Importance
Autologous hematopoietic stem cell transplant (AHSCT) for multiple sclerosis has gained increasing interest in recent years. Despite the availability of many US Food and Drug Administration–approved disease-modifying therapies, some patients do not respond adequately and others may have very early aggressive disease that prompts consideration of alternative, highly effective, long-lasting therapy. The National Medical Advisory Committee of the National Multiple Sclerosis Society has reviewed recent literature on AHSCT for the purpose of making recommendations about its use based on current knowledge, as well as pointing out areas of controversy and issues requiring further research.
Observations
Studies on AHSCT have repeatedly demonstrated high efficacy and a durable outcome in people with relapsing multiple sclerosis. Recent studies have shown considerable improvement in the safety of the procedure, with much lower mortality rates than were reported earlier. Consensus is emerging about the characteristics of the best candidates for the procedure. Questions remain about the ideal protocol, particularly about the best conditioning regimen to be used to kill immune cells. Larger randomized clinical trials are needed to address the question of whether AHSCT has advantages over the most efficacious disease-modifying agents currently available. One such trial (Best Available Therapy Versus Autologous Hematopoietic Stem Cell Transplant for Multiple Sclerosis [BEAT-MS) is currently in progress.
Conclusions and Relevance
The National Multiple Sclerosis Society believes that AHSCT may be a useful treatment option for people with relapsing multiple sclerosis who demonstrate substantial breakthrough disease activity (ie, new inflammatory central nervous system lesions and/or clinical relapses) despite treatment with high-efficacy disease-modifying therapy or have contraindications to high-efficacy disease-modifying therapies. The best candidates are likely people younger than 50 years with shorter durations of disease (<10 years). The procedure should only be performed at centers with substantial experience and expertise. Ideally, recipients of the procedure should be entered into a single database, and further research is needed to establish ideal cell mobilization and immune-conditioning regimens.