The socioeconomic burden of patients affected by hemophilia with inhibitors

Rapid recognition and optimal management of hemophilia in the emergency department: A quality improvement project

Objectives

This study aimed to assess the effectiveness of a continuous quality improvement initiative at the University of Florida Health Physicians practice in reducing the time to administer factor replacement therapy (FRT) for hemophilia patients presenting with bleeding in the emergency department (ED).

Methods

The study, a quasi-experimental, interventional design, was conducted between January 2020 and January 2023. The intervention, implemented in September 2021, involved training ED physicians, creating a specialized medication order set within the electronic health record (EHR), and a rapid triage system. The effectiveness was measured by comparing the time from ED arrival to factor administration before and after the intervention and benchmarking it against the National Bleeding Disorders Foundation's Medical and Scientific Advisory Council (MASAC)-recommended 1-hour timeline for factor administration. An interrupted time series (ITS) analysis with a generalized least squares model assessed the intervention's impact.

Results

A total of 43 ED visits (22 pre-intervention and 21 post-intervention) were recorded. Post-intervention, the average time from ED arrival to factor administration decreased from 5.63 to 3.15 hours. There was no significant increase (27% vs. 29%) in the patients receiving factor within 1-hour of ED arrival. The ITS analysis predicted a 20-hour reduction in the average quarterly time to administer factor by the end of the study, an 84% decrease.

Conclusions

The quality improvement program decreased the time to administer FRT for patients with hemophilia in the ED. However, the majority of patients did not achieve the 1-hour MASAC-recommended timeline for factor administration after ED arrival.

Clinical and economic burden of immune tolerance induction in entire patients with hemophilia A: Insights from a real-world Korean setting

INTRODUCTION

The most notable challenge facing hemophilia A treatment is the development of inhibitors against factor VIII, resulting in increased clinical and socioeconomic burdens due to the need for expensive bypassing agents (BPAs). Although immune tolerance induction (ITI) is currently the primary approach for inhibiting and reducing the inhibitors, the lengthy duration of ITI necessitates the continued use of BPA to manage bleeding episodes. In this study, we aimed to obtain real-world evidence on the clinical and economic aspects and associated burdens experienced by patients with hemophilia A with inhibitors undergoing ITI in Korea.

METHODS

Claims data from January 1, 2007, to December 31, 2020, were used in this study. The study cohort comprised patients with hemophilia A undergoing ITI, who were categorized into three groups: successful, failed, or continuation of ITI. We evaluated clinical and economic burdens, including monthly healthcare visits, medication costs, and total medical expenses.

RESULTS

The study involved 33 cases of ITI across 32 patients. Excluding seven continuation cases where success could not be determined at the observation point, the estimated success rate of ITI was 80.8 %. The median duration of ITI for all patients was 25.7 months. While no significant disparities were noted in the ITI duration between successful and unsuccessful cases (24.51 vs. 25.66 months), substantial discrepancies were observed in the duration of BPA usage (11.10 vs. 25.66 months) and the number of prescribed BPAs (1.79 vs. 2.97).

CONCLUSION

Successful ITI reduced both clinical and economic burdens, resulting in decreased monthly medication expenses and overall medical costs.

In Utero Cell Treatment of Hemophilia A Mice via Human Amniotic Fluid Mesenchymal Stromal Cell Engraftment

Hemophilia is a genetic disorder linked to the sex chromosomes, resulting in impaired blood clotting due to insufficient intrinsic coagulation factors. There are approximately one million individuals worldwide with hemophilia, with hemophilia A being the most prevalent form. The current treatment for hemophilia A involves the administration of clotting factor VIII (FVIII) through regular and costly injections, which only provide temporary relief and pose inconveniences to patients. In utero transplantation (IUT) is an innovative method for addressing genetic disorders, taking advantage of the underdeveloped immune system of the fetus. This allows mesenchymal stromal cells to play a role in fetal development and potentially correct genetic abnormalities. The objective of this study was to assess the potential recovery of coagulation disorders in FVIII knockout hemophilia A mice through the administration of human amniotic fluid mesenchymal stromal cells (hAFMSCs) via IUT at the D14.5 fetal stage. The findings revealed that the transplanted human cells exhibited fusion with the recipient liver, with a ratio of approximately one human cell per 10,000 mouse cells and produced human FVIII protein in the livers of IUT-treated mice. Hemophilia A pups born to IUT recipients demonstrated substantial improvement in their coagulation issues from birth throughout the growth period of up to 12 weeks of age. Moreover, FVIII activity reached its peak at 6 weeks of age, while the levels of FVIII inhibitors remained relatively low during the 12-week testing period in mice with hemophilia. In conclusion, the results indicated that prenatal intrahepatic therapy using hAFMSCs has the potential to improve clotting issues in FVIII knockout mice, suggesting it as a potential clinical treatment for individuals with hemophilia A.

