Medical experts divided on whether 2nd FDA-approved Alzheimer’s drug offers benefit

A hand holding a magnifying glass over an MRI of the brain of a patient with Alzheimer's disease.

An MRI of the brain of a patient with Alzheimer’s disease. (Getty Images)

The Food and Drug Administration recently approved a drug that could help patients in the early stages of Alzheimer’s disease by slowing disease progression. In clinical trials, the drug, called lecanemab, reduced the rate of cognitive decline in participants.

But doctors and health experts are split on whether it warranted expedited FDA approval. While some of them have welcomed the agency’s decision, describing the drug as groundbreaking, others are skeptical whether it offers substantial benefit.

In the United States, more than 6 million people live with Alzheimer’s disease, an incurable and fatal disease that affects the brain and leads to loss of cognitive function over time. Although there are medications available to treat the symptoms of Alzheimer’s disease, no treatment addresses the underlying cause of the disease. This is why some doctors have welcomed the accelerated approval of lecanemab. The FDA is likely to consider full approval later this year.

“We’re thrilled to finally have something,” Dr. Reisa Sperling, who directs the Alzheimer’s Disease Research and Treatment Center at Brigham and Women’s Hospital in Boston, told NPR recently.

Heather Snyder, vice president of medical and scientific relations for the Alzheimer’s Association, told Yahoo News that the organization is “celebrating” the drug’s approval on Jan. 6. “This is now the second approved treatment that evidence suggests significantly alters the course of Alzheimer’s disease,” she said.

Lecanemab, which will be marketed as Leqembi, is the second Alzheimer’s drug to receive accelerated approval from the FDA. This accelerated approval is usually granted to promising treatments targeting conditions for which there are no other effective options available. In the summer of 2021, the agency also gave accelerated approval to a similar drug – aducanumab, sold under the brand name Aduhelm. But the move was controversial because the FDA approved the drug despite conflicting evidence about whether it provided benefit to patients and against the recommendation of one of its outside expert committees.

Aduhelm’s expedited approval sparked a congressional investigation. Since then, the federal Medicare program has decided not to cover the Aduhelm treatment for the general population, but only for patients who were enrolled in the clinical trial. Some hospital systems across the country have also refused to offer the drug to patients with Alzheimer’s disease. Due to the controversy surrounding the drug’s effectiveness and its high price, as well as the negative publicity it received, few patients received it. As a result, many physicians treating the disease have found themselves, once again, with limited options.

Snyder said that while Leqembi isn’t a cure, the fact that it can slow disease progression would give patients more time to enjoy aspects of daily living.

“It could be things like going to a birthday party or going to a wedding, recognizing their spouse, their children, their grandchildren, their neighbors, and really that time allows an individual to also make decisions about their care as you go. too,” she said.

A single-dose vial of Leqembi with the drug packaging.

Lecanemab, which will be marketed as Leqembi, received accelerated approval from the FDA on January 6. (Eisai via Reuters)

Like Aduhelm, canemab was developed by Eisai in partnership with fellow drugmaker Biogen. These treatments are monoclonal antibody therapies designed to remove a substance called beta-amyloid from the brain. Beta-amyloid is a naturally occurring protein that becomes toxic when it clumps together and forms the sticky plaques that characterize Alzheimer’s disease.

The theory behind the development of monoclonal antibody treatments like lecanemab is that amyloid plaques cause brain cell loss that leads to cognitive decline in people with Alzheimer’s disease. By reducing the amount of amyloid plaques in the brain, these treatments are believed to help slow the process of memory loss and cognitive decline.

In a clinical study of nearly 1,800 people in the early stages of Alzheimer’s disease, those who received lecanemab for 18 months experienced 27% less impairment in memory and thinking compared to those who received lecanemab for 18 months. who received a placebo. Although the trial results were positive and unprecedented, some experts believe that the popularity of the drug is not commensurate with its apparent benefit.

“Clinical trial data show a statistically significant but clinically undetectable difference in outcome measure between active treatment and placebo over 18 months,” said Dr. Michael Greicius, professor of neurology and neurological sciences at the University of Stanford at Yahoo News.

He said the fast-track FDA approval of lecanemab made sense because, in clinical trials, the drug has shown it can affect a disease-associated biomarker. In this case, that biomarker is the reduction of beta-amyloid in the brain. “Lecanemab permanently clears amyloid plaques,” Greicius said.

But some experts worry that lecanemab’s approval could cause drug companies to focus on therapies that target amyloid plaques while neglecting other therapeutic approaches that might be more successful.

“I see it as a game-changer, but in a negative way, because it will change the clinical and research landscape around Alzheimer’s disease,” Greicius said.

The new drug, which is given by intravenous infusion every two weeks, is expensive. The companies developing it said it would cost $26,500 per year. So far, the Centers for Medicare and Medicaid Services (CMS) has said they won’t cover the drug, and unless lecanemab receives full FDA approval, that likely won’t change.

“What CMS is doing by limiting the coverage of approved treatments is unprecedented,” Snyder said. “It’s not something we’ve seen before, and it’s not.”

If CMS ultimately decides not to cover lecanemab, Greicius said, the drug will likely be used, but not very widely, as it will have to be paid for out of pocket.

He noted that there are safety issues regarding lecanemab that need to be considered, particularly a condition that can occur with most other drugs that remove amyloid plaques from the brain, known as ARIA. , or amyloid-related imaging abnormalities. Two forms of ARIA involve brain swelling and bleeding.

In the lecanemab study, more than 12% of people who received the drug had brain swelling and more than 17% had bleeding. While few participants experienced complications, there were at least three drug-related deaths, although these patients appeared to have had additional risk factors.

But Snyder said those side effects shouldn’t be a reason for doctors and patients in the early stages of the disease not to consider the drug.

“It’s really important to remember that Alzheimer’s is deadly…and all treatments have side effects,” she said. “So it’s important that we manage them and understand them, and a person should weigh any treatment decision – not just with this drug or this disease, but at all levels – to be able to weigh the benefits and the potential risks. [in] conversation with their clinician.

Leave a Comment