Combination of FVIII and by-passing agent potentiates in vitro thrombin production in haemophilia A inhibitor plasma.
Author
Summary, in English
The by-passing agents, recombinant activated factor VII (rFVIIa) and activated prothrombin complex concentrate (APCC), are important tools in the treatment of patients with haemophilia A and high-responding inhibitory antibodies. It has been observed clinically that in some patients undergoing immune tolerance induction the bleeding frequency decreases, hypothetically caused by a transient haemostatic effect of infused FVIII not measurable ex vivo. We evaluated how by-passing agents and factor VIII (FVIII) affect thrombin generation (TG) in vitro using plasma from 11 patients with severe haemophilia A and high titre inhibitors. Samples were spiked with combinations of APCC, rFVIIa and five different FVIII products. Combination of APCC and FVIII showed a synergistic effect in eliciting TG (P < 0·005) for four FVIII products. When rFVIIa and FVIII were combined the interaction between the preparations was found to be additive. APCC and rFVIIa were then combined without FVIII, resulting in an additive effect on thrombin production. Each product separately increased TG above baseline. In conclusion, the amount of thrombin formed in vitro by adding a by-passing agent, was higher in the presence of FVIII. Our findings support the use of FVIII in by-passing therapy to optimize the haemostatic effect.
Department/s
Publishing year
2010
Language
English
Pages
381-386
Publication/Series
British Journal of Haematology
Volume
151
Issue
4
Links
Document type
Journal article
Publisher
Wiley-Blackwell
Topic
- Hematology
Status
Published
Research group
- Clinical Coagulation, Malmö
ISBN/ISSN/Other
- ISSN: 0007-1048