A review of the rationale for gene therapy for hemophilia A with inhibitors: one-shot tolerance and treatment?

The therapeutic landscape for people living with hemophilia A (PwHA) has changed dramatically in recent years, but many clinical challenges remain, including the development of inhibitory antibodies directed against factor VIII (FVIII) that occur in approximately 30% of people with severe hemophilia A. Emicizumab, an FVIII mimetic bispecific monoclonal antibody, provides safe and effective bleeding prophylaxis for many PwHA, but clinicians still explore therapeutic strategies that result in immunologic tolerance to FVIII to enable effective treatment with FVIII for problematic bleeding events. This immune tolerance induction (ITI) to FVIII is typically accomplished through repeated long-term exposure to FVIII using a variety of protocols. Meanwhile, gene therapy has recently emerged as a novel ITI option that provides an intrinsic, consistent source of FVIII. As gene therapy and other therapies now expand therapeutic options for PwHA, we review the persistent unmet medical needs with respect to FVIII inhibitors and effective ITI in PwHA, the immunology of FVIII tolerization, the latest research on tolerization strategies, and the role of liver-directed gene therapy to mediate FVIII ITI.

Efficacy, safety and cost of emicizumab prophylaxis in haemophilia A patients with inhibitors: A nationwide observational study in Taiwan

INTRODUCTION

Emicizumab mimicking the cofactor function of activated factor VIII (FVIII) restores haemostasis.

METHODS

This nationwide observational study aimed to retrospectively investigate efficacy, safety, and cost in 1 year before and up to 3 years after emicizumab prophylaxis for haemophilia A (HA) patients with FVIII inhibitors.

RESULTS AND DISCUSSION

A total of 39 severe HA patients with a median age of 23.0 years were enrolled. The median historical peak FVIII inhibitor titre was 174.2 BU/mL with an interquartile range of 56.5-578.8 BU/mL. The median annualized bleeding rate reduced from 24 to 0 events in the first year after emicizumab prophylaxis (p < .01) and sustained in the second and third years. The median annualized joint bleeding rate reduced to 0 and maintained up to 3 years (p < .01). Twenty-seven patients (69.2%) had target joints before emicizumab prophylaxis and only seven patients (17.9%) of them had target joints after prophylaxis. Medical costs, including cost of haemostatic therapy, frequency of outpatient department visits, emergency room visits and hospital admission, were significantly reduced after emicizumab prophylaxis (p < .01). FVIII inhibitor titre decreased after emicizumab prophylaxis. Overall, three (7.7%) patients experienced 202 grade 1 drug-related adverse events after emicizumab prophylaxis. No serious adverse events were reported during emicizumab prophylaxis period. The adherence to emicizumab prophylaxis was 100% up to 3 years.

CONCLUSIONS

HA patients with FVIII inhibitors treated with emicizumab prophylaxis resulted in a significant reduction in treated bleeds and associated costs. No new safety events were observed.

Characteristics of FXa-storing platelets in hemophilia B mice and the influence of alcohol on the platelets

Platelet-stored activated blood coagulation factor X (FXa) has great potential in the gene therapy of hemophilia B (HB). However, we still need to understand more about the properties of FXa-storing platelets and how dietary factors affect them. We created transgenic mice called 2bFXa-HB, which had stable expression and storage of FXa in their platelets, resulting in the alleviation of the bleeding disorder in these mice. Even after inducing anti-factor IX (FIX) inhibitors in 2bFXa-HB mice, the hemorrhage phenotype could still be rescued by the expression of FXa. The activation capacity of 2bFXa-HB platelets remained unchanged, and there were no signs of elevated thrombotic risk in these mice. In an acute alcohol exposure mouse model, a single administration of alcohol reduced both the number of platelets and their activation capacity, as well as impaired coagulation function. However, it did not increase the markers of thrombotic risk in either 2bFXa-HB or HB mice. These results suggest that FXa storage in platelets is safe and effective for treatment of HB, but alcohol could impair the therapeutic effect of FXa-containing platelets.

