Predicting the outcomes of using longer-acting prophylactic factor VIII to treat people with severe hemophilia A: a hypothetical decision analysis

Long-Term Outcomes of Previously Treated Adult and Adolescent Patients with Severe Hemophilia A Receiving Prophylaxis with Extended Half-Life FVIII Treatments: An Economic Analysis from a United Kingdom Perspective

Background

The standard of care for patients with hemophilia A is prophylaxis with factor VIII (FVIII) therapies. Extended half-life (EHL) FVIII products offer a reduced infusion burden compared with standard FVIII treatments. However, comparative evidence between EHLs is lacking.

Objective

To develop a pharmacodynamic–pharmacokinetic decision model to predict comparative bleed outcomes of adolescents and adults with hemophilia A receiving treatment with various EHL FVIII therapies, capturing differences in cumulative bleeding episodes, breakthrough bleed resolution and resource costs, as well as quality-adjusted life years (QALYs).

Methods

The patient population from the pathfinder 2 Phase III clinical trial was used to understand the link between FVIII levels and annual bleeding rates (ABRs). Pharmacokinetic/pharmacodynamic modeling was subsequently applied to estimate FVIII levels for four EHL FVIII treatments (turoctocog alfa pegol [Esperoct^®], rurioctocog alfa pegol [Adynovi^®], efmoroctocog alfa [Elocta^®], and damoctocog alfa pegol [Jivi^®]) to predict comparative ABRs. FVIII consumption costs (due to prophylactic treatment and breakthrough bleed resolution) and resource costs, as well as QALYs, were subsequently estimated from a UK NHS perspective over a 70-year time horizon.

Results

Turoctocog alfa pegol prophylaxis resulted in 8–19% fewer cumulative bleeding episodes versus comparators in the base case scenario. Assuming parity in annual prophylaxis costs, turoctocog alfa pegol prophylaxis reduced the cost of product and resource use to resolve a breakthrough bleed by 9–25% versus comparators. Prophylaxis with turoctocog alfa pegol was also associated with the most QALYs, representing a discounted QALY gain of 0.35–1.05 compared with the other treatments.

Conclusion

Using a pharmacodynamic–pharmacokinetic decision model, turoctocog alfa pegol prophylaxis was associated with fewer cumulative bleeds, as well as lower product and resource costs related to resolving a breakthrough bleed and most QALYs versus comparators.