Adverse events with fatal outcome associated with alemtuzumab treatment in multiple sclerosis

Sporadic fatal adverse events have been reported during treatment of multiple sclerosis with alemtuzumab. To provide a systematic overview, we searched the centralized European Medicines Agency database of suspected adverse reactions related to medicinal products (EudraVigilance) for fatal adverse events associated with treatment with alemtuzumab (Lemtrada®) for multiple sclerosis. Four independent reviewers with expertise on MS, clinical immunology, infectious diseases and clinical pharmacology reviewed the reports, and scored the likelihood for causality.

We identified nine cases with a probable and one case with a possible causal relationship between alemtuzumab treatment and a fatal adverse event. Six of these patients died within one month after treatment; one from intracerebral hemorrhage, two from acute multiple organ failure and septic shock, one from listeriosis, one from pneumonia and one from agranulocytosis. Four patients died several months after administration of alemtuzumab from either autoimmune hepatitis, immune-mediated thrombocytopenia, autoimmune hemolytic anemia or agranulocytosis. Four of the 10 cases had been published previously in case reports or congress abstracts. Fatal adverse events related to treatment with alemtuzumab occur more frequently than previously published in the literature. A significant proportion occurs in the first month after treatment.