On 2014 May 15, Andrea Messori commented:

Half-life of Factor VIII in patients with haemophilia A: comparison between B-domain deleted recombinant Factor VIII and full-length recombinant Factor VIII.

The study by Gruppo et al. [1] has described an analysis in which the half-life of Factor VIII was compared among plasma-derived concentrates , B-domain deleted recombinant products (BDD-rFVIII), and full-length recombinant products (FL-rFVIII). While the issue of the differences between plasma-derived concentrates and recombinant products has been debated in very numerous papers, the difference in the half-life between BDD-rFVIII and FL-rFVIII is a quite original finding, particularly because the authors conducted a pooled analysis based on a specific meta-analytical model (random-effect model). In their meta-analysis, however, Gruppo et al. [1] did not present any Forest plot; furthermore, some details were missing concerning the methods (e.g. the statistical software used for the analysis) and the results (e.g. the evaluation of heterogeneity). For this reason, we have re-analyzed the half-life data reported by Gruppo et al. [1] in their Table 3 and Figure 2 for BDD-rFVIII and FL-rFVIII. Our analysis was based on the Open Meta-analyst software (Open Meta-Analyst, version 4.16.12, Tufts University, url http://tuftscaes.org/open_meta/) and included the assessment of heterogeneity. The results of our re-analysis (study-specific and meta-analytic values of half-life with Forest plot and estimates of confidence intervals and heterogeneity) are available at the following Internet link: http://www.osservatorioinnovazione.net/papers/gruppo2003-reanalysis.pdf Our estimates of half-life for BDD-rFVIII and FL-rFVIII are nearly identical to those found by Gruppo et al.[1]. As expected, our results have also confirmed that the half-life of BDD-rFVIII is significantly shorter than that of FL-rFVIII

References

1. Gruppo RA, Brown D, Wilkes MM, Navickis RJ. Comparative effectiveness of full-length and B-domain deleted factor VIII for prophylaxis--a meta-analysis. Haemophilia. 2003 May;9(3):251-60.

On 2014 May 15, Andrea Messori commented:

Half-life of Factor VIII in patients with haemophilia A: comparison between B-domain deleted recombinant Factor VIII and full-length recombinant Factor VIII.

The study by Gruppo et al. [1] has described an analysis in which the half-life of Factor VIII was compared among plasma-derived concentrates , B-domain deleted recombinant products (BDD-rFVIII), and full-length recombinant products (FL-rFVIII). While the issue of the differences between plasma-derived concentrates and recombinant products has been debated in very numerous papers, the difference in the half-life between BDD-rFVIII and FL-rFVIII is a quite original finding, particularly because the authors conducted a pooled analysis based on a specific meta-analytical model (random-effect model). In their meta-analysis, however, Gruppo et al. [1] did not present any Forest plot; furthermore, some details were missing concerning the methods (e.g. the statistical software used for the analysis) and the results (e.g. the evaluation of heterogeneity). For this reason, we have re-analyzed the half-life data reported by Gruppo et al. [1] in their Table 3 and Figure 2 for BDD-rFVIII and FL-rFVIII. Our analysis was based on the Open Meta-analyst software (Open Meta-Analyst, version 4.16.12, Tufts University, url http://tuftscaes.org/open_meta/) and included the assessment of heterogeneity. The results of our re-analysis (study-specific and meta-analytic values of half-life with Forest plot and estimates of confidence intervals and heterogeneity) are available at the following Internet link: http://www.osservatorioinnovazione.net/papers/gruppo2003-reanalysis.pdf Our estimates of half-life for BDD-rFVIII and FL-rFVIII are nearly identical to those found by Gruppo et al.[1]. As expected, our results have also confirmed that the half-life of BDD-rFVIII is significantly shorter than that of FL-rFVIII

References

1. Gruppo RA, Brown D, Wilkes MM, Navickis RJ. Comparative effectiveness of full-length and B-domain deleted factor VIII for prophylaxis--a meta-analysis. Haemophilia. 2003 May;9(3):251-60.