Emicizumab and the clinical laboratory

Abstract

Abstract This review describes and discusses the different assays used to measure the effectiveness of the novel therapeutic agent, emicizumab, as well as monitor factor VIII activity in patients with hemophilia A. Emicizumab is a humanized, asymmetric, bispecific, IgG4 monoclonal antibody designed to mimic the function of activated factor VIII. Clinical studies have demonstrated its utility in the successful treatment of hemophilia A patients with and without anti-factor VIII alloantibodies. The conventional methods currently used for monitoring management of hemophilia A will be discussed along with why they may be inappropriate for patients receiving emicizumab. Alternative methods, i.e global testing, will be presented and discussed in the context of emicizumab. With the increasing availability of treatment with emicizumab it is important the clinical laboratory understands the mechanism, interaction with conventional coagulation assays, and alternative methods for its monitoring.