EQOFIX: a combined economic and quality‐of‐life study of hemophilia B treatments in France

International Society on Thrombosis and Haemostasis clinical practice guideline for treatment of congenital hemophilia A and B based on the Grading of Recommendations Assessment, Development, and Evaluation methodology

BACKGROUND

Hemophilia is a rare congenital bleeding disorder that results from complete or partial deficiency of blood coagulation factor (F)VIII (hemophilia A) or FIX (hemophilia B) due to pathogenic variants in their coding genes. Hemophilia requires complex management. To date, there is no evidence-based clinical practice guideline on hemophilia treatment based on the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach.

OBJECTIVES

This evidence-based clinical practice guideline from the International Society on Thrombosis and Haemostasis aims to provide an overview of evidence and support patients, caregivers, hematologists, pediatricians, other clinicians, researchers, and stakeholders in treatment decisions about congenital hemophilia A and B.

METHODS

The International Society on Thrombosis and Haemostasis formed a multidisciplinary guideline panel of physicians and patients with global representation, balanced to minimize potential bias from conflicts of interest. The panel prioritized a set of clinical questions and outcomes according to their importance for clinicians and patients. A methodological team supported the guideline development process, including searching for evidence and performing systematic reviews. The GRADE approach was used, including GRADE Evidence to Decision frameworks. The recommendations were subject to public comment.

RESULTS

The panel selected 13 questions, of which 11 addressed the treatment of hemophilia A and 2 the treatment of hemophilia B. Specifically, the panel addressed questions on prophylactic and episodic treatment with FVIII concentrates, bypassing agents, and nonfactor therapy (emicizumab) for hemophilia A (with and without inhibitors) as well as immune tolerance induction for hemophilia A. For hemophilia B, the panel addressed questions on prophylactic and episodic treatment of bleeding events with FIX concentrates. Agreement was reached for all 13 recommendations, of which 7 (54%) were based on evidence from randomized clinical trials, 3 (23%) on observational studies, and 3 (23%) on indirect comparisons.

CONCLUSION

Strong recommendations were issued for prophylactic over episodic treatment for severe and moderately severe hemophilia A and B. Only conditional recommendations were issued for the remaining questions. Future research should focus on direct treatment comparisons and the treatment of hemophilia B with and without inhibitors. Future updates of this guideline will provide an updated evidence synthesis on the current questions and focus on new FVIII and FIX concentrates, novel nonfactor therapies, and gene therapy for severe and nonsevere hemophilia A and B.

Knowledge gaps in health-related quality of life research performed in children with bleeding disorders - A scoping review

INTRODUCTION

Bleeding disorders (BDs) may influence health-related quality of life (HRQoL) in children and caregivers. Measuring HRQoL gives insight into domains requiring support and provides an opportunity to evaluate the effects of novel therapies.

AIM

To gain insight in the current body of literature on HRQoL in children with BDs in order to identify knowledge gaps for research and further development of this field.

METHODS

Scoping review.

RESULTS

We included 53 articles, describing studies mainly performed in Europe and North-America (60.4%) and mostly within the last ten years. Only 32% studies included children <4 years. Almost all studies (47/53, 88.7%) were performed in boys with haemophilia, pooling haemophilia A and B (n = 21) and different disease severities (n = 20). Thirteen different generic and five disease-specific HRQoL-questionnaires were applied; all questionnaires were validated for haemophilia specifically. Six (11,3%) combined generic and disease-specific questionnaires. Self-reports were most frequently applied (40/53, 75.5%), sometimes combined with proxy and/or parent-reports (17/53, 32.1%). Eleven studies used a reference group (20.8%). Statistical analyses mostly consisted of mean and SD (77.4%).

CONCLUSION

HRQoL-research is mainly performed in school-aged boys with haemophilia, treated in developed countries. Pitfalls encountered are the pooling of various BDs, subtypes and severities, as well as the application of multiple generic questionnaires prohibiting comparison of results. More attention is needed for broader study populations including other BDs, young children, feminine bleeding issues and platelet disorders, as well as the use of HRQoL as an effect-measurement tool for medical interventions, and more thorough statistical analysis.

