Prophylaxis versus episodic treatment to prevent joint disease in boys with severe hemophilia

Practical considerations and consensus opinion for children's hospital-based inpatient hemostasis and thrombosis (HAT) consultative services: Communication from the ISTH SSC Subcommittee on Pediatric/Neonatal Thrombosis and Hemostasis

Caring for children and adolescents with disorders of hemostasis and thrombosis (HAT) has become more specialized and requires a unique skill set that many providers are not able to obtain in standard pediatric hematology/oncology/bone marrow transplant fellowship training programs. The influx of numerous therapeutic advances and increasing medical complexity has expanded the need for experienced HAT providers and subspecialty collaboration in the inpatient setting due to the nuances in the management of patients with HAT complications and concerns. While there are data highlighting the benefits of an inpatient hemostasis, thrombosis, and anticoagulation management service in adult hospitals, there are limited pediatric data supporting such programs. In this article, we summarize the current practices of various pediatric institutions in the inpatient management of HAT patients and provide a consensus opinion for the development of a pediatric inpatient HAT service at tertiary care referral centers.

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.

Thromboelastography and thrombin generation assessments for pediatric severe hemophilia A patients are highly variable and not predictive of clinical phenotypes

Background

Severe hemophilia A (SHA) patients vary in severity of bleeding, arthropathy, and requirements for replacement factor VIII (FVIII). Baseline hemostatic activity assays using calibrated automated thrombography (CAT) and thromboelastography (TEG) may offer insights into the physiological basis of clinical heterogeneity.

Objectives

Use CAT and TEG to measure baseline hemostatic activity in a cohort of 30 pediatric SHA patients with available clinical data. Determine effect of contact activation inhibition with corn trypsin inhibitor (CTI). Assess heterogeneity among patients for baseline hemostatic activity and examine correlations between assay results and clinical parameters including FVIII dosing regimen, von Willebrand factor level, and Pettersson arthropathy score.

Methods

SHA blood after FVIII washout was subjected to TEG, and platelet‐rich (PRP) and platelet‐poor plasma was used for CAT assays. Varying concentrations of tissue factor (TF) were used. Statistical analysis examined relationships between assay results, and clinical parameters.

Results

CTI treatment was required to obtain TEG and CAT results representative of baseline hemostatic activity. Weak activity was observed in assays with low TF concentrations (0.5–2 pM), and most but not all samples approached normal activity levels at high TF concentrations (10–20 pM). A significant positive correlation was observed between results of TEG and CAT‐PRP assays. Correlations were not detected between hemostatic assay results and clinical parameters.

Conclusions

In vitro hemostatic assay results of samples containing platelets showed concordance. Assay results were not predictive of FVIII requirements or correlated with other clinical parameters. SHA patient heterogeneity is influenced by factors other than baseline hemostatic activity.

Non‐factor therapies for bleeding disorders: A primer for the general haematologist

Management of patients with severe bleeding disorders, particularly haemophilia A and B, and to a lesser extent, von Willebrand disease, has come on leaps and bounds over the past decade. Until recently, patients relied upon the administration of factor concentrates to prevent or treat bleeding episodes. Factor administration requires intravenous access and, in up to one‐third of patients, leads to the development of neutralising antibodies, or inhibitors, which are associated with more frequent bleeding episodes and higher morbidity. Novel non‐factor therapies may offer a solution to these unmet needs. In this review, we discuss the factor mimetics, particularly emicizumab, and the rebalancing agents, which inhibit antithrombin, tissue factor pathway inhibitor and activated protein C, and novel treatments to enhance von Willebrand factor levels. We review the available trial data, unanswered questions and challenges associated with these new treatment modalities. Finally, we provide practical management algorithms to aid the general haematologist when faced with a patient receiving emicizumab who requires surgery or may develop bleeding.

Osteoporosis in hemophilia: what is its importance in clinical practice?

INTRODUCTION

The relationship between severe hemophilia and osteoporosis has been well established in the literature. However, although the importance of its prevention in order to reduce the risk of bone fractures has been reported, the importance of its treatment in clinical practice has not been well analyzed.

AREAS COVERED

In this paper a review of the available clinical and experimental information on osteoporosis in hemophilia has been performed, to better understand the relationship between hemophilia and osteoporosis. Prevention of osteoporosis in hemophilia should include primary hematological prophylaxis; a diet appropriate in calcium and vitamin D; a regular exercise program that includes aerobics, strength training and balance and flexibility activities; restriction of tobacco and alcohol use; and limitation of the duration of immobilization.

EXPERT OPINION

Prevention of osteoporosis in hemophilic patients is paramount. However, it is noteworthy that there is only one publication on the treatment of osteoporosis in patients with hemophilia. Until further research is done on this topic, the existing recommendations for non-hemophilic patients should be followed. They include the use of antiresorptives (estrogens, selective estrogen receptor modulators, bisphosphonates, denosumab) and anabolic agents (teriparatide, abaloparatide, romosozumab). Further studies on the management of osteoporosis in patients with hemophilia are required.

A single centre, open label, pilot study evaluating the effect of intra-articular hyaluronic acid injection on pain and functionality when injected into the ankle (tibio-talar and sub-talar) joint in patients with haemophilic arthropathy

AIMS

Ankle arthropathy commonly affects persons with haemophilia (PWH). Joint damage causes loss of movement, pain and reduced function. Current treatments are limited. Viscosupplementation has been used to treat other patient groups with joint damage. Viscosupplements serve to augment or act as a substitute for synovial fluid and may ameliorate the effects of cartilage loss by cushioning joints and reducing pain. This study evaluated intra-articular Ostenil Plus™ (HA) for ankle arthropathy in PWH. Reduction in pain was the primary outcome.

METHODS

A single centre open label pilot study. PWH and significant ankle arthropathy, according to MRI scores, were recruited. Participants received intra-articular HA injections at baseline and 6 months. Follow up assessments were completed three-monthly for 1 year. Pain was assessed by the Visual Analogue Scale (VAS). Participant perceptions of overall changes to pain, function and quality of life were sought.

RESULTS

Twenty-four participants were recruited, three withdrew. Twenty-six joints were injected. Twenty participants had severe haemophilia. Mean age 35 years. Participants reported significant reduction in pain over the study. VAS baseline: 5.62; 6 month 3.92; 12-month 3.42, P < .0001. Joint function improved together with ankle HJHS. No change was seen for EQ-5D-5L. Sixteen participants reported reductions in ankle pain and stiffness and greater confidence in undertaking physical activities. No significant adverse reactions were reported.

CONCLUSION

Ostenil Plus™ treatment improves pain, function and patient perception of functional ability in PWH and ankle arthropathy. This study supports the use of HA as a safe treatment in PWH.

The bleeding phenotype in people with nonsevere hemophilia

Detailed information on the onset, frequency, and severity of bleeding in nonsevere hemophilia is limited. We aimed to assess the bleeding phenotype of persons with nonsevere hemophilia and to analyze the association between baseline factor VIII/IX (FVIII/IX) levels and the joint bleeding rate. In the DYNAMO (Dynamic Interplay Between Bleeding Phenotype and Baseline Factor Level in Moderate and Mild Hemophilia A and B) study, an international multicenter cohort, we included males with nonsevere hemophilia (FVIII/IX, 0.02-0.35 IU/mL) aged 12 to 55 years. Information on age at first treated (joint) bleed, annual bleeding rates (ABRs), and annual joint bleeding rates (AJBRs) was collected from the medical files. The association between baseline FVIII/IX levels and the joint bleeding rate was assessed by using a frailty model for recurrent events. In total, 304 persons (70 with moderate hemophilia and 234 with mild hemophilia) were included. The median age was 38 years (interquartile range [IQR], 25-49 years), and the median baseline FVIII/IX level was 0.12 IU/mL (IQR, 0.05-0.21 IU/mL). In total, 245 (81%) persons had experienced at least 1 bleed, and 156 (51%) had experienced at least 1 joint bleed. The median age at first bleed and first joint bleed was 8 and 10 years, respectively. The median ABR and AJBR was 0.2 (IQR, 0.1-0.5) and 0.0 (IQR, 0.0-0.2). From baseline FVIII/IX levels 0.02 to 0.05 IU/mL to >0.25 IU/mL, the median ABR decreased from 0.6 (IQR, 0.2-1.4) to 0.1 (IQR, 0.0-0.2) and the AJBR from 0.2 (IQR, 0.0-0.4) to 0.0 (IQR, 0.0-0.0). Baseline FVIII/IX was inversely associated with the joint bleeding rate (P < .001). Low bleeding rates were observed in persons with nonsevere hemophilia. However, one-half of all adolescents and adults had experienced a joint bleed.

