THURSDAY, Jan. 29, 2009 (HealthDay News) -- Stem cell transplantation seems to stop and, in some cases, undo neurological damage in people with multiple sclerosis, a small study shows.
The trial involved just 21 patients, but a larger, randomized trial is under way in the United States, Canada and Brazil.
"This is the first trial for any phase of MS, whether early or later, of any therapy anywhere that has shown reversal of neurological disability," said study author Dr. Richard K. Burt, chief of the division of immunotherapy at the Northwestern University Feinberg School of Medicine in Chicago.
MS is a disease in which the immune system turns on the body and attacks myelin, the protective covering on nerve cells. The disease usually starts with a "relapse-remitting" phase, with alternating periods of flare-ups of symptoms and relatively peaceful spans. After a decade or so, however, most patients move into the more severe, secondary-progressive form of the disease.
"There is a need to find a means by which we can control the progression of MS, particularly in these patients who are not responding to FDA-approved therapies," said Patricia O'Looney, vice president of biomedical research at the National Multiple Sclerosis Society.
Treatments are clustered toward the relapse-remitting stage, with little available for the latter stage. "Generally, when you get to late progressive MS, nothing really works," Burt said.
The technique used in this study, autologous non-myeloablative hemopoietic stem cell transplantation, "resets" the immune system and is already used for secondary-progressive MS.
"This has primarily been used over the last 10 to 15 years in progressive MS patients, people who are doing terribly, and we have nothing to offer them," O'Looney explained. "There have been some fatalities associated with this aggressive protocol."
And success was limited.
But, for the new study, researchers tweaked the technique and moved it to relapse-remitting patients who were younger than in previous studies.
"This is a safer approach, and we do it earlier in the disease because people have less disability so it's safer again," Burt said.
The study involved 21 patients with the earlier stage of the disease who were not responding to treatment with interferon.
The procedure basically involves stripping the patient's body of its immune cells, and then repopulating the body with stem cells from the patient's bone marrow.
"You're trying to wipe out the immune system and then, with one's own cells, reconstitute it with the hope that the new cells will not target myelin. That's the theory, get rid of bad cells and reconstitute it with new cells from one's own body so hopefully they haven't been triggered yet to attach to myelin," O'Looney said.
Seventeen of the participants improved by at least one point on a scale used to measure disability. Five participants relapsed, then went into remission after more treatment.
After about three years, none of the patients' disease was progressing and 16 were no longer relapsing. And some experienced improvements, all without major side effects.
The findings were published online Jan. 30 in The Lancet Neurology and will appear in the March print issue of the journal.
Still, specialists are curbing their enthusiasm until further results are seen.
"We need to see a larger number of samples... and [we need to] know if the benefit they're seeing is due to the immune system being reset or because the immune system has been suppressed and will return as the way it was," O'Looney said.
Visit the National Multiple Sclerosis Society for more on this condition.