Work

A miniaturized chemiluminescent thrombin generation assay to assess the effect of APCC in persons with hemophilia A with inhibitors: an observational study

Year: 2026

Type: article

Abstract: Background Monitoring of bypassing agents in persons with hemophilia A with inhibitors (PwHAi) is complicated, especially when multiple treatment modalities are combined. The thrombin generation assay (TGA) might address these issues but is hampered by limited availability and standardization. Objectives To assess the performance of a novel microfluidic TGA (microfluidic-TGA lum ) to monitor the effect of activated prothrombin complex concentrate (aPCC) in PwHAi. Methods The microfluidic-TGA lum was used in FVIII deficient plasma samples with different concentrations of FVIII inhibitors spiked with aPCC and samples from six PwHAi before and after aPCC administration. Peak height (PH), area under the curve (AUC), velocity index (VI), and lag time were compared with results obtained using the Ceveron TGA with RB reagents (TGA Ceveron-RB ). Results Increasing concentrations of aPCC spiked in FVIII deficient plasma significantly increased PH, AUC, VI and shortened lag time in the microfluidic-TGA lum , with strong correlation with TGA Ceveron-RB outcomes (R Pearson 0.92-0.97). Microfluidic-TGA lum outcomes improved similarly after administering aPCC to PwHAi, though thrombin generation exceeded normal values, with PH reaching 174% of that observed in normal pooled plasma. In contrast, the TGA Ceveron-RB displayed persistently low thrombin generation and weak correlation with microfluidic-TGA lum (R Pearson 0.28-0.52). Exploratory follow-up experiments revealed that accumulation of prothrombin in PwHAi plasma and low phospholipid concentration in the TGA Ceveron-RB might explain this discrepancy. Conclusions The microfluidic-TGA lum detects the hemostatic effects of aPCC treatment in PwHAi. Assay-specific differences in TGA response may complicate aPCC monitoring in PwHAi. Our findings underscore the need for further mechanistic TGA studies and standardization.

Source: Research and Practice in Thrombosis and Haemostasis

DOI: 10.1016/j.rpth.2026.106920