Abstract Number: PB0864
Meeting: ISTH 2020 Congress
Background: Emicizumab, a bispecific monoclonal antibody replacing the function of missing activated factor VIII, has been approved as prophylaxis for patients with haemophilia A and FVIII inhibitors. However, this molecule has a strong interference effect on assays based on the activated partial thromboplastin time, such as one‐stage assays for FVIII, complicating the treatment monitoring.
Aims: The authors report the case of a 47 years-old patient with severe hemophilia A and FVIII inhibitor, who benefited from a switch toward emicizumab. Clinical tolerability was immediately very good. Biological tests were assessed after treatment initiation, especially thromboelastography (TEG®, Haemonetics), and thrombin generation assay (TGA).
Methods: The TEG® assay, made with the CRT reagent (activating simultaneously the intrinsic and extrinsic coagulation pathways) showed a normal coagulation profile. Regarding TGA, initiated with tissue factor, the peak was decreased compared to a healthy population (118 nM/min; normal values 200 – 416) and was more than 50% lower compared to the level measured before the switch and during immune tolerance induction (253 nM/min).
Results: Two months after emicizumab initiation, a replacement of his knee arthroplasty was indicated. A perioperative substitution with eptacog alpha and tranexamic acid was applied. Immediate follow-up showed a hematoma, requiring an arthroscopic knee washout with intensification in eptacog alpha injections. Biological monitoring, with TEG® and TGA, was also performed throughout the perioperative period. While TEG® parameters remained very similar to the values observed before the surgery, the lag time of TGA was shortened according to the dose of eptacog alpha.
Conclusions: TGA seems to be a relevant assay to evaluate the effect of eptacog alpha druing a surgery under emicizumab. Although TGA is not a test appropriate to urgent situations, its integration in the monitoring tests for a surgery under emicizumab seems to be interesting, but needs to be evaluated on a larger population of patients.
To cite this abstract in AMA style:Sattler L, Gerout A-, Feugeas O, Herb A, Grunebaum L, Desprez D. Use of Thromboelastography and Thrombin Generation Assay in a Patient Treated with Emicizumab [abstract]. Res Pract Thromb Haemost. 2020; 4 (Suppl 1). https://abstracts.isth.org/abstract/use-of-thromboelastography-and-thrombin-generation-assay-in-a-patient-treated-with-emicizumab/. Accessed September 29, 2023.
« Back to ISTH 2020 Congress
ISTH Congress Abstracts - https://abstracts.isth.org/abstract/use-of-thromboelastography-and-thrombin-generation-assay-in-a-patient-treated-with-emicizumab/