En español | Treatment for Alzheimer's disease, the devastating condition that affects more than 5 million Americans, has remained notoriously elusive for decades. Now, a small study released by drug company Eli Lilly offers at least a flicker of hope: It shows that the experimental drug donanemab may significantly slow patients’ cognitive decline.
The two-year study — which followed 272 people whose brain scans showed Alzheimer's — found that patients who took the drug had a 32 percent slower rate of decline than those who received a placebo. “It's very encouraging because this is the first time a drug of its kind has had positive results in early-stage trials,” says Lon Schneider, M.D., Della Martin chair in psychiatry and neuroscience at the Keck School of Medicine of the University of Southern California. The drug, known as a monoclonal antibody, works by binding to the hard plaque in the brain made from amyloid (a protein associated with Alzheimer's).
Though these initial findings are promising, Schneider says more data is needed. “It may have been everyone just had a small cognitive decline, in which case the results aren't as significant,” he says. (The drugmaker has said it will release this information shortly in a peer-reviewed clinical journal.)
But this isn't the only news Alzheimer's researchers are excited about. “There are several new drugs either close to getting FDA approval, or in development, that promise to really change the playing field when it comes to treatment of Alzheimer's disease,” says Marwan Sabbagh, M.D., director of the Cleveland Clinic Lou Ruvo Center for Brain Health in Las Vegas. Here are some of the most promising contenders.
Aducanumab: This drug, up for FDA approval, is another monoclonal antibody similar to donanemab that binds to the hard amyloid plaques that are the hallmarks of Alzheimer's disease. “It will be a game changer if it's approved, because this will be the first drug shown to actually slow down the progression of Alzheimer's disease,” Sabbagh says. (Editor’s Note: Aducanumab, brand name Aduhelm, received FDA approval on June 7, 2021.)
Pimavanserin: This antipsychotic drug, already approved to treat hallucinations and delusions in people with Parkinson's disease, is under FDA review for the treatment of some of the behavioral and psychological symptoms of all dementias. “Research shows that it's very effective also in treating dementia-related psychosis or hallucinations,” Sabbagh says. “This is important because these sorts of episodes are the main reason patients with Alzheimer's get placed in memory care facilities. If caregivers can manage these symptoms, more people will be able to stay at home.”
Atuzaginstat: There's a growing body of evidence that the bacteria P. gingivalis (the cause of gum disease) can infect the brain and cause Alzheimer's disease. Atuzaginstat is in clinical trials to see if it can inactivate gingipains, the toxic proteins the bacteria release, which can damage healthy brain cells.
NDX-1017: This drug — administered as a daily injectable — is a small molecule that improves the activity of hepatocyte growth factor (HGF), a protein found in your body's tissues, including your brain. It's thought that HGF can strengthen the synapses or connections between your brain cells, thus reversing some of the damage caused by Alzheimer's disease. Brain wave studies in patients show that the drug works quickly, causing changes in as little as eight days.
ALZ-801: This medication offers an advantage over other drugs in clinical research, because you can take it orally rather than as an injection. Unlike monoclonal antibodies, which grab onto amyloid plaques and eliminate them, this drug attacks earlier in the process, blocking the amyloid from ever forming. Right now, studies are only in people with a high genetic risk of Alzheimer's who carry two copies of the APOE4 gene. But if this research proves successful, the drug will be tried on other groups in the early stages of Alzheimer's, Sabbagh says.
Lenalidomide (Revlimid): Used to treat blood cancers such as leukemia or multiple myeloma, this medication is now being studied at the Cleveland Clinic for its potential to treat Alzheimer's. “Our early research has shown that it will inhibit amyloid plaques in the brains of mice,” Sabbagh says.