Hematopoietic Stem Cells for Multiple Sclerosis

The MS Center at Swedish Neuroscience Institute played a major role in a research study that recently garnered national attention. This research was published in JAMA Neurology. This research investigated the effect of high dose immunosuppressive followed by hematopoietic stem cell therapy.

This therapy consists of collecting hematopoietic stem cells from patients' blood. Patients then undergo an intense course of immunosuppressive therapy with four medications. This therapy is sufficient to eliminate most of the patient’s bone marrow including white blood cells. The hematopoietic stem cells are then given back to the patient so that their bone marrow may be reconstituted. In multiple sclerosis (MS),  the immune system attacks the brain. The hope is that with this therapy the reconstituted immune system will have less of a tendency to attack the brain and that the disease will stabilize.

This is our second study on this technique in MS. The first study investigated the effect of this treatment on patients with more advanced disease. All but one of these patients had secondary progressive or primary progressive disease. Patients who participated in this study had very aggressive disease with rapid increases in disability. The treatment seemed to help slow the disease, but not all the patients remained stable. The current study (called the HALT-MS trial) was begun to study the effects of this treatment in people with relapsing/remitting MS who had lower levels of disability.

The HALT-MS study found that 78.4% of patients remained stable 3 years after the treatment. This success was tempered by side effects which can be substantial.

There are three types of stem cell therapy. Hematopoietic involves replacing the cells that make bone marrow, including the cells of the immune system. This is the type of stem cell therapy used in this study. A second type of therapy is mesenchymal stem cells, which are cells engineered to produce chemical signals once they are given to the patient. This might include signals to rebalance the immune system or promote myelin repair. The MS Center has been involved in research on mesenchymal stem cells also. The third type of stem cell is induced pluripotent stem cells (formerly called embryonic stem cells). These cells are intended to replace damaged tissues, for example myelin in MS. Induced pluripotent stem cells have not been studied yet in MS. We anticipate studies of these will occur in the future as the technology improves.

The results from the HALT-MS study are encouraging. However, this treatment seems best directed towards patients with relapsing MS and those patients with MS that is severe enough to warrant a treatment with substantial side effects. The other limitation is whether insurance will cover the therapy (most do not) since it can be quite expensive. Further studies are planned on this treatments both at our center and many others across North America and Europe.