Destroying bone marrow with chemotherapy and replacing the marrow with stem cells may help stabilize aggressive forms of multiple sclerosis (MS), according to a new study.

Twenty-five percent of patients who received the treatment, called hemopoietic stem cell transplantation, in the new study didn't experience a worsening of aggressive multiple sclerosis 15 years later, as would be normally expected, said study researcher Dr. Vasilios Kimiskidis. Kimiskidis is affiliated with Aristotle University of Thessaloniki Medical School in Greece.

But the results are from an early pilot study, meant only to investigate the feasibility of the treatment for people with severe multiple sclerosis, Kimiskidis said. That means clinical trials still need to be done to see whether the treatment is a better option than current treatments for aggressive multiple sclerosis, he said.

The treatment "is not a therapy for patients with [multiple sclerosis ] at large, but should be restricted for rapidly deteriorating cases," Kimiskidis told MyHealthNewsDaily.

Multiple sclerosis is a disease where the body's immune system destroys the protective layer surrounding the nerves, hampering communication between the brain and the body, according to the Mayo Clinic. It affects about 250,000 to 350,000 people in the United States, according to the National institutes of Health.

The study will be published March 22 in the journal Neurology. Kimiskidis and colleagues have received funding from or serve as consultants for a number of pharmaceutical companies, including GlaxoSmithKline, Pfizer Inc., GENESIS Pharma S.A., Novartis and Roche.

Stem cell effectiveness

Patients who underwent the treatment in the study were first administered chemotherapy to kill all the body's blood cells, including immune cells thought to be attacking the central nervous system. Then, bone marrow stem cells were removed from each patient and transplanted back into his or her body to replace the destroyed blood cells and revamp the immune system, the study said.

Kimiskidis and his colleagues administered the stem-cell transplant to 35 people, who were then followed for an average of 11 years, starting in 1995. Everyone in the study had aggressive multiple sclerosis and had tried other treatments to no avail, and scored a 6 on the multiple sclerosis severity scale.

(A healthy person with normal neurological function would score a 0 on the scale, whereas a person who died from multiple sclerosis would score a 10. A 6 means the person can walk with a cane or crutches, and a 7 means the person must use a wheelchair.)

Sixteen people, or 46 percent of the patients who received the treatment, experienced a one-point improvement on the multiple sclerosis severity scale, which lasted about two years, according to the study.

However, two people died from complications from the transplant, at two months after the transplant and at 2.5 years after the transplant, the study said.

"In future studies, strict adherence to proper patient selection criteria, according to currently existing guidelines, can help lowering this risk [of death from the treatment] even further," Kimiskidis said.

Other treatments

Right now, patients with aggressive multiple sclerosis are treated using the "escalation approach," he said. That means they are treated first with a drug that regulates the immune system; if or when that drug becomes ineffective, they are treated with a second drug that also regulates the immune system.

It's not yet known if the stem-cell treatment works better than current drugs, which is why future comparative treatment trials are needed, Kimiskidis said.

While the treatment could help a select group of people with very aggressive multiple sclerosis, there are a number of other drugs available today that are also promising for treating the disease, said Dr. Aaron Miller, professor of neurology at Mt. Sinai Medical Center in New York, who was not involved with the study.

"I think that it's an approach that is worth looking at, especially a few years ago, and it still may be worth considering in very rare patients, but don't think it'll enter mainstream MS therapy," Miller told MyHealthNewsDaily.

The therapy is potentially dangerous, since two patients died in the study, "so it's not something to be undertaken except in dire circumstances," he said.

Pass it on: A new stem cell treatment helped improve mobility in people with aggressive multiple sclerosis, though further study is needed on the approach.

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