Indirect comparisons of efficacy and weekly factor consumption during continuous prophylaxis with recombinant factor VIII Fc fusion protein and conventional recombinant factor VIII products

Prophylaxis with a recombinant factor VIII Fc in hemophilia A: long-term follow-up on joint health, efficacy, and safety from phase 3 studies in children and adults

Background

Recurrent joint bleeds are a major cause of morbidity in severe hemophilia. Prophylaxis with efmoroctocog alfa (a recombinant factor VIII Fc fusion protein, [rFVIIIFc]) has demonstrated benefits beyond bleed control, including joint health maintenance.

Objectives

To assess long-term efficacy and safety of rFVIIIFc prophylaxis in severe hemophilia A in phase 3 pivotal (A-LONG/Kids A-LONG) and extension (ASPIRE) studies.

Methods

Longitudinal analysis included pooled data from A-LONG/Kids A-LONG and ASPIRE. Subgroup analyses investigated outcomes in modified Hemophilia Joint Health Score or Hemophilia Joint Health Score and target joints in subjects with 4 to 5 years follow-up on individualized prophylaxis (IP), and those with the highest annualized bleeding rate (ABR) quartile during Year 1 of IP.

Results

Overall, rFVIIIFc consumption remained stable and low ABRs were maintained, with a median treatment duration of 4.2/3.4 years in subjects from A-LONG/Kids A-LONG, respectively. Median overall ABR also remained low (1.0-2.0) in subjects on IP for 4 to 5 years. Sustained improvements in modified Hemophilia Joint Health Score or Hemophilia Joint Health Score were demonstrated over a median follow-up of 3.7 years. In subjects from A-LONG/Kids A-LONG, 99.6% (n = 234)/100% (n = 9) of evaluable baseline target joints were resolved, with no recurrence in 95%/100% of target joints. In IP subjects within the highest ABR quartile in Year 1, continued improvements were observed over a median follow-up of 4.3 years in ABR and joint health, without increased factor consumption. No inhibitors or treatment-related serious adverse events were reported.

Conclusion

Previously treated subjects of all ages receiving long-term prophylaxis with rFVIIIFc had sustained clinical benefits, including improved joint health and low ABR.

Switching from standard to extended half-life FVIII prophylaxis in haemophilia A: Comparison of factor product use, bleed rates and pharmacokinetics

INTRODUCTION

Majority of haemophilia A patients in our comprehensive care centre have switched from standard half-life (SHL) to extended half-life (EHL) FVIII products in a short time.

AIM

We compared the clinical and laboratory outcomes between SHL and EHL FVIII prophylaxis in product switchers.

METHODS

This is a retrospective inception cohort of all adult haemophilia A patients switched to EHL (rFVIIIFc or rFVIII-PEG) prophylaxis in our centre. Dosing, product utilization, annualized bleed rates (ABR), treatment regimen and pharmacokinetics by Web Accessible Population Pharmacokinetic Service (WAPPS)-Hemo were compared between SHL and EHL.

RESULTS

We included 38 patients, whose median age was 38 years (range 17-75). Median FVIII dose was 23 IU/kg for SHL versus 25 IU/kg for EHL. After switching, weekly infusions decreased by 29% from median 2.8 (every 2.5 days) to 2.0 (every 3.5 days) (P = <.001) and factor consumption for prophylaxis by 17% from 60 to 50 IU/kg/week (P = <.001). Weekly infusions decreased in 71% and FVIII utilization in 55% of patients. ABR remained low (1.0 for SHL and .5 for EHL, respectively). In pharmacokinetics, the half-life of FVIII increased from median 13 to 21 h after switching. Times above .01 and .03 IU/ml improved from 85 to 131 h and from 65 to 106 h. Half-lives of the SHL products and von Willebrand factor levels predicted half-lives with the EHL products.

CONCLUSIONS

Our cohort study confirms the successful experience of switching to EHL FVIII products, with decreased infusion frequency, factor consumption and excellent clinical efficacy.

Analysis of pooled real-world data from Germany, Italy, and the United States of rVIII-SingleChain compared with standard- and long-acting FVIII products for prophylaxis of hemophilia A

OBJECTIVE

To evaluate real-world annualized bleeding rates (ABRs), dosing frequency, and factor consumption of four recombinant FVIII (rFVIII) products using pooled data from centers in the US, Germany, and Italy.

METHODS

De-identified patient medical chart data were collected from 48 hemophilia treatment centers in the US, Germany, and Italy. Patients included in this analysis had hemophilia A and were treated with rVIII-SingleChain, rFVIIIFc, octocog alfa, or BAY 81-8973 for ≥12 weeks. Where possible, patient selection considered age and disease severity in order to balance patient groups across products. Summary statistics were presented descriptively by product for dosing frequency, consumption, ABR/annualized spontaneous bleeding rate (AsBR), and corresponding percentage of patients with zero bleeds. Logistic regression was performed for patients with zero bleeds or zero spontaneous bleeds (vs. patients with any such bleeds). Generalized linear model regression was performed for ABR, AsBR, and consumption. All regression models included the product variable for comparison as well as additional independent variables for adjustment (age, weight, severity, and country for the consumption model, with the addition of consumption for the bleeding outcomes models).

