Abstract Number: OC 45.4
Meeting: ISTH 2021 Congress
Background: Hemophila A patients treated with replacement products are routinely monitored for Factor VIII (FVIII) activity using either one-stage clotting assays (OSA) or chromogenic assays (CA). It is well known that laboratory assay results for extended half-life FVIII products can be affected by the assay and reagent type.
Aims: The purpose of this study was to investigate the recovery of BAY 94-9027 (damoctocog alfa pegol; Jivi®) in OSA and CA using different reagents.
Methods: A sample set composed of plasma samples spiked with 5 different BAY 94-9027 levels, ranging from 0.05 – 1.5 IU/mL were distributed to 155 laboratories in 13 different countries for measurement with their local FVIII assays. Currently 97 laboratories returned results. For each of the samples, the relative recovery to the target value was calculated. A recovery between 70% and 130% was considered to be acceptable.
Results: Table 1 and 2 show the median recovery over the entire concentration range for the different APTT reagents and chromogenic assays, respectively.
| APTT reagent |
Type of reagent |
N |
Median Recovery (range) (%) |
| APTT-SP | Silica | 2 | 52 (49 – 90) |
| SynthasIL | Silica | 38 | 98 (79 – 110) |
| Pathromtin SL | Silica | 11 | 98 (75 – 119) |
| PTT-A | Silica | 5 | 6 (5 – 7) |
| Actin FS | Ellagic Acid | 8 | 127 (113 – 156) |
| Actin FSL | Ellagic Acid | 4 | 99 (79 – 141) |
| SynthaFax | Ellagic Acid | 2 | 116 (114 – 137) |
| CK Prest | Cephalin/Kaolin | 17 | 121 (98 – 125) |
| Cephscreen | Cephalin/Polyphenolic Activator | 2 | 112 (93 – 129) |
The median Recovery of the BAY 94-9027 Spiked Samples for the Different One-Stage Assays in the Study
| Assay |
Type of reagent |
N |
Median Recovery (range) (%) |
| Biophen | Human | 12 | 103 (88 – 116) |
| Chromogenix | Bovine | 15 | 101 (70 – 124) |
| Elektrachrome | Bovine | 2 | 96 (71 – 125) |
| Precision Biologics | Human / Bovine | 1 | 75 (58 – 95) |
| Siemens | Bovine | 7 | 80 (56 – 100) |
| Trinichrom | Bovine | 6 | 59 (54 – 73) |
The Median Recovery of the BAY 94-9027 Spiked Samples for the Different Chromogenic Assays in the Study
Most of the APTT reagents showed an acceptable median recovery between 76% and 127%. Only APTT-SP and PTT-A showed significant underestimation, while Actin FS showed slight overestimation.
For the two most frequently used CA methods (Biophen, Chromogenix) the median recovery was around 100%. For the Siemens method, the recovery decreased from 100% to 56% as the Bay 94-9027 concentration decreased, while the Trinichrom method showed a decreased recovery over the full range of BAY 94-9027 concentrations.
Conclusions: With most of the APTT reagents included in this study (except APTT-SP and PTT-A) BAY 94-9027 can be reliably measured in a OSA over a wide concentration range. BAY 94-9027 can also be reliably measured with the Biophen and Chromogenix CA methods, while a systematic underestimation was observed with the Trinichrom method. The Siemens chromogenic method demonstrates a concentration-dependent decline in recovery.
To cite this abstract in AMA style:
Meijer P, Adcock D, M Hollestelle , Marlar R. Recovery of BAY 94-9027 [Jivi®] with One-stage Clotting and Chromogenic Assays: A Multicentre Study [abstract]. Res Pract Thromb Haemost. 2021; 5 (Suppl 1). https://abstracts.isth.org/abstract/recovery-of-bay-94-9027-jivi-with-one-stage-clotting-and-chromogenic-assays-a-multicentre-study/. Accessed September 24, 2021.« Back to ISTH 2021 Congress
ISTH Congress Abstracts - https://abstracts.isth.org/abstract/recovery-of-bay-94-9027-jivi-with-one-stage-clotting-and-chromogenic-assays-a-multicentre-study/