A potent anticoagulant hybrid of snake venom derived FIX-binding protein and anti-factor IX RNA aptamer: Assessed by in-silico and electrochemical analyses

Anticoagulant therapies are crucial in the management of surgical complications as well as the prophylaxis of thrombosis. Many studies are being conducted on the Habu snake-venom anticoagulant, FIX-binding protein (FIX-Bp), for its greater potency and strong affinity to FIX clotting factor. On the other hand, the capacity to promptly reverse such acute anticoagulation is equally important. Combining a reversible anticoagulant with FIX-Bp may be advantageous in maintaining the balance between adequate anticoagulation and repealing when necessary. In this study, authors integrated FIX-Bp and RNA aptamer-based anticoagulants into a single target, FIX clotting factor, in order to achieve a robust anticoagulant effect. An in-silico and electrochemical approach were used to investigate the combination of FIX-Bp and RNA aptamers as a bivalent anticoagulant and to verify the competing or predominant binding sites of each anticoagulant. The in-silico analysis discovered that both the venom- and aptamer-anticoagulant had a strong affinity for the FIX protein at the Gla-domain and EGF-1 domain by holding 9 conventional hydrogen bonds with the binding energy of -34.859 kcal/mol. The electrochemical technique verified that both anticoagulants had different binding sites. The impedance load upon RNA aptamer binding to FIX protein was 14 %, whereas the addition of FIX-Bp caused a significant impedance rise of 37 %. This indicates that the addition of aptamers prior to FIX-Bp is a promising strategy for the conception of a hybrid anticoagulant.

Economic Evaluation of Immune Tolerance Induction in Children With Severe Hemophilia A and High-Responding Inhibitors: A Cost-Effectiveness Analysis of Prophylaxis With Emicizumab

OBJECTIVE

This study aimed to measure the cost-effectiveness of prophylaxis with emicizumab in PsHAhri on ITI in Brazil.

METHODS

A cost-effectiveness modeling analysis was used to estimate the costs per PsHAhri on ITI and the number of prevented bleedings from undertaking one intervention (prophylaxis with BpA) over another (prophylaxis with emicizumab), based on the Brazilian Ministry of Health perspective. Costs of ITI with recombinant FVIII, prophylaxis with BpA or emicizumab, and treated bleeding episodes with BpA costs were evaluated for PsHAhri who had ITI success or failure. This study was conducted with the perspective of the Brazilian Ministry of Health (payer).

RESULTS

During ITI, prophylaxis with BpA cost US $924 666/PsHAhri/ITI, whereas prophylaxis with emicizumab cost US $488 785/PsHAhri/ITI. During ITI, there was an average of 9.32 bleeding episodes/PsHAhri/ITI when BpA were used as prophylaxis and 0.67 bleeding/PsHAhri/ITI when emicizumab was used. By univariate deterministic sensitivity analysis, emicizumab remained dominant whichever variable was modified.

CONCLUSION

In this study, prophylaxis with emicizumab during ITI is a dominant option compared with prophylaxis with BpA during ITI.

Management of children with hemophilia A on emicizumab who need surgery

The introduction of emicizumab into the treatment regime of persons with hemophilia A has dramatically reduced frequency of bleeding in patients with and without inhibitors. However, in children with Hemophilia A (CwHA) who require surgical or other invasive procedures, additional treatment with factor replacement or other hemostatic agents may still be needed to prevent intraoperative or postoperative bleeding. This review will look at the reported outcomes in CwHA on emicizumab who have had surgery and propose recommendations for the best perioperative management of major and minor procedures.

Advances in Hemophilia A Management

Hemophilia A is an inherited insufficiency of Factor VIII (FVIII), one of the critical clotting factors. The gold standard for the management of moderate-to-severe hemophilia A is prophylaxis using regular replacement therapy with clotting factor concentrates. Compared with conventional treatment, extended half-life products reduce the burden of frequent factor replacement injections. Of note, up to 30% of patients with hemophilia A receiving prophylactic factor infusions develop "inhibitors," neutralizing anti-FVIII autoantibodies. Therapeutic options for patients with hemophilia A and inhibitors include the immune tolerance induction (ie, eradication of inhibitors) and the management of acute bleeds with bypassing agents and/or emicizumab. Emicizumab is a biphasic monoclonal antibody mimicking activated FVIII, approved for patients with hemophilia A with/without inhibitors. Gene therapy is an emerging therapy for hemophilia A, essentially curing patients with hemophilia A or transforming them to a milder phenotype by establishing continuous endogenous expression of FVIII after one-time treatment.

Research on the Impact of Home Nursing Based on Intelligent Medical Internet of Things on the Quality of Life of Patients with Hemophilia

The purpose of this paper is to study the feasibility and economic benefits of intelligent medical Internet of Things (IOT) systems for improving the quality of life of hemophilia patients, thereby reducing the risk of teratogenicity and disability for patients. This article selects 60 severe hemophilia patients who were followed up in our hospital from 2018 to 2019 as the research object. In the intelligent medical system, the Gaussian mixture model discretization algorithm is used to preprocess patient data collection. The observation group uses the intelligent medical system to implement home nursing for the patients, and the control group uses ordinary home nursing. This paper evaluates the quality of life of the two groups of patients 6 months after the intervention, including self-care ability, transfer function, and home nursing cognitive ability. The research results show that the home nursing based on smart medical IOT proposed in this paper is feasible and effective for improving the quality of life of patients. It can effectively improve the patient's self-care ability and joint functions and has important reference value for the development of intelligent medical IOT equipment.

