A study of variations in the reported haemophilia A prevalence around the world

Quantification of the contribution of individual coagulation factors to haemostasis using a microchip flow chamber system and reconstituted blood from deficient plasma

BACKGROUND AND OBJECTIVES

Quantifying the contribution of individual coagulation factors to haemostasis may aid our understanding of the haemostatic function in patients with rare coagulation deficiencies (RCDs) and the exploration of suitable treatments.

MATERIALS AND METHODS

Reconstituted blood prepared from specific coagulation factor-deficient plasma (factor [F]II; prothrombin, FV, FVII, FVIII, FIX, FX, FXI or FXII) and red blood cell/platelet products were used to simulate the whole blood of patients with RCD. We prepared in vitro treatment models for patients with prothrombin deficiency using coagulation factor agents and fresh frozen plasma. Haemostatic function was measured using a microchip flow chamber system at 600 s-1.

RESULTS

The haemostatic function was low, especially in blood samples reconstituted with prothrombin- and FX-deficient plasma. In a plasma transfusion model of prothrombin deficiency, haemostatic function recovered after 10% replacement with normal plasma and reached a plateau at ≧60% replacement. A treatment model of prothrombin deficiency with prothrombin complex concentrates revealed dose-dependent therapeutic effects in the range of 0-50 IU/kg.

CONCLUSION

Microchip flow chamber system-based quantification of haemostatic function using reconstituted blood could predict haemostasis and therapeutic effects of treatments in patients with prothrombin deficiency.

The prevalence of Hemophilia A in males in Africa: evidence from a systematic review and meta-analysis

BACKGROUND

Hemophilia A (HA) is an X-linked recessive bleeding disorder characterized by reduced or absent coagulation factor (F) VIII activity. The empirical evidence on the prevalence of HA in Africa has reported inconsistent findings and seems to present such a wide range of prevalence that it is hard to swiftly ascertain its average extent. Hence, this review aimed to pool the results of primary studies reporting the prevalence of HA into a single estimate in the region.

METHODS

We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Articles published in EMBASE, PubMed, Web of Science, SCOPUS, Science Direct, and Cochrane Library databases were searched. Observational studies revealing the prevalence of HA in Africa between 2010 and 2023 were incorporated. We assessed the quality of each study using the Newcastle-Ottawa quality assessment tool. The prevalence of HA was estimated as the cases (the sample size) per 100,000 population multiplied by 1000. To produce the pooled estimate, Der Simonian random-effects models were computed with Metaprop on the STATA command. The studies' heterogeneity was assessed using the I-squared (I2) value test and the Galbraith plot. A funnel plot was conducted to evaluate publication bias.

RESULTS

Of the 337 studies accessed, we included 15 that fulfilled the eligibility criteria. The random-effect model meta-analysis demonstrated the overall pooled prevalence of HA was 6.82 cases per 100,000 persons (95% confidence interval: 5.16, 8.48) with heterogeneity (I2 = 0.00%, p < 0.001).

CONCLUSIONS

This systematic review and meta-analysis revealed that HA is an alarming problem that may pose a future threat to public health in Africa. Given the detrimental effects of the disease on health and the complications involved, we recommended that African regions increase patient access to factor VIII medication, improve carrier detection rates, and take the initiative toward the development and access to gene therapy.

Prevalence of Hemophilia and Clinicodemographic Characteristics of Hemophilic Patients Aged ≤ 18 Years in Thi-Qar, Iraq

Objectives. This study aims to determine the prevalence of hemophilia in Thi-Qar, Iraq and study clinical and demographic characteristics of patients with hemophilia. Methods. In this cross-sectional study, data were obtained by reviewing all patient medical records and interviewed with the patients and their parents in 2022. The total number of patients enrolled for this study was 110 children. Results. The prevalence of hemophilia in Thi-Qar was 9.5/100 000 population (18.7/100 000 males). Factor VIII inhibitors were positive in 13.1% of patients with hemophilia A (HA). Target joints were developed among 41.4% and 27.3% of patients with HA and hemophilia B, respectively. Hepatitis C virus was positive in 3% of those with HA. Inhibitors development and arthropathy were more among those with severe disease (22% and 46.3%, respectively). Conclusion. Hemophilia prevalence in Thi-Qar was higher than the total prevalence in Iraq reported by World Federation of Hemophilia in 2022.

Shared decision-making related to treatment of haemophilia: A scoping review of influential factors and available support tools

INTRODUCTION

Treatment selection in haemophilia is increasingly challenging given evolving therapeutic options and the need for individualization. Shared decision-making (SDM) approaches have recently gained interest, though a synthesis of available studies is lacking.

AIM

A scoping review was conducted to summarize literature reporting on factors impacting treatment SDM in haemophilia and tools or models available to support such decisions.

METHODS

PubMed, Embase, the Cochrane Library, Web of Science and grey literature were searched for studies published through August 2023. Original studies reporting on facilitators and barriers to haemophilia SDM and SDM tools were included and analyzed for themes, characteristics and gaps.

RESULTS

A total of 625 records were identified and 14 unique studies were selected (factors influencing treatment SDM, n = 7; SDM tools, n = 7). The studies typically included input from persons with haemophilia, caregivers and healthcare practitioners (HCPs). Thematic organization of factors influencing SDM revealed three main categories: knowledge, patient characteristics and HCP-patient interactions. Availability of information was a commonly reported facilitator of SDM, while poor HCP-patient engagement was a commonly reported barrier. Tools varied in focus, with some facilitating general treatment SDM while others supported selection of certain therapy types. The studies underscored additional factors critical for SDM, such as alignment of HCP-patient perceptions, shared language and tailoring of tools to specific subpopulations.

CONCLUSION

Few studies report on treatment SDM factors and tools in haemophilia; available tools vary considerably. It remains unclear whether published tools have been successfully implemented into clinical practice. Additional research is warranted.

