No cure exists for ALS yet, but treatments can slow progression and extend survival

There is no cure for ALS. The disease remains progressive, meaning it will continue to damage motor neurons over time. However, two medications—riluzole and edaravone—have been shown to slow the rate of decline, and a third, sodium phenylbutyrate/ursodeoxycholic acid (marketed as Relyvrio), was approved in 2023. None of these drugs stop ALS or reverse damage already done. They extend survival by months and preserve function slightly longer, which matters to people living with the disease, but they do not halt progression.

The reason no cure exists is that ALS damages motor neurons in ways we still do not fully understand. Researchers have identified genetic mutations linked to some forms of ALS and discovered that misfolded proteins accumulate in nerve cells, but translating that knowledge into a treatment that restores dead neurons or prevents their death has proven far harder than early hopes suggested. Clinical trials for potential cures have failed repeatedly over the past two decades.

Key Takeaways

  • Riluzole and edaravone are the only medications proven to slow ALS progression, extending survival by a few months on average.
  • Relyvrio, approved in 2023, showed modest slowing of decline in a subset of people with early-stage ALS in clinical trials.
  • Supportive care—breathing assistance, feeding tubes, physical therapy—does not cure ALS but helps people live longer and more comfortably.
  • Multiple clinical trials are testing new approaches, including gene therapy and stem cell treatments, but none have yet proven effective in humans.

How riluzole and edaravone work differently

Riluzole has been used since 1995. It works by reducing the amount of glutamate, a chemical messenger in the brain and spinal cord that may damage motor neurons when it builds up. In clinical trials, riluzole extended median survival by about two to three months. Some people saw no benefit; others lived longer. There is no way to predict who will respond.

Riluzole is taken by mouth twice daily. Common side effects include dizziness, weakness, and nausea. It requires regular blood tests to monitor liver function. The drug costs several hundred dollars per month, though insurance often covers it.

Edaravone was approved in 2017. It works as an antioxidant, meaning it may protect neurons from damage caused by reactive oxygen molecules. In the clinical trial that led to approval, edaravone slowed decline by about 33 percent over six months in people with early-stage ALS—a smaller benefit than riluzole's, but meaningful. Like riluzole, it does not work for everyone.

Edaravone is given by intravenous infusion, either in a clinic or at home. The initial phase involves 14 daily infusions over two weeks, then a maintenance schedule of five infusions per month. This requires a port or regular IV access. Side effects include bruising, infection at the infusion site, and allergic reactions. It is more expensive than riluzole and requires more frequent medical contact.

What Relyvrio represents: a smaller step forward

Relyvrio combines two older drugs—sodium phenylbutyrate and ursodeoxycholic acid—that work on different pathways. Sodium phenylbutyrate may help cells clear misfolded proteins. Ursodeoxycholic acid is a bile acid that may reduce cell death. The combination was tested in people with early-stage ALS who had a specific genetic mutation (SOD1) or who carried the C9orf72 repeat expansion, another genetic form.

In the trial, Relyvrio slowed decline by about 25 percent over six months in the SOD1 group. The benefit in the C9orf72 group was smaller and less certain. For people without these genetic forms—the majority of ALS cases—Relyvrio has not been tested and is not recommended.

Relyvrio is taken by mouth four times daily. It can cause diarrhea, nausea, and abdominal pain. It costs thousands of dollars per month. Because it only helps a subset of people with specific genetic mutations, genetic testing is necessary before starting it.

Why clinical trials for ALS cures have failed

Over the past 20 years, dozens of drugs that looked promising in laboratory and animal studies have failed in human trials. Compounds that protected neurons in a dish or slowed disease in mice did not slow it in people. Some trials were stopped early because the drug was not working. Others completed but showed no benefit.

The reasons are complex. ALS in humans is more complicated than ALS in mice. The blood-brain barrier—a filter that protects the brain—blocks many drugs from reaching motor neurons. Some compounds that seemed to target the root cause turned out to affect many other cell processes, causing side effects that outweighed any benefit. And ALS itself is not one disease: genetic ALS, sporadic ALS, and ALS linked to different mutations may require different treatments.

This history does not mean a cure is impossible, but it shows why researchers are cautious about claims. A drug that works in early trials may fail in larger, longer studies. The gap between "slows decline" and "cures" remains vast.