Genetic variants at the chromosomal region 2q21.3 underlying inhibitor development in patients with severe haemophilia A

Introduction

Inhibitor development affects about 30% of patients with severe haemophilia A (HA) and results from different environmental and genetic risk factors. Previously, we identified the missense variant rs3754689 in the LCT gene linked with this predisposition. Since rs3754689 variant is benign and is located in a conserved haplotype region, we hypothesized that the association signal captured by this variant is located in coinherited, neighbouring genes.

Aim

To identify novel genetic risk factors associated with inhibitor development in coding regions of R3HDM1, UBXN4, CXCR4, MCM6, DARS and miR128‐1 genes.

Methods

Targeted sequencing was performed in 246 severe HA patients (72 with and 174 without inhibitor): 181 previously and 65 newly enrolled.

Results

Forty‐one common and 152 rare variants passed the quality control. Logistic regression analysis of common variants identified rs3754689 and four additional variants (.011 < P < .047; FDR ranging .2‐.38). Logistic regression analysis performed only in the 220 Italian patients showed similar results (.004 < P < .05; FDR ranging .12‐.22). Three of these variants (rs3213892 and rs3816155 in the LCT intron 13 and rs961360 in the R3HDM1 intron10‐exon11 junction) may affect the expression of UBXN4 and R3HDM1, respectively. Rare variants did not show association with inhibitor development. Identified variants were not replicated in the multi‐ethnic SIPPET cohort of 230 severe HA patients.

Conclusion

Due to the limited sample size that may be responsible of the high FDR values, we could not confirm with certainty the analysed association. Further evaluation of the expression levels of analysed genes will confirm or not their role in inhibitor development.

The impact of improving haemophilia A management within the Spanish National Healthcare System: a social return on investment analysis

BACKGROUND

Haemophilia A (HA) has been associated with poor health-related quality of life and a large economic burden, accentuated by severity, arthropathy, and inhibitors. To meet global standards of care, the management of HA should align with the principles of care outlined by the World Federation of Haemophilia. The aims of the present study were to establish a set of proposals to improve HA management within the Spanish National Health System (SNHS) and to estimate the impact its hypothetical implementation would generate from a clinical, healthcare, economic, and social perspective.

METHODS

A multidisciplinary group of experts agreed on a set of 15 proposals to improve HA management within the SNHS. Thereafter, a forecast-type Social Return on Investment analysis was carried out to estimate the impact of implementing this set of proposals within the SNHS over a one-year timeframe, in relation to the required investment.

RESULTS

This study estimated that the implementation of the complete set of 15 proposals would require a total investment of 2.34 M€ and have a total impact of 14.60 M€. Accordingly, every euro invested in the complete set of 15 proposals would yield a social return of €6.23 (€3.37 in the worst-case scenario and €9.69 in the best-case scenario) of both tangible and intangible nature in similar proportions (45.71 and 54.29%, respectively).

CONCLUSIONS

These results can be used to inform policy and practice such that interventions that may potentially improve current public health challenges associated with the management of HA may be implemented.

Selective Microvascular Tissue Transfection Using Minicircle DNA for Systemic Delivery of Human Coagulation Factor IX in a Rat Model Using a Therapeutic Flap

BACKGROUND

Gene therapy is a promising treatment for protein deficiency disorders such as hemophilia B. However, low tissue selectivity and efficacy are limitations of systemic vector delivery. The authors hypothesized that selective transfection of rat superficial inferior epigastric artery flaps could provide systemic delivery of coagulation factor IX, preventing the need for systemic vector administration.

METHODS

Minicircle DNA containing green fluorescent protein, firefly luciferase, and human coagulation factor IX was created. Vector constructs were validated by transfecting adipose-derived stromal cells isolated from Wistar rat superficial inferior epigastric artery flaps and evaluating transgene expression by fluorescence microscopy, bioluminescence, and enzyme-linked immunosorbent assay. Minicircle DNA luciferase (10 and 30 μg) was injected into murine (wild-type, C57/BL/6) inguinal fat pads (n = 3) and followed by in vivo bioluminescence imaging for 60 days. Wistar rat superficial inferior epigastric artery flaps were transfected with minicircle DNA human coagulation factor IX (n = 9) with plasma and tissue transgene expression measured by enzyme-linked immunosorbent assay at 2 and 4 weeks.