RESULTS

Overall, 616 patients were included (rVIII-SingleChain, n = 129; rFVIIIFc, n = 159; octocog alfa, n = 181; BAY 81-8973, n = 147). Dosing frequency was ≤2 times a week for 65.9%, 75.5%, 25.4%, and 40.1% of patients treated with rVIII-SingleChain, rFVIIIFc, octocog alfa, and BAY 81-8973, respectively. ABRs were not significantly different among products, with mean (median) values of 1.1 (0.0), 1.0 (0.0), 1.4 (1.0), and 1.9 (1.0) for rVIII-SingleChain, rFVIIIFc, octocog alfa, and BAY 81-8973, respectively. The percentage of patients with zero bleeds was comparable between rVIII-SingleChain and rFVIIIFc (59.7% vs. 62.3%; p =.916) and significantly higher for rVIII-SingleChain compared with octocog alfa (p <.001) and BAY 81-8973 (p =.003). Comparison of mean weekly consumption showed: rVIII-SingleChain (83.0 IU/kg/week) vs. rFVIIIFc (96.9; p =.055) and significantly lower for rVIII-SingleChain vs. octocog alfa (108.6; p <.001) and BAY 81-8973 (104.3; p =.001). The median values for weekly consumption were 85.7, 90.1, 100.1, and 98.5 IU/kg/week for rVIII-SingleChain, rFVIIIFc, octocog alfa, and BAY 91-8973, respectively. Similar trends were observed for all outcomes when analyzing the subgroups of patients aged ≥12 years and patients with severe disease (all age and ≥12 years).

CONCLUSIONS

rVIII-SingleChain prophylaxis may provide improved bleed protection, less frequent dosing, and lower consumption compared with standard-acting FVIII products, and comparable protection and consumption to the other long-acting FVIII product, in patients with hemophilia A.

Predicting Individual Changes in Terminal Half-Life After Switching to Extended Half-Life Concentrates in Patients With Severe Hemophilia

Predicting individual effects of switching from standard half-life (SHL) to extended half-life (EHL) FVIII/FIX concentrates is pivotal in clinical care, but large-scale individual data are scarce. The aim of this study was to assess individual changes in terminal half-life (THL) after switching to EHL concentrates and identifying determinants of a clinically relevant THL extension in people with severe hemophilia. Data from participants with pharmacokinetic studies on both SHL and EHL were extracted from the Web-Accessible Population Pharmacokinetics Service (WAPPS) database and stratified according to hemophilia type and age groups (children/adults). A 30% increase in THL was considered clinically relevant. Predictors of a relevant increase were identified using logistic regression. Data from 688 persons with severe hemophilia (2174 infusions) were included: 89% hemophilia A; median age: 21.7 (interquartile range [IQR]: 11.5–37.7); positive inhibitor history: 11.7%. THL increased by 38% (IQR: 17%–67%) and 212% (139%–367%) for hemophilia A and B, respectively. All EHL-FIX concentrate users showed clinically relevant THL extension. However, 40% (242/612) of people with hemophilia A showed limited extension or decrease in THL after switching. Relevant FVIII-THL extension was predicted by short baseline THL and blood group non-O in both children and adults. In conclusion, clinically relevant THL extension was observed in all 75/76 participants switching to EHL-FIX, and in 60% of 612 switching to EHL-FVIII. Short THL on SHL-FVIII and blood group non-O were identified as predictors for a relevant THL increase after switching to EHL-FVIII. Individualized pharmacokinetic assessment may guide clinical decision-making when switching from SHL to EHL-FVIII.

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.

Efficacy, safety, and immunogenicity of rurioctocog alfa pegol for prophylactic treatment in previously treated patients with severe hemophilia A: a systematic review and meta-analysis of clinical trials

Background: Patients with severe hemophilia often present with painful joint and soft tissue bleeding which may restrict them from their daily activities. The current standard of care still relies on a regular prophylactic factor VIII (FVIII), which has a high daily treatment burden. Recently, rurioctocog alfa pegol, a third-generation recombinant FVIII with a modification in its polyethylene glycol (PEG) component, has been developed. Several trials have studied this synthetic drug as bleeding prophylaxis in severe hemophilia A. This study aims to evaluate the efficacy, safety, and immunogenicity of rurioctocog alfa pegol for previously treated patients with severe hemophilia A. Methods: This study was conducted in conformity with the PRISMA guidelines. Data were retrieved from PubMed, Scopus, Cochrane Library, Wiley Online Library, and CINAHL (via EBSCOhost). Study qualities were assessed using the Methodological Index for Non-Randomized Studies (MINORS) and Modified Jadad scales. Results: Four studies involving 517 previously treated severe hemophilia A patients were included in this study. The pooled mean of total annualized bleeding rate (ABR) and hemostatic efficacy was 2.59 (95% CI = 2.04-3.14) and 92% (95% CI = 85%-97%), respectively. Only 30 (2.3%) non-serious and one (1.4%) serious adverse events were considered related to rurioctocog alfa pegol treatment. At the end of the studies, no development of FVIII inhibitory antibodies was observed. None of the developed binding antibodies to FVIII, PEG-FVIII, or PEG was correlated to the treatment efficacy and safety. Conclusions: Despite the limited availability of direct comparison studies, our analyses indicate that rurioctocog alfa pegol could serve as a safe and effective alternative for bleeding prophylaxis in previously treated hemophilia A patients. Moreover, it appears to have low immunogenicity, which further increases the safety profile of the drug in such clinical conditions.

