In spite of various clinical trials, the list of FDA-approved medications for Alzheimer’s has hardly changed since my father died in 2005. Three of their approved drugs are cholinesterase inhibitors, and the Alzheimer’s Association notes that people taking such drugs “performed better on memory and thinking tests than those taking a placebo.” They add, however, that “the degree of improvement was small.” My father took one of those drugs for a time—Aricept—but to no clear effect.
The latest drug to win FDA approval is aducanumab, which will be sold by Biogen under the trade name Aduhelm. It’s likely to be prescribed for early- and mid-stage Alzheimer’s patients, and will be administered monthly, by infusion. Clinical trials have shown that it lowers the amount of amyloid plaque in the brain, but its ability to slow cognitive decline is still in question. One Biogen trial showed aducanumab to be mildly effective, but a second trial yielded no benefits over the placebo.
The Alzheimer’s Association has welcomed the drug, which is understandable, given the long wait for a medication that will alleviate one of the country’s major health care problems. Critics of aducanumab point out that the FDA ignored the findings of its own panel of independent advisors, which recommended, in the fall of 2020, that the drug should not be approved. They also note the potential side effects. Some 40% of the patients in the original trials suffered from painful brain swelling, and about 17% from small cerebral hemorrhages. To monitor these problems, patients will take MRI brain scans twice a year.
Trials are underway for several other Alzheimer’s drugs, but there’s nothing in sight that would cure the disease. We hope at best to slow it down—and even this can be wildly expensive. Biogen has set Aduhelm’s price at $56,000 a year. Medicare may cover 80% of this charge, but if it does, and many patients sign up, the cost could swamp Medicare’s budget. Nevertheless, as the first drug approved for Alzheimer’s in eighteen years, it’s a ray of hope for some.
(NB: The FDA has recently changed its advice on Aduhelm, and now recommends it only for early, not mid-stage Alzheimer's patients.)