Activated partial thromboplastin time-based clot waveform analysis enables measurement of very low levels of factor IX activity in patients with severe hemophilia B

The precise measurement of very low levels of factor IX activity (FIX:C < 1 IU/dL) is essential for understanding clinical severity and risk of inhibitor development in patients with severe hemophilia B (Pw-SHB). However, such measurement sensitivity has not yet been achieved. We aimed to establish a measurement method using clot waveform analysis (CWA). Residual FIX:C by adding anti-FIX monoclonal antibody, FIX:C by adding recombinant (r)FIX to the commercial Pw-SHB plasmas, and FIX:C in our Pw-SHB were determined by CS-2000i^™/CS-2400^™, followed by analysis of CWA parameters. The presence of anti-FIX antibody in the commercial Pw-SHB plasmas significantly decreased coagulation potential compared to its absence. The addition of rFIX to these innate plasma samples produced significant changes in three parameters upon adding FIX:C at 0.1-1 IU/dL, supporting the presence of trace FIX:C in Pw-SHB. Therefore, appropriate FIX-depleted plasma containing minimum residual FIX:C was chosen from reference curves of FIX:C (0.01-1 IU/dL). Among patients with untreated Pw-SHB, two had FIX:C 0.6-0.7 IU/dL and two had lower than detectable levels using FIX-depleted plasma. One of the latter had detectable trough levels post-rFIX administration. In conclusion, CWA enabled measurement of very low levels of FIX:C using appropriate FIX-deficient plasma.

Efficacy, safety and pharmacokinetics of recombinant human coagulation factor VIII (omfiloctocog alfa) in previously treated Chinese children with severe hemophilia A

INTRODUCTION

Omfiloctocog alfa, the first China-developed recombinant factor VIII (FVIII), demonstrated efficacy and safety of prophylaxis in previously treated patients (PTPs) aged ≥12 years with severe hemophilia A in China.

AIMS

To investigate efficacy, safety and pharmacokinetics (PK) of omfiloctocog alfa in pediatric PTPs with severe hemophilia A in China.

METHODS

PTPs (>50 exposure days [ED] for Chinese patients aged <6 years; >150 EDs for patients aged 6-12 years) were treated with omfiloctocog alfa at 25-50 IU/kg every other day or three times per week for 24 weeks. PK was evaluated after single injection of 50 IU/kg. The primary efficacy endpoint was annualized bleeding rate (ABR).

RESULTS

A total of 69 patients were enrolled (<6 years, n = 35; 6-12 years, n = 34) and mean exposure to omfiloctocog alfa was 78.9 days. Mean half-life was 6.7 and 10.2 h in children < 6 years and 6-12 years, respectively. Estimated mean ABRs of all patients were 4.05 for overall bleeding episodes and 1.38 for spontaneous bleeding episodes. Of 127 bleeding episodes, the success rate was 92.1%. 39.7% patients did not experience any bleeding episodes and the mean weekly dose of FVIII was 109.1 IU/kg for these patients. 83% bleeding episodes were controlled with ≤2 injections. Adverse reactions occurred in 2.9% of the patients. One 2-year-old patient developed inhibitors after 12 EDs and it resolved with omfiloctocog alfa immune tolerance induction.

CONCLUSION

Omfiloctocog alfa was efficacious and well tolerated for the prevention and treatment of bleeding in Chinese pediatric PTPs with severe hemophilia A.

Associated comorbidities, healthcare utilization & mortality in hospitalized patients with haemophilia in the United States: Contemporary nationally representative estimates

INTRODUCTION

Current in-hospital burden and healthcare utilization patterns for persons with haemophilia (PWH) A and B, including both children (ages < 18 years) and adults (ages ≥ 18 years), in the United States (US) are lacking.

AIM

To evaluate healthcare utilization, the prevalence of comorbidities, and mortality in hospitalized paediatric and adult PWH using a contemporary nationally representative cohort.

METHODS

Hospitalizations of PWH either as the primary reason for admission (principal diagnosis) or one of all listed diagnoses were identified using ICD-10 codes from the 2017 Nationwide Inpatient Sample (NIS), the largest publicly available all-payer inpatient discharge database in the US. Sampling weights were applied to generate nationally representative estimates.

RESULTS

The contemporary cohort included 10,555 hospitalizations (paediatrics, 18.3%; adults, 81.7%) among PWH as one-of-all listed diagnoses (n = 1465 as principal diagnosis). Median age (interquartile range) was 46 (24-66) years overall; adults, 54 (35-70) years and paediatric, 4 (1-11). The most common comorbidities in adults were hypertension (33.4%), hyperlipidaemia (23.6%), and diabetes (21.1%). In children, hemarthrosis (11.4%), contusions (9.6%), and central line infections (9.3%) were the most common. The overall mortality rate was 2.3%. Median hospital charges per haemophilia admission were $52,616 ($24,303-$135,814) compared to $26,841 ($12,969-$54,568) for all-cause admissions in NIS.

CONCLUSION

Bleeding and catheter-related infections are the significant reasons for paediatric haemophilia admissions. Adult haemophilia admissions tend to be associated with age-related comorbidities. Costs for haemophilia-related hospitalizations are higher than the national average for all-cause hospitalizations.

Cost-Effectiveness Analysis of Pharmacokinetic-Guided Prophylaxis Versus Standard Prophylaxis in Adults with Severe Hemophilia A in China

Introduction

Multiple studies have demonstrated the effectiveness of pharmacokinetic (PK)-guided individualized prophylaxis with human coagulation factor VIII (FVIII) compared with standard prophylaxis, but no studies have evaluated the economics of PK-guided prophylaxis in China. Hence, we conducted this study to assess the cost-effectiveness of PK-guided prophylaxis with recombinant FVIII (rFVIII) versus standard prophylaxis in Chinese adult patients with severe hemophilia A.

Methods

A discrete event simulation model was developed to simulate 10,000 patients with hemophilia A who received rFVIII treatment over a 1-year time horizon. The standard prophylaxis rFVIII dose was 30 IU/kg by intravenous injection. The PK-guided prophylaxis dosage was adjusted for each patient to maintain FVIII trough level at 1–5 IU/dL. Dosing interval for both approaches was kept fixed at 48 h. The health outcomes included annual joint bleed rate (AJBR) and quality-adjusted life years (QALYs). The model considered the costs of drug. Incremental cost-effectiveness ratio (ICER) was estimated and scenario analysis was performed.

Results

A total of 94.3% of patients receiving PK-guided individualized prophylaxis achieved the goal of maintaining the trough concentration at 1–5 IU/dL compared with 62.7% on standard prophylaxis. AJBR and QALYs gained in PK-guided and standard prophylaxis were 1.527 vs 1.601, and 0.8384 vs 0.8383, respectively. Costs of drug prophylaxis and costs of treatment for bleeding events in PK-guided prophylaxis (148,641.47 USD; 4546.43 USD) were lower than those in standard prophylaxis (159,620.93 USD; 4753.39 USD). An average saving of USD 11,186.47 was obtained by the PK-guided approach. The prophylaxis treatment scenarios were the most influential factors.

Conclusion

PK-guided individualized prophylaxis appeared to be a dominant treatment compared with standard prophylaxis, with slightly higher QALYs but lower total costs.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12325-022-02220-3.

Post-procedural bleeding rate and haemostatic treatment use for dental procedures before and after the implementation of a standardized protocol for people with inherited bleeding disorders

INTRODUCTION

Persons with inherited bleeding disorders are at a substantial risk of bleeding following dental procedures.

AIM

To compare the outcomes and use of haemostatic treatment pre- and post-implementation of a standardized protocol for dental procedures at a Hemophilia Treatment Centre.