Efficacy, safety, and immunogenicity of rurioctocog alfa pegol for prophylactic treatment in previously treated patients with severe hemophilia A: a systematic review and meta-analysis of clinical trials

Background: Patients with severe hemophilia often present with painful joint and soft tissue bleeding which may restrict them from their daily activities. The current standard of care still relies on a regular prophylactic factor VIII (FVIII), which has a high daily treatment burden. Recently, rurioctocog alfa pegol, a third-generation recombinant FVIII with a modification in its polyethylene glycol (PEG) component, has been developed. Several trials have studied this synthetic drug as bleeding prophylaxis in severe hemophilia A. This study aims to evaluate the efficacy, safety, and immunogenicity of rurioctocog alfa pegol for previously treated patients with severe hemophilia A. Methods: This study was conducted in conformity with the PRISMA guidelines. Data were retrieved from PubMed, Scopus, Cochrane Library, Wiley Online Library, and CINAHL (via EBSCOhost). Study qualities were assessed using the Methodological Index for Non-Randomized Studies (MINORS) and Modified Jadad scales. Results: Four studies involving 517 previously treated severe hemophilia A patients were included in this study. The pooled mean of total annualized bleeding rate (ABR) and hemostatic efficacy was 2.59 (95% CI = 2.04-3.14) and 92% (95% CI = 85%-97%), respectively. Only 30 (2.3%) non-serious and one (1.4%) serious adverse events were considered related to rurioctocog alfa pegol treatment. At the end of the studies, no development of FVIII inhibitory antibodies was observed. None of the developed binding antibodies to FVIII, PEG-FVIII, or PEG was correlated to the treatment efficacy and safety. Conclusions: Despite the limited availability of direct comparison studies, our analyses indicate that rurioctocog alfa pegol could serve as a safe and effective alternative for bleeding prophylaxis in previously treated hemophilia A patients. Moreover, it appears to have low immunogenicity, which further increases the safety profile of the drug in such clinical conditions.

Efficacy safety and immunogenicity of rurioctocog alfa pegol for prophylactic treatment in previously treated patients with severe hemophilia A: a systematic review and meta-analysis of clinical trials

Background: Patients with severe hemophilia often present with painful joint and soft tissue bleeding which may restrict them from their daily activities. The current standard of care still relies on a regular prophylactic factor VIII (FVIII), which has a high daily treatment burden. Recently, rurioctocog alfa pegol, a third-generation recombinant FVIII with a modification in its polyethylene glycol (PEG) component, has been developed. Several trials have studied this synthetic drug as bleeding prophylaxis in severe hemophilia A. This study aims to evaluate the efficacy, safety, and immunogenicity of rurioctocog alfa pegol for previously treated patients with severe hemophilia A. Methods: This study was conducted in conformity with the PRISMA guidelines. Data were retrieved from PubMed, Scopus, Cochrane Library, Wiley Online Library, and CINAHL (via EBSCOhost). Study qualities were assessed using the Methodological Index for Non-Randomized Studies (MINORS) and Modified Jadad scales. Results: Four studies involving 517 previously treated severe hemophilia A patients were included in this study. The pooled mean of total annualized bleeding rate (ABR) and hemostatic efficacy was 2.59 (95% CI = 2.04-3.14) and 92% (95% CI = 85%-97%), respectively. Only 30 (2.3%) non-serious and one (1.4%) serious adverse events were considered related to rurioctocog alfa pegol treatment. At the end of the studies, no development of FVIII inhibitory antibodies was observed. None of the developed binding antibodies to FVIII, PEG-FVIII, or PEG was correlated to the treatment efficacy and safety. Conclusions: Despite the limited availability of direct comparison studies, our analyses indicate that rurioctocog alfa pegol could serve as a safe and effective alternative for bleeding prophylaxis in previously treated hemophilia A patients. Moreover, it appears to have low immunogenicity, which further increases the safety profile of the drug in such clinical conditions.

Redefining prophylaxis in the modern era

Prophylaxis is the globally accepted standard of care for persons with haemophilia and presents many advantages over episodic treatment. The prophylaxis benefits include bleed reduction, reduction in musculoskeletal complications and improvement in the quality of life. The currently evolving novel therapies for the management of haemophilia has ushered a new era characterized by improved prophylaxis targets and outcomes. These redefined targets and outcomes have necessitated the need to also redefine prophylaxis. In this state-of-the-art review, we redefine prophylaxis in the modern era by revisiting its definition, presenting data to support higher trough levels to achieve with prophylaxis and introducing steady-state haemostasis as a possible new target for prophylaxis.