Experimental treatments currently in trials

Gene therapy is being tested in people with SOD1 mutations. The approach involves delivering a modified gene into the spinal cord that either corrects the mutation or silences the faulty gene. Early results in a small number of people have been encouraging enough to continue trials, but it is too early to say whether this will work broadly or safely in larger groups.

Antisense oligonucleotides are short pieces of genetic material designed to silence genes that produce toxic proteins. One drug in this class, tofersen, targets SOD1 mutations and has shown modest slowing of decline in trials. Another, nusinersen, targets SMN (survival motor neuron) and is used in spinal muscular atrophy, a related but distinct disease. Researchers are testing whether similar approaches work in other genetic forms of ALS.

Stem cell treatments have been tested in small trials, with the idea that new cells might replace damaged motor neurons or support surviving ones. Results so far have not shown clear benefit, and safety concerns remain about tumor formation and immune rejection. Research continues, but no stem cell treatment is proven effective.

Immunotherapy is being explored because some evidence suggests the immune system contributes to motor neuron death in ALS. Trials are testing whether drugs that modify immune function can slow progression. Results are still preliminary.

Supportive care extends life and improves quality of life

While medications slow decline, supportive care—sometimes called palliative care—often extends survival more than any single drug. This includes respiratory support, nutritional support, physical therapy, and symptom management.

Respiratory support begins with non-invasive ventilation: a mask connected to a machine that helps you breathe, used at night or during the day as needed. As the disease progresses, some people choose a tracheostomy—a surgical opening in the windpipe connected to a ventilator. Others choose not to pursue mechanical ventilation. Either way, this decision is made with a doctor and family, not forced by the disease.

Feeding tubes become necessary when swallowing becomes unsafe or eating takes too much effort. A tube placed directly into the stomach (a PEG tube) allows nutrition without the risk of food entering the lungs. People can still eat by mouth for pleasure if they wish.

Physical and occupational therapy help maintain strength and function as long as possible and adapt the home and daily routines as abilities change. Speech therapy addresses changes in voice and swallowing.

The difference between slowing and stopping

It is important to understand what current medications actually do. Riluzole, edaravone, and Relyvrio slow the rate at which ALS progresses. They do not stop it. A person taking one of these drugs will still gradually lose strength and function. They will do so somewhat more slowly than they would without the drug, but the disease continues.

This distinction matters because it shapes realistic expectations. If someone is told a drug will "extend survival by three months," that means the median person in the trial lived three months longer than the control group—not that everyone lived three months longer, and not that the drug halted the disease. Some people in trials saw no benefit. Others saw more.

A cure would stop the disease entirely, restore dead neurons, or prevent the disease from developing in the first place. None of those outcomes has been achieved. The medications we have are tools that buy time, and for people with ALS, time matters. But they are not cures.

Frequently Asked Questions

Could a cure be found in the next few years?

It is possible but not certain. Gene therapy and antisense approaches show early promise in specific genetic forms of ALS, and trials are ongoing. However, the history of ALS research shows that promising early results often do not translate to effective treatments in larger studies. A breakthrough is not imminent, but research is active.

Should someone with ALS start riluzole or edaravone even if the benefit is small?

That is a decision to make with a neurologist. Both drugs have side effects and costs. For some people, extending survival by a few months is worth it. For others, the burden of treatment outweighs the benefit. There is no single right answer, and the choice depends on individual values and circumstances.

Is there any evidence that diet, supplements, or alternative treatments slow ALS?

No rigorous clinical trials have shown that diet, supplements, or alternative therapies slow ALS progression. Some people report feeling better on certain regimens, which may reflect placebo effect or improved overall health. Always discuss any supplements or alternative approaches with your neurologist, as some can interact with ALS medications or cause harm.

What happens if someone refuses all medications and supportive care?

ALS will progress without treatment. Without respiratory support, death typically occurs when the muscles controlling breathing fail, usually within two to five years of symptom onset. With supportive care but no disease-slowing medications, survival is longer. The choice to pursue or decline any treatment is the person's own.

Are there different treatments for genetic versus sporadic ALS?

Relyvrio is only tested and recommended for people with specific genetic mutations (SOD1, C9orf72). Riluzole and edaravone work for both genetic and sporadic ALS. Gene therapy and antisense treatments are being developed for specific genetic forms. If you have ALS, genetic testing can identify whether a mutation-specific treatment might help.