For decades, the general consensus among neurologists and neuroscientists has been that ALS treatments would only be able to slow down or stop further progression of the disease. Function that had already been lost would probably not be recovered.
But now, evidence is emerging that not only is functional improvement possible, it’s happening for some people with SOD1-ALS who have been treated with Qalsody® (tofersen).
Qalsody is a genetically targeted treatment approved by the U.S. Food and Drug Administration (FDA) in 2023 specifically for people with ALS caused by a mutation in the SOD1 gene, also known as SOD1-ALS. The therapy is injected directly into the spinal canal to stop toxic SOD1 proteins from being made.
Real-World Results
A new paper published last week in the Annals of Clinical and Translational Neurology shows that Qalsody treatment helps stabilize ALS and leads to “meaningful preservation of function and suggestions of sustained improvement in neurologic function in some patients.”
The paper is based on the real-world experiences of seven people diagnosed with SOD1-ALS who were treated with Qalsody at Washington University in Saint Louis from November 2021 to February 2024.

During the treatment period, all participants experienced “robust and sustained declines” in blood levels of a protein called neurofilament light (NfL). NfL levels are high when neurons have been damaged or are degenerating, so decreases in NfL are associated with less ALS progression. The researchers estimated that the participants progressed an estimated 52% slower than expected following treatment with Qalsody.
In addition, muscle strength improved for five of the study participants. Participants also gained, on average, a little more than five points on the functional independence measure motor score, a “notable improvement in functional independence,” according to the researchers.
“This study, led by Dr. Sean Smith in our group, highlights the substantial functional and clinical benefits associated with use of [Qalsody] in a group of ALS patients with SOD1 mutations in a ‘real world’/clinical setting,” said senior author Dr. Robert Bucelli, professor of neurology at the Washington University School of Medicine and ALS Center co-director.
“Dr. Smith’s background in physical medicine and rehabilitation also helped our group identify a number of potentially useful outcome measures. Historically, these measures had been limited to use in neurologic conditions for which recovery was expected/possible with the appropriate intervention, and therefore haven’t been utilized in ALS trials. The demonstrated utility of these measures in this publication will force investigators to reconsider outcome measures in clinical studies as additional ALS therapies with substantial clinical benefit are (hopefully) identified.”
Hope for the Future

For people diagnosed with SOD1-ALS like Cory Mosley, results like these mean time—time to see his seven-year-old daughter, Willa, grow up.
“One of the more emotional moments since I’ve been diagnosed was doing the math on how much time I have left with my daughter,” Cory said. “She was six at the time. So, thinking that I may not see her graduate high school, that was kind of upsetting.”
Cory has witnessed firsthand the devastating impact SOD1-ALS has on families. Thirty-nine of his relatives across three generations have been diagnosed with the disease, including his mother, who passed away seven years ago. But after starting treatment with Qalsody in February 2024, he is facing the future with something others in his family did not have years ago: hope.
“Up until recently, there was no real way to do anything about it. So, you just kind of go through life wondering when it’s going to hit. But now it feels a little different. There’s some treatment that is showing promise, that’s working for me. It’s working for other members of my family,” he said.

Disease stabilization and functional improvements also have been reported by clinicians conducting similar research in Europe. In Italy, out of 17 people with SOD1-ALS who were treated for at least four years, nine substantially stabilized or slightly improved, while four had such a slow progression that their disease trajectory did not allow the researchers to identify changes.
Published data from Germany showed that five people who took part in a Qalsody early access program began to stabilize or improve after four to six weeks of treatment. One person improved by nine ALSFRS-R points, an outcome the researchers directly attributed to the treatment.
“When we first invested in the antisense technology that led to Qalsody 20 years ago, it was a gamble. Something like this had never been tried in the neurodegenerative disease space before,” Dr. Dave said. “Now, Qalsody is changing the way we think about the future of ALS treatment because we know that improvement in function—recovery—is possible. This is not just hope for people living with SOD1-ALS, but for the entire ALS community.”
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Comments
How do i get this treatment?
Wil, please discuss this treatment with your doctor.
This is fantastic news! I am so hopeful that this treatment will be available soon for all who have ALS. These results are one reason I have supported this important and impactful research since my brother died of ALS in 2014. I plan to continue giving until I’m no longer able.
Thank you for sharing this hopeful and groundbreaking news!
I am so happy that Qalsody is working. My husband had 9 infusions and we were seeing his neurofillaments decline. When we tried to qualify for it drug as Tofersen, he was asymptomatic. Due to many errors in coordination, by the time he received it, symptoms had surfaced and his neurofillaments were rising and he was declined. His brother, father, uncle and grandfather passed of SOD1 ALS before him. I cannot appeal enough to say the key is EARLY intervention with this drug. He might be here if there hadn't been months of delay. But, for the future of his family, I sure hope these advances continue. The medical community needs to treat this with a true sense of urgency as every single day with ALS matters and if you are positive for this gene, standard of care should be immediate use of this drug. Although I might sound negative, I sincerely appreciate the positive news and the renewed hope for all families impacted by ALS, not just SOD1 ALS.
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