A 5-Year Single-center Experience on the Use of Emicizumab Prophylaxis in Children With Severe Hemophilia A With and Without Factor VIII Inhibitors

Objective:Emicizumab promotes efficacious hemostasis in persons with hemophilia A persons with hemophilia A with and without inhibitors. Primary analyses of real-world data and clinical trials have shown emicizumab efficacy and safety; however, long-term data are limited.Methods:This retrospective study was conducted to assess real-world long-term outcomes of pediatric patients on emicizumab in our hemophilia center between the period of February 2018 and September 2023. Relevant demographic and clinical data were gathered.Results:Seventy-eight patients were enrolled. Previously untreated patients and minimally treated patients accounted for 14.1% and 10.3% of our recruited patients, respectively. One of 5 patients with active inhibitors experienced a single recombinant activated factor VII-treated bleeding episode while on emicizumab prophylaxis. Twenty-eight (28/78) patients underwent surgical/dental procedures without bleeding complications except for 2 patients (7.1%). Thirty-three patients experienced 62 factor-treated bleeding episodes with only 11 imaging-confirmed joint/muscle bleeding episodes among 8 patients. No major safety concerns were reported in the study and emicizumab was discontinued in 5 patients (2 for antidrug antibody development, 2 for joint bleeding, and 1 for non-compliance).Conclusion:Emicizumab prophylaxis was well tolerated with no new safety concerns, and 45 patients (57.7%) of our cohort exhibited zero-treated bleeds, which was comparable to other published experiences.