Assessment of the clinical perception, quality of life and satisfaction of patients with severe congenital haemophilia A without inhibitor after 1 year of emicizumab therapy

INTRODUCTION

Since the approval by the EMA of emicizumab for the care of severe haemophilia A without inhibitor, most of the patients of our haemophilia treatment centre started this new treatment. Thanks to the setting of a therapeutic patient education program including three pharmaceutical consultations (PC), we could follow patients' lifestyle evolution.

AIM

The study aimed to assess the perceived clinical evolution, quality of life and treatment satisfaction of patients after 1 year of emicizumab therapy in real-life settings.

METHODS

The study was observational, retrospective and monocentric. Every patient over 18 years old receiving emicizumab from June 2020 and who underwent the 3 PC until March 2022 were included. The clinical evolution was self-estimated by patients with zero-to-six scales before versus 1 year after emicizumab, according to the following parameters: general health state, pain and bleedings (spontaneous or post-traumatic, and patients' identification ability). Patients' quality of life was also estimated with the EQ-5D-3L survey. Their satisfaction, graduated with a zero-to-ten scale, and treatment management were reported during the third PC.

RESULTS

Thirty-eight patients were enrolled. Their general health state improved significantly (p = .0023) with an EQ-5D-3L score at 69.6 (±19.4) out of 100. Although chronic pains remained a persistent issue for 33 (86.8%) patients, their intensity was significantly decreasing after 1 year. Perceived frequency of bleedings was significantly reduced too. On average, the satisfaction of emicizumab therapy was 9.1 (± 1.02) out of 10.

CONCLUSION

After 1 year of emicizumab therapy, the general health state estimated by patients improved, the pain and the perceived frequency of bleedings diminished. Overall, this treatment received a high patients' satisfaction rate.

Occupational integration of adults with severe haemophilia (INTHEMO): A study based on the FranceCoag registry

INTRODUCTION

Health of people with severe haemophilia (PwSH) improves thanks to the advancements in haemophilia care, giving them more opportunities in occupational integration. However, there is little literature on the occupational integration of PwSH.

OBJECTIVES

The main objective of our study was to assess the occupational integration of PwSH and to compare it with that of the general population. The secondary objective was to study the association between individual characteristics (sociodemographic, clinical and psycho-behavioural) and occupational integration of PwSH.

METHODS

A multicentre, non-interventional, cross-sectional study was conducted in 2018-2020 on PwSH, aged over 18 and under 65 years and included in the FranceCoag registry. Measurements included indicators of occupational integration, sociodemographic, clinical and psycho-behavioural characteristics. The indicators of occupational integration were compared with those of the general population, using indirect standardization. The data of the general population were available from the National Institute of Statistics and Economic Studies (INSEE). Determinants of occupational integration were explored using structural equation modelling.

RESULTS

Of 1262 eligible people, 588 were included. PwSH had a lower employment rate than the general population (standardized ratio, .85; 95% CI, .77-.94). There were more PwSH at tertiary education level than expected (standardized ratio, 1.38; 95% CI, 1.17-1.61). HIV infection, poor physical health and mental health concerns were associated with a higher risk of unemployment in PwSH.

CONCLUSION

Employment rate of PwSH is lower than that of the general population despite their higher education level. Target interventions focusing on determinants of difficult occupational integration could be helpful for PwSH.

Medical costs and hospital utilization for hemophilia A and B urban inpatients in China: a national cross-sectional study

Background

Hemophilia care in mainland China has been greatly improved since the establishment of the Hemophilia Treatment Center Collaborative Network of China (HTCCNC), and most of drugs for hemophilia have been covered by basic medical insurance schemes. This study assesses whether medical costs and hospital utilization disparities exist between hemophilia A and hemophilia B urban inpatients in China and, second, whether the prescription of coagulation factor concentrates for hemophilia A and hemophilia B inpatients was optimal, from the third payer perspective.

Methods

We conducted a retrospective nationwide analysis based on a 5% random sample from claims data of China Urban Employees’ Basic Medical Insurance (UEBMI) and Urban Residents’ Basic Medical Insurance (URBMI) schemes from 2010 to 2016. Univariate analysis and multiple regression analysis based on a generalized linear model were conducted.