RESULTS

Transfected adipose-derived stromal cells expressed green fluorescent protein for 30 days, luciferase for 43 days, and human coagulation factor IX (21.9 ± 1.2 ng/ml) for 28 days in vitro. In vivo murine studies demonstrated dose-dependence between minicircle DNA delivery and protein expression. Ex vivo rat superficial inferior epigastric artery flap transfection with minicircle DNA human coagulation factor IX showed systemic transgene expression at 2 (266.6 ± 23.4 ng/ml) and 4 weeks (290.1 ± 17.1 ng/ml) compared to control tissue (p < 0.0001).

CONCLUSIONS

Rat superficial inferior epigastric artery flap transfection using minicircle DNA human coagulation factor IX resulted in systemic transgene detection, suggesting that selective flap or angiosome-based tissue transfection may be explored as a treatment for systemic protein deficiency disorders such as hemophilia B.

Factor-mimetic and rebalancing therapies in hemophilia A and B: the end of factor concentrates?

Hemophilia A (HA) and B are inherited bleeding disorders caused by a deficiency of factor VIII or factor IX, respectively. The current standard of care is the administration of recombinant or purified factor. However, this treatment strategy still results in a high economic and personal burden to patients, which is further exacerbated by the development of inhibitors—alloantibodies to factor. The treatment landscape is changing, with nonfactor therapeutics playing an increasing role in what we consider to be the standard of care. Emicizumab, a bispecific antibody that mimics the function of factor VIIIa, is the first such nonfactor therapy to gain US Food and Drug Administration approval and is rapidly changing the paradigm for HA treatment. Other therapies on the horizon seek to target anticoagulant proteins in the coagulation cascade, thus “rebalancing” a hemorrhagic tendency by introducing a thrombotic tendency. This intricate hemostatic balancing act promises great things for patients in need of more treatment options, but are these other therapies going to replace factor therapy? In light of the many challenges facing these therapies, should they be viewed as a replacement of our current standard of care? This review discusses the background, rationale, and potential of nonfactor therapies as well as the anticipated pitfalls and limitations. This is done in the context of a review of our current understanding of the many aspects of the coagulation system.

Predictors of the outcome of immune tolerance induction in patients with haemophilia A and inhibitors: The Brazilian Immune Tolerance (BrazIT) Study protocol

The development of inhibitors is the main complication of haemophilia A (HA) treatment. Immune tolerance induction (ITI) is the treatment of choice for inhibitor eradication. We describe the methodology of the Brazilian Immune Tolerance Induction (BrazIT) Study, aimed to identify clinical, genetic, and immune biomarkers associated with response to ITI and inhibitor recurrence. This cohort study includes people with HA (PwHA) and inhibitors (a) who require bypassing agents to treat and/or prevent bleeding, and (b) who are at any stage of ITI treatment. Patients are included in each haemophilia treatment centre (HTC). Factor VIII (FVIII) and inhibitor assessments are performed at local laboratories of each HTC. The ITI regimen followed the national protocol of the Brazilian Ministry of Health. All PwHA starts with low-dose ITI (50 IU/kg three times weekly); high-dose regimen (100 IU/kg daily) is used if there is lack of response to the low-dose ITI. Outcomes are classified as total or partial success, and failure. Standardized case report forms with clinical, laboratory, and treatment data are collected from medical files and interviews. Blood samples are collected for genetic and immune biomarkers at the time of inclusion in the study and at the end of ITI. The study is ongoing and, currently, 202/250 (80.8%) PwHA from 15 HTCs have been included. BrazIT Study is the largest cohort of PwHA and inhibitor under treatment with the same ITI regimen reported to date. This study is likely to contribute with novel predictors of ITI response.

Variability of treatment modalities and intensity in patients with severe haemophilia A on prophylaxis: Results from the Italian national registry

BACKGROUND

A shift from a standard to a personalized prophylaxis has been increasingly adopted in patients with severe haemophilia A (SHA). This approach has raised the likelihood of a significant variability in the prophylactic approaches and the relative Factor VIII (FVIII) consumptions. The aim of our study was to assess the treatment variability of SHA patients without inhibitors and on prophylaxis regimen in Italy.

MATERIAL AND METHODS

Data reported in the National Registry of Congenital Coagulopathies (NRCC) were analysed to assess treatment distribution within SHA patients without inhibitors, focussing on FVIII consumption in 2017, associated with prophylaxis regimen. The analysis was stratified based on age groups and Italian regions to describe the variability of FVIII consumption in Italy.

RESULTS

In 2017, the Registry reported the therapeutic plans of 1068 SHA patients without inhibitors on prophylaxis. The mean (95% CI) individual consumption ranges from 123 127 IU (99 736-146 518) in the age group 0-6 years to 345 000 IU (336 000-354 000) in the age group >20 years. A significant FVIII consumption variability was identified within the adult population. Regions with less than 50 patients reported the higher variability in mean FVIII consumption per patient-year within the different age groups. Similar difference in FVIII consumption variability was reported also in the age groups comparing "low," "middle" and "high" patient volume regions.

