Years of Thyroid Monitoring Needed After MS Drug Alemtuzumab

Treatment with the multiple sclerosis (MS) drug alemtuzumab (Lemtrada, Genzyme/Sanofi) is associated with thyroid dysfunction and an increased risk of Graves disease that may have onset later than previously thought and therefore could require longer-term monitoring, according to results of one of the largest case series to date, spanning 20 years.

“Alemtuzumab is a highly effective therapy for relapsing-remitting MS, [with a] number needed to treat to benefit of five [and] number needed to treat for a serious adverse event of 148,” say Nadia Pariani, University of Cambridge Metabolic Research Laboratories, Institute of Metabolic Science, Addenbrooke’s Hospital, Cambridge, United Kingdom, and colleagues.

“However, the development of thyroid autoimmunity months or years after treatment is a frequent complication, requiring ongoing biochemical surveillance for at least 4 years after alemtuzumab therapy to detect and treat thyroid dysfunction promptly,” they note in their article published in the Journal of Clinical Endocrinology and Metabolism.