Emicizumab is a humanized immunoglobulin (Ig) G4-kappa monoclonal antibody that mimics the function of the coagulation Factor VIII. It has the capacity to bind simultaneously to activated Factor IX (Factor IXa) and Factor X. Emicizumab brings Factor IX and Factor X together and thereafter enhance the catalytic activity of Factor IXa that allows it to activate the coagulation cascade that will subsequently lead to the segmentation of fibrinogen into fibrin and the formation of blood clots. The effect of Emicizumab is translated into the restoration of the blood coagulation process and, therefore, in the reduction of hemorrhagic episodes.