On the second day of the European Committee for Treatment and Research in Multiple Sclerosis (ECTRIMS) 2016 Congress Sept. 14-17 in London, researchers shared their views on bone marrow transplants for relapsing forms of multiple sclerosis (MS).
The debate, “Bone marrow transplantation is a justifiable treatment for active relapsing multiple sclerosis,” showed that the disagreement is not really about whether the procedure is effective, but instead whether it is a reasonable option considering the wealth of new potent disease-modifying drugs already or soon to be available on the market.
Both researchers, representing different sides of the argument, agreed that large clinical trials comparing the effectiveness of the treatment to other approaches are needed to settle the issue.
Giovanni Mancardi from the University of Genoa in Italy argued for the use of bone marrow transplants, also known as hematopoietic stem cell transplantations. This type of treatment should be used in patients in early stages of the disease who have disease activity despite treatment, according to Mancardi.
He believes that the failure of early transplant studies was in part based on the fact that it included patients who had disabilities that were too advanced.
A problem with autologous bone marrow transplants, where the patient’s own cells are transplanted, is that the pre-treatment where the immune system is weakened or wiped out through chemotherapy is potentially life-threatening.
Newer approaches, using less harsh pre-treatments (known as conditioning regimens to doctors), have reduced side effects, and in a study published last year, Mancardi showed that a medium-intensity pre-treatment was superior to the chemotherapy drug Novantrone (mitoxantrone) in reducing MS activity.
He also cited a study showing that five years after transplants, the proportion of MS patients who had aggressive disease but remained in remission was far higher than that achieved with current drugs.
Mancardi also mentioned a study, published earlier this year, that could prolong remission even further with high-intensity pre-treatments, but he acknowledged that the risk of death following these procedures remains. But according to him, this risk has been reduced to 1 to 2 percent in recent years.
Jeffrey Cohen from the Cleveland Clinic in Ohio did not share the view that autologous bone marrow transplants should be an obvious option to patients with high disease activity. According to Cohen, there are plenty of potent medications allowing both clinicians and patients to choose treatments with differing potency, tolerability, safety, and ease of use. Also, several new treatments will soon appear on the market.
Cohen agreed that there is plenty of evidence supporting the effectiveness of bone marrow transplants. However, he maintained that studies so far have suffered several important limitations.
Many of the early studies were small and performed at a single center, and even though larger studies have been published lately, they have not included control groups, or were not compared to relevant medications. He admitted that improved pre-treatments have reduced side effects and the risk of death.
But in Cohen’s view, the question is not whether a bone marrow transplant is an option for an MS patient with aggressive disease, but whether it is a reasonable option or if it should be considered as a last resort of treatment.
Future trials, comparing bone marrow transplants with relevant drugs, will likely answer the question.