Cost-Effectiveness Analysis of Recombinant Factor VIII Fc-Fusion Protein (rFVIIIFc) for the Treatment of Severe Hemophilia A in Italy Incorporating Real-World Dosing and Joint Health Data

Cost-utility analysis of emicizumab for the treatment of severe hemophilia A patients in Canada

INTRODUCTION

EHL FVIII products and emicizumab provide clinicians with other prophylactic options for treating hemophilia A, however, it is unclear if emicizumab is a cost-saving option. The objective of this study is to estimate the health and economic effects of using prophylactic EHL FVIII, SHL FVIII, and emicizumab in severe haemophilia A patients.

MATERIALS AND METHODS

A state-transition Markov model evaluated the cost-effectiveness of prophylactic SHL FVIII, EHL FVIII, and emicizumab in a cohort of 2-year-old male patients over a lifetime horizon in the form of a cost-utility analysis using a Canadian provincial ministry of health payer perspective. The transition probabilities, costs, and utilities were obtained from literature and the Canadian Bleeding Disorders Registry. Probabilistic sensitivity and scenario analyses were performed to test the robustness of the model.

RESULTS

The base-case analysis, over a lifetime horizon, resulted in a total cost and utilities per person for SHL FVIII, EHL FVIII, and emicizumab of $27.2 million (M), $36.7 M, and $26.2 M, respectively, and 31.30, 31.16, and 31.61 quality-adjusted life years, respectively. Emicizumab treatment resulted in 29 and 16 less bleeds in a lifetime compared to SHL FVIII and EHL FVIII, respectively. Probabilistic sensitivity analysis showed that emicizumab was cost-saving 100% of the time compared to SHL FVIII and EHL FVIII.

CONCLUSION

The cost-utility analysis showed that emicizumab is more effective and may be less costly than FVIII for Canadian haemophilia A patients, conditional on drug cost assumptions. Our model indicates that emicizumab may be a potentially favourable treatment option for minimising healthcare costs and providing higher effectiveness.

Proof-of-Concept Study of a 3-D Ultrasound Scanner Used for Ankle Joint Assessment

Joint arthropathies often require continuous monitoring of the joint condition, typically performed using magnetic resonance (MR) or ultrasound (US) imaging. US imaging is often the preferred screening or diagnostic tool as it is fast and inexpensive. However, conventional 2-D US has limited capability to compare imaging results between examinations because of its operator dependence and challenges related to repeat imaging in the same location and orientation. Comparison between several imaging sessions is crucial to assess the interval progression of joint conditions. We propose a novel 3-D US scanner for ankle joint assessment that can partially overcome these issues by enabling 3-D imaging. Here, we (i) present the design of the 3-D US ankle scanner system, (ii) validate the geometric reconstruction accuracy of the system, (iii) provide preliminary images of healthy volunteer ankles and (iv) compare 3-D US imaging results with MR imaging. The 3-D ankle scanner consists of a tub filled with water, a linear US probe attached to the wall of the tub and a motorized unit that rotates the US probe 360° around the center of the tub. As the probe rotates, a 3-D US image is formed of the ankle of the patient positioned in the middle of the tub. US probe height, angle and distance from the tub center can be adjusted. The reconstruction accuracy of the system was validated in each of the coordinate directions at different probe angles using two test phantoms. A phantom consisting of numerous Ø200-µm nylon threads with known spacing and a metal rod with machined grooves was used for validation in the horizontal and vertical directions, respectively. The volumetric reconstruction accuracy validation was performed by imaging an agar phantom with two embedded spheres of known volumes and comparing the segmented sphere volume and surface area with the expected. Three-dimensional US and MR images of both ankles of five healthy volunteers were acquired. Distal tibia and proximal talus were segmented in both imaging modalities and the surfaces of these segmentations were compared using the 95% Hausdorff and mean surface distances. The observed mean linear measurement error in all the coordinate directions and over several probe angles was 2.98%. The mean measured volumetric measurement error was 3.45%. The volunteer study revealed useful features for joint assessment present in the 3-D ankle scanner images, such as joint spacing, distal tibia and proximal talus. The mean 95% Hausdorff and mean surface distances between segmentations in 3-D US and MR images were 5.68 ± 0.83 and 2.01 ± 0.30 mm, respectively. In this proof-of-concept study, the 3-D US ankle scanner enabled visualization of the ankle joint features that are useful for joint assessment.