Result

A total of 487 urban inpatients who had hemophilia were identified, including 407 inpatients with hemophilia A and 80 inpatients with hemophilia B. Total medical cost for hemophilia B inpatients was significantly higher than for hemophilia A inpatients (USD 2912.81 versus USD 1225.60, P < 0.05), and hemophilia B inpatients had a significantly longer length of hospital stay than hemophilia A inpatients (9.00 versus 7.00, P < 0.05). Total medical costs were mostly allocated to coagulation factor products (76.86-86.68%), with coagulation factor cost of hemophilia B significantly higher than hemophilia A (P < 0.05). Both hemophilia cohorts utilized greatest amount of plasma-derived Factor VIII, followed by recombinant Factor VIII and prothrombin complex concentrates.

Conclusions

Patients with hemophilia B experienced significantly higher inpatient cost, coagulation factor cost and longer length of hospital stay than patients with hemophilia A. Our findings revealed the suboptimal use of coagulation factor concentrate drugs and a higher drug cost burden incurred by hemophilia B than hemophilia A inpatients. Our results call for efforts to strengthen drug regulatory management for hemophilia and to optimize medical insurance schemes according to hemophilia types.

Cost-effectiveness of emicizumab vs bypassing agents in the prevention of bleeding episodes in haemophilia A patients with anti-FVIII inhibitors in France

INTRODUCTION

The development of an anti-FVIII inhibitor is the most serious complication of haemophilia A occurring in up to 30% of severe haemophilic patients. The current management of haemophilia A with inhibitor uses bypassing agents (BPA) and represents a significant therapeutic burden together with a limited adherence to prophylactic treatment. Emicizumab is the first monoclonal antibody developed in haemophilia A approved for the prevention of bleeding episodes in patients with anti-FVIII inhibitor.

AIM

The purpose of this study is to evaluate the incremental cost-effectiveness ratio (ICER) of emicizumab versus BPAs.

METHODS

A Markov model was developed over a five-year time horizon to estimate the comparative costs and benefits of the different therapeutic approaches in this rare disease. Model inputs were clinical, including annual bleeding rate and quality of life, and economical including mainly costs of prophylaxis, bleeds and adverse events.

RESULTS

Emicizumab treatment is dominant, ie lest costly and more effective, in the base-case analysis saving 234 191 € for a gain of 0.88 QALY. This is confirmed by both the deterministic and probabilistic sensitivity analyses. The main limit of the study remains the absence of long-term clinical data allowing to relate treatment consumption to clinical benefit, especially in the progression of haemophilic arthropathy.

CONCLUSION

Our results show that emicizumab is a cost-effective treatment allowing to consider an easy to implement prophylactic treatment for haemophilia A patients with anti-FVIII inhibitors.

Enhanced Factor IX Activity following Administration of AAV5-R338L "Padua" Factor IX versus AAV5 WT Human Factor IX in NHPs

Gene therapy for severe hemophilia B is advancing and offers sustained disease amelioration with a single treatment. We have reported the efficacy and safety of AMT-060, an investigational gene therapy comprising an adeno-associated virus serotype 5 capsid encapsidating the codon-optimized wild-type human factor IX (WT hFIX) gene with a liver-specific promoter, in patients with severe hemophilia B. Treatment with 2 × 10¹³ gc/kg AMT-060 showed sustained and durable FIX activity of 3%-13% and a substantial reduction in spontaneous bleeds without T cell-mediated hepatoxicity. To achieve higher FIX activity, we modified AMT-060 to encode the R338L "Padua" FIX variant that has increased specific activity (AMT-061). We report the safety and increased FIX activity of AMT-061 in non-human primates. Animals (n = 3/group) received intravenous AMT-060 (5 × 10¹² gc/kg), AMT-061 (ranging from 5 × 10¹¹ to 9 × 10¹³ gc/kg), or vehicle. Human FIX protein expression, FIX activity, and coagulation markers including D-dimer and thrombin-antithrombin complexes were measured. At equal doses, AMT-060 and AMT-061 resulted in similar human FIX protein expression, but FIX activity was 6.5-fold enhanced using AMT-061. Both vectors show similar safety and transduction profiles. Thus, AMT-061 holds great promise as a more potent FIX replacement gene therapy with a favorable safety profile.

Modern Treatments of Haemophilia: Review of Cost-Effectiveness Analyses and Future Directions

BACKGROUND

Cost is currently one of the most important aspects in haemophilia care. Factor concentrates absorb more than 90% of healthcare direct costs of haemophilia care, and the debate regarding the high cost of haemophilia treatments and their different use across different countries is increasing.