Management of Urgent Bleeding in Patients with Hemophilia A: Focus on the Use of Emicizumab

Management of patients with hemophilia A (HA) requires the knowledge and experience of specialized health care professionals. However, these patients may need to be attended in emergencies, outside the referral hospital, where health care professionals do not know about hemophilia and/or new innovative treatments. This study aimed to develop a simple and practical algorithm that could be used in emergency situations by nonspecialized treaters in HA and bleeding with or without factor VIII (FVIII) inhibitors under emicizumab prophylaxis. A group of experts agreed on a simple algorithm, easy to operate, adapted from previous international guidelines, and based on their clinical experience. The proposed algorithm starts with identifying the patient, confirming the diagnosis of HA, prophylaxis with emicizumab, and/or use of other treatments. After stabilizing the patient and stratifying the bleeding risk, the patient is managed according to the presence/absence of FVIII inhibitors. Patients without FVIII inhibitors should receive FVIII concentrate. Dose and follow-up depend on bleeding localization and severity. Patients with FVIII inhibitors should preferably receive recombinant activated factor VII as bypass agent. A basic coagulation assay, FVIII assessment, and FVIII inhibitors detection assays are necessary in an emergency. However, these tests should be interpreted with caution and appropriately chosen, as emicizumab may alter the results. The management of patients with HA is challenging in emergency situations, especially if they are treated with new agents. Nonspecialized in coagulopathies health care professionals have limited understanding of the disease, highlighting the need for an algorithm to assist them in making informed decisions.

Effects of Plyometric-Based Hydro-Kinesiotherapy on Pain, Muscle Strength, Postural Stability, and Functional Performance in Children with Hemophilic Knee Arthropathy: A Randomized Trial

AIM

To explore how plyometric-based hydro-kinesiotherapy (Plyo-HKT) would affect pain, muscle strength, postural stability, and functional performance in a convenience sample of children with hemophilic knee arthropathy (HKA).

METHODS

Forty-eight children with HKA (age: 8-16 years) were randomly allocated to the Plyo-HKT group (n = 24; underwent the Plyo-HKT for 45 min, twice/week over 12 wk in succession) or the comparison group (n = 24; performed the standard exercise rehabilitation at an equivalent frequency and duration). Pain, peak concentric torque of quadriceps and hamstring (produced at two angular velocities: 120 and 180 o/sec), dynamic limits of postural stability (DLPS), and functional performance [Functional Independence Score in Hemophilia (FISH) and 6-Minute Walk Test (6-MWT)] were assessed pre- and post-intervention.

RESULTS

In contrast with the comparison group, the Plyo-HKT group achieved more favorable pre-to-post changes in pain (p = .028, η2p = 0.10), peak torque of quadriceps [120°/sec (p = .007, η2P = 0.15); 180°/sec (p = .011, η2P = 0.13)] and hamstring [120°/sec (p = .024, η2P = 0.11); 180°/sec (p = .036, η2P = 0.09)], DLPSdirectional [forward (p = .007, η2P = 0.15); backward (p = .013, η2P = 0.12); affected side (p = .008, η2P = 0.14); non-affected side (p = .002, η2P = 0.20)], DLPSoverall (p < .001, η2P = 0.32), and functional performance [FISH (p < .001, η2p = 0.26); 6-MWT (p = .002, η2p = 0.19)].

CONCLUSION

Plyo-HKT is likely helpful for reducing pain, improving strength, enhancing postural stability, and boosting functional capabilities in children with HKA. Physical rehabilitation practitioners should, therefore, consider this intervention strategy.

Efficacy and Safety of Adeno-Associated Virus-Based Clinical Gene Therapy for Hemophilia: A Systematic Review and Meta-Analysis

Clinical trials of adeno-associated virus (AAV)-based gene therapy have made remarkable progress in recent years. We aimed to perform a systematic review and meta-analysis of the literature to assess the efficacy and safety of AAV-based gene therapy for hemophilia. We systematically searched the Web of Science, Embase, PubMed, and the Cochrane Database of Systematic Reviews databases, for clinical trials involving patients diagnosed with hemophilia and treated with AAV-mediated gene therapy. Data on the annualized bleeding rate (ABR), annualized infusion rate (AIR), the incidence of treatment-related adverse events (TRAEs), severe adverse events (SAEs), and alanine aminotransferase (ALT) elevation were extracted as our outcomes. A total of 12 articles from 11 clinical trials were selected from 868 articles for meta-analysis. Pooled analyses showed that AAV-based gene therapy in hemophilia patients reduced the number of bleeding events and the number of factor infusion events by an approximate average of 7 per year and 103 per year, respectively. Eighty percent, 18%, and 63% of hemophilia patients had elevated TRAE, SAE, and ALT levels, respectively. Moreover, subgroup analysis found a significant reduction in ABR and AIR 2-3 years after the therapy. Additional findings that were not pooled including coagulation factor activity are presented in the accompanying tables. Our analysis supported the efficacy and safety of AAV-mediated gene therapy for hemophilia, providing evidence for its application as a therapeutic option for widespread clinical use in hemophilia patients in the future.

Arthropathy on X-rays in 363 persons with hemophilia: long-term development, and impact of birth cohort and inhibitor status

Background

Arthropathy following repeated bleeding is common in persons with hemophilia. Since the introduction of prophylaxis, treatment has intensified and joint health has improved. However, data on the long-term development of arthropathy are still scant.

Objectives

To evaluate long-term arthropathy development since the introduction of prophylaxis according to birth cohort, hemophilia severity, and inhibitor status.

Methods

This single-center historic cohort study included persons with severe and moderate hemophilia A and hemophilia B born between 1935 and 2005. Arthropathy on X-rays was evaluated using the Pettersson score. Patient and joint characteristics were studied per birth cohort (<1970, 1970-1980, 1981-1990, and >1990) and compared according to hemophilia severity. The distribution of affected joints and cumulative incidence of arthropathy were analyzed. The association of Pettersson score with birth cohort and inhibitor characteristics was explored using multivariable regression analyses adjusted for age at evaluation.

Results

In total, 1064 X-rays of 363 patients were analyzed. Of persons with severe hemophilia (n = 317, 87.3%), 244 (77.0%) developed arthropathy. Prophylaxis was started at younger ages over time, from a median of 18 to 2.1 years, and concomitantly, arthropathy decreased in consecutive birth cohorts. Ankles were most commonly affected in 188 of 258 (72.9%) patients. Persons with moderate hemophilia (n = 46, 12.7%) had a lower risk of arthropathy (27/46 [58.7%]), but a reduction over time was less pronounced. In the multivariable analyses, birth cohort and age at evaluation were predictors for the development of arthropathy, while inhibitor status showed no association.

Conclusion

The development and severity of arthropathy have decreased over the past decades. However, patients have remained at risk for developing arthropathy, especially in their ankles.