Cost-minimization analysis of recombinant factor VIII Fc versus emicizumab for treating patients with hemophilia A without inhibitors in Europe

BACKGROUND AND OBJECTIVE

A cost-minimization model was developed to compare recombinant factor VIII Fc (rFVIIIFc) and emicizumab as prophylaxis for hemophilia A without inhibitors.

METHODS

The model was based on 100 patients from the healthcare payer perspective in the UK, France, Italy, Spain, and Germany (5-year time horizon). Costs included: drug acquisition; emicizumab wastage by bodyweight (manufacturer's dosing recommendations); and additional FVIII for breakthrough bleeds. Scenario analyses (UK only): reduced emicizumab dosing frequency; and emicizumab maximum wastage.

RESULTS

Total incremental 5-year savings for rFVIIIFc rather than emicizumab use range from €89,320,131 to €149,990,408 in adolescents/adults (≥12 years) and €173,417,486 to €253,240,465 in children (<12 years). Emicizumab wastage accounts for 6% of its total cost in adolescents/adults and 26% in children. Reducing the emicizumab dosing frequency reduces the incremental cost savings with rFVIIIFc, but these remain substantial (adolescents/adults, >€92 million; children >€32 million). Maximum emicizumab wastage increases by 86% and 106%, respectively, increasing the incremental cost savings with rFVIIIFc to €125,352,125 and €105,872,727, respectively.

CONCLUSION

Based on cost-minimization modeling, rFVIIIFc use for hemophilia A prophylaxis in patients without inhibitors is associated with substantial cost savings in Europe, reflecting not only higher acquisition costs of emicizumab, but also other costs including wastage related to available vial sizes.

A survey of physicians' treatment switching practice in people on long-term prophylaxis for hemophilia in five European countries

OBJECTIVE

Recombinant factor VIII and factor IX Fc fusion proteins (rFVIIIFc and rFIXFc) were developed with an extended half-life (EHL) to improve the management of people with hemophilia A (PwHA) and B (PwHB), respectively.

METHODS

This survey gathered physician-reported treatment decisions and physician views on outcomes in PwHA or PwHB who switched to rFVIIIFc or rFIXFc in the 12 months prior to study completion.

RESULTS

Physicians (N = 37) considered bleeds, pharmacokinetic parameters, joint health and adherence the most important factors to assess both in routine care and when deciding to switch to an EHL therapy. In the 12 months prior to study completion, 37 physicians switched 113 PwHA to rFVIIIFc and 25 physicians switched 36 PwHB to rFIXFc. Most PwH (>90%) had moderate or severe hemophilia and many (>60%) switched within 6 months of the survey. The main reason for switching PwHA to rFVIIIFc was to allow fewer injections (49%), while the main reason for switching PwHB to rFIXFc was the product becoming available for use (36%). Overall, 96% of PwHA and 89% of PwHB who were switched remained on these EHL products at the time of survey. Mean total weekly dose, injection frequency and annualized bleeding rate were reported to have reduced following switching.

CONCLUSION

This survey provides valuable insight into reasons for, and challenges to, the use of EHL products in clinical practice. Physicians perceived that switching to treatment with rFVIIIFc or rFIXFc can improve quality of life, treatment burden, disease control and adherence.

Cost-Effectiveness Analysis of rFVIIIFc Versus Contemporary rFVIII Treatments for Patients with Severe Hemophilia A Without Inhibitors in the United States

BACKGROUND

A range of treatments for patients with severe hemophilia A (HA) have been developed over the last decade, allowing for reduced frequency of administration and improved outcomes (joint health and breakthrough bleeding rates). While clinically effective, the cost effectiveness of these treatments has not been established.

