Approximation of emicizumab plasma levels in emergency situations. A practical approach

• DOI: 10.1111/hae.14264
• Publication Date: 2021-02-01T14:57:30Z
• Authors: Isabell Pekrul; Christian Pfrepper; Geli Calatzis; Andreas Giebl; Annelie Siegemund; Stefanie Grützner; Michael Spannagl
• Keywords: Haemophilia B

Abstract Introduction A dedicated emicizumab assay based on the modified one‐stage factor VIII (FVIII) (mOSA) is mainly available in haemophilia treatment centres (HTC). method to estimate plasma levels a widely would be desirable, especially for emergency situations. Aim level approximation (ELA) using routine FVIII activity measurement with standard (sOSA) was developed and evaluated. Method Within this pilot study, 59 samples from patients severe (n = 8) without inhibitors under were analysed sOSA following manual 1:8 sample pre‐test dilution saline. The determined two different laboratories, analyser platforms each. Results results demonstrated an excellent correlation of approximated concentration mOSA ( r > .9; p < .05). ELA showed sensitivity 93.3% specificity 89.6% predict pre‐defined cut‐off‐value ≤30 µg/ml discrimination between subtherapeutic therapeutic levels. Conclusion Approximation by discriminates might facilitate clinical decision‐making situations, such as bleeding, trauma or urgent surgery case that assays are not available.