Iron overload causes macrophages to produce a pro-inflammatory phenotype in the synovium of hemophiliac arthritis via the acetyl-p53 pathway

AIM

Haemophiliac arthritis (HA) is caused by spontaneous intra-articular hemorrhage and repeated intra-articular hematomas, leading to iron overload, which, in turn, induces M1 macrophage polarisation and inflammatory cytokine secretion, resulting in synovitis. Here, we explored the mechanism by which iron overload in HA induces the polarisation of M1 macrophages, providing a new approach for the treatment of HA synovitis.

METHODS

The synovium from the knee joints of normal amputees and patients with HA was collected. Pathological changes in the synovial tissues were analysed using hematoxylin and eosin staining. Iron tissue deposition was evaluated using the iron assay kit and Prussia Blue staining, while macrophage phenotype was determined using immunofluorescence. The levels of pro-inflammatory cytokines and p53 acetylation were determine using western blotting. An in vitro iron overload model was established by inducing THP-1 macrophages with ferric ammonium citrate, and the involvement of acetylated p53 in M1 macrophage polarisation was investigated.

RESULTS

Compared to control samples, the iron content in the synovium of patients with HA was significantly increased. The protein levels of M1 macrophage markers, pro-inflammatory cytokines, and acetylated p53, were also significantly elevated in the synovial tissues of patients with HA. Similar results were observed in the in vitro iron overload model. Furthermore, the inhibition of p53 acetylation in vitro reversed these iron overload-induced effects.

CONCLUSION

In patients with HA, iron overload induced synovial p53 acetylation, leading to macrophage polarisation toward the M1 phenotype and increased inflammatory cytokine secretion, resulting in synovitis.

HIGHLIGHTS

Synovial iron overload is associated with changes in P53 acetylation in hemophiliac arthritis (HA). Acetylated p53, a known regulator of macrophage polarization, is highly expressed in HA synovium, suggesting a potential role in M1 polarization. HA synovial macrophages predominantly polarize into the pro-inflammatory M1 phenotype, secreting elevated levels of pro-inflammatory cytokines.

Robust preimplantation genetic testing of the common F8 Inv22 pathogenic variant of severe hemophilia A using a highly polymorphic multi-marker panel encompassing the paracentric inversion

BACKGROUND

Hemophilia A (HEMA) is an X-linked bleeding disorder caused by reduced/absent coagulation factor VIII expression, as a result of pathogenic variants in the F8 gene. Preimplantation prevention of HEMA should ideally include direct pathogenic F8 variant detection, complemented by linkage analysis of flanking markers to identify the high-risk F8 allele. Linkage analysis is particularly indispensable when the pathogenic variant cannot be detected directly or identified. This study evaluated the suitability of a panel of F8 intragenic and extragenic short tandem repeat markers for standalone linkage-based preimplantation genetic testing for monogenic disorder (PGT-M) of the Inv22 pathogenic variant, an almost 600 kb paracentric inversion responsible for almost half of all severe HEMA globally, for which direct detection is challenging.

METHODS

Thirteen markers spanning 1 Mb and encompassing both F8 and the Inv22 inversion interval were genotyped in 153 unrelated females of Viet Kinh ethnicity.

RESULTS

All individuals were heterozygous for ≥ 1 marker, ~ 90% were heterozygous for ≥ 1 of the five F8 intragenic markers, and almost 98% were heterozygous for ≥ 1 upstream (telomeric) and ≥ 1 downstream (centromeric) markers. A prospective PGT-M couple at risk of transmitting F8 Inv22 were fully informative at four marker loci (2 intra-inversion, 1 centromeric, 1 telomeric) and partially informative at another five (2 intra-inversion, 3 centromeric), allowing robust phasing of low- and high-risk haplotypes. In vitro fertilization produced three embryos, all of which clearly inherited the low-risk maternal allele, enabling reliable unaffected diagnoses. A single embryo transfer produced a clinical pregnancy, which was confirmed as unaffected by amniocentesis and long-range PCR, and a healthy baby girl was delivered at term.

CONCLUSION

Robust and reliable PGT-M of HEMA, including the common F8 Inv22 pathogenic variant, can be achieved with sufficient informative intragenic and flanking markers.

Von Willebrand disease: Gaining a global perspective

INTRODUCTION

Recent guidelines for von Willebrand Disease (VWD) highlighted the challenges in diagnosis and management. Identifying the number of persons with VWD (PwVWD) internationally will help target support to aid diagnosis of PwVWD.

AIM

To examine international registration rates of PwVWD, the influence of income status, geographical region and the age and sex profile. Cumulatively, these data will be used to inform future strategy from the World Federation of Haemophilia (WFH) to address unmet clinical and research needs.

METHODS

Data from the 2018/2019 WFH Annual Global Survey (AGS) were analysed, providing a global perspective on VWD registration.

RESULTS

Registration rates are lowest in South Asia (0.6/million population) and highest in Europe/Central Asia (50.9/million population, 0.005%), but below the expected prevalence rate (0.1%). National economic status impacted VWD registration rates, reflecting variation in access to optimal healthcare infrastructure. Females represented the majority of PwVWD globally, however, in low-income countries (LIC) males predominated. Age profile varied, with markedly higher rates of paediatric registrations in North America, Middle East and North Africa and South Asia. Rates of type 3 VWD registrations were significantly influenced by economic status (81% of VWD diagnoses in LIC), suggesting only the most severe VWD types are diagnosed in resource limited settings.

CONCLUSION

Significant variation in registration rates of PwVWD exist internationally and is influenced by income status and the presence of HTC networks. Improved understanding of registration rates will enable targeting of advocacy to improve awareness, diagnosis and support for PwVWD internationally.

KEY POINTS

Registration rates of People with Von Willebrand Disease (PwVWD) vary internationally and are influenced by national income status Although females represent the majority of PwVWD globally, in low income countries (LIC) males predominated, possibly related to stigma surrounding gynaecological bleeding. Rates of type 3 VWD registration were significantly influenced by economic status (81% of VWD diagnoses in LIC), suggesting only the most severe VWD types are diagnosed in resource limited settings.

Development of a telematic pharmaceutical care app (Haemoassist) for multidisciplinary follow-up of patients with congenital coagulopathies

BACKGROUND

Guidelines for congenital coagulopathies recommend that patients record treatment administrations and bleeding episodes to help healthcare professionals monitor the disease.