METHODS

We conducted a retrospective cohort study of outpatient and inpatient dental procedures and maxillofacial surgeries sustained by people with bleeding disorders treated at a comprehensive Hemophilia Treatment Centre (2013-2020), comparing patients' outcomes before and after the introduction of the protocol in 2018. The protocol, built using a multidisciplinary approach, suggested haemostatic treatment based on the invasiveness of the dental procedure and the proposed anaesthesia. Our primary outcome was the rate of procedural bleeding leading to medical or dental reintervention within 10 days. Secondary outcomes included the use of systemic haemostatic treatment and treatment-related adverse effects.

RESULTS

Overall, 137 dental procedures in 95 patients (median age: 29 years; 78% males; 74% haemophilia, 14% von Willebrand disease, 12% other disorders) were included. Seventeen procedural bleedings were reported (12.4%). Procedural bleeding occurred in 14.8% and 8.9% of patients in the control and intervention groups (p = .304). No major bleeding occurred. Tranexamic acid was used more consistently after protocol implementation (72.8% vs. 89.3%, p = .019), while factor concentrates use decreased (65.4% vs. 44.6%, p = .016), and desmopressin use remained constant (46.4% vs. 32.1%, p = .100). No treatment-related adverse effects were reported.

CONCLUSION

The use of a standardized protocol increased the use of tranexamic acid, with a nonstatistically significant reduction in procedural bleeding rate.

Building the blueprint: Formulating a community-generated national plan for future research in inherited bleeding disorders

Introduction

Decades of inherited bleeding disorders (BD) research transformed severe haemophilia from a childhood killer to a disorder managed across a full lifespan for many in economically developed countries. Health equity, a life unimpaired by disease complications, however, remains unimaginable for most people with an inherited BD (PWIBD).

Aim

The National Hemophilia Foundation (NHF) and American Thrombosis and Hemostasis Network (ATHN) undertook the development of a community‐driven United States (US) National Blueprint for Inherited Bleeding Disorders Research to transform the experience of all PWIBD and those who care for them.

Methods

Extensive community consultations were conducted to identify the issues most important to PWIBD and those who love and care for them. Expert multidisciplinary teams distilled these key areas of need into prioritised research questions, and identified the resources and infrastructure required to pursue them. A summit was held to gather feedback and inform the detailed blueprint.

Results

Community‐prioritised research areas fell into three broad categories: issues common across inherited BDs, those specific to individual disorders, and issues of infrastructure and capacity. NHF State of the Science Research Summit discussions of the research questions derived from the community priorities by six working groups provided important input for the drafting of the research blueprint for the coming decades.

Conclusion

The inherited BD community came together to develop the US National Blueprint for Inherited Bleeding Disorders Research dedicated to transforming the lives of all PWIBD including innovating solutions for the rarest disorders and under‐represented populations.

AOZORA: long-term safety and joint health in paediatric persons with haemophilia A without factor VIII inhibitors receiving emicizumab - protocol for a multicentre, open-label, phase IV clinical study

INTRODUCTION

Persons with haemophilia A (PwHA) commonly experience regular bleeding into joints, which may result in joint damage and complications such as degenerative arthritis. Emicizumab has previously demonstrated efficacy in reducing the occurrence of joint bleeds and target joints, along with having a favourable safety profile; however, data on the long-term effects on joint health are lacking. The AOZORA study will evaluate the long-term safety and joint health of paediatric PwHA without factor (F)VIII inhibitors taking emicizumab; here, we report the details of the study protocol and baseline data.

METHODS AND ANALYSIS

AOZORA is a multicentre, open-label, phase IV clinical study in Japan that aims to enrol approximately 30 PwHA aged <12 years without FVIII inhibitors. The primary endpoints include a long-term safety evaluation of adverse events, laboratory test abnormalities and FVIII inhibitor development; and a long-term joint health assessment using MRI and the Hemophilia Joint Health Score. Exploratory endpoints include characterising participants' physical activities and the number of activity-related bleeds requiring coagulation factor treatment. Currently, 30 participants have been enrolled, including 20 emicizumab-naïve participants and 10 who transferred from HOHOEMI, a previous study in paediatric PwHA.

ETHICS AND DISSEMINATION

The AOZORA study was approved by the Institutional Review Boards of Nara Medical University and the St Marianna University Group. The study will be conducted in compliance with the Declaration of Helsinki, the standards stipulated in paragraph 3 of Article 14 and Article 80-2 of the Pharmaceuticals, Medical Devices and Other Therapeutic Products Act, the Ministerial Ordinance on Good Clinical Practice and the Ministerial Ordinance on Good Post-marketing Study Practice. Data will be published in peer-reviewed journals and presented at Global congresses.

TRIAL REGISTRATION NUMBER

JapicCTI-194701.

SYMPHONY consortium: Orchestrating personalized treatment for patients with bleeding disorders

BACKGROUND

Treatment choices for individual patients with an inborn bleeding disorder are increasingly challenging due to increasing options and rising costs for society. We have initiated an integrated interdisciplinary national research programme.

OBJECTIVES

The SYMPHONY consortium strives to orchestrate personalized treatment in patients with an inborn bleeding disorder, by unravelling the mechanisms behind inter-individual variations of bleeding phenotype.

PATIENTS

The SYMPHONY consortium will investigate patients with an inborn bleeding disorder, both diagnosed and not yet diagnosed.

RESULTS

Research questions are categorized under the themes: 1) Diagnosis; 2) Treatment; and 3) Fundamental research and consist of workpackages addressing specific domains. Importantly, collaborations between patients and talented researchers from different areas of expertise promise to augment the impact of the SYMPHONY consortium, leading to unique interactions and intellectual property.

CONCLUSIONS

SYMPHONY will perform research on all aspects of care, treatment individualization in patients with inborn bleeding disorders as well as diagnostic innovations and results of molecular genetics and cellular model technology with regard to the hemostatic process. We believe that these research investments will lead to health care innovations with long-term clinical and societal impact. This consortium has been made possible by a governmental, competitive grant from the Netherlands Organization for Scientific Research (NWO) within the framework of the NWA-ORC Call grant agreement NWA.1160.18.038.

Risk factors for bleeding in people living with hemophilia A and B treated with regular prophylaxis: A systematic review of the literature

BACKGROUND

Knowledge about the risk for bleeding in patients with hemophilia (PWH) would be relevant for patients, stakeholders, and policy makers.

OBJECTIVES

To perform a systematic review of the literature on risk assessment models (RAMs) and risk factors for bleeding in PWH on regular prophylaxis.

METHODS

We searched Medline, Embase, the Cochrane Central Register of Controlled Trials, and the Cochrane Database of Systematic Reviews from inception through August 2019. In duplicate, reviewers screened the articles for inclusion, extracted data, and assessed the risk for bias using the Quality in Prognostic Studies (QUIPS) tool. A qualitative synthesis of the results was not performed due to high heterogeneity in risk factors, outcomes definition and measurement, and statistical analysis of the results.

RESULTS

From 1843 search results, 10 studies met the inclusion criteria. No RAM for the risk for bleeding in PWH was found. Most studies included only PWH A or both PWH A and B and were conducted in North America or Europe. Only one study had a low risk for bias in all the domains. Eight categories of risk factors were identified. The risk for bleeding was increased when factor levels were lower and in people with a significant history of bleeding or who engaged in physical activities involving contact.

CONCLUSIONS

Our findings suggest that plasma factor levels, history of bleeds, and physical activity should be considered for the derivation analysis when building a RAM for bleeding in PWH, and the role of other risk factors, including antithrombotic treatment and obesity, should be explored.

The Potential Role of Protease Systems in Hemophilic Arthropathy

Haemophilic arthropathy is characterised by joint damage following recurrent joint bleeds frequently observed in patients affected by the clotting disorder haemophilia. Joint bleeds or haemarthroses trigger inflammation in the synovial tissue which promotes damage to the articular cartilage. The plasminogen activation system is integral to fibrinolysis, and urokinase plasminogen activator or uPA in particular is strongly upregulated following haemarthroses. uPA is a serine protease that catalyses the production of plasmin, a broad-spectrum protease that can degrade fibrin as well as proteins of the joint extracellular matrix and cartilage. Both uPA and plasmin are able to proteolytically generate active forms of matrix metalloproteinases (MMPs). The MMPs are a family of >20 proteases that are secreted as inactive proenzymes and are activated extracellularly. MMPs are involved in degradation of all types of collagen and proteoglycans that constitute the extracellular matrix, which provides structural support to articular cartilage. The MMPs have an established role in joint destruction following rheumatoid arthritis (RA). They degrade cartilage and bone, indirectly promoting angiogenesis. MMPs are also implicated in the pathology of osteoarthritis (OA) characterized by degradation of the cartilage matrix that precipitates joint damage and deformity. HA shares a number of overlapping pathological characteristics with RA and OA. Here we discuss how the plasminogen activation system and MMPs might exacerbate joint damage in HA, lending insight into novel possible therapeutic targets to reduce co-morbidity of haemophilia.

