• People with multiple sclerosis (MS) who undergo hematopoietic stem cell transplantation (HSCT) may reduce their rate of relapse, according to a recent study.
• Researchers found that annual relapse rates dropped from 1.1 per person to zero following HSCT.
• The risks of stem cell transplantation were highest among participants with a high number of disabilities at the time of the procedure.

New evidence shows that stem cell transplantation is a promising tool for treating aggressive MS. Better outcomes and a stronger safety profile were seen among those experiencing lower disability levels at the time of the procedure.

“This study attests to the long-term effectiveness and safety of aHSCT [autologous HSCT] for the treatment of aggressive MS,” the researchers concluded. “Still risks are real, including mortality, but overall morbidity and mortality is low (2.8 percent) and similar to other reported studies.”

What Is Stem Cell Transplantation?

Stem cell transplantations for people with MS have been gaining interest in recent years, due to their ability to “reset” the immune system. MS is caused by the immune system mistakenly attacking the myelin sheath surrounding a person’s nerve fibers in their spinal cord, brain, and optic nerve.

A person receiving aHSCT first undergoes chemotherapy, which destroys their immune system. Next, stem cells previously taken from their own bodies are reintroduced to revive their immune system.

Researchers from Canada launched a study to evaluate the safety of the procedure and its long-term effects on disease remission. They presented their findings on Feb. 25 at the 2022 Americas Committee for Treatment and Research in Multiple Sclerosis Forum.

The study authors reviewed the outcomes of 72 people with MS who underwent autologous HSCT from Oct. 2001 to Feb. 2021. Sixty-two of the study participants had relapsing-remitting MS, while eight had secondary progressive MS and two had primary progressive MS.

Relapse Rate Dropped to Zero After Transplant

Study participants had all undergone HSCT, between eight months and 20 years prior to the study. Researchers assessed whether any of the participants had faced any new clinical relapses (a return of symptoms) following transplantation. They also looked for new MRI lesions, potential safety risks, and survival outcomes with the HSCT procedure.

The researchers found that none of the participants had relapsed after receiving their transplants. However, two people died: one at 27 days post-procedure and the other more than five years after the stem cell transplant.

The research team calculated that prior to undergoing transplants, participants had an annual rate of 1.1 relapses per person. That rate dropped to zero after the procedure. In addition, none of the study participants received disease-modifying treatments (DMTs) following their HSCT. While MRI scans were not consistently performed for every participant, the available imaging suggested participants had no new lesions after their transplants.

The researchers also used the Expanded Disability Status Scale to measure worsening disability as time passed. Their findings showed that participants with a small number of disabilities at the time of the procedure showed better disability outcomes than people with a high number of disabilities before the transplant.

Costs and Risks of Stem Cell Transplants

Researchers highlighted the effectiveness of the procedure but noted that “proper patient selection is important, with better results seen in patients who have acquired less disability at the time of aHSCT.”

According to the National Multiple Sclerosis Society, HSCT comes with treatment risks, including the chance of serious infections.

Researchers also noted other benefits of an HSCT. “There is also long-term monetary and safety value of not requiring the regular use of DMT.”

“The average total cost of care for inpatient aHSCT is $150,000,” according to the National Multiple Sclerosis Society. “However, widespread variations in cost exist across the United States with a variety of factors determining a patient's out-of-pocket spending. For insured patients, out-of-pocket spending for inpatient aHSCT is generally far less.”