Immunosuppression, Stem Cells Halt MS

HDIT/HCT could induce sustained remission and improvements in MS.

There may be good news about multiple sclerosis (MS) treatment. A phase 2 clinical trial of high-dose immunosuppressive therapy and a person’s own hematopoietic cell transplantation (HDIT/HCT) in relapsing-remitting MS (RRMS) has yielded results at the 3-year mark. The treatment sustained remission and improved neurological function.

More than 2.3 million persons are affected by MS worldwide. RRMS is the most common type of MS. Most persons with RRMS taking approved treatments still may have breakthrough disease and continue to decline neurologically. Better treatments for patients with MS are greatly needed.

Whether HDIT/HCT could induce sustained remission and neurological improvements, outcomes that are far better than those produced by current treatments, was tested by an internationally based group of researchers from the United States, the UK, and Canada. They studied the treatment in 25 patients with RRMS, age 18 to 60 years; 24 received the treatment and 1 did not. Evaluations are planned up to 5 years.

Participants were given high-dose treatment with carmustine, etoposide, cytarabine, melphalan, and rabbit antithymocyte globulin prior to the cell transplant. This was effectively high-dose chemotherapy that destroyed their immune cells so they could be replaced by the stem cells. The investigators selected autologous peripheral blood stem cell grafts based on the presence of CD34+.

The overall patient percentage without an increase in disability was 78.4% after 3 years. The percentage of patients without MS progression was 90.9%, and 86.3% went without relapse of their MS symptoms. The treatment induced only expected toxic effects of the immunosuppression, including infections and GI problems.

In their report, the authors concluded,“At 3 years, HDIT/HCT without maintenance therapy was effective for inducing sustained remission of active RRMS and was associated with improvements in neurologic function. Treatment was associated with few serious early complications or unexpected adverse events.”

National Institute of Allergy and Infectious Diseases (NIAID) Director Anthony S. Fauci, MD, remarked on the trial results, stating, “These promising results support the need for future studies to further evaluate the benefits and risks of HDIT/HCT and directly compare this treatment strategy to current MS therapies. If the findings from this study are confirmed, HDIT/HCT may become a potential therapeutic option for people with this often-debilitating disease, particularly those who have not been helped by standard treatments.”

Daniel Rotrosen, MD, director of the NIAID’s Division of Allergy, Immunology and Transplantation, noted that the results indicate that HDIT/HCT appears to be more effective than previous treatments, stating, “Notably, participants did not receive any MS drugs after transplant, yet most remained in remission after three years. In contrast, other studies have shown that the best alternative MS treatments induce much shorter remissions and require long-term use of immunosuppressive drugs that can cause serious side effects.”

The results of this study will further assist with the development of a larger Phase III trial to further evaluate the treatment. Five-year results of this study also will provide even more information about MS outcomes in the study participants.

The study appeared in the December 29th issue of JAMA Neurology.¹

Key points

• HDIT/HCT could induce sustained remission and neurological improvements in patients with MS.

• Initial MS outcomes produced by HDIT/HCT appear better than those produced by current approved treatments.

• Further study of HDIT/HCT in more patients with MS is needed.

References:

1. Nash RA, Hutton GJ, Racke MK, et al. High-dose immunosuppressive therapy and autologous hematopoietic cell transplantation for relapsing-remitting multiple sclerosis (HALT-MS): a 3-year interim report. JAMA Neurol. 2014 Dec 29. doi: 10.1001/jamaneurol.2014.3780. [Epub ahead of print]