Making sense of the latest Alzheimer’s research

An estimated 6.9 million U.S. adults age 65 and older are living with Alzheimer's disease. This number is projected to double by 2060, according to an April 2024 article published in Alzheimer's Dementia. What could disrupt this worrisome trend: a medical breakthrough to prevent or cure the disease. But despite decades of investigation, scientists are still working to understand all the factors that may contribute to the development of Alzheimer's and how to manage them. New approaches that stop the progression of the disease (not just temporarily slow it down) are needed and there are millions of people looking for such glimmers of hope on the horizon. But for many, repeated headlines about potential breakthroughs in Alzheimer's treatment may seem more confusing than promising.

In July 2024, the U.S. Food and Drug Administration approved Kisunla (donanemab-azbt) injection for the treatment of Alzheimer’s. The drug was approved under the FDA’s Fast Track, Priority Review, and Breakthrough Therapy designations for people with early-stage Alzheimer’s or mild cognitive impairment or dementia. In a clinical trial involving 1,736 patients (more than half were women, they ranged in age from 59 to 86, and 90 percent where white), participants were randomized assigned to receive the therapy or placebo. They study showed those who got the drug had a significant reduction in mental decline compared to those who didn’t. The drug is not a cure, but it could help slow progression of Alzheimer’s when it’s taken early on, potentially giving those with the disease something that is both precious and elusive: more time.

Earlier in January 2023, the FDA also approved lecanemab. At the time, the drug was hailed as a game changer, possibly one of the first to potentially slow the progression of cognitive decline. But like Kisunla, lecanemab is not a cure for Alzheimer's and the risks aren’t zero.

"Science is slow. Progress is built on small, incremental steps," explains Upinder Singh, MD, a doctor specializing in geriatrics at Southern Hills Hospital and Kindred Healthcare in Las Vegas, Nevada. "But researchers, doctors, and the media are all enthusiastic. Because of that enthusiasm, tiny steps are often called ‘major leaps’ or ‘breakthroughs.’ But be careful: don’t let the hype and hope outweigh reality.”

Read past the headlines

When Alzheimer’s studies make the front page, it’s okay to share in the scientists’ excitement. But read the story carefully so you can decide for yourself whether it’s worth all the media buzz. Keep these hard-hitting questions in mind:

How advanced is the research?

Before a drug or a treatment can become available to the public, it must go through a series of studies to make sure it’s safe and effective for humans. An article may feature a drug that’s in the preclinical phase, which means it’s still being tested on cells or animals. If the animals don’t show any major side effects, it may be approved for clinical trials in humans.

There are four trial phases, each one involving more people than the one before it.

Phase one involves a small number of volunteers to test the safety of a drug at various doses. Phases two and three focus more on the drug’s effectiveness. If the drug is shown to be safe and effective in phases one through three, the FDA may approve it. After it becomes available on the market, researchers continue to track its safety among thousands of people over long periods of time (phase four).

“In each phase, the benefits have to significantly outweigh the risks for something to be called ‘medicine,’” says Dr. Singh. “Many drugs don’t make it because they show positive results in one phase, but don’t pan out later.”

Alzheimer’s drugs have an especially hard time reaching the market because even if a drug improves someone’s brain scans or brain chemistry, it won’t necessarily improve their symptoms or change the course of their disease.

Did the study look at what the headline’s claiming?

Make sure that the grabby headline matches the study’s findings.

Did the researchers focus on a single Alzheimer’s symptom, but the headline claims there’s a cure?

Did the drug improve patients’ brain scans, but didn’t have a real impact on their memory?

“It’s important to ask if the study has any effect on what you’re trying to treat,” says Singh. “There may be a medicine that removes the tangles and plaques—proteins that build up in the brain to cause Alzheimer’s—and that’s very good. But if the drug doesn’t help you think or improve your symptoms, then it’s no use for you.”

How Alzheimer’s research might work for you

If you read about a clinical trial that you’d like to sign up for—or that sounds like a good match for a friend or loved one—it’s good to start by finding out which company is funding it. Then ask your healthcare provider (HCP) for more information about the company and the trial and whether you might be eligible to participate. You can use the Alzheimer’s Association TrialMatch tool to compare trials and choose the best fit. You can also find out about trials through the National Institute of Aging’s clinical trials search tool.

With smart research and guidance from your HCP, you or a loved one may be able to take advantage of the exciting advances being made in Alzheimer’s science.