Experimental ALS Drug Slows Disease Progression in Preliminary Study


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Key Takeaways

  • A new drug to treat ALS slowed the progression of the disease in patients in a new study.
  • The difference between patients who took the drug and those who took a placebo was small but significant.
  • About 12,000 to 15,000 people in the U.S. have ALS.

An experimental drug may help slow the progression of the brain disease amyotrophic lateral sclerosis (ALS), according to a new study from the New England Journal of Medicine. Treatment options for ALS patients are very limited, so researchers hope this drug can potentially serve as a complementary therapy.

ALS is a group of rare neurological diseases that involve the nerve cells responsible for controlling voluntary muscle movements like chewing, walking, and talking, according to the National Institute of Neurological Disorders and Stroke (NINDS). The disease is progressive, meaning the symptoms get worse over time, and there is currently no cure. Every year, about 5,000 people are diagnosed with ALS in the United States.

For the study, which was published on September 3, researchers tested a new medication, which is a combination of sodium phenylbutyrate–taurursodiol called AMX0035, on patients with ALS. Of those patients, 89 were given the new medication, while 48 were given a placebo. The researchers then tracked the patients for 24 weeks and measured the progression of their disease using the Revised Amyotrophic Lateral Sclerosis Functional Rating Scale (ALSFRS-R), a measurement of the severity of a patient’s ALS. 

At the end of the study, patients who took AMX0035 had a slower functional decline than those who took the placebo. Researchers called for longer and larger trials as the next step for the drug.

“This is an important step forward and very hopeful news for people with ALS and their families,” lead study author Sabrina Paganoni, MD, PhD, an assistant professor at Harvard Medical School and Spaulding Rehabilitation Hospital, tells Verywell. “Patients who were treated with AMX0035 retained physical function longer than those who received placebo. This means that they retained more independence with activities of daily living that are important to patients such as the ability to walk, to talk, and to swallow food.” 

What This Means For You

The trial for AMX0035 to treat ALS is still ongoing. But, with time, this new medication may end up becoming another mainstay of ALS treatment. 

Understanding ALS

When a patient has ALS, they experience a gradual deterioration of their motor neurons, or nerve cells providing communication from the brain to the spinal cord and muscles, NINDS explains. In ALS, motor neurons in the brain and spinal cord degenerate or die and stop sending messages to the muscles. As a result, the muscles gradually get weaker, twitch, and waste away. Over time, the brain is no longer able to control voluntary muscle movements.

“ALS is a very hard disease for patients and family,” Amit Sachdev, MD, medical director in the division of neuromuscular medicine at Michigan State University, tells Verywell.

Eventually, a person with ALS will lose the ability to speak, eat, move, and breathe, the NINDS says.

Most people with ALS die from respiratory failure within 3 to 5 years from when the symptoms first appear, according to the NINDS. About 10% of people with the diagnosis will survive for 10 or more years.

How AMX0035 Can Help

There is currently no effective treatment to halt or reverse the progression of the disease. However, there are treatments that can help a patient control their symptoms and make them more comfortable. ALS patients are typically given a combination of medications with potential physical therapy and nutritional support.

The Food and Drug Administration (FDA) approved the drugs riluzole (Rilutek) and edaravone (Radicava) to treat ALS. Riluzole can help reduce damage to motor neurons and extend a person’s survival by a few months, while edaravone can help slow the decline of a patient’s daily functioning.

AMX0035 isn’t a replacement therapy for existing medications, Paganoni says. Instead, it’s thought to be able to serve as a complementary therapy.

Sabrina Paganoni, MD, PhD

This tells us that we might need a combination of different treatments to fight ALS most effectively.

— Sabrina Paganoni, MD, PhD

In this latest study, most patients were already taking riluzole, edaravone, or both. “AMX0035 provided added benefit on top of standard of care,” Paganoni says. “In addition, the mechanisms of action of these drugs are different. This tells us that we might need a combination of different treatments to fight ALS most effectively.”

No single drug has been created that halts the progression of ALS entirely, but experts are hopeful for the future of ALS treatment. “New treatments are needed,” Sachdev says. “This medication would be a good step.”

However, Sachdev cautions, AMX0035 is not a miracle cure for ALS. “In this trial, patients continued to steadily decline," he says. "Their decline slowed but only modestly."

On the ALSFRS-R scale, study participants who took AMX0035 rated, on average, 2.32 points higher on a 0-48 scale that breaks down a patient's ability to independently complete 12 daily activities, such as talking, walking, and writing.

What Happens Next With AMX0035

This particular study was relatively short, making it unclear if the drug could delay a person’s death and give them more control over muscle movements for additional months, Sachdev says. However, the trial is ongoing. 

Participants who completed the trial were given the option to take AMX0035 long-term. “This extension is important because it will teach us about the impact of the drug on survival,” Paganoni says. “We have been following participants for as long as three years now.”

Paganoni is hopeful about the future of ALS treatment.

“Slowing disease is an important goal in a rapidly progressive disease like ALS because slower disease means longer retention of physical function and more independence with activities of daily living,” she says. “We hope that, in the future, we will be able to find a medication or a combination of medications that can completely stop or even reverse the disease. In the meantime, every success story such as this one tells us that we are on the right path.”

5 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Paganoni S, Macklin E, Hendrix S, et al. Trial of sodium phenylbutyrate–taurursodiol for amyotrophic lateral sclerosisN Engl J Med. 2020;383(10):919-930. doi:10.1056/nejmoa1916945

  2. National Institute of Neurological Disorders and Stroke. Amyotrophic Lateral Sclerosis (ALS) Fact Sheet.

  3. Centers for Disease Control and Prevention. What is ALS?

  4. U.S. Food and Drug Administration. Rilutek Full Prescribing Information.

  5. U.S. Food and Drug Administration. FDA Approves Drug to Treat ALS.

By Korin Miller
Korin Miller is a health and lifestyle journalist who has been published in The Washington Post, Prevention, SELF, Women's Health, The Bump, and Yahoo, among other outlets.