Researchers in the U.K. have evaluated additional findings about the immune-system impacts of Lemtrada® (alemtuzimab, Sanofi Genzyme), a disease-modifying therapy for treating people with relapsing MS.
The team used data from phase 3 clinical trials submitted to the European Medicines Agency during the drug’s successful approval process. Some of this data was previously reported at medical meetings and in Lemtrada’s prescribing information.
Among their findings, they report that Lemtrada caused long-term reduction of specific immune cells (memory B and T cells, including regulatory T cells). They also found that the body rapidly repopulated an overabundance of immature B cells.
They propose that the blockade of memory B and T cells drives the beneficial effects of Lemtrada.
They also speculate that the known potential side effect for autoimmune thyroid disease and other autoimmune disorders may be triggered by the overabundance of immature B cells that occurs when there are few regulatory T cells to keep them in check.
Studies like this one, which reveal more information about a therapy’s mode of action, are important and may also lead to insights about how to reduce side effects.
Drs. Klaus Schmierer, David Baker and others at the Queen Mary University of London report their findings in JAMA Neurology, published online June 12, 2017.