A new study is adding to evidence that people with multiple sclerosis can benefit from a type of stem cell transplant -- including some patients who are in a more advanced phase of the disease.
The research is the latest look at a potential alternative treatment for some patients with MS -- using their own blood stem cells to try to reboot their faulty immune systems.
Studies have found that the approach may benefit some patients in the earlier stages of MS. Now, the new findings suggest the same could be true of some patients in the second phase of the disease, known as secondary progressive MS.
Researchers found that among more than 2,000 Italian adults with secondary progressive MS, those who received the stem cell therapy fared better over five years than those taking standard medications.
Overall, 62% saw no worsening in their disability, compared with 46% of patients on medication. A small number -- 19% -- even maintained some improvement over five years, versus 4% in the medication group.
Experts said the findings add to evidence of the promise of the stem cell approach. But they also had important cautions.
For one, the study was not a clinical trial that directly tested stem cells against standard MS medications: It looked back at the records of patients treated for MS at various Italian medical centers somewhere between 1997 and 2019.
That means there could be "confounding factors" -- differences between patients who did or did not receive stem cell transplants -- that make it hard to draw conclusions, said Bruce Bebo, executive vice president of research for the National MS Society.
On top of that, patients taking MS medications did not receive the latest drugs approved for the disease. So it's unclear how those more targeted medications might stack up against stem cells.
Those are critical points, given that stem cell transplants are no small undertaking, according to researcher Dr. Matilde Inglese, head of the Multiple Sclerosis Center at the University of Genoa in Italy.
The whole process takes about three months, including a hospital stay and a period where patients have a severely compromised immune system. Ideally, Inglese said, eligible patients would get into a clinical trial testing stem cells against the best available MS drugs.
One such trial, called BEAT-MS, is underway in the United States.
MS is a neurological disorder caused by a misguided immune system attack on the protective sheath around nerve fibers in the spine and brain. The symptoms include vision problems, muscle weakness, numbness and difficulty with balance and coordination.
Most people with MS initially have the relapsing-remitting form, where symptoms flare for a time and then ease. Eventually, though, they typically transition to the secondary progressive phase, where their disability worsens over time.
At this point, Bebo said, there is "general agreement" that stem cell transplant is an option for people with aggressive relapsing-remitting MS that does not respond to medication.
In a study published last year, Inglese's team found that of patients with relapsing-remitting MS who received a transplant, 71% showed no worsening in their disability 10 years out.
At the time of that publication, Inglese said the general thinking around stem cell transplants is: the sooner the better: Inflammation in the brain and spine is at its height in the earlier stages of the disease, and that's the optimal time to intervene with stem cells.
However, patients in the latest study, published recently in the journal Neurology, had "active" secondary progressive MS -- meaning they still had evidence of ongoing inflammation.
Both Bebo and Inglese said that subset of patients might also stand to benefit from a stem cell transplant.
The principle behind the treatment is fairly simple: Stem cells from the bone marrow are the building blocks of the immune system, and the goal of the transplant is to eliminate the faulty immune system and start over, as Inglese explained.
The procedure involves removing stem cells from a patient's blood, then using powerful chemotherapy drugs to knock down the existing immune system.
Afterward, the stored stem cells are infused back into the patient, and the immune system rebuilds itself over time.
The idea is straightforward, but the process is no simple feat. It includes months of immune suppression that carry a risk of serious infections. And outside of a clinical trial, there's a big cost -- averaging $150,000, according to the National MS Society. Patients' out-of-pocket costs would vary based on their insurance coverage.
What's essential, Inglese said, is to receive care at a reputable medical center with experience in using stem cell transplants to treat MS.
The MS society warns that there are many self-described "stem cell clinics" out there, and patients should always consult their MS specialist on where to seek care.
The National MS Society has more on stem cell transplants.
SOURCES: Matilde Inglese, MD, PhD, head, Multiple Sclerosis Center, University of Genoa, Italy, and professor, neurology, radiology and neuroscience, Icahn School of Medicine at Mount Sinai, New York City; Bruce Bebo, PhD, executive vice president, research, National Multiple Sclerosis Society, New York City; Neurology, Dec. 21, 2022, online