Abstract Number: PB0303
Meeting: ISTH 2022 Congress
Theme: Platelet Disorders, von Willebrand Disease and Thrombotic Microangiopathies » ADAMTS13 and TTP
Background: The anti-von Willebrand factor (VWF) nanobody caplacizumab has found its way into current standard of care for immune-mediated thrombotic thrombocytopenic purpura (iTTP), in addition to plasma exchange (PEX), steroids and rituximab. However, real-world use of caplacizumab remains heterogenous, including alternate-day dosing of caplacizumab.
Aims: The aim of this study is to better characterize the use of an alternate-day dosing regimen for caplacizumab in iTTP patient management. In detail, we aim to identify patients at risk for exacerbations or relapses during alternate-day caplacizumab treatment, to determine the optimal timing for this treatment modification and to analyze the socioeconomic benefits of this regimen.
Methods: This study is conducted as a retrospective observational study. iTTP patients treated with an alternate-day regimen of caplacizumab were identified from a large cohort of iTTP patients treated at different medical centers in Austria and Germany since 2018.
Results: All patients were initially treated according to labeling with daily caplacizumab injections and additionally received rituximab and steroids (n=25). Median time of daily, post-PEX caplacizumab treatment until introduction of alternate-day dosing in this cohort was 11 days. Thereafter, alternate-day dosing of caplacizumab led to persisting normal platelet counts in the majority of patients in this cohort. Exacerbations and relapses occurred only in five patients, and all instances could be managed solely by intensification of caplacizumab treatment to daily dosing.
Based on the current market price (September 2021) for a single caplacizumab dose of 4396 € (7724 USD), this treatment modification led to cost savings of 1 622 124 € (2 850 156 USD) in this cohort.
Conclusion(s): Extension of caplacizumab application intervals from daily to alternate-day dosing may be safely considered in selected patients after 3 to 4 weeks of daily treatment. Earlier modifications may be discussed in low-risk patients but require close monitoring for clinical and laboratory features of thrombotic microangiopathy.
To cite this abstract in AMA style:
Kühne L, Kaufeld J, Völker L, Wendt R, Schönermarck U, Eichenauer D, Buxhofer-Ausch V, Menne J, Brinkkoetter P, Knöbl P. Alternate-day dosing of caplacizumab for immune-mediated thrombotic thrombocytopenic purpura [abstract]. https://abstracts.isth.org/abstract/alternate-day-dosing-of-caplacizumab-for-immune-mediated-thrombotic-thrombocytopenic-purpura/. Accessed March 21, 2024.« Back to ISTH 2022 Congress
ISTH Congress Abstracts - https://abstracts.isth.org/abstract/alternate-day-dosing-of-caplacizumab-for-immune-mediated-thrombotic-thrombocytopenic-purpura/