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.

A systematic review evaluating the efficacy and factor consumption of long-acting recombinant factor VIII products for the prophylactic treatment of hemophilia A

AIMS

Long-acting (LA) recombinant FVIII (rFVIII) products with extended dosing intervals have been developed for the treatment of hemophilia A; however, no direct head-to-head trial has been conducted to compare the efficacy of these products.

MATERIALS AND METHODS

A systematic literature search was conducted to identify published Phase III clinical trials of prophylactic LA rFVIII treatment in previously treated patients aged ≥12 years, with moderate-to-severe hemophilia A (endogenous FVIII levels ≤2%). Studies that did not meet these criteria, or did not report the included outcomes, were excluded. Bleeding rates and consumption were extracted and summarized; only data for the dosing frequencies indicated in the US product labels (which are similar to those indicated in the European Medicines Agency labels) were included.

RESULTS

Five articles met the inclusion criteria; these studies only included patients with severe hemophilia A. Treatment length, reported outcomes and dose (range: 20-65 IU/kg) varied between studies. Median annualized bleeding rate (ABR) (IQR) reported in the relevant studies was 1.14 (0.00-4.30), rVIII-SingleChain 2 or 3 times weekly; 1.6 (0.0-4.7), rFVIIIFc 2 times weekly followed by every 3-5 days; 1.9 (0.0-5.8), BAX855 2 times weekly; 1.18 (0.00-4.25), N8-GP every 4 days; 1.9 (0.0-5.2) and 4.1 (2.0-10.6), BAY 94-9027 2 times weekly for the cohort who experienced >1 or <1 bleed in the study run-in phase, respectively. Median spontaneous ABR was 0.0 across studies reporting relevant data. Reported consumption was comparable among all LA products.

LIMITATIONS

The primary limitation of this systematic review was the variation in study design and not all studies reported all desired outcomes, which limited the quantity of data available.

CONCLUSIONS

This systematic review identified pivotal trial data for LA rFVIII products. Real-world evidence is needed to understand how these products perform in clinical practice.

Real-world outcomes associated with standard half-life and extended half-life factor replacement products for treatment of haemophilia A and B

: Standard-of-care treatment for haemophilia A or B is to maintain adequate coagulation factor levels through clotting factor administration. The current study aimed to evaluate annualised bleeding rates (ABR) and treatment adherence for haemophilia A or B patients receiving standard half-life (SHL) vs. extended half-life (EHL) factor replacement products. We analysed data from the Adelphi Disease-Specific Programmes, a health record-based survey of United States and European haematologists. Analysis included 651 males with moderate-to-severe haemophilia A or B (the United States, n = 132; Europe, n = 519). The haemophilia A analysis included 501 patients (SHL, n = 435; EHL, n = 66). In the combined United States/European population, mean (SD) ABR was 1.7 (1.69) for the SHL group and 1.8 (2.00) for the EHL group. A total of 72% of patients receiving SHL factor VIII and 75% of patients receiving EHL factor VIII in the combined population were fully adherent (no doses missed of the last 10 doses), as reported by physicians. The haemophilia B analysis included 150 patients (SHL, n = 114; EHL, n = 36). The mean (SD) ABR in the combined population was 2.1 (2.16) for patients receiving SHL factor IX (FIX) and 1.4 (1.48) for patients receiving EHL FIX. The percentage of fully adherent patients (physician-reported) was similar in both treatment groups (SHL FIX, 68%; EHL FIX, 73%). In this preliminary real-world survey in a relatively small sample of patients, measures of ABR and adherence between SHL and EHL products were evaluated. Additional real-world research on prescribing patterns, SHL vs. EHL effectiveness, and adherence is warranted.

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.

A Retrospective Observational Study of Rurioctocog Alfa Pegol in Clinical Practice in the United States

BACKGROUND

Research describing patient experience and outcomes with extended half-life recombinant factor VIII (EHL rFVIII) outside of clinical trials is limited. Real-world rFVIII consumption studies, when people with hemophilia A (PWHA) switch from standard half-life (SHL) to EHL rFVIII, may help payers and clinicians make more informed treatment choices.

OBJECTIVE

To conduct a retrospective, observational, U.S.-based analysis to describe clinical and demographic profiles of PWHA who switched to prophylactic rurioctocog alfa pegol.

METHODS

Data were obtained from PWHA treated by 38 prescribers across 21 states using specialty pharmacy database case report forms, electronic medical records, and direct communication with providers, PWHA, or their guardians. Assessments included disease severity, pain severity, number and location of target joints, prior HA therapy, reasons for switching, treatment duration, dosing frequency, adherence, and annualized bleeding rates (ABRs) before and after switching to rurioctocog alfa pegol from SHL or another EHL rFVIII.