Gene therapy - are we ready now?

Introduction

Haemophilia therapy has evolved from rudimentary transfusion‐based approaches to an unprecedented level of innovation with glimmers of functional cure brought by gene therapy. After decades of misfires, gene therapy has normalized factor (F)VIII and factor (F)IX levels in some individuals in the long term. Several clinical programmes testing adeno‐associated viral (AAV) vector gene therapy are approaching completion with imminent regulatory approvals.

Discussion

Phase 3 studies along with multiyear follow‐up in earlier phase investigations raised questions about efficacy as well as short‐ and long‐term safety, prompting a reappraisal of AAV vector gene therapy. Liver toxicities, albeit mostly low‐grade, occur in the first year in at least some individuals in all haemophilia A and B trials and are poorly understood. Extreme variability and unpredictability of outcome, as well as a slow decline in factor expression (seemingly unique to FVIII gene therapy), are vexing because immune responses to AAV vectors preclude repeat dosing, which could increase suboptimal or restore declining expression, while overexpression may result in phenotoxicity. The long‐term safety will need lifelong monitoring because AAV vectors, contrary to conventional wisdom, integrate into chromosomes at the rate that calls for vigilance.

Conclusions

AAV transduction and transgene expression engage the host immune system, cellular DNA processing, transcription and translation machineries in ways that have been only cursorily studied in the clinic. Delineating those mechanisms will be key to finding mitigants and solutions to the remaining problems, and including individuals who cannot avail of gene therapy at this time.

Therapeutic and technological advancements in haemophilia care: Quantum leaps forward

INTRODUCTION

Recent technological innovations in haemophilia have advanced at an astounding pace, including gene therapy programmes and bioengineered molecules for prophylaxis, products that reduce treatment burden through half-life extension, unique mechanisms of action, and subcutaneous administration. Additional technological advancements have emerged that are anticipated to further transform haemophilia care.

AIM

Review new and emerging haemophilia therapies, including replacement and bypassing products, digital applications, utilisation of big data, and personalised medicine.

METHODS

Data were obtained from peer-reviewed presentations/publications, and ongoing studies in haemophilia, ultrasonography, and artificial intelligence (AI).

RESULTS

Available treatments include new recombinant factors VIII (FVIII) and IX (FIX), extended half-life FVIII/IX products, a new FVIIa product for inhibitor patients, and a FVIIIa-mimetic. Several novel therapeutics are in clinical trials, including FVIIIa mimetics and inhibitors of naturally-occurring anticoagulants. Ongoing gene therapy trials suggest that a single vector infusion using an optimised construct can produce factor activity that reduces bleeding to near zero for years. Today, persons with haemophilia (PwH) approach a lifespan comparable to that of the general population, presenting treatment challenges for age-related co-morbidities. Technological innovations have broadened beyond therapeutics to include large database analyses utilising remote data collection with handheld devices, and to tailor AI applications. Current development efforts include patient-performed ultrasonography, algorithms for scan interpretation, and point-of-care haemostatic testing devices.

CONCLUSIONS

We have entered a golden age for haemophilia treatment and care with wide-ranging advancements targeting improved quality of life (QoL). Future-focused efforts by clinical and patient communities may provide equitable access and care for people impacted by haemophilia worldwide.

Longitudinal profiling of anti-factor VIII antibodies in Japanese patients with congenital hemophilia A during factor VIII replacement and immune-tolerance induction therapy

When patients with hemophilia A develop factor VIII (FVIII) inhibitors, FVIII replacement therapy becomes ineffective. Although immune-tolerance induction (ITI) therapy has been used to eradicate inhibitors, treatment is unsuccessful in approximately 30% of cases. However, the mechanism behind treatment failure remains unclarified. We retrospectively examined the longitudinal profiles of immunoglobulin G (IgG) subclasses and/or the inhibitory activities of FVIII in plasma samples from 14 Japanese patients with congenital hemophilia A during hemostatic, FVIII replacement, and/or ITI therapies. In five patients, an increase in IgG4 was observed simultaneously with a decrease in IgG1 when the patient had a history of relatively high FVIII inhibitor titers, reflecting an apparent change in humoral immunity. In addition, we examined the reactivity and specificity of the patients' anti-FVIII IgG1 and IgG4 to FVIII domains by immunoblotting. Under our experimental conditions, plasma from three patients with historically higher inhibitor titers appeared to have high titers of antibodies against the A2-a2 domain, which did not necessarily correlate with ITI failure. These observations may improve scientific understanding of the immune response to infused FVIII in patients with hemophilia A.

Liver gene therapy with intein-mediated F8 trans-splicing corrects mouse haemophilia A

Liver gene therapy with adeno‐associated viral (AAV) vectors is under clinical investigation for haemophilia A (HemA), the most common inherited X‐linked bleeding disorder. Major limitations are the large size of the F8 transgene, which makes packaging in a single AAV vector a challenge, as well as the development of circulating anti‐F8 antibodies which neutralise F8 activity. Taking advantage of split‐intein‐mediated protein trans‐splicing, we divided the coding sequence of the large and highly secreted F8‐N6 variant in two separate AAV‐intein vectors whose co‐administration to HemA mice results in the expression of therapeutic levels of F8 over time. This occurred without eliciting circulating anti‐F8 antibodies unlike animals treated with the single oversized AAV‐F8 vector under clinical development. Therefore, liver gene therapy with AAV‐F8‐N6 intein should be considered as a potential therapeutic strategy for HemA.

BAFF rs9514828 gene polymorphism and the risk of the development of inhibitors in children with severe haemophilia A

INTRODUCTION

Haemophilia A (HA) is an x-linked recessive disease due to deficiency of coagulation factor VIII (FVIII). The development of neutralizing antibodies (inhibitors) against infused FVIII is a major concern. B cell activating factor (BAFF) has been implicated in several autoimmune diseases.

AIM

We aimed to evaluate the possible association of BAFF rs9514828 gene polymorphism and the risk of the development of FVIII inhibitor in children with severe HA.

METHODS

This cohort study was carried out on 100 newly diagnosed boys with severe HA who were never treated before with FVIII concentrate. Assessment of serum levels of BAFF and BAFF rs9514828 genotyping at first diagnosis was performed and the patients were followed up for the completion of a total of 50 exposure days or the development of inhibitors whichever occurred first. The patients were divided as positive or negative according to the presence or absence of inhibitors.

RESULTS

The risk allele for BAFF rs9514828 (T) was significantly more frequent in the inhibitor positive patients than the inhibitor negative patients (P = .003). In addition, CT+TT genotypes were associated with increased risk of FVIII inhibitor development. Receiver operating characteristics (ROC) analysis showed that BAFF levels could predict the development of FVIII inhibitors at a cut-off value of ≥ .92 with a sensitivity of 85.9% and a specificity of 80.2%.

CONCLUSION

BAFF rs9514828 gene polymorphism could be independent risk factor and elevated BAFF levels might be useful prognostic marker for the development of FVIII inhibitor in newly diagnosed children with severe HA.

Joint status of patients with nonsevere hemophilia A

BACKGROUND

Joint bleeding in hemophilia may eventually lead to joint damage. In nonsevere hemophilia, joint bleeds occur infrequently. Currently, knowledge on the joint status of patients with nonsevere hemophilia using objective imaging is limited.

OBJECTIVE

To investigate the joint status in patients with nonsevere hemophilia A.

