Novo Nordisk’s Old GLP-1 Drug May Slow Progression of Alzheimer’s Disease by Protecting the Brain, Study Finds

An ancient once-daily drug for diabetes and obesity Novo Nordisk A drug called liraglutide may slow the progression of Alzheimer’s disease by protecting patients’ brains, according to data from a mid-stage trial released Tuesday.

Novo Nordisk markets liraglutide as a diabetes and obesity drug under the brand names Victoza and Saxenda, respectively. Quarterly sales of these daily injections are falling as patients turn to the Danish manufacturer’s blockbuster weekly injections, Ozempic for diabetes and Wegovy for weight loss.

The findings add to growing evidence that the popular class of obesity and diabetes drugs called GLP-1 may have important health benefits beyond promoting weight loss and regulating blood sugar. With demand for GLP-1 having soared in the past two years, Novo Nordisk and its rival Elie Lilly They are studying the potential of their drugs in patients with chronic diseases ranging from fatty liver to sleep apnea.

Researchers at Imperial College London followed more than 200 British patients with mild to moderate Alzheimer’s disease who were randomly assigned to receive either a daily injection of liraglutide or a placebo. The study was partly funded by Novo Nordisk.

Patients who received liraglutide had an 18% slower decline in cognitive function after one year of treatment compared with those who received placebo.

The phase 2 trial showed that liraglutide slowed shrinkage of parts of the brain that are critical for memory, decision-making, learning and language by nearly 50% compared with placebo, according to MRI scans. Alzheimer’s disease often causes the brain to shrink as the disease progresses, as essential nerve cells break down and stop working properly.

The researchers presented the findings Tuesday at the Alzheimer’s Association International Conference in Philadelphia, the world’s largest meeting devoted to dementia research.

The new data demonstrate the diversity of therapies being developed or tested for Alzheimer’s disease, opening the door to new and potentially more personalized approaches to treating the disease, said Dr. Heather Snyder, vice president of medical and scientific relations at the Alzheimer’s Association.

Nearly 7 million Americans suffer from the disease, which is the fifth leading cause of death among adults over age 65, according to the Alzheimer’s Association. By 2050, the number of Alzheimer’s patients in the United States is expected to reach nearly 13 million.

The field of Alzheimer’s treatment has seen a major breakthrough in the past year, with two new drugs approved that slow the progression of the disease by targeting a toxic brain protein called amyloid, a hallmark of the disease. These include Eli Lilly’s Kisunla and Leqembi from Biogenic and Eisai.

Snyder told CNBC that Tuesday’s new data “opens the door” for scientists to explore combining these amyloid-targeting drugs with GLP-1s such as liraglutide.

It is worth noting that existing research shows that GLP-1s do not pose a risk of brain swelling or bleeding, two side effects associated with Leqembi and Kisunla. Patients receiving these amyloid-targeting treatments undergo routine MRIs to monitor for these side effects.

In the mid-stage trial, patients receiving liraglutide most commonly experienced gastrointestinal side effects associated with other GLP-1s, such as nausea.

This may be one of the advantages of using GLP-1 to treat Alzheimer’s patients – only a small fraction of whom currently receive drugs that target amyloid.

“Having a drug that has a very good safety profile and could be widely used is going to be a huge game changer for the field,” Dr. Paul Edison, professor of neuroscience at Imperial College London and lead author of the trial, told CNBC.

He said that GLP-1s, if approved for Alzheimer’s disease, “could be given virtually anywhere in the world without significant monitoring” for side effects, showing there is “great potential” for the drugs.

But more research is needed, he noted.

Edison is participating in Novo Nordisk’s Phase 3 “EVOKE” and “EVOKE+” trials. The ongoing EVOKE trial is testing semaglutide, the active ingredient in Wegovy and Ozempic, in nearly 2,000 patients with Alzheimer’s disease.

In a statement, Novo Nordisk said it welcomed independent research examining its GLP-1s as treatments for other diseases, but noted that the products are not currently approved for Alzheimer’s disease.

Measures of cognitive function and brain volume were not the primary aims of the study.

The main goal of the trial was to measure how much glucose the brain consumes, an important measure of cognitive function. As Alzheimer’s disease progresses, the metabolic rate of glucose in some parts of the brain declines.

Edison said he and his team felt they didn’t have enough participants in the trial to demonstrate a meaningful change in that rate. But he said it was encouraging that liraglutide met the study’s second goal of demonstrating a benefit on cognitive function, as well as another goal of a change in brain volume.

These results suggest that GLP-1s such as liraglutide may protect the brain, Edison noted.

“I think demonstrating cognitive improvement is key, because that’s what patients are interested in,” he told CNBC.

He said liraglutide likely does this in a variety of ways, including reducing inflammation in the brain, improving how nerve cells in the brain communicate, and reducing insulin resistance as well as reducing two hallmarks of Alzheimer’s disease: toxic proteins called amyloid plaque and tau.

Further research is needed to confirm this, Edison said.