RESULTS

Data were collected from 56 PWHA. The mean age was 26 years (range = 5-88); median age was 24 years (interquartile range = 14-34); 20% were aged < 12 years; and 89% (50/56) had severe HA. All PWHA had ≥ 12 months of rFVIII treatment before switching to rurioctocog alfa pegol. The population had a mean 1.8 target joints. Baseline subjective pain assessment was mild to moderate for 68% (38/56) of respondents. Before receiving rurioctocog alfa pegol, most PWHA received antihemophilic factor (recombinant) for prophylaxis (73%, 41/56) or breakthrough bleeding (59%, 33/56). Mean dosing frequency for prior prophylaxis was 2.8 per week for SHL rFVIII and 1.8 per week for EHL rFVIII, and 2.2 per week for all PWHA after switching to rurioctocog alfa pegol prophylaxis. The median time on rurioctocog alfa pegol prophylaxis was 12.0 months versus 80.8 months on previous SHL rFVIII and 13.5 months on previous EHL rFVIII. Mean ABRs on prior prophylaxis were 5.9 for SHL rFVIII (n = 35) and 4.7 for EHL rFVIII (n = 3). After switching to rurioctocog alfa pegol, the overall mean ABR reduced by 71% (5.8 to 1.7, P < 0.001) and 20/56 PWHA had no bleeding events. There was also a 20.9% reduction in the mean days per week of factor administration (P < 0.001) after switching to prophylactic rurioctocog alfa pegol. For 47 PWHA who switched from SHL rFVIII, their weekly dose decreased from 109.8 to 100.6 IU per kg with rurioctocog alfa pegol (P = 0.094). The proportion of PWHA with good/complete treatment adherence increased from 68% (38/56) on any prior rFVIII to 80% (45/56) on rurioctocog alfa pegol. The most common reason PWHA switched to rurioctocog alfa pegol was to reduce treatment infusions.

CONCLUSIONS

Switching from either an SHL or EHL rFVIII to rurioctocog alfa pegol is associated with fewer bleeding episodes owing to more effective prophylaxis and improved adherence. Those who switched from an SHL rFVIII reported reduced factor consumption with rurioctocog alfa pegol. This long-acting factor is an important additional option for the care of PWHA.

DISCLOSURES

This study was funded by Shire Development LLC, a Takeda company, Lexington, MA. Trio Health was involved in study design and acquisition, analysis, and interpretation of data and was funded by Shire Development LLC, a Takeda company. Aledort serves on the data and safety monitoring boards of Baxalta U.S. Inc., a Takeda company, and Octapharma; is chair of the scientific advisory board of Kedrion; and receives consultancy fees and honoraria from Baxalta U.S. Inc., a Takeda company. Milligan is an employee of Trio Health and reports research support from AbbVie, Gilead, Merck, Sanofi, and ViiV, unrelated to this study. Watt is an employee of Shire International GmbH, a Takeda company, and owns stock in the company. Booth was an employee of Baxalta U.S. Inc., a Takeda company, at the time of this study and owns stock in the company. Data from this study were presented at the AMCP Managed Care and Specialty Pharmacy Annual Meeting; April 23-28, 2018; Boston, MA; SETH (2018) Sociedad Espanola de Trombosis y Hemostasia-XXXIV Congreso Nacional; October 11-13, 2018; Grenada, Espana; and Blood 2018 Annual Scientific Meeting; October 21-24, 2018; Brisbane, Australia.

Comparing Factor Use and Bleed Rates in U.S. Hemophilia A Patients Receiving Prophylaxis with 3 Different Long-Acting Recombinant Factor VIII Products

BACKGROUND

Recombinant factor VIII (rFVIII) products have been developed with improved pharmacokinetics, offering some patients the potential to extend dosing intervals, thereby reducing their dosing frequency while minimizing the occurrence of bleeding events. No clinical trials have been conducted to compare the bleeding rates and use of these long-acting products.

OBJECTIVES

To (a) assess real-world use of prophylaxis regimens in patients using 1 of 3 different long-acting products-rVIII-SingleChain, rFVIIIFc, or PEG-rFVIII; and (b) compare bleeding rates, dosing frequency, and factor consumption in 3 cohorts of patients. For rVIII-SingleChain patients, these measures were also compared with the prior products these patients used.

METHODS

De-identified patient chart data were collected from 11 hemophilia treatment centers in the United States. Patients were included if they had been treated with rVIII-SingleChain, rFVIIIFc, or PEG-rFVIII prophylaxis for ≥ 8 weeks at the time of data collection. Matching for age and disease severity was attempted between the 3 patient groups. Data were also collected for patients who switched from their prior FVIII product to prophylaxis with rVIII-SingleChain.