METHODS

This cross-sectional study included patients with nonsevere hemophilia A aged 24-55 years. Joint status was assessed by magnetic resonance imaging (MRI) of the elbows, knees, and ankles and International Prophylaxis Study Group (IPSG) scores were calculated. Lifetime joint bleeding history was collected from medical files. The contribution of factors to joint outcome was explored using multivariable linear regression analysis.

RESULTS

In total, 51 patients were included, of whom 19 (37%) had moderate and 32 (63%) had mild hemophilia. Patients had a median age of 43 years (interquartile range [IQR] 32-50), a median factor VIII activity of 10 IU/dl (IQR 4-16) and a median annual joint bleeding rate (AJBR) of 0.0 (IQR 0.0-0.2). Soft-tissue changes (IPSG subscore > 0) in the elbows, knees, and ankles were present in 19%, 71%, and 71% of patients, respectively. Osteochondral changes (IPSG subscore > 0) in the elbows, knees, and ankles were present in 0%, 20%, and 35% of patients, respectively. In 14% of bleed-free joints, hemosiderin depositions were observed. Age and AJBRs were most strongly associated with the IPSG score.

CONCLUSION

This study demonstrates that a substantial proportion of adults with nonsevere hemophilia has joint changes on MRI despite low joint bleeding rates.

Impact of novel hemophilia therapies around the world

Hemophilia A and B are hereditary bleeding disorders, characterized by factor VIII or IX deficiencies, respectively. For many decades, prophylaxis with coagulation factor concentrates (replacement therapy) was the standard‐of‐care approach in hemophilia. Since the 1950s, when prophylaxis started, factor concentrates have been improved with virus inactivation and molecule modification to extend its half‐life. The past years have brought an intense revolution in hemophilia care, with the development of nonfactor therapy and gene therapy. Emicizumab is the first and only nonreplacement agent to be licensed for prophylaxis in people with hemophilia A, and real‐world data show similar efficacy and safety from the pivotal studies. Other nonreplacement agents and gene therapy have ongoing studies with promising results. Innovative approaches, like subcutaneous factor VIII and lipid nanoparticles, are in the preclinical phase. These novel agents, such as extended half‐life concentrates and emicizumab, have been available in resource‐constrained countries through the constant efforts of the World Federation of Haemophilia Humanitarian Aid Program. Despite the wide range of new approaches and therapies, the main challenge remains the same: to guarantee treatment for all. In this article, we discuss the evolution of hemophilia care, global access to hemophilia treatment, and the current and future strategies that are now under development. Finally, we summarize relevant new data on this topic presented at the ISTH 2021 virtual congress.

First study of extended half-life rFVIIIFc in previously untreated patients with hemophilia A: PUPs A-LONG final results

PUPs A-LONG is the first study of an extended half-life recombinant factor VIII (rFVIIIFc) in PUPs with hemophilia A.

Incidence of inhibitors for patients with ≥10 exposure days was 31.1%; incidence of high-titer inhibitors was relatively low at 15.6%.

PUPs A-LONG evaluated the safety and efficacy of recombinant factor VIII Fc fusion protein (rFVIIIFc) in previously untreated patients (PUPs) with hemophilia A. This open-label, phase 3 study enrolled male PUPs (<6 years) with severe hemophilia A to receive rFVIIIFc. The primary endpoint was the occurrence of inhibitor development. Secondary endpoints included annualized bleed rate (ABR). Of 103 subjects receiving ≥1 dose of rFVIIIFc, 80 (78%) were aged <1 year at the study start, 20 (19%) had a family history of inhibitors, and 82 (80%) had high-risk F8 mutations. Twenty subjects began on prophylaxis, while 81 began an on-demand regimen (69 later switched to prophylaxis). Eighty-seven (81%) subjects completed the study. Inhibitor incidence was 31.1% (95% confidence interval [CI], 21.8% to 41.7%) in subjects with ≥10 exposure days (or inhibitor); high-titer inhibitor incidence was 15.6% (95% CI, 8.8% to 24.7%). The median (range) time to high-titer inhibitor development was 9 (4-14) exposure days. Twenty-eight (27%) subjects experienced 32 rFVIIIFc treatment-related adverse events; most were inhibitor development. There was 1 nontreatment-related death due to intracranial hemorrhage (onset before the first rFVIIIFc dose). The overall median (interquartile range [IQR]) ABR was 1.49 (0.00-4.40) for subjects on variable prophylaxis dosing regimens. In this study of rFVIIIFc in pediatric PUPs with severe hemophilia A, overall inhibitor development was within the expected range, although high-titer inhibitor development was on the low end of the range reported in the literature. rFVIIIFc was well-tolerated and effective for prophylaxis and treatment of bleeds. This trial is registered at www.clinicaltrials.gov (NCT02234323).

Twice Weekly Vs. Thrice Weekly Low-Dose Prophylactic Factor VIII Therapy in Children with Hemophilia A: An Open Label Randomized Trial

INTRODUCTION

Low dose factor VIII prophylactic therapy in hemophilia has not been well established till date. This randomized controlled trial compared the efficacy of twice vs. thrice weekly schedule of low dose prophylactic factor VIII in children with hemophilia A as evaluated by the bleeding rate and clinico-radiological evaluation.

METHODS

Thirty-three children with severe hemophilia A (≤18 years) were randomized into two groups. Baseline evaluation included detailed history, clinical (HJHS 2.1 score and FISH score) and radiological examination (Pettersson score and ultrasound score). Group 1 received twice weekly factor VIII prophylaxis while group 2 received thrice weekly factor VIII prophylaxis, the dose being 10 U/kg in both groups. All participants were followed up over next 6 months to one year. Data regarding acute bleeding episodes and repeat clinico-radiological assessment at the end of follow up were recorded.

RESULTS

We analyzed 14 children in twice weekly prophylaxis group and 16 children in thrice weekly prophylaxis group. Statistically insignificant difference was found between the bleeding rates in both the groups after prophylaxis with the median values of monthly bleeding rate being 0.17 and p-value of 0.79. The differences between the initial and final clinical and radiological scores within each group were found to be statistically significant. There was no significant difference in the clinical and radiological scores in between the groups.

CONCLUSION

Twice weekly FVIII therapy is effective, easily administered prophylactic schedule to prevent long-term complications of hemophilia A. Lay summaryHemophilia A is one of the most common congenital coagulation factor deficiencies. Low dose factor VIII prophylaxis is recommended for hemophilia in resource-poor settings to reduce the bleeding episodes and improve the quality of life, although the optimal schedule for the same has not been well established. A randomized controlled trial on 33 children with hemophilia A (≤18 years) was done to compare the efficacy of twice versus thrice weekly schedule of prophylactic factor VIII. Group 1 received twice weekly factor VIII prophylaxis while group 2 received thrice weekly factor VIII prophylaxis, the dose in both groups being 10 U/kg. They were evaluated by the bleeding rate and clinical (HJHS 2.1 score and FISH score) and radiological scores (Pettersson score and ultrasound score). All participants were followed up over next 6 months to one year. Data regarding acute bleeding episodes and repeat clinico-radiological assessment at end of follow up were recorded. When analyzed, statistically insignificant difference was found between the bleeding rates after the two prophylaxis regimes. There was a significant improvement between initial and final clinical and radiological scores in both the groups and no difference was recorded in between the groups. To conclude, twice weekly FVIII therapy is effective, easily administered prophylactic schedule to prevent long-term complications of hemophilia A.

The experiences of people with haemophilia and their families of gene therapy in a clinical trial setting: regaining control, the Exigency study

BACKGROUND

Gene therapy has the potential to change the life experience of people with haemophilia and family members. Few studies have sought to explore the impact of gene therapy on both individuals and families. The aim of this study was to capture real-life experiences of gene therapy in People with haemophilia and their families.

RESULTS

Sixteen participants with severe haemophilia (11 haemophilia A, five haemophilia B), mean age 41.4 years (range 23-75 years), took part in a single qualitative interview; ten were accompanied by a family member. Mean time since transfection was 3.56 years (range 1-10 years). Participants saw their involvement in gene therapy as a positive experience, freeing them from the personal burden of haemophilia and furthering treatment options for the wider haemophilia community. However, participants reported being unprepared for the side effects of immunosuppression. Some also reported feeling unsupported and having little control over what was happening as their factor levels became the focus of the process.