RESEARCH DESIGN AND METHODS

We studied over two years which patient profiles (age, treatment regimen, treatment compliance) were most likely to accept the use of an app to collect this information. We validated the quality of patient-reported data by comparing it with data obtained from hospital electronic records, pharmacy dispensing records and patient interview, collected in an access database used as a reference. Patient and professional opinions were solicited through open-ended interviews.

RESULTS

The app was used by 52% of 315 patients studied. Younger patients were the most frequent users. Patients with better treatment compliance used the app more, although data collection was incomplete for most patients. The best rated by patients were the reminders of days of administration and the minimum stock alerts at home. Healthcare professionals rated the app positively.

CONCLUSIONS

Healthcare professionals valued the app as useful for managing treatment of congenital coagulopathies. Patients need support and time to use the app and improve the quality of the data entered. Patients who used the app rated it positively. The treatment compliance improved.

Pathogenesis and treatment of osteoporosis in patients with hemophilia

INTRODUCTION

Hemophilia is a rare X-linked recessive inherited bleeding disorder caused by mutations of the genes encoding coagulation factor VIII (FVIII) or IX (FIX). Patients with hemophilia (PWH) often have a high risk of osteoporosis and fractures that is usually ignored. Herein, we review the underlying mechanisms of osteoporosis and the increased risk of fractures and their treatment in patients with FVIII or FIX deficiency.

METHODS

The PubMed, Web of Science, Embase, and Cochrane Library databases were searched to identify original research articles, meta-analyses, and scientific reviews on the mechanisms or treatment of osteoporosis in PWH.

RESULTS

The pathogenic mechanisms of osteoporosis in PWH are multifactorial and remain unclear. The available evidence shows that FVIII and FIX deficiency may directly affect bone metabolism by interfering with the RANK/RANKL/OPG pathway. Other potential mechanisms of osteoporosis in PWH include thrombin deficiency and the unloading and immobilization of bone, which will affect osteoblast and osteoclast activity by changing the cytokine profiles. The treatment of osteoporosis in PWH includes antiresorptive, anabolic, and dual-action drugs; weight-bearing exercise; fall prevention; and prophylactic coagulation factor replacement therapy. However, clinical studies of the efficacy of anti-osteoporotic agents in osteoporosis of PWH are urgently needed.

CONCLUSION

This review summarizes recent progress in research on the pathogenesis of osteoporosis in PWH and provides insights into potential treatment for osteoporosis in PWH.

Increased acute care utilisation, comorbidities and mortality in adults with haemophilia: A population-based cohort study from 2012 to 2019

INTRODUCTION

Improvements in treatment strategies have led to increased life expectancy of persons with haemophilia (PWH). Consequently, age-related comorbidities become increasingly relevant.

AIM

To evaluate the prevalence of age-related comorbidities, mortality, health service utilisation and predictors of hospitalisation in PWH compared to the general population.

METHODS

We conducted a population-based retrospective cohort study using linked administrative data. Men with haemophilia were identified in Alberta, Canada (2012-2019) with a validated case definition and were age-matched with male population controls. We calculated the prevalence of major comorbidities, all-cause mortality, and examined health service utilisation including Emergency Department visits and hospitalisations. Logistic regression was applied to identify predictors of hospitalisation.

RESULTS

We identified 198 and 329 persons with moderately severe haemophilia and mild/moderate, respectively. Moderately severe haemophilia had a higher risk of death (standardised mortality ratio 3.2, 95% confidence interval [CI] 1.4-6.3) compared to the general population. PWH had a significantly higher prevalence of hypertension, liver diseases and malignancies than controls. Moderately severe haemophilia was associated with significantly higher rates of hospitalisations (52.5% vs. 14.5%), Emergency Department visits (89.1% vs. 62.7%) and intensive care admissions (8.9% vs. 2.3%). Age > 65 years (adjusted odds ratio [aOR] 6.8) and presence of multiple comorbidities (aOR 3.9) were significant predictors of hospitalisations among PWH.

CONCLUSION

Despite advanced care, haemophilia is associated with higher acute care utilisation than the general population, highlighting the substantial burden of illness on patients and the health care system.

Gene Therapy and Hemophilia: Where Do We Go from Here?

Gene therapy for hemophilia using adeno-associated virus (AAV) derived vectors can reduce or eliminate patients' disease-related complications and improve their quality of life. Broad implementation globally will lead to societal gains and foster health equity. Several vector products each for factor IX (FIX) or factor VIII (FVIII) deficiency are in advanced clinical development. Safety data are reassuring. Efficacy data for up to 8 and 5 years, respectively, vary considerably among vector types and among individuals, but indicate significant reduction in bleeds and factor use. Products will soon be approved for marketing. This review highlights the relevant considerations for implementation of hemophilia gene therapy, specifically across a broad range of socioeconomic backgrounds globally, based on recent publications and our own experience. We address the current efficacy and safety data and relevant aspects of vector immunology. We then discuss pertinent implementation steps including pre-implementation and readiness assessments, considerations on cost, cost-effectiveness and payment models, approaches to education and informed consent, and the operational needs as well as the need for monitoring of health outcomes and implementation outcomes. To prevent a lag or complete lack of establishing access to this life-changing therapy option for all patients with hemophilia worldwide, adaptable pathways supported by collaborative and international efforts of all stakeholders are needed.

Spectrum of Inherited Bleeding Disorder with Special Reference to von Willebrand Disease in Eastern India

Background The objective of this study is to study the prevalence, clinical spectrum, and hematological profile of inherited bleeding disorder with special reference to von Willebrand disease in eastern India.

Materials and Methods This prospective study was done in a tertiary care center in the eastern part of India over 2 years. Detailed history and clinical findings were noted in a proforma. Laboratory analysis included prothrombin time, activated partial thromboplastin time, bleeding time, and fibrinogen assay along with tests related to specific factor assay.

Results One hundred and five patients were diagnosed as suffering with the inherited bleeding disorder out of a total of 1,204 patients. The age of patients ranged from 13 days to 35 years. The most common presenting clinical feature was prolonged bleeding after cut (76.19%). Out of 105 patients, 97 patients (92.38%) had coagulation defect, 5 patients (4.76%) had von Willebrand disease (vWD), and 3 patients (2.85%) had platelet defect. Most common coagulation defect was hemophilia A (84 cases), followed by hemophilia B (8 cases). Other rare congenital factor deficiencies were seen in five cases (5.15%). Only platelet defect was Glanzmann's thrombasthenia (GT). The age of vWD patients ranged from 4.5 years to 24 years. Forty percent patients with vWD disease were type 1 followed by 40% of type 2N and 20% of type 3 vWD.