DISCUSSION

A reliable estimation of FVIII consumption for patients' treatment is necessary to manage and plan the appropriate budget and keep treatment's costs affordable. However, without the implementation of a methodology aiming to assess the overall value produced by these FVIII consumptions, the scenario will keep driven by FVIII consumptions, its costs and the budget available. An effort by haemophilic community, haemophilia treatment centres and institutions is required to develop and share this cultural shift in improving haemophilia management and assessment.

Gut dysbiosis modulates the immune response to factor VIII in murine hemophilia A

The development of neutralizing FVIII antibodies is the most serious complication of hemophilia A treatment. The currently known patient- and treatment-related risk factors for inhibitor development do not accurately predict this adverse event in all patients. The composition of the gut microbiota has been shown to influence immune-mediated diseases at distant anatomical sites (eg, lungs, brain, and joints). We demonstrate that a disrupted gut microbiota can be created in a mouse model of hemophilia A using a broad-spectrum antibiotic. Under controlled conditions, this sustained dysbiosis was associated with an increase in splenic B cells and the development of higher titer, FVIII-specific immunoglobulin G antibodies after FVIII challenge. Splenic and mesenteric lymph node cytokines, T cells, and dendritic cells were unaffected before administration of FVIII. However, the immune transcriptome of both aforementioned secondary lymphoid organs was significantly modified. Short-chain fatty acids (SCFAs), which are immunomodulatory microbial metabolites, were depleted in cecal contents of the dysbiotic mice. Furthermore, supplementation of the drinking water with butyrate, the most immunologically active SCFA, successfully achieved attenuation of the FVIII immune response. Collectively, data from this exploratory study suggest that the composition of the gut microbiota alters the FVIII immune response via the action of specific microbial metabolites on the immune cell transcriptome and that oral supplementation with butyrate effectively reduces the FVIII immune response.

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.

The societal burden of haemophilia A. III - The potential impact of emicizumab on costs of haemophilia A in Australia

INTRODUCTION

Emicizumab is a humanized monoclonal modified IgG4 antibody with bispecific antibody structure bridging Factor IXa and Factor X. Emicizumab has demonstrated efficacy and safety in adults, adolescents and paediatrics with HA, with or without inhibitors to Factor VIII (FVIII). There is currently no evidence that reports on the potential impact of the introduction of emicizumab on the societal costs of haemophilia A (HA). The purpose of this study was to explore the cost impact associated with the introduction of emicizumab on the current societal costs of people with HA (PwHA) in Australia.

METHODS

We conducted an analysis of the impact of emicizumab on societal costs, based on changes in the direct and indirect costs incurred by PwHA. Potential impacts of emicizumab on outcomes in PwHA were modelled based on HAVEN 1, HAVEN 2 and HAVEN 3 studies. We assumed that eligible PwHA commenced use of emicizumab on 1 January 2018. The impact of emicizumab on costs of HA in Australia males was then estimated for the 12-month period to 31 December 2018.

RESULTS

Overall, uptake of emicizumab in its first year of use reduces annual costs associated with moderate/severe HA by AUD$69.197M (62.3%). This reflects 64.2% reduction in the cost of FVIII blood products and 92% reduction in cost of bypassing agents.

CONCLUSION

The cost of emicizumab is likely to offset some or all of the projected reductions in treatment costs. However, we also found 30.7% reduction in non-treatment direct costs (AUD$3.771M) and 19.1% reduction in indirect costs (AUD$2.732M).

The societal burden of haemophilia A. I - A snapshot of haemophilia A in Australia and beyond

INTRODUCTION

Few studies, both in Australia and overseas, have examined the social impacts of living with haemophilia A (HA) or the economic costs associated with the disorder. The purpose of this paper is to examine the epidemiology and societal burden of people with HA (PwHA) in Australia, with a particular focus on men with this disorder.

METHODS

The epidemiology and societal burden of HA in Australia, with a particular focus on men with this disorder, were assessed, using data available in the Australian and international literature and publicly available data.

RESULTS

The mean annual prevalence of HA is approximately 1-2 per 10 000 males. Prophylactic treatment is used in one-quarter (25.1%) of people with moderate HA, and 82.2% of people with severe HA. Within the latter group, 16.1% have inhibitors for Factor VIII, predisposing them to worse morbidity, mortality and quality of life when compared to the non-inhibitor population. Joint pain and joint disease occur commonly in PwHA, with up to 70% of adults with HA experiencing joint problems. HA is associated with poor physical health, and PwHA miss school and work due to bleeding-related events.

CONCLUSION

HA is associated with substantial economic burden; with large differences in costs reported between countries. Overall, HA imposes a significant burden of disease on PwHA, their families and the community at large.