CONCLUSION

The results suggest that strategies need to be put into place to enable PwH fully to understand the process of gene therapy, and thereby make an informed choice as to whether it is a treatment they might wish for themselves. These include early and ongoing education, increased provision of psychosocial support and ongoing qualitative research.

Is the world ready for gene therapy?

KEY POINTS OF CONSIDERATION

To prepare for the introduction of gene therapies in haemophilia care, healthcare frameworks for evaluation and valuation will need to evolve to address the unique requirements of current and future innovations for treating this rare disease. The papers in this supplement provide an insightful and comprehensive state-of-the-art assessment of these requirements and challenges. In terms of evaluation, the definition of a patient-defined value framework that captures multi-dimensional, patient-centered outcomes is an important first step for determining the full benefit of gene therapy for persons with haemophilia. In terms of valuation and rewards for innovation, health systems will need to develop alternative payment models for risk-sharing that will allow payers and society to address uncertainties about the ultimate clinical and economic value of these innovations. And health technology assessment authorities will need to exercise greater flexibility in evidence requirements given the unique features of data collection for a potentially curative therapy for a rare disease with long-term uncertainties about durability of impact. Collaboration among stakeholders will be essential for developing the critical evidence requirements and providing the incentives needed to achieve sustainable budgets and broad access for persons with haemophilia worldwide.

The value of ultrasonography in detecting early arthropathic changes and contribution to the clinical approach in patients of hemophilia

PURPOSE\AIM: Hemophilia affects the blood clotting process, is a genetic disease characterized by recurrent bleeding. The hemophilia early arthropathy detection with ultrasound (HEAD-US) procedure and scoring method were designed for the detection of early changes in affected joints of patients. In this article, it was aimed to detect early arthropathic changes in the joints of hemophilia patients with the HEAD US scoring system and to investigate its clinical contribution. It was aimed to investigate the effectiveness of HEAD-US scoring in showing early joint damage in subclinical hemophilia cases and its contribution to treatment.

METHODS

The present study included 50 hemophilia patients who were admitted to Departments of Pediatric and Adult Hematology for routine follow-up. During routine follow-up controls, patients were scored by physical examination and HJHS 2.1 and by ultrasonography and HEAD US. Statistical tests were used to analyze joint health status and the results of US examination in the patient group.

RESULTS

A total of 294 joints (elbow n = 100, knee n = 94, ankle n = 100) were evaluated by ultrasonography. The mean HJHS and HEAD-US scores of the patients were 14.94 ± 15.18 and 15.6 ± 12.6, respectively.

CONCLUSIONS

HEAD-US is accepted to be more sensitive than HJHS in detecting early signs of arthropathy. Detection of early abnormalities by ultrasonography will enable the development of individualized treatment protocols and to the prevention of arthropathy development.

Improvement in pain-related quality of life in patients with hemophilia A treated with rFVIIIFc individualized prophylaxis: post hoc analysis from the A-LONG study

Background:

Pain, a common symptom of hemophilia, begins early in life primarily due to joint bleeding. Recurrent bleeding adversely affects patients’ pain-related physical functioning, which can negatively impact their quality of life (QoL).

Objective:

Post hoc analysis of data from the A-LONG study (NCT01181128), to assess change over time in pain-related QoL in patients with severe hemophilia A treated prophylactically with recombinant factor VIII Fc fusion protein (rFVIIIFc).

Methods:

Patients who completed Haem-A-QoL (17–65 years) and EQ-5D-3L (⩾12–65 years) questionnaires at baseline (BL) and end of study (EoS). Individual-level changes were assessed using three pain-related items of the Haem-A-QoL ‘Physical Health’ domain and the pain/discomfort item of EQ-5D-3L. Distributions of responses (EoS versus BL) were compared using McNemar’s test.

Results:

A significantly greater proportion of patients reported they did not experience painful swellings ( n = 87; 66% versus 46%, p <  0.01) or pain in their joints ( n = 89; 42% versus 27%; p <  0.05) at EoS versus BL. The proportion of patients who did not find it painful to move numerically increased at EoS versus BL ( n = 86; 47% versus 38%; p = NS). A significantly greater proportion of patients reported no pain/discomfort at EoS versus BL ( n = 116; 45% versus 34%; p <  0.05).

Conclusion:

This study reports the effect of FVIII prophylaxis on patient-reported measures of pain over time in patients with severe hemophilia A. The results of this post hoc analysis showed improvements in pain from BL to EoS in patients receiving rFVIIIFc individualized prophylaxis indicating effective pain management, a key component of patient care.

Assessment of global coagulation function under treatment with emicizumab concomitantly with bypassing agents in haemophilia A with inhibitor (UNEBI Study): multicentre open-label non-randomised clinical trial

INTRODUCTION

Subcutaneous emicizumab prophylaxis substantially reduces bleeding episodes in patients with haemophilia A (PwHA) and factor VIII inhibitor. However, thrombotic events occurred in some PwHA with inhibitor who had received high cumulative doses of activated prothrombin complex concentrates at their breakthrough bleeds, when they were also given prophylactic emicizumab. After that, although the recommended guidance was proposed for bypassing agents (BPAs) therapy under emicizumab prophylaxis for haemostatic management, detailed investigation(s) is(are) required to elucidate the safe and appropriate dose of BPAs to use concomitantly with emicizumab prophylaxis.

METHODS AND ANALYSIS

In the UNEBI Study, 60 PwHA with inhibitor will be enrolled for a maximum duration of 3 years, and samples of 20 events following concomitant use of BPAs with emicizumab will be collected. An 'event' is defined as obtaining blood samples before and after administration of BPA when a breakthrough bleed or a surgical procedure occurs. The coagulation potential in the obtained samples will be measured by global coagulation assays. The primary endpoint is the degree of improvement in the maximum coagulation rate by clot waveform analysis (CWA) before and after administration of fixed-dose BPAs. This parameter obtained from CWA, which is triggered with an optimally diluted mixture of prothrombin time/activated partial thromboplastin time-reagents, is reported to be an excellent marker for assessing the degree of improvement in coagulation potential in emicizumab-treated plasma.

ETHICS AND DISSEMINATION

The UNEBI Study was approved by the Japan Certified Review Board of Nara Medical University. The results of the study will be communicated through publication in international scientific journals and presentations at (inter)national conferences.

TRIAL REGISTRATION NUMBER

jRCTs051190119.

Managing Severe Hemophilia A in Children: Pharmacotherapeutic Options

Hemophilia A is the most common severe inherited bleeding disorder in males. Initial treatment strategies focused on the use of factor concentrates to prevent joint bleeding and the development of long-term crippling arthropathy. The current standard of care has evolved from regular replacement of factor VIII concentrates which has significantly improved the quality of life for those with severe disease to include and consider novel therapies that augment or bypass the hemostatic pathway (ie, emicizumab, Mim8). Other pipeline therapies that suppress specific natural anticoagulant pathways (ie, antithrombin, TFPI) to reestablish hemostatic balance are under Phase 3 trial investigation. These novel therapeutics have allowed providers more variety in dosing regimens and ease of administration while also maintaining effective bleeding prevention. The possibility of "curative" gene therapy is under exploration, with ongoing clinical trials in adult males.

Current Choices and Management of Treatment in Persons with Severe Hemophilia A without Inhibitors: A Mini-Delphi Consensus

BACKGROUND

Regular treatment to prevent bleeding and consequent joint deterioration (prophylaxis) is the standard of care for persons with severe hemophilia A, traditionally based on intravenous infusions of the deficient clotting FVIII concentrates (CFCs). In recent years, extended half-life (EHL) CFCs and the non-replacement agent emicizumab, subcutaneously administered, have reduced the treatment burden.

METHODS

To compare and integrate the opinions on the different therapies available, eight hemophilia specialists were involved in drafting items of interest and relative statements through the Estimate-Talk-Estimate (ETE) method ("mini-Delphi"), in this way reaching consensus.

RESULTS

Eighteen items were identified, then harmonized to 10, and a statement was generated for each. These statements highlight the importance of personalized prophylaxis regimens. CFCs, particularly EHL products, seem more suitable for this, despite the challenging intravenous (i.v.) administration. Limited real-world experience, particularly in some clinical settings, and the lack of evidence on long-term safety and efficacy of non-replacement agents, require careful individual risk/benefit assessment and multidisciplinary data collection.