Conclusion vWD was not so common in eastern India. vWD was present only in 4.76% cases in this study. The most common coagulation defect was hemophilia A (86.59%) in our study. GT was present in only 2.85% cases.

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.

Compendium of causative genes and their encoded proteins for common monogenic disorders

A compendium is presented of inherited monogenic disorders that have a prevalence of >1:20,000 in the human population, along with their causative genes and encoded proteins. "Simple" monogenic diseases are those for which the clinical features are caused by mutations impacting a single gene, usually in a manner that alters the sequence of the encoded protein. Of course, for a given "monogenic disorder", there is sometimes more than one potential disease gene, mutations in any one of which is sufficient to cause phenotypes of that disorder. Disease-causing mutations for monogenic disorders are usually passed on from generation to generation in a Mendelian fashion, and originate from spontaneous (de novo) germline founder mutations. In the past monogenic disorders have often been written off as targets for drug discovery because they sometimes are assumed to be rare disorders, for which the meager projected financial payoff of drug discovery and development has discouraged investment. However, not all monogenic diseases are rare. Here, we report that that currently available data identifies 72 disorders with a prevalence of at least 1 in 20,000 humans. For each, we tabulate the gene(s) for which mutations cause the spectrum of phenotypes associated with that disorder. We also identify the gene and protein that most commonly causes each disease. 34 of these disorders are caused exclusively by mutations in only a single gene and encoded protein.

Naive haemophilia mice displayed different pattern of cytokine profiles of cytokine profiles changes might be associated with subclinical bleeding

Subclinical bleeding is a haemorrhage event not clinically detected in haemophilia, and no reliable method is available for predicting subclinical bleeding. We investigated whether haemophilia mice have subclinical haemorrhage and evaluated potential biomarkers including multiple cytokine changes to predict subclinical haemorrhage. Plasma from naïve FVIII-/- and FIX-/- mice and their wild-type counterparts (FVIII WT and FIX WT, respectively) were measured for prothrombin fragment 1 + 2 (F1 + 2) and multiple cytokines. Haemophilia mice with induced hemarthrosis were used as positive clinical bleeding controls. Naive haemophilia mice that displayed higher levels than positive bleeding control were counted. Univariate and multivariate analyses of cytokines were performed. Compared with wild-type mice (FVIII WT 1.1-6.2 vs. FIX WT 2.7-6.7 pmol/l), F1 + 2 widely varied in both haemophilia mouse strains (FVIII-/- 3.7-25.7 vs. FIX-/- 2.7-15.7 pmol/l). Each cytokine varied widely in both naive haemophilia A and B mice, but not significantly, for most cytokines. In comparison to haemophilia mice with hemarthrosis bleeding challenge, naive FVIII-/- mice had elevated pro-inflammatory cytokines and FIX-/- mice had elevated anti-inflammatory cytokines. In addition, interleukin (IL)-4, followed by IL-1, IL-6, TNF-α and MIP-1α in FVIII-/- mice and MIP-1α, followed by IL-1, IL-10 in FVIII-/- mice exhibited significant differences potentially associated with potential subclinical bleeding. Naive haemophilia mice showed elevated pro-inflammatory cytokines with different patterns, represented by pro-inflammatory cytokine elevation in more naïve FVIII-/- mice and more anti-inflammatory cytokines in FIX-/- mice.

Nonneutralizing FVIII-specific antibody signatures in patients with Hemophilia A and in healthy donors

Isotypes and IgG subclasses of nonneutralizing FVIII-specific antibodies are similar in hemophilia A patients and healthy subjects.

Prevalences, titers, and affinities of nonneutralizing antibodies, however, differ significantly between patients and healthy subjects.

Previous studies identified nonneutralizing FVIII-specific antibodies in the circulation of severe and nonsevere hemophilia A (sHA and nsHA) patients without FVIII inhibitors and also in some healthy individuals. To gain a better understanding of the nature of these nonneutralizing antibody responses, we analyzed and compared anti-FVIII antibody signatures in 3 study cohorts: previously treated sHA as well as nsHA patients without FVIII inhibitors, and healthy donors. FVIII-binding IgM, IgG1-4, and IgA antibodies were differentiated, FVIII-specificity was assessed, and associated apparent affinity constants were determined. Our results indicate that the nonneutralizing FVIII-specific antibody response in all study cohorts is dominated by IgG1 and IgA. Prevalences, titers, and affinities of these nonneutralizing antibodies were higher in the hemophilia A cohorts than in healthy donors. Stratification for the anti-hepatitis C virus (HCV) antibody status demonstrated the presence of FVIII-specific IgA with elevated titers in sHA patients with an active or past HCV infection when compared with HCV antibody-positive nsHA patients or HCV antibody-negative patients and healthy donors. Increased titers and affinities of FVIII-specific IgG1 antibodies were observed in a considerable number of hemophilia A patients as opposed to healthy subjects independently of the patients’ anti-HCV antibody status. Overall, our findings support the hypothesis that the generation of nonneutralizing anti-FVIII antibodies in healthy individuals and in noninhibitor hemophilia A patients might be based on similar immune mechanisms. However, differences in prevalences, titers, and affinities of these antibodies indicate distinct differences in the antibody evolution between healthy individuals and patients.

Deletion of Coagulation Factor IX Compromises Bone Mass and Strength: Murine Model of Hemophilia B (Christmas Disease)

Osteopenia and osteoporosis have increasingly become a recognized morbidity in those persons with hemophilia (PwH) receiving inadequate prophylactic clotting factor replacement. Animal models can control or eliminate genetic and environmental factors and allow for invasive testing not clinically permissible. Here, we describe the skeletal phenotype of juvenile and adult male mice with a genetically engineered deficiency in coagulation factor IX (FIX KO). Although the somatic growth of FIX KO mice matched that of their wild-type (WT) littermates at 10 and 20 weeks of age, the FIX KO mice displayed reduced bone mineral density (BMD), reduced cortical and cancellous bone mass, and diminished whole bone fracture resistance. These findings coupled with parallel observations in a murine model of hemophilia A (FVIII deficiency) point to an effector downstream of the coagulation cascade that is necessary for normal skeletal development. Further study of potential mechanisms underlying the bone disease observed in rare clotting factor deficiency syndromes may lead to new diagnostic and therapeutic insights for metabolic bone diseases in general.

