Alemtuzumab (LEMTRADA) and multiple sclerosis. Biased evaluation, evidence of serious risks.

As of late 2014, interferon beta injection was the standard "disease-modifying" treatment for patients with relapsing-remitting multiple sclerosis, in the absence of a better alternative. Alemtuzumab (Lemtrada degree, Genzyme Therapeutics), an antilymphocyte monoclonal antibody first used in some types of leukaemia, is authorised in the European Union, at a different dosage, for patients with multiple sclerosis. Clinical evaluation in multiple sclerosis is based on three unblinded trials comparing alemtuzumab with interferon beta-1a. These trials were all biased in favour of alemtuzumab and thus fail to establish the potential value of this immunosuppressant. Overall, adverse effects, including the most severe, were more frequent with alemtuzumab than with interferon beta-1a. The adverse effects of alemtuzumab reported in these trials had already been observed in cancer patients. They included potentially severe reactions to the infusion, as well as a risk of infections and cancer due to profound and prolonged immunosuppression. At the dosage authorised in multiple sclerosis, autoimmune disorders such as thyroid disorders and immune thrombocytopenic purpura are particularly frequent and serious. In practice, patients with multiple sclerosis already have difficulty coping with the troublesome consequences of their underlying disease. They should not be subjected to the serious adverse effects of alemtuzumab, especially given the absence of any proven benefit.