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  • An experimental drug made by Eli Lilly appears to be effective in helping slow cognitive decline in people with Alzheimer’s disease.
  • The drug called donanemab was used in a Phase 3 trial with over 1,100 individuals participating. Officials at Eli Lilly said the drug was able to help people with mild cognitive impairment due to Alzheimer’s disease.
  • Eli Lilly officials said they will be asking the FDA for approval for the drug as an Alzheimer’s disease treatment this year.

We may soon have a new drug that can effectively slow cognitive decline in people with Alzheimer’s disease.

Eli Lilly and Company announced Wednesday that its experimental drug, called donanemab, proved both safe and efficacious in its phase 3 clinical trial.

Based on the positive results, Lilly will move forward with the global regulatory submissions process in hopes of bringing donanemab to market as soon as possible.

The pharmaceutical company plans to submit its application for drug approval to the Food and Drug Administration (FDA) within the next few months.

Dr. Leah Croll, an assistant professor of clinical neurology at the Lewis Katz School of Medicine at Temple University and a neurologist at Temple University Hospital, says this is an exciting time for anyone affected by Alzheimer’s disease.

“For many years, the Alzheimer’s drug development pipeline has been met with disappointment after disappointment, and I’m hopeful that we are now entering a new era. Any development is potentially meaningful,” Croll told Healthline.

The trial, which was conducted in over 1,100 individuals with early symptomatic Alzheimer’s disease, found that donanemab slowed cognitive and functional decline by 35% compared to the placebo.

Of those who took the drug 47% experienced no cognitive decline, according to a tool that measures disease severity, compared to 29% of those who took the placebo.

Those who took the drug also had 40% less decline than those who took the placebo and were better able to do daily activities like driving, hobbies, and talking about current events.

Participants who took donanemab had a 39% lower risk of progressing to the next stage of the disease.

Dr. Brendan Kelley, a neurologist and dementia specialist at UT Southwestern’s O’Donnell Brain Institute, says though the study was small, the implications of this drug are potentially enormous.

“This study demonstrated an effect for people treated early in the disease course, and this will have implications for improving our screening and accuracy in early diagnosis of Alzheimer’s disease,” Kelley told Healthline.

Donanemab works by removing abnormal buildup of a protein called amyloid from the brains in people with Alzheimer’s.

In people with Alzheimer’s, the amyloid protein builds up and turns into plaque.

Clumps of plaque can block brain synapses and lead to inflammation.

Over time, the plaque can spread throughout the brain as Alzheimer’s disease progresses.

To understand how the drug impacted amyloid build-up in the brain, the researchers measured amyloid plaque levels in the participants’ brains and found that 34% of participants were able to achieve amyloid clearance in 6 months and 71% achieved clearance at 12 months.

“The drug aims to prevent further accumulation of the amyloid protein, and the data from the study suggest that the drug was successful in reducing the amount of amyloid already accumulated in the brain for many patients in the research study,” says Kelley says.

The researchers also evaluated how levels of tau, another protein that accumulates in the brains of people with Alzheimer’s, affected the drug’s effectiveness.

They found that while people with higher tau levels still benefited from donanemab, it was more effective in people with lower tau levels.

“This information is consistent with what prior research has told us — that this class of drugs works best for people in the early stages of Alzheimer’s disease,” says Croll.

The rate of serious abnormalities was relatively low, however, there are a few safety concerns to be aware of.

The most common side effects were swelling (edema) and hemorrhage and some participants experienced headache and confusion.

In the trial, brain bleeding occurred in 31.4% of participants on donanemab and brain swelling occurred in 24% of participants on donanemab.

“For most patients, these side effect don’t produce substantial symptoms, but still, these are significant numbers and we will need to weigh the risks of this drug very carefully,” Croll said.

Kelley says it will be important to develop a strategy to monitor for these side effects and address any that may occur.

The study did find a link between the APOE genotype, a genetic risk factor for Alzheimer’s disease, and a person’s risk of developing these side effects, says Kelley.

“This may be an important factor to discuss with patients if using a drug like this is under consideration,” Kelley said.

According to Kelley, more studies are needed to determine if the slowing continues beyond the 18-month mark and how long a person should be on the medication.

It’ll also be important for researchers to monitor long-term use, too, so doctors can better understand the safety profile and evaluate the risks and benefits for each individual, he added.

“This is an emerging treatment area and there are still multiple factors that will be important to understand when to use this or similar medications, how to counsel patients about expectations and risks, and how to monitor for safety in using the medications,” Kelley said.

Eli Lilly and Company announced Wednesday that its experimental drug, donanemab, significantly slowed cognitive and functional decline in people with Alzheimer’s disease. The drug works be reducing sticky buildups of a protein called amyloid in the brains of people with the disease. Lilly plans to apply for drug approval from the FDA this quarter.