OBJECTIVE

This study presents a cost-effectiveness analysis of contemporary rFVIII treatments for severe HA patients without inhibitors.

METHODS

A published semi-Markov model was used to compare three different prophylaxis regimens: (1) extended half-life (EHL) recombinant Factor VIII (rFVIII) Fc-fusion protein (rFVIIIFc, Eloctate^®, Sanofi), (2) EHL PEGylated rFVIII (PEG-rFVIII, Adynovate^®, Takeda), and (3) standard half-life (SHL) rFVIII (antihemophilic factor [recombinant], Advate^®, Takeda), used as a proxy for all SHL rFVIII treatments. Acquisition costs were included based on published dosing and weight data. Benefits were incorporated through published annualized bleeding rates, rates of target joint development/resolution, and improvements in the modified hemophilia joint health score. Results were presented as total, discounted costs, and quality-adjusted life-years (QALYs).

RESULTS

rFVIIIFc was shown to provide the most QALYs (27.922) compared with both PEG-rFVIII (27.454) and SHL rFVIII (27.071), at lower costs. Discounted lifetime costs were estimated at US$18.235m (rFVIIIFc), US$20.198m (PEG-rFVIII), and US$18.285m (SHL rFVIII), and were predominantly affected by model settings related to acquisition costs, patient weight, and dosing.

CONCLUSIONS

rFVIIIFc may offer a cost-effective option for severe HA patients. Uncertainties owing to the limited evidence base is the main limitation of the study.

Efmoroctocog Alfa: A Review in Haemophilia A

Efmoroctocog alfa (Elocta®, Eloctate®, Eloctate™), an extended half-life (EHL) recombinant factor VIII (rFVIII)-Fc fusion protein, is approved for the treatment and prophylaxis of bleeding in patients with haemophilia A. The efficacy of efmoroctocog alfa in the prevention and treatment of bleeding in previously treated patients (PTPs) and previously untreated patients (PUPs) with severe haemophilia A has been demonstrated in phase III studies; this includes its use in the perioperative setting (in PTPs). Furthermore, the effectiveness of efmoroctocog alfa in clinical practice has been confirmed in numerous real-world studies; compared with conventional, standard half-life (SHL) FVIII products, prophylaxis with this EHL FVIII product achieved similar or reduced bleeding rates with fewer injections. Efmoroctocog alfa was generally well tolerated; inhibitors occurred in approximately one-third of PUPs in a phase III study. Efmoroctocog alfa is an established and effective EHL FVIII replacement therapy for the management of haemophilia A. Compared with SHL FVIII products, EHL FVIII products such as efmoroctocog alfa have the potential to optimise prophylactic outcomes by decreasing the burden of treatment or increasing the level of bleed protection.

Bleeding outcomes and factor utilization after switching to an extended half-life product for prophylaxis in haemophilia A in Austria

To prevent bleeding in severe haemophilia A [SHA, defined as factor VIII (FVIII) activity < 1%] regular prophylactic FVIII replacement therapy is required, and the benefits of factor products with extended half-life (EHL) over traditional standard half-life (SHL) are still being debated. We performed a multi-centre, retrospective cohort study of persons with SHA in Austria aiming to compare clinical outcomes and factor utilization in patients with SHA, who switched from prophylaxis with SHL to an EHL. Data were collected from haemophilia-specific patient diaries and medical records. Twenty male persons with SHA (median age: 32.5 years) were included. The most common reason for switching to the EHL was a high bleeding rate with SHL. Switch to rFVIII-Fc resulted in a significantly decreased annualized bleeding rate (ABR; median difference (IQR): − 0.3 (− 4.5–0); Wilcoxon signed-rank test for matched pairs: Z = − 2.7, p = 0.008) and number of prophylactic infusions per week (− 0.75 (− 1.0–0.0); Z = − 2.7, p = 0.007). Factor utilization was comparable to prior prophylaxis with SHL (0.0 (− 15.8–24.8) IU/kg/week; Z = − 0.4, p = 0.691). In summary, switch to EHL (rFVIII-Fc) was associated with an improved clinical outcome, reflected by ABR reduction, and less frequent infusions, without significantly higher factor usage.