A multicenter, open-label phase 3 study of emicizumab prophylaxis in children with hemophilia A with inhibitors

Emicizumab, a bispecific humanized monoclonal antibody, bridges activated factor IX (FIX) and FX to restore the function of missing activated FVIII in hemophilia A. Emicizumab prophylaxis in children with hemophilia A and FVIII inhibitors was investigated in a phase 3 trial (HAVEN 2). Participants, previously receiving episodic/prophylactic bypassing agents (BPAs), were treated with subcutaneous emicizumab: 1.5 mg/kg weekly (group A), 3 mg/kg every 2 weeks (group B), or 6 mg/kg every 4 weeks (group C). Pharmacokinetics, safety, and efficacy (including an intraindividual comparison of participants from a noninterventional study) were evaluated. Eighty-five participants aged <12 years were enrolled. In group A (n = 65), the annualized rate of treated bleeding events (ABRs) was 0.3 (95% confidence interval [CI], 0.17-0.50), and 77% had no treated bleeding events. Intraindividual comparison of 15 participants who previously took BPA prophylaxis showed that emicizumab prophylaxis reduced the ABR by 99% (95% CI, 97.4-99.4). In groups B (n = 10) and C (n = 10), ABRs were 0.2 (95% CI, 0.03-1.72) and 2.2 (95% CI, 0.69-6.81), respectively. The most frequent adverse events were nasopharyngitis and injection-site reactions; no thrombotic events occurred. Two of 88 participants developed antidrug antibodies (ADAs) with neutralizing potential, that is, associated with decreased emicizumab plasma concentrations: 1 experienced loss of efficacy, and, in the other, ADAs disappeared over time without intervention or breakthrough bleeding. All other participants achieved effective emicizumab plasma concentrations, regardless of the treatment regimen. Emicizumab prophylaxis has been shown to be a highly effective novel medication for children with hemophilia A and inhibitors. This trial was registered at www.clinicaltrials.gov as #NCT02795767.

Prevalence of inhibitors and clinical characteristics in patients with haemophilia in a middle-income Latin American country

INTRODUCTION

Development of inhibitors is the most serious complication in patients with haemophilia (PWH). The prevalence of inhibitors in patients with severe haemophilia A (HA) is approximately 25%-30%. Inhibitor prevalence differs among populations. Some studies report a prevalence of almost twice in Hispanic as compared to Caucasian patients. Most data available, on the prevalence of inhibitors and their predisposing factors, originate from centres in developed countries.

AIM

Establish the prevalence of inhibitors of FVIII and FIX in Mexico.

METHODS

This was an observational, cross-sectional and descriptive study. The records of all patients diagnosed with haemophilia A (HA) or B (HB), with and without inhibitors, were included. Clinical and demographical characteristics of patients with inhibitors were assessed. Statistical analysis was performed using IBM SPSS version 22. The Ethics Committees of the various participating institutions approved this study.

RESULTS

A total of 1455 patients from the 20 participating centres were recruited, from which 1208 (83.02%) had HA and 247 (16.97%) were diagnosed with HB. The presence of inhibitors in severe HA was reported in 93/777(11.96%), and 10/162 (6.17%) in severe HB. Of them, 91.7% exhibited high titres in HA and 100% in HB.

CONCLUSION

In Mexico, the general prevalence of inhibitors varies considerably among centres. This study established a basis of comparison for future development and advances in the treatment and follow-up of patients. These findings also augment our understanding of risk factors related to inhibitor development.

New data from the Italian National Register of Congenital Coagulopathies, 2016 Annual Survey

BACKGROUND

In Italy, the National Register of Congenital Coagulopathies (NRCC) collects epidemiological and therapeutic data from patients affected by haemophilia A (HA), haemophilia B (HB), von Willebrand's disease (vWD) and other rare coagulation disorders. Here we present data from the 2016 annual survey.

MATERIALS AND METHODS

Data are provided by the Italian Haemophilia Centres, on a voluntary basis. Information flows from every Centre to a web-based platform of the Italian Association of Haemophilia Centres, shared with the Italian National Institute of Health, in accordance with current privacy laws. Patients are classified by diagnosis, disease severity, age, gender and treatment-related complications.

RESULTS

In 2016, the total number of patients with congenital coagulopathies in the NRCC was 10,360: 39.8% of these patients had HA, 31.5% had vWD, 8.5% had HB, and 20.2% had less common factor deficiencies. The overall prevalence of HA and HB was 13.9/100,000 males and 3.0/100,000 males, respectively. The overall prevalence of vWD was 5.4/100,000 inhabitants. During 2016, 126 patients had current alloantibodies to factor VIII (FVIII) or factor IX (FIX) and were under treatment with bypassing agents and/or immune tolerance induction. Overall, 388 patients with a history of alloantibodies were recorded in the NRCC of whom 337 with severe HA and 12 with severe HB. Coagulation factor use, evaluated from treatment plans, was approximately 451,000,000 IU of FVIII for HA patients (7.5 IU/inhabitant), and approximately 53,000,000 IU of FIX for HB patients (0.9 IU/inhabitant).

