Stiff Person Syndrome: CAR-T Trial Offers Hope for Céline Dion’s Condition
US neurologists at the Mayo Clinic reported on November 9, 2026 that CAR-T cell therapy brought dramatic improvements to patients with stiff person syndrome, the rare autoimmune condition affecting singer Céline Dion. Some patients returned to work. Doctors say it is too early to know if gains last.
A medical breakthrough offers hope to people with stiff person syndrome, the rare autoimmune condition affecting singer Céline Dion, after Mayo Clinic neurologists in the US reported dramatic improvements in patients given CAR-T cell therapy. The results were published in the journal Jama Neurology and reported on November 9, 2026.
There is no cure for the disease. Stiff person syndrome (SPS) attacks the central nervous system and can cause severe rigidity throughout the body and painful muscle spasms.
Doctors at the Mayo Clinic said patients who once needed help with basic daily tasks and struggled to walk have regained everyday life. Some have returned to work and resumed hobbies.
How the treatment works
CAR-T therapy is already used to treat cancer. It reprogrammes a patient's immune cells to fight disease. In the SPS study, patients' own T cells, a type of immune cell, were extracted and engineered to wipe out the cells causing the illness.
The treatment was a single dose. The new study could now lead to larger trials in people with SPS.
What patients and doctors said
Dr Anastasia Zekeridou, a neurologist and researcher at Mayo Clinic in Rochester, said: "What was most striking was the degree of improvement we saw in some patients." She said existing treatments may ease symptoms, but patients "very rarely" return to their previous level of function.
She added that the early results are "very encouraging", and the key question is whether the improvements will be sustained over time.
Jonathan Walden, one of the trial patients, had reached the point where walking and basic tasks required help from his family. "I can go to work every single day. I can do everything I did before. I go hunting; I can go fishing," he said. "I have not had one episode since receiving treatment."
Shari St Germain, diagnosed in 2021, had severe leg cramps and difficulty walking. Later, sudden noises led to muscle rigidity and falls. By 2024, standard treatments were no longer controlling her symptoms.
After CAR-T, she walked on a treadmill again. "I just walked for seven minutes on the treadmill," she said. Every day, she said, "just gets better and better".
Dr Sean Pittock, chair of the department of neurology at Mayo Clinic, said the results "offer tremendous hope", not only for people with SPS but potentially for patients with other immune-mediated neurologic conditions. "There is still much we need to learn, but this opens an exciting new avenue for the field," he said.
About the condition
SPS affects an estimated 8,000 people worldwide. It affects twice as many women as men, and most people develop symptoms between the ages of 20 and 60.
Dion announced her diagnosis in December 2022. In an Instagram video, she told fans the condition had affected "every aspect of my daily life", including harming her voice.
Yasmin Sheikh, head of policy and public affairs at the blood cancer charity Anthony Nolan, which was not involved in the trial, called the research "an exciting development". She said it provides more evidence that CAR-T therapies could have uses beyond blood cancer.
