Semin Thromb Hemost 2023; 49(06): 651-660
DOI: 10.1055/s-0043-1768660
Review Article

The Use of Bypassing Treatment Strategies in Hemophilia and Their Effect on Laboratory Testing

Rajiv K. Pruthi
1   Division of Hematology, Department of Internal Medicine, Comprehensive Hemophilia Center, Rochester, Minnesota
2   Division of Hematopathology, Department of Laboratory Medicine and Pathology, Special Coagulation Laboratory, Mayo Clinic, Rochester, Minnesota
Dong Chen
2   Division of Hematopathology, Department of Laboratory Medicine and Pathology, Special Coagulation Laboratory, Mayo Clinic, Rochester, Minnesota
› Author Affiliations


Factor VIII and IX inhibitors in congenital hemophilia A and B, respectively, neutralize the infused coagulation factor concentrate rendering them ineffective. Bypassing agents (BPAs) that circumvent the block imposed by the inhibitors are used for the prevention and management of bleeding. Activated prothrombin complex concentrate was the original BPA, recombinant activated factor VII was then introduced, and more recently nonfactor agents that target the procoagulant and anticoagulant systems have been developed and are in clinical use (e.g., emicizumab, a bispecific antibody for hemophilia A). Other BPAs are in clinical trials (e.g., fitusiran targets antithrombin, concizumab and marstacimab target tissue factor pathway inhibitor, and SerpinPC targets activated protein C). The BPAs have a varied effect on coagulation assays, and as more patients are exposed to these agents, it is important to be aware of the effects. Herein, we present an overview of the effect of BPAs on routine and specialized coagulation assays including thrombin generation and viscoelastic assays.

Publication History

Article published online:
05 May 2023

© 2023. Thieme. All rights reserved.

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