Safety evaluation of emicizumab prophylaxis in individuals with haemophilia A

Expert Opin Drug Saf. 2021 Apr;20(4):387-396. doi: 10.1080/14740338.2021.1893303. Epub 2021 Feb 27.


Introduction: Emicizumab is a bispecific-humanized monoclonal antibody that improves hemostasis by bridging activated factor IX and factor X to substitute for the function of missing activated FVIII. It is an alternative to prophylaxis with factor VIII replacement and is associated with improved outcomes in individuals with hemophilia A with and without inhibitors.

Areas covered: Emicizumab is efficacious in reducing bleeding events when compared to on-demand treatment and factor-based prophylaxis. Except for the few thrombotic microangiopathy and thrombotic event cases mainly seen in the HAVEN 1 trial, emicizumab has an overall excellent safety profile with minimal side effects.

Expert opinion: Knowledge gaps include the efficacy and safety of emicizumab in younger age groups and those with mild or moderate hemophilia A. Future directions for research include exploring the risk of inhibitor recurrence in patients with a history of high titer inhibitor who have been successfully tolerized, who switch from factor prophylaxis to emicizumab, as well as conducting 'real world studies' to evaluate the patient's perception of emicizumab in regard to ease and tolerability in order to optimize individualized treatment plans.

Keywords: Emicizumab; factor; hemophilia A; monoclonal antibody; prophylaxis.

Publication types

  • Review

MeSH terms

  • Antibodies, Bispecific / administration & dosage
  • Antibodies, Bispecific / adverse effects*
  • Antibodies, Monoclonal, Humanized / administration & dosage
  • Antibodies, Monoclonal, Humanized / adverse effects*
  • Factor VIII / administration & dosage
  • Hemophilia A / drug therapy*
  • Hemorrhage / etiology
  • Hemorrhage / prevention & control
  • Humans
  • Thrombosis / chemically induced


  • Antibodies, Bispecific
  • Antibodies, Monoclonal, Humanized
  • emicizumab
  • Factor VIII