Opinion
Video
Author(s):
Bruce Cree, MD, PhD, MAS, discusses how sphinogine-1-phospate (S1P) receptor modulators may suppress a patients immune system and key considerations clinicians should make in light of this.
Transcript
Bruce Cree, MD, PhD, MAS: One of the things that the patients want to know about is whether medications they’re taking are suppressing their immune system, and what will be the long-term consequences from use of their MS disease-modifying therapies. It is not surprising that this is a considerable concern for our patients who have a chronic illness that requires long-term treatment. So it’s very important to understand this across the board, regardless of the disease-modifying therapy that any individual is using. The S1P [sphingosine-1-phosphate] receptor modulators, as a class, have excellent data supporting their long-term safe use in multiple sclerosis. Although these medications can have immune-suppressive effects, as proven by the rare occurrence of opportunistic infections associated with these medications—especially the most serious one, progressive multifocal leukoencephalopathy, or PML—in general, the vast majority of patients are not profoundly immune-suppressed from taking these medications. Several studies have looked at the effect of these medications on lymphocyte subsets and on other cells of the immune system, and, of course, not surprisingly, since these medications cause sequestration of lymphocytes within the lymph nodes and spleen, you see a decrease in cells in the circulation of several different lymphocyte subsets in circulation, and that is to be expected as part of the mechanism of action of all of these products. We also see some effects in terms of monocytes and neutrophils as well, which is unexpected because these cells don’t have S1P receptors on them, so it must have to do with networks within the immune system and crosstalk between the adaptive immune system and the innate immune system. Those details remain to be worked out.
Transcript edited for clarity.