Hi Stan, August 2013
The goal of treatment with disease modifying agents in MS is evolving. More and more we are aiming to put patients into a disease activity free state. In other words, we are trying to maximize the probability that a patient will not have relapses, will not have progression of disability and will not have new lesions on their MRI. This would be the disease free state. If they have not achieved that on a first line therapy then they should be considering the newer agents such as tysabri and gilenya. To make the decision as to which to consider, they should be tested for antibodies to the JC virus that causes PML. If they don’t have antibodies to this virus then tysabri has the best risk/benefit ratio and should be considered. However, if they have failed tysabri or do have antibodies to the JC virus, then gilenya would be the appropriate choice. The challenge with gilenya is that the the full safety profile is still somewhat uncertain. So patients treated with this medication need to be followed closely and need to understand that our assessment of risk of this agent may change as we get more experience with the agent. But gilenya is approved as a first line agent and, in general, the large majority of patients do quite well on the drug.
In our experience, a few patients have had troubling diarrhea on the drug and few felt they had more MS fatigue on gilenya then they had on tysabri. But over 90% of our patients have told me they feel well on the medication and are doing well. There is a modest suppression of the immune system which does manifest as a small increased risk of infection and this is another reason patients need to be followed closely. But in reality I have not had more trouble with gilenya than I have had with interferons. The major remaining questions relate to if the drug has a risk of life threatening infection, cardiac or cancer, particularly skin cancer. If present they would obviously be relatively rare. But we don’t currently have enough data either way to rule in or out these possibilities which is the purpose of ongoing safety studies. But this is a problem for many widely used drugs. Gilenya is often considered a second line drug in practice but that is mostly due to the fact many insurance companies require patients to have failed the other agents because of its cost.
I hope this helps.
Timothy Vollmer, MD, FAAN
Professor of Neurology
Medical Director-Rocky Mountain MS Center
Co-Director-Rocky Mountain MS Clinic Anschutz Medical Center
University of Colorado Denver