Determining the Minimally Effective Dose of a Clinical Candidate AAV Vector in a Mouse Model of Hemophilia A

Hemophilia A, a bleeding disorder, affects 1:5,000 males and is caused by a deficiency of human blood coagulation factor VIII (hFVIII). Studies in mice and macaques identified AAVhu37.E03.TTR.hFVIIIco-SQ.PA75 as a clinical candidate gene therapy vector to treat hemophilia A. In this study, we sought to determine the minimally effective dose (MED) of this vector in a hemophilia A mouse model. Mice received one of four vector doses (3 × 10¹¹–1 × 10¹³ genome copies [GCs]/kg) via intravenous tail vein injection; one cohort received vehicle as a control. Animals were monitored daily after vector/vehicle administration. Blood samples were collected to evaluate hFVIII activity levels and anti-hFVIII antibodies. Animals were sacrificed and necropsied on days 28 and 56; tissues were harvested for histopathological examination and blood was collected for serum chemistry panel analysis. We found no significant differences in liver transaminase levels in mice administered any vector dose compared to those administered vehicle (except for one group administered 3 × 10¹¹ GC/kg). Total bilirubin levels were significantly elevated compared to the vehicle group following two vector doses at day 56 (1 × 10¹² and 1 × 10¹³ GC/kg). We observed no vector-related gross or histological findings. Most microscopic findings were in the vehicle group and considered secondary to blood loss, an expected phenotype of this mouse model. Since we observed no dose-limiting safety markers, we determined that the maximally tolerated dose was greater than or equal to the highest dose tested (1 × 10¹³ GC/kg). Since we detected hFVIII activity in all cohorts administered vector, we conclude that the MED is 3 × 10¹¹ GC/kg—the lowest dose evaluated in this study.

Health and treatment outcomes of patients with hemophilia in the Netherlands, 1972-2019

INTRODUCTION

We conducted six cross-sectional nationwide questionnaire studies among all patients with hemophilia in the Netherlands from 1972 until 2019 to assess how health outcomes have changed, with a special focus on patients >50 years of age.

METHODS

Data were collected on patient characteristics, treatment, (joint) bleeding, joint impairment, hospitalizations, human immunodeficiency virus and hepatitis C infections, and general health status (RAND-36).

RESULTS

In 2019, 1009 patients participated, of whom 48% had mild, 15% moderate, and 37% severe hemophilia. From 1972 to 2019, the use of prophylaxis among patients with severe hemophilia increased from 30% to 89%. Their median annual bleeding rate decreased from 25 to 2 bleeds. Patients with severe hemophilia aged <16 years reported joint impairment less often over time, but in those aged >40 years joint status did not improve. In 2019, 5% of all 1009 patients were positive for the human immunodeficiency virus. The proportion of patients with an active hepatitis C infection drastically decreased from 45% in 2001 to 2% in 2019 due to new anti-hepatitis C treatment options. Twenty-five percent had significant liver fibrosis even after successful therapy. Compared to the general male population, patients aged >50 years reported much lower scores on the RAND-36, especially on physical functioning.

DISCUSSION/CONCLUSION

Our study shows that increased use of prophylactic treatment and effective hepatitis C treatment have improved joint health and nearly eradicated hepatitis C infection in patients with hemophilia in the Netherlands. However, patients still suffer from hemophilia-related complications, especially patients aged >50 years.

Patient preferences in the treatment of hemophilia A: A latent class analysis

OBJECTIVE

To examine subgroup-specific treatment preferences and characteristics of patients with hemophilia A.

METHODS

Best-Worst Scaling (BWS) Case 3 (four attributes: application type; bleeding frequencies/year; inhibitor development risk; thromboembolic events of hemophilia A treatment risk) conducted via online survey. Respondents chose the best and the worst option of three treatment alternatives. Data were analyzed via latent class model (LCM), allowing capture of heterogeneity in the sample. Respondents were grouped into a predefined number of classes with distinct preferences.

RESULTS

The final dataset contained 57 respondents. LCM analysis segmented the sample into two classes with heterogeneous preferences. Preferences within each were homogeneous. For class 1, the most decisive factor was bleeding frequency/year. Respondents seemed to focus mainly on this in their choice decisions. With some distance, inhibitor development was the second most important. The remaining attributes were of far less importance for respondents in this class. Respondents in class 2 based their choice decisions primarily on inhibitor development, also followed, by some distance, the second most important attribute bleeding frequency/year. There was statistical significance (P < 0.05) between the number of annual bleedings and the probability of class membership.

CONCLUSIONS

The LCM analysis addresses heterogeneity in respondents' choice decisions, which helps to tailor treatment alternatives to individual needs. Study results support clinical and allocative decision-making and improve the quality of interpretation of clinical data.

Haemophilia

Haemophilia A and B are rare congenital, recessive X-linked disorders caused by lack or deficiency of clotting factor VIII (FVIII) or IX (FIX), respectively. The severity of the disease depends on the reduction of levels of FVIII or FIX, which are determined by the type of the causative mutation in the genes encoding the factors (F8 and F9, respectively). The hallmark clinical characteristic, especially in untreated severe forms, is bleeding (spontaneous or after trauma) into major joints such as ankles, knees and elbows, which can result in the development of arthropathy. Intracranial bleeds and bleeds into internal organs may be life-threatening. The median life expectancy was ~30 years until the 1960s, but improved understanding of the disorder and development of efficacious therapy based on prophylactic replacement of the missing factor has caused a paradigm shift, and today individuals with haemophilia can look forward to a virtually normal life expectancy and quality of life. Nevertheless, the potential development of inhibitory antibodies to infused factor is still a major hurdle to overcome in a substantial proportion of patients. Finally, gene therapy for both types of haemophilia has progressed remarkably and could soon become a reality.

The risk of venipuncture in newborn with severe hemophilia: Case report of a large elbow hemorrhage and literature review of compartment syndrome

Hemophilias are hemorrhagic congenital rare diseases. The gold standard of therapy in hemophilics is the intravenously replacement therapy. We can infuse intravenously plasma derived factors (FVIII for Hemophilia A and FIX for Hemophilia B) or recombinant products (i.e. clotting factor synthetically produced). Venipuncture is not a safe procedure in subjects with hemorrhagic diseases. It is considered an invasive technique with potential massive bleeding and it requires standardized procedures to prevent complications. Local pressure after the procedure (with eventually ice rest) must be always done. In case of bleeding a rapid replacement therapy must be conducted. A severe complication in hemophilia is compartment syndrome. We report a case of massive bleeding in a hemophilic newborn after venipuncture and a literature review of compartment syndrome in hemophiliacs. The aim of this paper is to help physicians in the clinical management to prevent the evolution of a massive bleeding in compartment syndrome.

