Two patients with severe autoimmune disease remain relapse-free for over 15 years after stem cell transplant
by Sanjukta Mondal, Medical Xpress
edited by Sadie Harley, reviewed by Robert Egan
Neuromyelitis optica spectrum disorder (NMOSD) is a rare autoimmune condition in which the body's own defenses turn against the optic nerves and spinal cord. This confusion leads to inflammation that can rob people of their vision, disrupt something as basic as bladder or bowel control, and in some cases even cause paralysis of the arms and legs.
More than a decade ago, two people with potentially fatal NMOSD underwent a procedure called an allogeneic hematopoietic stem cell transplant (alloHCT), in which they received healthy stem cells from a donor to replace their own damaged or diseased cells.
After tracking the patients for 15 years, the researchers published a case report with a positive update. Both patients remained completely free of disease attacks or relapses for 15 and 16 years, even without continued immunosuppressive treatment.
After stem cell transplantation, AQP4-IgG, the disease-causing antibody, became undetectable and remained negative throughout the follow-up period. The researchers also saw an improvement in both patients' quality of life after the treatment.
The findings are published in Med.
Replacing the notorious bodies
In many patients, NMOSD is driven by AQP4-IgG antibodies, which mistakenly attack support cells in the nervous system, leading to the loss of myelin—the protective coating around nerve fibers—and causing serious neurological symptoms. Even with today's therapies, some NMO patients still suffer relapses, with 60%–98% of patients experiencing repeated attacks that can result in permanent disability.
So far, no approved therapy lets patients go treatment-free while still keeping the disease under control and clearing the problematic antibodies from the system.
In search of new ways to address this issue, the researchers turned to allogeneic hematopoietic stem cell transplant (alloHCT), which has emerged over the past three decades as a highly effective treatment option for autoimmune diseases.
The team involved in this study selected two patients who had a very severe form of NMOSD that did not respond to standard treatments, including earlier attempts to transplant their own stem cells. The patients were treated with alloHCT in 2009 and 2010.
Before receiving stem cells from healthy donors, the patients were treated with the chemotherapy drugs fludarabine and treosulfan to eliminate their existing, malfunctioning immune cells. They also received rituximab, a monoclonal antibody therapy that further depleted B cells, the cells responsible for producing the harmful NMO antibodies.
ver the next 16 and 15 years, doctors performed regular neurological checkups, MRI scans of the brain and spinal cord, and antibody testing to track the changes induced by the treatment.
The researchers found that the two patients with a severe, hard-to-treat form of NMO achieved long-term remission lasting more than 15 years after receiving donor stem cell transplants. The disease-causing AQP4-IgG antibodies disappeared from their blood after the transplant and remained undetectable throughout follow-up, something standard treatments usually cannot achieve.
Tests confirmed that the patients' original, faulty immune systems had been completely replaced by healthy donor cells.
The patients also reported a better quality of life. One patient saw a major improvement in his physical abilities and became a father of two. Even though the other patient still had some disability from damage that happened before the transplant, she also reported being able to do things she wasn't able to do before.
The researchers believe these findings provide proof of concept that alloHCT can significantly change the course of the disease, bringing lasting improvement in selected NMO cases. Further studies with larger cohorts are needed to better define patient selection, safety and the long-term benefit of this treatment.
Written for you by our author Sanjukta Mondal, edited by Sadie Harley, and fact-checked and reviewed by Robert Egan—this article is the result of careful human work. We rely on readers like you to keep independent science journalism alive. If this reporting matters to you, please consider a donation (especially monthly). You'll get an ad-free account as a thank-you.
Publication details
Giorgio Orofino et al, Long-term remission of neuromyelitis optica with allogeneic hematopoietic stem cell transplant, Med (2026). DOI: 10.1016/j.medj.2026.101179
Journal information: Med
Sanjukta Mondal
Master's in Chemistry. Freelance science journalist and communicator. Published in Chemistry World, BioSpace, and The Hindu. Full profile →
Sadie Harley
BSc Life Sciences & Ecology. Microbiology lab background with pharmaceutical news experience in oil, gas, and renewable industries. Full profile →
Robert Egan
Bachelor's in mathematical biology, Master's in creative writing. Well-traveled with unique perspectives on science and language. Full profile →