New Recombinant Factor IX Leads to Significant Cost Savings in Hemophilia B

Switching patients with hemophilia B to a new extended-half-life recombinant factor IX (FIX) concentrate likely cut annual treatment costs in Canada by about 10%, according to a new report.

The study found that the switch was associated with improvements in annualized bleed rates. The analysis was published in the journal Research and Practice in Thrombosis and Haemostatis.

Congenital hemophilia B is caused by an absence or dysfunction of the clotting factor FIX.

“The mainstay of treatment for severe and moderate hemophilia B is a regular prophylactic infusion of FIX clotting factor into the bloodstream to maintain sufficient FIX activity levels and thus, prevent bleeding,” said corresponding author Alfonso Iorio, MD, PhD, of McMaster University.

FIX is also used as a treatment in cases of breakthrough bleeding episodes.

The standard half-life of FIX concentrates is 18-24 hours, the authors said, and thus administration is required once or twice per week. However, extended-half-life (EHL) concentrates are also available for certain patients; these only require administration every 1 to 2 weeks.

Beginning in 2018, the agency in charge of procuring FIX concentrates for all of Canada’s provinces except Quebec switched from the EHL concentrate eftrenonacog alfa to a new EHL concentrate, nonacog beta pegol (N9-GP). Patients on eftrenonacog alfa were required to switch to the new concentrate. Patients who were taking a standard-half-life concentrate or who were taking plasma-derived FIX had the option of switching to N9-GP.

In the new study, investigators sought to understand how the switch to N9-GP might have affected hemophilia treatment costs and patient outcomes. They used real-world data from the Canadian Bleeding Disorders Registry (CBDR) to build a model comparing annual costs associated with the older concentrates and with N9-GP. When doing so, the investigators had to use estimates for the FIX concentrates, because the competitive bidding process for the products does not allow for actual prices to be made public.

“Because FIX prices are confidential in Canada, the model assumed cost parity for annual prophylaxis with each FIX based on the product monograph recommended dosing regimen to calculate an estimated price per international unit for each product,” they said.

A total of 42 patients met the study’s inclusion criteria. They had a median age of 42 years. Sixteen of those patients switched from standard-half-life concentrates to N9-GP; the remaining 26 switched from eftrenonacog alfa to N9-GP. Their real-world prophylactic and breakthrough treatment costs were used along with the price estimates to complete the analysis.

Iorio and colleagues calculated that switching from the standard-half-life nonacog alfa to N9-GP would result in a 9.4% reduction in overall annual treatment costs, partly due to a significant reduction in annualized bleed rates. Switching from eftrenonacog alfa to N9-GP would cut costs by 10.5%, though the reduction in annualized bleed rates did not achieve statistical significance.

The authors also found that N9-GP led to a reduction in the prophylactic FIX consumption, which also reduced costs.

“The findings of this study have important implications for decision-makers when it comes to evaluating new medicines for procurement,” Iorio and colleagues said. “In particular, clinical outcomes associated with a potential new therapy should be taken into consideration and not just treatment costs.”

In this case, the investigators said, the switch created a win-win scenario, because it likely cut costs while at the same time improving patient outcomes.

Reference

Iorio A, MacDonald V, Caillaud A, et al. Treatment switch to nonacog beta pegol factor IX in hemophilia B: A Canadian cost-consequence analysis based on real-world factor IX consumption and clinical outcomes. Res Pract Thromb Haemost. 2023;7(3):100106. Published online March 11, 2023. doi:10.1016/j.rpth.2023.100106