OBJECTIVE

The objective of this study was to review cost-effectiveness analyses conducted on treatment options in haemophilia, focusing on their results and their strengths and limitations; to highlight the possible issues associated with economic evaluations of new treatment options.

METHODS

Electronic searches in PubMed and EMBASE were performed to retrieve papers published between November 2015 and September 2017 to update the previous review of economic evaluations of haemophilia treatments by Drummond et al. Reference lists of included articles and reviews were examined for relevant studies, which were assessed for their quality and their empirical results.

RESULTS

Twenty-six relevant economic analyses were identified; 15 (57.7%) were conducted in patients with haemophilia with inhibitors while 11 (42.3%) involved patients without inhibitors. There were methodological variations among the included studies, and differences in the treatment schemes make a comparative assessment of interventions for patients with haemophilia difficult. Only immune tolerance induction showed consistent results in its cost-saving profile compared with the treatment with bypassing agents.

CONCLUSIONS

Economic evaluations of haemophilia treatments are increasing, but the identification of general cost-effectiveness trends is still difficult in these studies. We are now facing a new era in haemophilia management with a soaring need for high-quality economic evaluations, performed through proactive collaboration between clinical experts, budget holders and health economists.

Gene therapy with adeno-associated virus vector 5-human factor IX in adults with hemophilia B

Gene therapy for hemophilia B aims to ameliorate bleeding risk and provide endogenous factor IX (FIX) activity/synthesis through a single treatment, eliminating the requirement for FIX concentrate. AMT-060 combines an adeno-associated virus-5 (AAV5) vector with a liver-specific promoter driving expression of a codon-optimized wild-type human FIX gene. This multinational, open-label study included 10 adults with hemophilia B (FIX ≤2% of normal) and severe-bleeding phenotype. No participants tested positive for AAV5-neutralizing antibodies using a green-fluorescent protein-based assay, and all 10 were enrolled. A single dose of 5 × 10¹² or 2 × 10¹³ genome copies of AMT-060/kilogram was administered to 5 participants each. In the low-dose cohort, mean endogenous FIX activity increased to 4.4 IU/dL. Annualized FIX use was reduced by 81%, and mean annualized spontaneous bleeding rate (ASBR) decreased from 9.8% to 4.6% (53%). In the higher-dose cohort, mean FIX activity increased to 6.9 IU/dL. Annualized FIX use decreased by 73%, and mean ASBR declined from 3.0 to 0.9 (70%). There was no reduction in traumatic bleeds. FIX activity was stable in both cohorts, and 8 of 9 participants receiving FIX at study entry stopped prophylaxis. Limited, asymptomatic, and transient alanine aminotransferase elevations in the low-dose (n = 1) and higher-dose (n = 2) cohorts were treated with prednisolone. No decrease in FIX activity or capsid-specific T-cell responses were detected during transaminase elevations. A single infusion of AMT-060 had a positive safety profile and resulted in stable and clinically important increases in FIX activity, a marked reduction in spontaneous bleeds and FIX concentrate use, without detectable cellular immune responses against capsids. This trial was registered at www.clinicaltrials.gov as #NCT02396342; EudraCT #2013-005579-42.

Economic Burden of Illness among Persons with Hemophilia B from HUGS Vb: Examining the Association of Severity and Treatment Regimens with Costs and Annual Bleed Rates

OBJECTIVES

To determine US societal burden of illness, including direct and indirect costs and annual bleed rate (ABR), for persons with hemophilia B (HB), a rare and debilitating genetic disorder, and to examine associations of hemophilia severity and treatment regimens with costs and ABR.

METHODS

From 2009 to 2014, the Hemophilia Utilization Group Studies Part Vb collected prospective data from 10 US hemophilia treatment centers. Participants with HB completed initial surveys on sociodemographic characteristics, clinical characteristics, and treatment patterns. During the 2-year follow-up, participants reported bleeding episodes, work absenteeism, and caregiver time quarterly. These data were used to calculate ABR and indirect costs. Direct costs were calculated using 1-year clinical chart records and 2-year dispensing records.

