Octocog alfa(Bayer AG)

Clotting factor concentrates have been the mainstay of severe hemophilia treatment over the last 50 years. Differences in risk of neutralizing antibody (inhibitor) formation according to concentrate used remain clinically relevant.

To assess inhibitor development according to type of clotting factor concentrate in previously untreated patients (PUPs) with severe hemophilia A and B.

The European Haemophilia Safety Surveillance (EUHASS) and Canadian Bleeding Disorders Registry (CBDR) have been monitoring adverse events overall and according to concentrate for 11 and 8 years, respectively. Inhibitors were reported quarterly, and PUPs completed 50 exposure days without inhibitor development annually. Cumulative inhibitor incidences and 95% confidence intervals (CIs) were compared without adjustment for other risk factors.

Fifty-six European and 23 Canadian centers reported inhibitor development in 312 of 1219 (26%; CI, 23%-28%) PUPs with severe hemophilia A and 14 of 173 (8%; CI, 5%-13%) PUPs with severe hemophilia B. Inhibitor development was lower on plasma-derived factor (F)VIII (pdFVIII, 20%; CI, 14%-26%) than on standard half-life recombinant FVIII (SHL-rFVIII, 27%; CI, 24%-30% and odds ratio, 0.67; CI, 0.45%-0.98%; P = .04). Extended half-life recombinant FVIII (EHL-rFVIII, 22%; CI, 12%-36%) showed an intermediate inhibitor rate, while inhibitor rates for Advate (26%; CI, 22%-31%) and Kogenate/Helixate (30%; CI, 24%-36%) overlapped. For other SHL-rFVIII concentrates, inhibitor rates varied from 3% to 43%. Inhibitor development was similar for pdFIX (11%; CI, 3%-25%), SHL-rFIX (8%; CI, 3%-15%), and EHL-rFIX (7%; CI, 1%-22%).

While confirming expected rates of inhibitors in PUPs, inhibitor development was lower in pdFVIII than in SHL-rFVIII. Preliminary data suggest variation in inhibitor development among different SHL-rFVIII and EHL-rFVIII concentrates.

Introduction: rVIII-SingleChain, a recombinant factor VIII (rFVIII), has demonstrated safety and efficacy in patients with hemophilia A in clinical trials and real-world evidence. This analysis aimed to estimate the potential budget impact of increasing the usage of rVIII-SingleChain for the prophylactic treatment of hemophilia A over 3 years in Italy.Methods: Patients with moderate and severe hemophilia A receiving prophylaxis were included in the analysis. Epidemiological data were obtained from published literature. Mean product consumption and mean annual bleeding rate for rVIII-SingleChain, rFVIIIFc, octocog alfa and BAY 81-8973 were based on pooled real-world data from Italy, Germany and US. A budget impact model has been developed in order to compare two scenarios: a base-case scenario where current rVIII-SingleChain shares are kept constant over 3 years and an alternative scenario where rVIII-SingleChain shares increase by taking from other rFVIII products. Analysis 1 was based on the current Italian list prices and Analysis 2 considered current regional acquisition prices for both scenarios.Results: Annually, adult patients treated with rVIII-SingleChain prophylaxis are expected to consume 324,589 units per patient, resulting in annual costs of €240,196 per patient. In Analysis 1, comparing the base case (constant market share of 9% rVIII-SingleChain over time) with the alternative scenario (higher rVIII-SingleChain market share and increasing from 15% in the first year to 25% in the third year), the total expenditure for prophylaxis using rFVIII products is expected to decrease by €1.4 million in Year 1, by €3.1 million in Year 2 and by €5.4 million in Year 3. In Analysis 2 based on regional prices, the results remained consistent.Discussion/Conclusion: This analysis suggests that increasing utilization of rVIII-SingleChain in hemophilia A patients may lead to cost savings as a result of reduced consumption with uncompromised efficacy in bleed protection.