CONCLUSIONS

The increased treatment options extend the opportunities of personalized prophylaxis, the mainstay of modern management of hemophilia. Close, long-term clinical and laboratory follow-up of patients using newer therapeutic approaches by specialized hemophilia treatment centers is needed.

Costs and management of patients with hemophilia A in France: the Hemraude study

OBJECTIVE

The Hemraude study was conducted to describe the profile of patients with HA, disease management, and economic burden in a collective perspective.

METHODS

This retrospective study was conducted using the French administrative healthcare claims database SNIIRAM/SNDS. Male patients treated for hemophilia A with a long-term illness (ALD) status or invalidity were included in the study between January 1, 2016 and December 31, 2017. Patients were classified in six treatment groups: no treatment, on-demand FVIII, prophylactic FVIII, FVIII in immune tolerance induction (ITI) protocol, on-demand bypassing agents, and prophylactic bypassing agents. Patients treated with FVIII in ITI protocol and those treated with bypassing agents are deemed to have developed inhibitors. HA patients were compared to a control population without coagulation disorder and matched (ratio 1:3) on age and sex.

RESULTS

A total of 4172 patients were included in the analysis, aged on average 35.2 years, 5.3% had HIV infection, and 8.8% had hepatitis B or C. In 2017, half of the patients received no treatment for HA, 46.7% were treated with FVIII (25% on demand, 20.6% with prophylaxis, and 1.1% ITI), 1.5% with bypassing agents. Patients treated with prophylactic treatments, either inhibitor or non-inhibitor, were less likely to be hospitalized for severe bleeding compared to patients receiving on-demand treatments. The average annual costs for HA management per patient were 72,209.60 €. The highest costs were observed in patients treated with FVIII in ITI protocol and those receiving prophylactic bypassing agents.

CONCLUSION

Direct costs of HA treatments for HA may be very high especially in the small percentage of patients developing inhibitors or treated with ITI protocol.

Effects of replacement therapies with clotting factors in patients with hemophilia: A systematic review and meta-analysis

Background

Different prophylactic and episodic clotting factor treatments are used in the management of hemophilia. A summarize of the evidence is needed inform decision-making.

Objective

To compare the effects of factor replacement therapies in patients with hemophilia.

Methods

We performed a systematic search in PubMed, Central Cochrane Library, and Scopus. We included randomized controlled trials (RCTs) published up to December 2020, which compared different factor replacement therapies in patients with hemophilia. Random-effects meta-analyses were performed whenever possible. The certainty of the evidence was assessed using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) methodology. The study protocol was registered in PROSPERO (CRD42021225857).

Results

Nine RCTs were included in this review, of which six compared episodic with prophylactic treatment, all of them performed in patients with hemophilia A. Pooled results showed that, compared to the episodic treatment group, the annualized bleeding rate was lower in the low-dose prophylactic group (ratio of means [RM]: 0.27, 95% CI: 0.17 to 0.43), intermediate-dose prophylactic group (RM: 0.15, 95% CI: 0.07 to 0.36), and high-dose prophylactic group (RM: 0.07, 95% CI: 0.04 to 0.13). With significant difference between these subgroups (p = 0.003, I² = 82.9%). In addition, compared to the episodic treatment group, the annualized joint bleeding rate was lower in the low-dose prophylactic group (RM: 0.17, 95% CI: 0.06 to 0.43), intermediate-dose prophylactic group (RM of 0.14, 95% CI: 0.07 to 0.27), and high-dose prophylactic group (RM of 0.08, 95% CI: 0.04 to 0.16). Without significant subgroup differences. The certainty of the evidence was very low for all outcomes according to GRADE methodology. The other studies compared different types of clotting factor concentrates (CFCs), assessed pharmacokinetic prophylaxis, or compared different frequencies of medication administration.

Conclusions

Our results suggest that prophylactic treatment (at either low, intermediate, or high doses) is superior to episodic treatment for bleeding prevention. In patients with hemophilia A, the bleeding rate seems to have a dose-response effect. However, no study compared different doses of prophylactic treatment, and all results had a very low certainty of the evidence. Thus, future studies are needed to confirm these results and inform decision making.

Gastrointestinal Bleeding in Congenital Bleeding Disorders

Gastrointestinal bleeding (GIB) is serious, intractable, and potentially life-threatening condition. There is considerable heterogeneity in GIB phenotypes among congenital bleeding disorders (CBDs), making GIB difficult to manage. Although GIB is rarely encountered in CBDs, its severity in some patients makes the need for a comprehensive and precise assessment of underlying factors and management approaches imperative. Initial evaluation of GIB begins with assessment of hematological status; GIB should be ruled out in patients with chronic anemia, and in presentations that include hematemesis, hematochezia, or melena. High-risk patients with recurrent GIB require urgent interventions such as replacement therapy for treatment of coagulation factor deficiency (CFD). However, the best management strategy for CFD-related bleeding remains controversial. While several investigations have identified CBDs as potential risk factors for GIB, research has focused on assessing the risks for individual factor deficiencies and other CBDs. This review highlights recent findings on the prevalence, management strategies, and alternative therapies of GIB related to CFDs, and platelet disorders.

Twelve-month prevalence of haemarthrosis and joint disease using the Haemophilia Joint Health score: evaluation of the UK National Haemophilia Database and Haemtrack patient reported data: an observational study

OBJECTIVES

To report the 12-month prevalence of joint bleeds from the National Haemophilia Database (NHD) and Haemtrack, a patient-reported online treatment diary and concurrent joint disease status using the haemophilia joint health score (HJHS) at individual joint level, in children and adults with severe haemophilia A and B (HA/HB) without a current inhibitor.

DESIGN

A 2018 retrospective database study of NHD from which 2238 cases were identified, 463 patients had fully itemised HJHS of whom 273 were compliant in recording treatment using Haemtrack.

SETTING

England, Wales and Scotland, UK.

PARTICIPANTS

Children (<18 years) and adults (≥18 years) with severe HA and HB (factor VIII/factor IX, <0.01 iu/mL) without a current inhibitor.

PRIMARY AND SECONDARY OUTCOMES

Prevalence of joint haemarthrosis and concurrent joint health measured using the HJHS.

RESULTS

The median (IQR) age of children was 10 (6-13) and adults 40 (29-50) years. Haemarthrosis prevalence in HA/HB children was 33% and 47%, respectively, and 60% and 42%, respectively, in adults. The most common site of haemarthrosis in children was the knee in HA and ankle in HB. In adults, the incidence of haemarthrosis at the ankles and elbows was equal. The median total HJHS in HA/HB children was 0 and in adults with HA/HB, were 18 and 11, respectively. In adults with HA/HB, the median ankle HJHS of 4.0 was higher than the median HJHS of 1.0 for both the knee and elbow.

CONCLUSION

Despite therapeutic advances, only two-thirds of children and one-third of adults were bleed-free, even in a UK cohort selected for high compliance with prophylaxis. The median HJHS of zero in children suggests joint health is relatively unaffected during childhood. In adults, bleed rates were highest in ankles and elbows, but the ankles led to substantially worse joint health scores.

Bone mineral density in haemophilia - a multicentre study evaluating the impact of different replacement regimens

AIM

The aim of this study was to investigate if prophylactic treatment in severe haemophilia impact on bone mineral densisty (BMD) in adults with haemophilia A/B.

METHODS

Subjects with haemophilia (n = 120) underwent bone-density measurement and clinical data was collected. BMD in subjects with severe haemophilia on high-dose prophylaxis (n = 41) was compared to BMD in subjects with mild haemophilia (n = 33) and to severe haemophilia treated with intermediate-dose prophylaxis (n = 32) or on-demand replacement therapy (n = 14).

RESULTS

Subjects with severe haemophilia on high-dose prophylaxis showed BMD at total hip comparable to subjects with mild haemophilia (median BMD 955.8 and 977.4 mg/cm² (P = .17), respectively). No difference in BMD was found related to type of prophylactic regimen (median BMD 955.8 and 942.4 mg/cm² , in high-dose and intermediate dose groups, respectively; P = .70). Subjects with severe disease treated on-demand had significantly lower BMD compared to subjects on a high-dose prophylactic regimen (median BMD 771.8 and 955.8 mg/cm² (P = .001), respectively). BMD decreased significantly with age, regardless of severity of haemophilia disease. In a multivariate analysis, adjusted for disease status and age, type of prophylactic regimen was not significantly associated with osteoporosis development.