Recombinant FVIIIFc Versus BAY 94-9027 for Treatment of Patients with Haemophilia A: Comparative Efficacy Using a Matching Adjusted Indirect Comparison

Introduction

Prophylaxis with recombinant factor VIII (rFVIII) is the current standard of care for haemophilia A. Several approaches have been used to extend the half-life of rFVIII to improve prophylaxis outcomes. An indirect comparison of pivotal clinical trial data was performed to evaluate the relative efficacy of two extended half-life therapies approved for the prophylactic treatment of haemophilia A: recombinant FVIII–IgG₁ Fc domain fusion protein (rFVIIIFc) and pegylated rFVIII (BAY 94-9027).

Methods

Matching-adjusted indirect comparison (MAIC) was conducted to compare the rFVIIIFc individualised prophylaxis arm of the A-LONG phase III clinical trial (n = 117) and the BAY 94-9027 approved dosing regimens of the PROTECT VIII phase II/III study (n = 110). Following matching for baseline characteristics, mean annualised bleeding rate (ABR) and the proportion of patients with zero bleeds were compared for rFVIIIFc and BAY 94-9027. Additional supportive analyses comparing rFVIIIFc individualised prophylaxis and the individual prophylaxis regimens included in the PROTECT VIII group (twice weekly, and every 5 and 7 days [Q5D and Q7D]) were conducted.

Results

Mean ABR was lower in the rFVIIIFc individualised prophylaxis group versus the BAY 94-9027 pooled prophylaxis population (3.0 versus 4.9), providing a clinically relevant and statistically significant difference (mean difference [MD] − 1.9; 95% confidence interval [CI] − 3.5 to − 0.4). A statistically significant difference in ABR was also observed for rFVIIIFc compared with BAY 94-9027 Q7D (3.2 versus 6.4; MD − 3.3; 95% CI − 6.4 to − 0.2). The difference in the proportion of patients with zero bleeds between rFVIIIFc (46.5%) and BAY 94-9027 pooled prophylaxis population (38.2%) was not statistically significant (odds ratio 1.4; 95% CI 0.8 to 2.5).

Conclusions

This indirect treatment comparison indicates a statistically significant and clinically relevant difference in ABR favouring individualised prophylaxis with rFVIIIFc versus BAY 94-9027 prophylaxis. The proportion of patients with zero bleeds was numerically greater with rFVIIIFc treatment but did not achieve statistical significance.

Cost of patients with hemophilia A treated with standard half-life or extended half-life FVIII in Spain

BACKGROUND

In a real-world analysis (RWA) conducted in the United States (US), median international units (IUs) of extended half-life (EHL) recombinant coagulation factor VIII (rFVIII) dispensed were 10% to 45% greater than standard half-life (SHL) rFVIII. The mean IUs of each rFVIII dispensed quarterly were obtained from two databases (N = 776).

METHODS

A probabilistic model in a 1-year time horizon was used in order to analyze the cost comparison of SHL and EHL rFVIII products in Spain. In this analysis, mean IUs were those of the RWA, and frequency of use and prices for each rFVIII were obtained from sales estimates based on Spanish sources (IQVIA; €, 2019).

RESULTS

Data showed an average annual savings per patient of €11,227 for SHL rFVIII versus EHL rFVIII products, with a savings probability of 75.5%. The results were stable in the sensitivity analyses. Not switching treatment from SHL to EHL rFVIII resulted in greater savings per patient (€53,078), with a savings probability of 99.9%. Considering the frequency of rFVIII dispensation in the US, annual savings per patient would increase to €16,350 in Spain, with a savings probability of 79.9%.

CONCLUSIONS

According to this model, use of SHL rFVIII versus EHL rFVIII products could lead to savings for the Spanish National Health System.