Efficacy of emicizumab therapy in two adult patients with type 3 von Willebrand disease.

Type 3 von Willebrand disease (T3VWD) is a rare inherited bleeding disorder caused by the absence of von Willebrand factor (VWF). The traditional treatment for T3VWD has been VWF concentrates, but their effectiveness may be limited due to the development of alloantibodies. Emicizumab, a bispecific mAb, has shown promise in treating hemophilia A and is being studied as prophylaxis for T3VWD. In this case series, two patients with T3VWD received emicizumab prophylaxis and experienced a significant reduction in bleeding episodes and improved quality of life with fewer healthcare encounters. Although breakthrough bleeding was rare, one patient experienced a terminal intracranial bleed. Despite limited clinical experience with emicizumab in T3VWD, these cases suggest that emicizumab may be a valuable prophylactic option for patients with T3VWD. Further research is needed to determine the long-term efficacy and safety profile of emicizumab and optimal therapy for breakthrough bleeds in this patient population.