RESULTS

Of the 148 participants, 112 with complete medical records and one or more follow-up survey were included. Total mean annual per-person costs were $85,852 (median $20,160) for mild/moderate HB, $198,733 (median $147,891) for severe HB, and $140,240 (median $63,617) for all participants without inhibitors (P < 0.0001). Mean ABR for participants with severe HB on prophylaxis (5.5 ± 7.9 bleeds/y) was almost half that of those treated episodically. Clotting factor and indirect costs accounted for 85% and 9% of total costs, respectively. Compared with episodic treatment, prophylaxis use was associated with 2.5-fold higher clotting factor costs (P < 0.01), low but significantly more missed parental workdays (P < 0.0001) and clinician (P < 0.001) or nursing visits (P < 0.0001), less part-time employment and unemployment, and lower hospitalizations costs (P = 0.17) and ABR (P < 0.0001).

CONCLUSIONS

HB is associated with high economic burden, primarily because of clotting factor costs. Nevertheless, prophylaxis treatment leads to clinical benefits and may reduce other nonfactor costs.

A national French noninterventional study to assess the long-term safety and efficacy of reformulated nonacog alfa

BACKGROUND

Nonacog alfa, the recombinant Factor IX (F IX) used for the treatment of hemophilia B, was approved in Europe in 1998. A reformulated version was approved for European use in 2007.

STUDY DESIGN AND METHODS

This postmarketing study, as recommended by the risk management plan, was conducted to confirm the safety of reformulated nonacog alfa in a usual care setting in France. This open-label, noninterventional, prospective, longitudinal postmarketing study comprised 19 French hemophilia centers. Patients with hemophilia B receiving reformulated nonacog alfa for prophylaxis or on-demand treatment were followed up on usual care schedule.

RESULTS

A total of 58 subjects were enrolled, of whom 29 (50%) were less than 18 years of age. Hemophilia was severe (baseline F IX activity < 1%) in 47 (81%) patients. All subjects except one were already treated with reformulated nonacog alfa before enrollment. One subject was receiving reformulated nonacog alfa as immune tolerance induction at time of enrollment. At enrollment, treatment regimen was mainly prophylactic in subjects less than 18 years and on-demand in subjects 18 years or older. Median duration of follow-up in the survey was 3.3 (2.3-3.8) years. The median annualized bleeding rate was 3.9 (1.5-5.2) for prophylaxis regimen and 12.2 (3.9-22.1) for on-demand regimen. One subject, a previously untreated patient, developed F IX inhibitors during follow-up. No allergic reaction, no blood cell agglutination, no lack of efficacy or recovery, and no thrombotic events were reported.

CONCLUSION

Reformulated nonacog alfa was shown to be safe in a usual care setting.

New developments in the management of moderate-to-severe hemophilia B

Hemophilia B is an X-linked genetic deficiency of coagulation factor IX (FIX) activity associated with recurrent deep tissue and joint bleeding that may lead to long-term disability. FIX replacement therapy using plasma-derived protein or recombinant protein has significantly reduced bleeding and disability from hemophilia B, particularly when used in a prophylactic fashion. Although modern factor replacement has excellent efficacy and safety, barriers to the broader use of prophylaxis remain, including the need for intravenous (IV) access, frequent dosing, variability in individual pharmacokinetics, and cost. To overcome the requirement for frequent factor dosing, novel forms of recombinant FIX have been developed that possess extended terminal half-lives. Two of these products (FIXFc and rIX-FP) represent fusion proteins with the immunoglobulin G1 (IgG1) Fc domain and albumin, respectively, resulting in proteins that are recycled in vivo by the neonatal Fc receptor. The third product has undergone site-specific PEGylation on the activation peptide of FIX, similarly resulting in a long-lived FIX form. Clinical trials in previously treated hemophilia B patients have demonstrated excellent efficacy and confirmed less-frequent dosing requirements for the extended half-life forms. However, gaps in knowledge remain with regard to the risk of inhibitor formation and allergic reactions in previously untreated patient populations, safety in elderly patients with hemophilia, effects on in vivo FIX distribution, and cost-effectiveness. Additional strategies designed to rebalance hemostasis in hemophilia patients include monoclonal-antibody-mediated inhibition of tissue factor pathway inhibitor activity and siRNA-mediated reduction in antithrombin expression by the liver. Both of these approaches are long acting and potentially involve subcutaneous administration of the drug. In this review, we will discuss the biology of FIX, the evolution of FIX replacement therapy, the emerging FIX products possessing extended half-lives, and novel “rebalancing” approaches to hemophilia therapy.