SAN DIEGO – A company that claims to have the first drug to slow mental decline from Alzheimer's disease made its case to scientists Thursday but left them sharply divided over whether there's enough evidence of effectiveness for the medicine to warrant federal approval.
Excitement and skepticism have surrounded aducanumab since its developers stopped two studies this year because it didn't seem to be working, then did a stunning about-face in October and said new results suggest it was effective at a high dose.
During Thursday's presentation at an Alzheimer's conference in San Diego, the developers convinced some experts that the drug deserves serious consideration. But others were dubious. Changes made during the study and unusual analyses of the data made the results hard to interpret. And the newly released results showed the drug made only a small difference in thinking skills in one study and none in the other.
Alzheimer's patients and families are desperate for any help, no matter how small, adding pressure on the Food and Drug Administration to approve something. But with conflicting results, “I don't see how you can conclude anything other than that another trial needs to be done,” said the Mayo Clinic's Dr. David Knopman, who was involved in one of the studies.
Laurie Ryan, a dementia scientist at the National Institute on Aging, agreed: “We need more evidence.”
Other doctors who consult for the drug's developers cheered the results. Dr. Paul Aisen, a dementia specialist at the University of Southern California, said they were “consistent and positive” in showing a benefit at a high dose – “a truly major advance.”
Aducanumab aims to help the body clear harmful plaques, or protein clumps, from the brain. Cambridge, Massachusetts-based Biogen is developing it with Japan's Eisai.