Development and validation of a case definition to identify hemophilia in administrative data

INTRODUCTION

Administrative data is useful in population-based studies in hemophilia, but few studies validated the coding accuracy.

AIM

We validated the accuracy of a case definition using a combination of International Classification of Diseases diagnostic codes and coagulation factor level for identifying hemophilia in administrative data.

METHODS

This is a retrospective population-based study of all residents of Alberta, Canada, who underwent testing for coagulation factor VIII (FVIII) or factor IX (FIX) activity between 2009 and 2017 using linked administrative data. Our predefined algorithm was a combination of the relevant ICD codes and FVIII/FIX activity <0.4 IU/ml. Medical charts of 2114 randomly selected patients tested for FVIII and 528 patients tested for FIX were reviewed to identify physician diagnoses of hemophilia. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) were calculated.

RESULTS

With our algorithm, 72 (3.4%) patients tested for FVIII and 21 (4.0%) tested for FIX met the combined ICD code and laboratory criteria for hemophilia A and hemophilia B, respectively, whereas 63 (3.0%) and 22 (4.2%) had confirmed hemophilia A and hemophilia B upon chart review. Our algorithm had a sensitivity of 93.7% and specificity of 99.4% for identifying hemophilia A, and a sensitivity of 90.9% and specificity of 99.8% for identifying hemophilia B.

CONCLUSION

This study showed that using a case definition of ICD codes and coagulation factor activities can identify hemophilia in administrative data with very high accuracy and can be used for future research.

Development and Validation of a Population-Pharmacokinetic Model for Rurioctacog Alfa Pegol (Adynovate®): A Report on Behalf of the WAPPS-Hemo Investigators Ad Hoc Subgroup

BACKGROUND AND OBJECTIVE

Rurioctacog alfa pegol (Adynovate) is a modified recombinant factor VIII concentrate used for treating hemophilia A. Aiming to improve treatment tailoring on the Web-Accessible Population Pharmacokinetic Service-Hemophilia (WAPPS-Hemo) platform for patients of all ages treated with Adynovate, we have developed and evaluated a population pharmacokinetic (PopPK) model. On the platform, PopPK models are used as priors for Bayesian forecasting that derive individual PK of hemophilia patients and are subsequently used for personalized dose regimen design.

METHODS

Factor activity measurements and demographic covariate data from patients infused with Adynovate were extracted from the WAPPS-Hemo database. Evaluations testing the appropriateness of Bayesian forecasting included 10-fold cross validation, a limited sampling analysis (LSA), and an external evaluation using additional independent data extracted from the WAPPS-Hemo database at a later date.

RESULTS

The model was constructed using 650 plasma factor activity observations (555 one stage assay and 95 chromogenic assay - 4.6% below limit of quantification) measured in 154 patients from 36 hemophilia centres. A two-compartment model including between subject variability on clearance and central volume was selected as the base model. Covariates were fat free mass on clearance and central volume, age on clearance and assay type on activity. The final model was well-suited to predict PK parameters of new individuals (n = 26) from sparse observations.

CONCLUSIONS

The development of a PopPK model for Adynovate using real-world data increases the covariate space (e.g. age) beyond what is possible from clinical trial data. This model is available on the WAPPS-Hemo platform for tailoring treatment in hemophilia A patients.

Morphological variation of the hemophilic talus

Flattening of the trochlear tali is clinically observed as structural and functional changes advance in patients with hemarthropathy of the ankle. However, the degree of this flattening has not yet been quantified, and distribution of the morphological changes across the talus not yet defined. Chronologically sequential MR images of both a hemophilic patient group (N = 5) and a single scan from a nondiseased, sex-matched, control group (N = 11) were used to take four measurements of the trochlear talus morphology at three locations (medial, central and lateral) along the sagittal plane. Three ratios of interest were defined from these to assess whether the talar dome flattens with disease. The control group MRI measurements were validated against literature data obtained from CT scans or planar X-Rays. The influence of disease on talar morphology was assessed by direct comparison of the hemophilic cases with the control group. The values for all three ratios, in all locations, differed between the control and the hemophilic group. Flattening was indicated in the hemophilic group in the medial and lateral talus, but differences in the central talus were not statistically significant. This work demonstrates that morphological assessment of the talus from MR images is similar to that from CT scans or planar X-Rays. Talar flattening does occur with hemarthropathy, especially at the medial and lateral edges of the joint surface. General flattening of the trochlear talus was confirmed in this small patient sample, however the degree and rate of change is unique to each ankle.

Association between reported medication adherence and health-related quality of life in adult patients with haemophilia

Background Medication adherence is an important issue, not just health-related, for patients with haemophilia. Poor medication adherence to long-term therapies limits the potential of effective treatments to improve patients' health-related quality of life. Objective The aim of this study was to investigate the association of reported medication adherence and health-related quality of life in patients with haemophilia. Setting Data were collected from patients at University Hospital Centre Zagreb, Croatia and at University Medical Centre Ljubljana, Slovenia. Method Adult male patients with severe or moderate haemophilia receiving prophylactic treatment were eligible for the study. Main outcome measure Implementation phase of medication adherence was assessed with the self-reported VERITAS-Pro instrument and health-related quality of life with SF-36v2. Results A total of 82 participants were included in the study (median age was 44.50, range 18-73 years). The majority of our participants reported being adherent to medication (83%). Participants showed better health in the mental health domains and Mental Component Summary than in the physical health domains and Physical Component Summary. After controlling for demographic, socioeconomic and clinical predictors, better reported medication adherence explained an additional 4-6% of better health variance in Bodily Pain and Social Functioning domains and Mental Component Summary. Conclusion We found that reported medication adherence can contribute to better health-related quality of life in patients with haemophilia. Since life with a chronic condition is demanding, it is an important finding that medication adherence to replacement therapy can improve life conditions for patients with haemophilia.

