Personalized Prophylaxis – Is this a Cost Efficient Approach in Haemophilia Care?

Introduction: Prophylaxis is standard of care in severe haemophilia of children and adolescents, its impact on health and quality of life, being demonstrated also in adults. As the replacement factors are representing about 90% of all costs, the individualization of therapy could be of utmost importance.

Objectives: As prophylaxis has been only recently introduced in our country, we are looking for the most cost-efficient regimen of therapy. In our present descriptive, non-interventional study we are aiming at evaluating the economic impact of a personalized, pharmacokinetic driven short term prophylaxis.

Patients and Methods: The study was conducted on 37 consecutive patients with severe haemophilia A, without inhibitors, and with chronic arthropathy (81% of them with target joints). We used a dosage of 36.7+-5.3 IU/kgbw recombinant factor VIII aiming a range of 1-5 IU FVIII/dl; the level of FVIII was checked with one stage coagulometric assay pre and 48 hours post-injection. In vivo recovery, controlled at 48 hours’ post-administration, was compared with the estimated values calculated based on conditional probabilities by means of Bayesian statistics.

Results and discussion: In accordance to the Delphi consensus the dosage we used gave an estimated FVIII level between 1-5 IU/dl in 67.6% and between 5-10 IU/dl in 32.4% of cases. The inter-individual variability of same dosage in our real life was astonishing. The activity levels fitted into these groups only in 48.7% and 21.6% respectively; in 5.4% and 24.3% the levels were under 1IU/dl and above 10IU/dl, respectively. That discordance between real and estimated levels of FVIII recovery (7.4 vs 4.7 IU/dl, p =  0.025) had a certain global financial impact: a usage of about 2662.2 IU/kg/patient, in comparison with 1689.2 IU/kg/patient sufficient for an incremental recovery of 1-5 IU; the difference of 973 IU/patient/administration is equivalent in monetary values with about 418.4 euro/patient/administration.

Conclusions: Despite of the numerous barriers to the implementation of pharmacokinetic study (type of used product, Bayesian forecast calculation, blood sampling), a population pharmacokinetic can be an important tool for a cost-efficient therapeutical approach of persons with hemophilia.