A new study shows intense immunosuppression followed by a hematopoietic stem cell transplant may prevent disability linked to multiple sclerosis from getting worse in 71 percent of people with relapsing-remitting MS for up to 10 years after the treatment. The study also found that improvements in disability were sustained 10 years after treatment. Additionally, more than half of the people with the secondary progressive form of MS experienced no worsening of their symptoms 10 years after a transplant.

The study involved autologous hematopoietic stem cell transplants, which use healthy blood stem cells from the participant’s own body to replace diseased cells. The study looked at 210 people with MS who received stem cell transplants from 1997 to 2019. Their average age was 35. Of those people, 122 had relapsing-remitting MS and 86 had secondary progressive MS and two had primary progressive MS. Researchers assessed participants at six months, five years, and 10 years after their transplants.

Five years into the study, researchers found that 80 percent of the people experienced no worsening of their MS disability. At the 10-year mark, 66 percent still had not experienced a worsening of disability.

When looking at just the people with the most common form of MS, researchers found 86 percent of them experienced no worsening of their disability five years after their transplant. Ten years later, 71 percent still experienced no worsening of their disability.

Also, people with progressive MS benefited from stem cell transplants. Researchers found that 71 percent of the people with this type of MS experienced no worsening of their disability five years after their transplants. Ten years later, 57 percent experienced no worsening of their disability.

Limitations of the study include that it was retrospective, did not include a control group and the clinicians who helped measure participants’ disability were aware that they had received stem cell transplants, so that could have led to bias. The researchers said these limitations will be addressed in future research.

The study was published in Neurology.