RESULTS

Data were obtained for 120 male patients. The majority of patients were dosing 2 times per week or less frequently (rVIII-SingleChain 65.0%, rFVIIIFc 70.0%, and PEG-rFVIII 72.5%). Annualized bleeding rates were comparable among the 3 cohorts, with median (mean) values of 2.0 (2.6) with rVIII-SingleChain and rFVIIIFc, and 3.0 (3.7) with PEG-rFVIII. The overall median (mean) FVIII consumption in IU per kg per week (IU/kg/week) was 91.9 (91.1) with rVIII-SingleChain, 108.5 (103.6) with rFVIIIFc, and 97.6 (111.0) with PEG-rFVIII, resulting in expected mean annual consumption of 322,140 IU, 361,816 IU, and 373,100 IU, respectively, for a 70 kg patient aged ≥12 years. The mean consumption was significantly different among the 3 products for all patients (P = 0.0164) and for those dosed 2 times per week (P < 0.0001). Among patients infusing 2 times per week, median (mean) consumption with rVIII-SingleChain was 83.8 (81.2) IU/kg/week, compared with 109.6 (104.4) IU/kg/week for rFVIIIFc and 92.1 (91.5) IU/kg/week for PEG-rFVIII. Additionally, switching from prophylaxis with prior FVIII products to rVIII-SingleChain increased the proportion of patients dosing ≤ 2 times per week (20% to 65%), decreased mean consumption (103.3 to 91.9 IU/kg/week; P = 0.0164), and maintained the mean annualized bleeding rates (2.9 to 2.6; P = 0.5665).

CONCLUSIONS

Results for rVIII-SingleChain confirm the findings from its pivotal trial. Analyses of annualized bleeding rates demonstrate comparable clinical outcomes of rVIII-SingleChain to the other 2 long-acting products assessed. In patients aged ≥ 12 years, rVIII-SingleChain prophylaxis may result in an 11.0% and 13.7% lower mean factor consumption than rFVIIIFc and PEG-rFVIII, respectively, representing a potential cost-saving opportunity of 34% in both cases-at the current wholesale acquisition cost of the corresponding products. In addition, in patients using rVIII-SingleChain prophylactically, consumption was reduced compared with their prior products, while bleeding control was well maintained.

DISCLOSURES

This study was funded by CSL Behring. Analyses were conducted by Adivo Associates. Maro is an employee of Adivo Associates. Desai and Yan are employees of CSL Behring. Simpson has received consulting honoraria for participation in advisory boards for CSL Behring, Genentech, Octapharma, and Bioverativ and speakers bureau for Bayer and Novo Nordisk. Data were presented in part at the Hemostasis and Thrombosis Research Society; May 9-11, 2019; New Orleans, LA, and at the International Society on Thrombosis and Haemostasis; July 6-10, 2019; Melbourne, Australia.

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

BACKGROUND

Patients with severe hemophilia A (SHA) in Italy are routinely treated with standard half-life recombinant factor VIII (rFVIII) products. rFVIII Fc-fusion protein (rFVIIIFc) is an extended half-life rFVIII product that enables less frequent administration than rFVIII, which may support improved adherence. Available data indicate low breakthrough bleed rates and potentially improved long-term joint health for patients treated with rFVIIIFc prophylaxis.

OBJECTIVE

This study assessed the cost effectiveness of rFVIIIFc versus rFVIII from an Italian healthcare perspective.

METHODS

A Semi-Markov model was constructed to assess the lifetime costs and benefits of rFVIII and rFVIIIFc prophylaxis. rFVIII product acquisition costs from a published Italian database were included for both prophylaxis and the resolution of breakthrough bleeding. Clinical outcomes within the model were determined based on published annualized bleeding rates and literature regarding the development of target joints (TJs) as the incidence of bleeds and TJs is associated with impaired health-related quality of life. Cost effectiveness was assessed using cost per quality-adjusted life-year (QALY) gained.

RESULTS

Compared with rFVIII, rFVIIIFc was associated with a per-patient cost saving of approximately €1.3 million and QALY gains of 0.39 over a lifetime horizon. Sensitivity analyses considering alternative efficacy, dosing, and structural assumptions each showed that rFVIIIFc dominated rFVIII (i.e., provided more QALYs at a reduced cost).

CONCLUSIONS

This cost-effectiveness analysis demonstrated that rFVIIIFc may offer a cost-effective treatment option for patients with SHA in Italy.

Optimising prophylaxis outcomes and costs in haemophilia patients switching to recombinant FVIII-Fc: a single-centre real-world experience

BACKGROUND

The recombinant factor VIII (rFVIII)-IgG1 Fc fusion protein (rFVIII-Fc) was the first available extended half-life rFVIII, shown to prolong dosing intervals of individualised prophylaxis in patients with severe haemophilia A, maintaining low bleeding rates and unchanged or lower FVIII dose versus standard half-life (SHL) rFVIII. Few data are available about real-world experience with rFVIII-Fc, including criteria for patient switching from SHL products, follow up and prophylaxis optimisation.

MATERIALS AND METHODS

A single-centre retrospective study was designed to review patients switched to rFVIII-Fc, based on individual needs, after pharmacokinetic (PK) assessment, according to routine clinical practice. In patients with adequate post-switch follow up, data about rFVIII-Fc prophylaxis were compared with those from the last 18-months SHL rFVIII prophylaxis.