CONCLUSION

We show that BMD differs in persons with severe haemophilia on propylaxis as compared to those treated on-demand, but that type of prophylactic regimen does not reflect on BMD. The difference between treatment groups was mainly explained by an age difference between groups. However, patients on prophylaxis displayed a high degree of normal BMD not far from mild haemophilia at comparative age.

Analysis of nationwide hemophilia care: A cohort study using two Japanese healthcare claims databases

BACKGROUND AND AIMS

In many developed countries, hemophilia care is provided by specialized centers which can offer standardized high-quality care for patients and collect data for patient registries. However, in countries with less centralized provision of hemophilia care, registry data lacks accuracy and medical care is inconsistent among providers. Claims databases can be an alternative for obtaining nationwide data on hemophilia care, and we applied this approach to evaluate inequalities in hemophilia care in Japan.

METHODS

Medical records of hemophilia A patients were collected by a combination of ICD-10 code (D66) and prescribed coagulation factors from two major Japanese claims databases (JMDC and Medical Data Vision [MDV]). Patient records with an anti-inhibitor coagulant complex were excluded.Based on the annual number of hemophilia A patients, medical facilities were categorized into specialized facilities (SP, ≥5 patients) and nonspecialized facilities (N-SP, <5 patients). Patient age, comorbidities, diagnostic testing, prescribed drugs and their dosages were compared between facility types.

RESULTS

The JMDC and MDV databases included 274 and 1266 hemophilia A patients, respectively. In the MDV database, SP facilities prescribed extended half-life factor VIII (FVIII) products for more patients (31.8% vs 24.3%) than N-SP. The mean annual FVIII consumption per patient was higher in SP facilities (240 333 IU [international units] vs 210 334 IU), and the mean FVIII dosage was higher in SP facilities for all types of FVIII products. The proportion of patients who received diagnostic blood tests was higher in SP (75.7% vs 56.2%).

CONCLUSION

The MDV database revealed disparities in hemophilia A care between SP and N-SP facilities in types of FVIII products prescribed, FVIII consumption, and frequency of the relevant management such as blood tests. Claims databases can be an alternative for the assessment of nationwide hemophilia care patterns in countries without a well-established registry.

Combining factor VIII levels and thrombin/plasmin generation: a population pharmacokinetic-pharmacodynamic model for patients with hemophilia A

Aims

Prophylactic treatment of haemophilia A patients with factor VIII (FVIII) concentrate focuses on maintaining a minimal trough FVIII activity level to prevent bleeding. However, due to differences in bleeding tendency, the pharmacokinetic (PK)‐guided dosing approach may be suboptimal. An alternative approach could be the addition of haemostatic pharmacodynamic (PD) parameters, reflecting a patient's unique haemostatic balance. Our aim was to develop a population PK/PD model, based on FVIII activity levels and Nijmegen Haemostasis Assay (NHA) patterns, a global haemostatic assay that measures thrombin/plasmin generation simultaneously.

Methods

PK/PD measurements were collected from 30 patients treated with standard half‐life FVIII concentrate. The relationship between FVIII activity levels and the thrombin/plasmin generation parameters (thrombin potential, thrombin peak height and plasmin peak height), were described by sigmoidal E_max functions.

Results

The obtained EC₅₀ value was smallest for the normalized thrombin potential (11.6 IU/dL), followed by normalized thrombin peak height (56.6 IU/dL) and normalized plasmin peak height (593 IU/dL), demonstrating that normalized thrombin potential showed 50% of the maximal effect at lower FVIII activity levels. Substantial inter‐individual variability in the PD parameters, such as EC₅₀ of thrombin potential (86.9%) was observed, indicating that, despite similar FVIII activity levels, haemostatic capacity varies significantly between patients.

Conclusion

These data suggest that dosing based on patients' individual PK/PD parameters may be beneficial over dosing solely on individual PK parameters. This model could be used as proof‐of‐principle to examine the application of PK/PD‐guided dosing. However, the relation between the PD parameters and bleeding has to be better defined.

How do we optimally utilize factor concentrates in persons with hemophilia?

The current mainstay of therapy for hemophilia is to replace the deficient clotting factor with the intravenous administration of exogenous clotting factor concentrates. Prophylaxis factor replacement therapy is now considered the standard of care in both pediatric and adult patients with hemophilia with a severe phenotype to protect musculoskeletal health and improve quality of life. Heterogeneity in bleeding presentation among patients with hemophilia due to genetic, environmental, and treatment-related factors has been well described. Accordingly, the World Federation of Hemophilia recommends an individualized prophylaxis regimen that considers the factors mentioned above to meet the clinical needs of the patient, which can vary over time. This review focuses on the practical points of choosing the type of factor concentrate, dose, and interval while evaluating appropriate target trough factor levels and bleeding triggers such as level of physical activity and joint status. We also discuss the use of a pharmacokinetics assessment and its incorporation in the clinic for a tailored approach toward individualized management. Overall, adopting an individualized prophylaxis regimen leads to an optimal utilization of factor concentrates with maximum efficacy and minimum waste.

The lived experience of a novel disruptive therapy in a group of men and boys with haemophilia A with inhibitors: Emi & Me

BACKGROUND

People with haemophilia A and inhibitors (PwHi) suffer more orthopaedic complications, bleeding and pain than those without inhibitors. The advent of emicizumab as a prophylactic treatment has led to a reduction in bleed frequency and a significant improvement in overall quality of life. No research to date has examined the nature of this improvement on treated individuals and their families.

AIMS

The Emi & Me study aims to capture the real-life experience of using emicizumab for PwHi and their families.

METHODS

Participants were recruited through treatment centres, social media and by word of mouth. Each participant and a family member, if available, took part in a semistructured qualitative interview. All interviews were recorded, transcribed verbatim and analysed thematically. All elements of the study were reviewed by local statutory authorities and informed consent was sought from all participants.

RESULTS

Fifteen PwHi, mean age 27.2 years (range 8-63 years), most with a family member, participated in a single qualitative interview online (n = 13), by telephone (n = 1) or in person (n = 1). Mean time on emicizumab was 2.26 years (range 1-5 years). Six major themes emerged: bleeds; pain; treatment burden; control; freedom (for both PwHi and family members) and missed potential. Emicizumab prophylaxis has delivered significant improvements in the lives of the participants. Despite these improvements, some participants felt that their pre-existing physical disabilities and the lack of physiotherapy provision had prevented them achieving similar improvements in their functional ability.

CONCLUSION

This study shows that in reducing bleeds, pain and treatment burden, emicizumab had given PwHi greater control over their condition, allowing a sense of freedom they had not experienced with factor VIII or bypassing agent prophylaxis. However, for emicizumab to be truly effective, there is a need to ensure the continued availability and accessibility of robust multidisciplinary support services. Without this, it is unlikely that PwHi will realize the life-changing potential offered either by emicizumab or any other novel treatment approach.

PATIENT OR PUBLIC CONTRIBUTION

A patient participant (who did not wish to be included as an author of the paper) was involved in the design of the study protocol and interview guide.

Clinical Utility of Subcutaneous Factor VIII Replacement Therapies in Hemophilia A: A Review of the Evidence

Hemophilia therapies have tremendously improved over the last decades with the development of prolonged half-life factor VIII (FVIII) and FIX concentrates, non-factor therapies, such as emicizumab, anti-TFPI antibodies or siRNA antithrombin and gene therapy. All of these new molecules significantly reduced the burden of the disease and improved the quality of life of patients with severe hemophilia. Emicizumab, a non-factor therapy, is currently the only subcutaneous molecule available for prophylactic treatment of severe hemophilia A. Because of the subcutaneous route of delivery and similar efficacy to FVIII replacement therapy, emicizumab has been rapidly adopted by patients and their families. This clinical observation emphasizes the relevance and need for the development of subcutaneous FVIII concentrates. Here, we report evidence-based advantages and interest in the subcutaneous route of administration for the treatment of hemophilia A and review the stages of development of the different subcutaneous FVIII molecules.