Outcomes of Emicizumab in Acquired Hemophilia Patients: A Systematic Review

Emicizumab, a bispecific factor VIII mimetic antibody, was approved in 2018 for bleeding prophylaxis in congenital hemophilia A with or without inhibitors. Since then, several case reports and case series have described the off-label use of emicizumab in acquired hemophilia A (AHA), and data from two clinical trials were recently published (AGEHA, GTH-AHA-EMI). To describe the reported data on the outcomes of emicizumab, highlighting its benefit/risk profile in treatment. We conducted a literature search in PubMed, Scopus, Cochrane, and Google Scholar up to August 2024, including all scientific articles reporting clinical outcomes of emicizumab use in patients with AHA. Thirty-two studies were included in the final review, covering a total of 171 AHA patients. The majority started emicizumab for active bleeding management and prophylaxis with various regimens. Follow-up duration and remission criteria varied. Two clinical trials supported the use of emicizumab for bleeding prophylaxis with a new dosing regimen and completion criteria. Bleeding was well managed in all cases, with no major recurrent bleeds. Some adverse events were reported : 3 cases of deep venous thrombosis, 2 cases of stroke, and 2 cases of anti-emicizumab drug antibodies developing in patients with thromboembolic risk factors. Based on published data, emicizumab appears to be effective in bleeding management and prophylaxis in AHA patients, with a favorable benefit/risk profile.