RESULTS

Of 25 candidates, 18 patients (15 severe, 3 moderate; aged 9-62 years; 3 with inhibitor history) started rFVIII-Fc regimens, with comparable FVIII weekly dose and reduced infusion frequency (mean -30%) in all 17 patients previously on SHL rFVIII prophylaxis thrice weekly or every other day. Over a mean 18-month follow up in 13 patients, compared with SHL products, further reduced infusion frequency (mean -40%; p<0.001; interval ≥4 days in 9 patients), improved treatment satisfaction (Hemo-sat questionnaires), significantly lower FVIII weekly dose and annual consumption (mean -12%; p=0.019), comparable bleeding rates and FVIII trough levels, and improved management of breakthrough bleeding were observed. von Willebrand Factor Antigen (VWF:Ag) correlated to PK variables and both had relationships with rFVIII-Fc weekly dose, increasing statistical significance over the follow-up period. No inhibitors or drug-related adverse events were recorded.

DISCUSSION

In this real-world series of patients, a switch to rFVIII-Fc, based on careful assessment of clinical needs, PK testing and treatment monitoring, was able to optimise individual convenience, efficacy and costs of prophylaxis.

Efficacy and safety of simoctocog alfa (Nuwiq®) in patients with severe hemophilia A: a review of clinical trial data from the GENA program

Simoctocog alfa (human-cl rhFVIII, Nuwiq®) is a 4th generation recombinant FVIII (rFVIII), without chemical modification or fusion with any other protein/fragment. Nuwiq® is produced in a human embryonic kidney cell line (HEK293F), which ensures human-specific post-translational protein processing. Nuwiq® was evaluated in seven prospective clinical studies in 201 adult and pediatric previously treated patients (PTPs) with severe hemophilia A. The NuProtect study in 110 previously untreated patients (PUPs) is ongoing. The mean half-life of Nuwiq® was 15.1–17.1 h in PTP studies with adults and adolescents, and 12.5 h in children aged 2–12 years. Clinical trials in PTPs demonstrated the efficacy and safety of Nuwiq® in the prevention and treatment of bleeds and as surgical prophylaxis. In the NuPreviq study of pharmacokinetic (PK)-guided personalized prophylaxis in 66 adult PTPs, 83% of patients had no spontaneous bleeds during 6 months of personalized prophylaxis and 57% were treated ⩽2 per week. No FVIII inhibitors were detected in PTPs after treatment with 43,267 injections and >80 million IU of Nuwiq®. Interim data for 66 PUPs with ⩾20 exposure days to Nuwiq® in NuProtect demonstrated a low cumulative high-titer inhibitor rate of 12.8% [actual incidence 12.1% (8/66)] and convincing efficacy and safety.

Design of a prospective observational study on the effectiveness and real-world usage of recombinant factor VIII Fc (rFVIIIFc) compared with conventional products in haemophilia A: the A-SURE study

INTRODUCTION

Haemophilia A is a rare bleeding disorder caused by coagulation factor VIII (FVIII) deficiency. This is treated with factor VIII, conventionally using products with a half-life of 8-12 hours typically administered every 2-3 days. Recombinant FVIII Fc (rFVIIIFc) represents a new generation of products with an extended half-life allowing higher FVIII levels and longer dosing interval. The efficacy and safety of rFVIIIFc have been established in clinical studies and several years of postmarketing use. However, there remains a need to compare treatment outcome with conventional products in routine clinical use.

METHODS AND ANALYSIS

A-SURE is an ongoing, non-interventional European study with the primary objective to compare the clinical effectiveness of rFVIIIFc with conventional factor products used for haemophilia A prophylaxis. Data covering a 24-month prospective period and a 12-month retrospective period will be collected. Three primary endpoints: bleeding rate, injection frequency and factor consumption will be used to evaluate treatment outcomes. Enrolment of 175 patients on rFVIIIFc and 175 on conventional products is planned. All eligible patients from participating centres will be invited to participate. Visits and treatments follow routine clinical practice. Bias will be reduced by patient matching for age at baseline and the last weekly prophylaxis dose of a conventional product prior to baseline. Propensity scores will be calculated based on prognostic factors and potential confounders assessed at baseline and adjusted for in the estimation of the treatment effect.

ETHICS AND DISSEMINATION

Study approval was obtained by local independent ethics committees and/or authorities, and informed consent from patients or their legal representative is a requirement for participation. Names of ethical committees and approval numbers are provided as supplementary information. The study results will be submitted for publication in a peer-reviewed scientific journal and presented at scientific conferences.

TRIAL REGISTRATION NUMBER

NCT02976753, Pre-results.

Budget impact analysis of the use of extended half-life recombinant factor VIII (efmoroctocog alfa) for the treatment of congenital haemophilia a: the Italian National Health System perspective

Background

Congenital haemophilia A (HA) is a rare, inherited, life-long bleeding disorder characterised by prolonged or spontaneous bleeding due to the lack of clotting factor VIII (FVIII) in the body. Treatment for HA involves FVIII replacement therapy and poses great economic burden to National Health Systems and to society. Availability of novel products as extended half-life clotting factor products might change treatment approches and their economic evaluation is essential for an informed treatment choice. Accordingly the objective of the present work is to analyse the economic impact of using efmoroctocog alfa (recombinant factor VIII-Fc fusion protein, rFVIIIFc) for the treatment of children and adults with severe congenital haemophilia A (HA).

