title: Preclinical toxicity biomarkers for combination treatment with clotting factors rFXIII and rFVIIa.
abstract: Combination treatment with the clotting factors recombinant activated factor VII (rFVIIa), serine protease, and recombinant factor XIII (rFXIII), protransglutaminase, is being explored for haemostatic therapy. We performed a single-dose toxicology study in the cynomolgus monkey, with four dose groups receiving 0.1 + 0.34 mg kg(-1) (group 1), 0.33 + 1.12 mg kg(-1) (group 2), 1.67 + 5.60 mg kg(-1) (group 3) and 5.00 + 16.80 mg kg(-1) (group 4) of a rFVIIa + rFXIII combination. In the three lower dose groups, no clinical, histopathological or blood chemistry changes were observed. In group 4, the animals died at 4 h post-dosing, with histopathology revealing a systemic coagulopathy resembling, but distinct from, disseminated intravascular coagulation. Due to the absence of toxicity warning signs, toxicity biomarkers were identified by a Western blot-based screening of approximately 20 plasma proteins known to be involved in the clotting cascade. Three of the examined proteins were specifically affected by rFVIIa + rFXIII treatment. Fibronectin and fibrinogen exhibited dose-dependent reductions from less than 10% reduction (group 2) to more than 90% reduction (group 4). These reductions were reversible, and specific. For vitronectin, a dose-dependent conversion to the 65-kDa form was found to occur in groups 3 and 4. Thus, fibrinogen, fibronectin and vitronectin represent the first biomarkers for clotting factor toxicity.
authors.affiliation: Novo Nordisk A/S, Maalov, Denmark. mboz@novonordisk.com
authors.forename: M B
authors.initials: MB
authors.lastname: Oleksiewicz
authors.forename: R
authors.initials: R
authors.lastname: Schaal-Jensen
authors.forename: B
authors.initials: B
authors.lastname: Kiehr
authors.forename: J Steenbuch
authors.initials: JS
authors.lastname: Krabbe
authors.forename: C
authors.initials: C
authors.lastname: Sommer
mesh_terms: D000818:Animals; D015415:Biomarkers / Q000097:blood*; D015153:Blotting, Western; D004353:Drug Evaluation, Preclinical; D015942:Factor VIIa / Q000633:toxicity*; D005176:Factor XIII / Q000633:toxicity*; D005340:Fibrinogen / Q000032:analysis*; D005353:Fibronectins / Q000097:blood*; D006489:Hemostatic Techniques / Q000009:adverse effects; D006801:Humans; D008252:Macaca fascicularis; D011994:Recombinant Proteins / Q000633:toxicity; D019096:Vitronectin / Q000097:blood*
chemical_list: D015415:Biomarkers; D005353:Fibronectins; D011994:Recombinant Proteins; D019096:Vitronectin; D005340:Fibrinogen; D005176:Factor XIII; D015942:Factor VIIa