Primary prophylaxis for children with severe congenital factor VII deficiency - Clinical and laboratory assessment

Blood Cells Mol Dis. 2017 Sep:67:86-90. doi: 10.1016/j.bcmd.2016.12.008. Epub 2016 Dec 19.

Abstract

Severe congenital factor VII (FVII) deficiency is a rare bleeding disorder. Prophylaxis with replacement therapy has been suggested to patients, yet the most beneficial dosing regimens and therapy intervals are still to be defined. Due to the lack of evidence-based data, we hereby present our experience with long-term administration and monitoring primary prophylaxis in children with severe FVII deficiency and an extremely high bleeding risk. Four children with familial FVII deficiency, treated by prophylactic recombinant activated factor VII (rFVIIa), 15-30μg/kg/dose, given 2-3 times weekly since infancy, are discussed. Clinical follow up and monitoring laboratory assays, including thrombin generation, measured at various time points after prophylactic rFVIIa administration are presented. Among our treated patients neither FVII activity nor thrombin generation parameters (both already declined 24h post rFVIIa administration) were able to predict the impact of prophylaxis, and could not be used as surrogate markers in order to assess the most beneficial treatment frequency. However, the long clinical follow-up and comprehensive laboratory assessment performed, have shown that early primary prophylaxis as administered in our cohort was safe and effective.

Keywords: FVII deficiency; Prophylaxis; Recombinant activated factor VII (rFVIIa); Thrombin generation.

MeSH terms

  • Child
  • Child, Preschool
  • Factor VII Deficiency / blood
  • Factor VII Deficiency / complications
  • Factor VII Deficiency / metabolism
  • Factor VII Deficiency / prevention & control*
  • Factor VIIa / administration & dosage
  • Factor VIIa / therapeutic use*
  • Female
  • Hemorrhage / blood
  • Hemorrhage / etiology
  • Hemorrhage / metabolism
  • Hemorrhage / prevention & control
  • Humans
  • Male
  • Recombinant Proteins / administration & dosage
  • Recombinant Proteins / therapeutic use
  • Thrombin / metabolism

Substances

  • Recombinant Proteins
  • recombinant FVIIa
  • Factor VIIa
  • Thrombin