Methods

A budget impact analysis was performed to estimate the economic impact of the introduction of rFVIIIFc in the market-mix of products for the treatment of HA. The analysis condidered a 3-year time horizon and the Italian National Health System (INHS) perspective. The model estimated drug costs associated with the treatment of HA in the current scenario - representing the marketplace forecast for the time period of interest assuming that rFVIIFc is not introduced - and a new scenario, assuming that rFVIIIFc is available in the market. The size of the target population was calculated using epidemiological national data. Univariate one-way sensitivity analyses and scenario analyses were performed.

Results

Overall 3-year costs of treating the HA population in the current scenario were 555,277,691 Euro for the INHS. With the introduction of rFVIIIFc, the costs were reduced to 541,897,466 Euro suggesting potential savings to the INHS of 13,380,255 Euro. Results were consistent at variation of most of the model’s parameters; only in case of lower dosage of conventional products and higher dosage of rFVIIIFc, costs for the INHS increased, in both cases, of about 20 million Euro.

Conclusions

The use of rFVIIIFc for the treatment of HA has been recently approved by the Italian Medicines Agency (AIFA) and this is the first study estimating the financial impact of this new therapeutic alternative in the Italian context. The analysis suggests that rFVIIIFc use does not result in higher expenditure for the INHS.

Cost-utility analysis of life-long prophylaxis with recombinant factor VIIIFc vs recombinant factor VIII for the management of severe hemophilia A in Sweden

AIMS

Prophylaxis with recombinant factor VIII (rFVIII) is the standard of care for severe hemophilia A in Sweden. The need for frequent injections with existing rFVIII products may, however, result in poor adherence to prophylaxis, leading to increased bleeding and long-term joint damage. Recombinant FVIIIFc (rFVIIIFc) is an extended half-life fusion protein which can offer prolonged protection and reduced dosing frequency. The objective of this study was to evaluate the cost-utility of prophylaxis with rFVIIIFc in severe hemophilia A from the perspective of the Swedish health system.

METHODS

A Markov model was built to estimate lifetime costs and benefits of prophylaxis with rFVIIIFc vs rFVIII products. Clinical outcomes were represented by annualized bleeding rate (ABR) and quality of life via disutility applied to bleeding events and injection frequency. Costs included the cost of FVIII for routine prophylaxis and bleed resolution. The pooled comparator was costed by weighting the cost of individual products by their market share.

RESULTS

In the base case, rFVIIIFc was dominant vs the pooled comparator. Savings of SEK 9.0 million per patient resulted from lower factor consumption for prophylaxis and bleed resolution. Fewer bleeds and reduced injection frequency yielded an estimated 0.59 quality-adjusted life years (QALYs). Results were sensitive to drug dosage and robust to variation in other parameters. Probabilistic sensitivity analysis suggested a greater than 85% probability of rFVIIIFc being cost-effective at a willingness-to-pay threshold of 500,000 SEK/QALY.

LIMITATIONS

Due to unavailibilty of patient-level data, treatment benefit was based on a non-adjusted indirect comparison. Dosing and treatment outcomes were assumed to persist over the model duration in the absence of long-term outcome data.

CONCLUSION

The results suggest that rFVIIIFc may be a cost-effective option for hemophilia A prophylaxis, generating greater quality of life and reduced costs for the Swedish payer compared to more frequently administered rFVIII alternatives.

The impact of extended half-life versus conventional factor product on hemophilia caregiver burden

INTRODUCTION

Extended half-life factor products have reduced annualized bleeding rates in hemophilia patients. The impact of extended half-life versus conventional factor products on hemophilia caregiver burden has not been investigated. This study aimed to evaluate caregiver burden in extended half-life versus conventional factor products for hemophilia A and B.

METHODS

This cross-sectional web-based study of caregivers of people with hemophilia A or B was recruited from a panel research company and by word of mouth. Participants completed the Hemophilia Caregiver Impact measure, the PedsQL Family Impact Module (PedsQL), and the Work Productivity and Activity Impairment Questionnaire (WPAI). We also collected demographic, insurance coverage, and medical information related to the hemophilia patient(s). Burden differences were assessed using linear regression and matched cohort analyses.

RESULTS

The sample (n = 448) included 49 people who were caring for people on extended half-life factor products. Worse caregiver burden was associated with more infusions per week and more bleeds in the past 6 months. Regression analyses suggested that caring for someone who is on a extended half-life factor product is associated with lower emotional impact (β = - 0.11, p < 0.05, Adjusted R² = 0.06), and shows a trend association with lower practical impact (β = - 0.09, p < 0.10, Adjusted R² = 0.05). The matched cohort analysis also revealed that people on extended half-life factor product had lower Emotional Impact and Practical Impact scores (t = - 2.95 and - 2.94, respectively, p < 0.05 in both cases). No differences were detected on the PedsQL or the WPAI.

CONCLUSION

The reduced required frequency of factor product infusions of extended half-life factor products appears to reduce the emotional distress and practical burden of caregiving. Future work should evaluate the longitudinal impact.