DISCUSSION

The prevalences of HA and HB fall within the ranges reported in more developed countries; the consumption of FVIII and FIX was in line with that of other European countries (France, United Kingdom) and Canada. The NRCC, with its bleeding disorder dataset, is a helpful tool for shaping public health policies, as well as planning clinical and epidemiological research projects.

Mechanistic Insights into Factor VIII Immune Tolerance Induction via Prenatal Cell Therapy in Hemophilia A

Purpose of Review

Prenatal stem cell and gene therapy approaches are amongst the few therapies that can promise the birth of a healthy infant with specific known genetic diseases. This review describes fetal immune cell signaling and its potential influence on donor cell engraftment, and summarizes mechanisms of central T cell tolerance to peripherally-acquired antigen in the context of prenatal therapies for Hemophilia A.

Recent Findings

During early gestation, different subsets of antigen presenting cells take up peripherally-acquired, non-inherited antigens and induce the deletion of antigen-reactive T-cell precursors in the thymus, demonstrating the potential for using prenatal cell and gene therapies to induce central tolerance to FVIII in the context of prenatal diagnosis/therapy of Hemophilia A.

Summary

Prenatal cell and gene therapies are promising approaches to treat several genetic disorders including Hemophilia A and B. Understanding the mechanisms of how FVIII-specific tolerance is achieved during ontogeny could help develop novel therapies for HA and better approaches to overcome FVIII inhibitors.

TCPro: an In Silico Risk Assessment Tool for Biotherapeutic Protein Immunogenicity

Most immune responses to biotherapeutic proteins involve the development of anti-drug antibodies (ADAs). New drugs must undergo immunogenicity assessments to identify potential risks at early stages in the drug development process. This immune response is T cell-dependent. Ex vivo assays that monitor T cell proliferation often are used to assess immunogenicity risk. Such assays can be expensive and time-consuming to carry out. Furthermore, T cell proliferation requires presentation of the immunogenic epitope by major histocompatibility complex class II (MHCII) proteins on antigen-presenting cells. The MHC proteins are the most diverse in the human genome. Thus, obtaining cells from subjects that reflect the distribution of the different MHCII proteins in the human population can be challenging. The allelic frequencies of MHCII proteins differ among subpopulations, and understanding the potential immunogenicity risks would thus require generation of datasets for specific subpopulations involving complex subject recruitment. We developed TCPro, a computational tool that predicts the temporal dynamics of T cell counts in common ex vivo assays for drug immunogenicity. Using TCPro, we can test virtual pools of subjects based on MHCII frequencies and estimate immunogenicity risks for different populations. It also provides rapid and inexpensive initial screens for new biotherapeutics and can be used to determine the potential immunogenicity risk of new sequences introduced while bioengineering proteins. We validated TCPro using an experimental immunogenicity dataset, making predictions on the population-based immunogenicity risk of 15 protein-based biotherapeutics. Immunogenicity rankings generated using TCPro are consistent with the reported clinical experience with these therapeutics.

The burden of bleeds and other clinical determinants on caregivers of children with haemophilia (the BBC Study)

INTRODUCTION

Treatment burden for the people with haemophilia has been documented, as has the burden of caring for a child with a common chronic disease such as asthma or diabetes. However, there remains a paucity of data about caregiver burden in haemophilia.

AIMS

The aim of this study was to evaluate the impact of bleeding on caregivers of children with haemophilia. Caregiver burden was stratified by the clinical status of their child.

METHODS

A multinational, non-interventional study of caregivers of children with severe or moderate haemophilia, using the HEMOCABquestionnaire to evaluate caregiver burden.

RESULTS

A total of 144 caregivers from seven EU countries participated in the study. Differences in caregiver burden were identified based on the clinical situation of the child. Greater burden was seen in caregivers of children who experienced joint bleeding in the preceding 12 months, or had target joints or reduced range of motion in most domains of the HEMOCAB. Caring for a child with a current inhibitor also caused significantly higher burden for caregivers when compared to caring for a child with tolerized inhibitor or without inhibitor. Caregivers of children with chronic pain reported significantly higher burden in all domains of the HEMOCAB except for "interaction with the father."

CONCLUSION

Caregiver burden can be affected by the child's haemophilia status, particularly if joint health is impacted (eg bleeds, decreased mobility) or if the child suffers from chronic pain which was moderately correlated with joint bleeds.