee member with the Johns Hopkins Bloomberg School of Public Health in Baltimore, told the Times.
Still, the drug is being hailed by advocates like the Alzheimer’s Association as the first medication to directly target a potential cause of the progressive neurological disease, rather than just its symptoms. It is the first new Alzheimer’s drug approved by the FDA since 2003.
“This will give us a new biological foothold to build on,” Stephen Salloway, director of neurology and the Memory and Aging Program at Butler Hospital in Providence, R.I., told the Washington Post. “To get the best in class, you have to have the first in class.”
The intravenous drug would be a moneymaker for Biogen, and could cost as much as $50,000-a-year per patient, the Post reported.
The drug’s development path has been rocky. In March 2019, Biogen announced it was halting two clinical trials of aducanumab because the drug didn’t seem to be making enough of a difference.
But Biogen reversed its decision seven months later, after more analysis of data from one of the trials found aducanumab showed some positive effect at higher doses, the Times reported.
Dr. David Knopman, a neurologist at the Mayo Clinic and a principal investigator for one of the trials, told the Times, “One study was positive, and one identically performed study was negative. I don’t think it takes a PhD in statistics to see that that’s inconclusive.”
Experts also noted that the drug poses potential safety risks for some patients. About two of five patients taking the high dose of aducanumab experienced brain swelling or bleeding, the Times said, but the effects were mild enough that they caused only 6% of participants to drop out of the trial.
Advocacy groups urging approval noted the need for some new treatment, even if its effectiveness hasn’t been conclusively proven.
“With more than 6 million Americans living with Alzheimer’s, the need for a treatment for a disease that has no survivors has never been greater,” the Alzheimer’s Association said in its statement.
The Alzheimer’s Association has more about FDA-approved treatments for Alzheimer’s symptoms.
SOURCES: June 2, 2021, statements, Alzheimer’s Association; U.S. Food & Drug Administration; The New York Times; Washington Post