Maternal and neonatal bleeding complications in relation to peripartum management in hemophilia carriers: A systematic review

Currently, there is no consensus on the optimal management to prevent postpartum hemorrhage (PPH) in hemophilia carriers. We aimed to evaluate peripartum management strategies in relation to maternal and neonatal bleeding outcomes by performing an extensive database search up to August 2020. Seventeen case-reports/series and 11 cohort studies were identified of overall 'poor' quality describing 502 deliveries. The PPH incidence in the individual patient data was 63%; 44% for those women receiving prophylaxis to correct coagulation and 77% for those without (OR 0.23, CI 0.09-0.58) and in cohort data 20.3% (26.8% (11/41) vs. 19.4% (55/284) (OR: 1.53, 95% CI: 0.72-3.24), respectively. Peripartum management strategies mostly consisted of clotting factor concentrates, rarely of desmopressin or plasma. Tranexamic acid appears promising in preventing secondary PPH, but was not used consistently. Neonatal bleeding was described in 6 affected male neonates, mostly after instrumental delivery or emergency CS, but insufficient information was provided to reliably investigate neonatal outcome in relation to management. The high PPH risk seems apparent, at most mildly attenuated by prophylactic treatment. Prospective cohort studies are needed to determine the optimal perinatal management in hemophilia.

Delivery and neuraxial technique outcomes in patients with hemophilia and in hemophilia carriers: a systematic review

Female carriers are more common than males with hemophilia and unrecognized factor VIII or IX deficiency is associated with intrauterine growth retardation, epidural hematomas, blood transfusion, and peripartum hemorrhage. A review was conducted to assess the evidence for professional society recommendations for > 50% factor levels during labor. Two searches of Pubmed, CINAHL, Cochrane, and Google Scholar were completed in October 2019. The first for case reports and series described neuraxial techniques in patients with hemophilia-regardless of sex, age, or pregnant status. The second for case reports and series described bleeding outcomes of parturients with hemophilia. Primary outcomes were diagnosis of neuraxial hematoma (first search) and postpartum bleeding complications (second search). Thirteen articles (n = 134) described neuraxial techniques in patients with hemophilia. Neuraxial hematoma with paraplegia occurred in 3/134 patients-all had a factor level of 1%. Nineteen articles (2712 deliveries in 2657 women) described bleeding outcomes. Postpartum hemorrhage occurred in 7.1% (193/2712) of deliveries, of which 60% necessitated blood transfusion. Postpartum bleeding complications were twice as likely (51.0% [25/49] vs. 25.6% [52/203], P < 0.001) with factor activity < 50%. Therefore, factor levels should be assessed and increased above 50% prior to neuraxial technique and delivery.Trial registration: PROSPERO 2018 CRD42018110215.

Long-Term Outcomes of Previously Treated Adult and Adolescent Patients with Severe Hemophilia A Receiving Prophylaxis with Extended Half-Life FVIII Treatments: An Economic Analysis from a United Kingdom Perspective

Background

The standard of care for patients with hemophilia A is prophylaxis with factor VIII (FVIII) therapies. Extended half-life (EHL) FVIII products offer a reduced infusion burden compared with standard FVIII treatments. However, comparative evidence between EHLs is lacking.

Objective

To develop a pharmacodynamic–pharmacokinetic decision model to predict comparative bleed outcomes of adolescents and adults with hemophilia A receiving treatment with various EHL FVIII therapies, capturing differences in cumulative bleeding episodes, breakthrough bleed resolution and resource costs, as well as quality-adjusted life years (QALYs).

Methods

The patient population from the pathfinder 2 Phase III clinical trial was used to understand the link between FVIII levels and annual bleeding rates (ABRs). Pharmacokinetic/pharmacodynamic modeling was subsequently applied to estimate FVIII levels for four EHL FVIII treatments (turoctocog alfa pegol [Esperoct^®], rurioctocog alfa pegol [Adynovi^®], efmoroctocog alfa [Elocta^®], and damoctocog alfa pegol [Jivi^®]) to predict comparative ABRs. FVIII consumption costs (due to prophylactic treatment and breakthrough bleed resolution) and resource costs, as well as QALYs, were subsequently estimated from a UK NHS perspective over a 70-year time horizon.

Results

Turoctocog alfa pegol prophylaxis resulted in 8–19% fewer cumulative bleeding episodes versus comparators in the base case scenario. Assuming parity in annual prophylaxis costs, turoctocog alfa pegol prophylaxis reduced the cost of product and resource use to resolve a breakthrough bleed by 9–25% versus comparators. Prophylaxis with turoctocog alfa pegol was also associated with the most QALYs, representing a discounted QALY gain of 0.35–1.05 compared with the other treatments.

Conclusion

Using a pharmacodynamic–pharmacokinetic decision model, turoctocog alfa pegol prophylaxis was associated with fewer cumulative bleeds, as well as lower product and resource costs related to resolving a breakthrough bleed and most QALYs versus comparators.

Budget impact analysis of Jivi (damoctocog alfa pegol, Bay 94-9027) in severe hemophilia A in Japan

OBJECTIVE

Hemophilia A (HA) is a genetic bleeding disorder characterized by a deficiency of clotting factor VIII (FVIII) requiring lifelong prophylactic treatment typically with conventional standard half-life recombinant FVIII (rFVIII). Lifelong prophylaxis impacts budget, patient adherence, and long-term outcomes. The consequent economic and treatment burden may be reduced by using novel extended half-life rFVIII. The objective of this analysis was to estimate the budget impact of introducing Jivi (damoctocog alfa pegol, BAY 94-9027), hereafter referred to as BAY 94-9027, as an on-demand and prophylactic treatment for severe HA from a Japanese payer's perspective.

METHODS

A global budget impact model was adapted to the Japanese setting using data obtained via a targeted literature review of Japanese sources. The model considered a five-year time horizon for a market without and with BAY 94-9027. Using annual per-patient costs, the total cost of on-demand and prophylactic treatment of adolescent and adult patients with severe HA (without inhibitors) were analyzed. The model used summary of product characteristics (SmPC) and clinical trial dosing, and unit costs from the National Health Insurance (NHI) drug price database. Comparators considered in the model comprised of currently available products in Japan. Projected BAY 94-9027 uptake ranged from 4% to 9% over the five years (2020-2024).

RESULTS

Introduction of BAY 94-9027 for the treatment of severe HA is estimated to decrease the overall budget by 1.5%, with a cost saving of approximately $67 million USD (¥7.4 billion JPY) over five years. Estimated cost savings associated with BAY 94-9027 ranged from $1.4 million USD (¥156 million JPY) in 2020 to $23 million USD (¥2.6 billion JPY) in 2024 for the Japanese healthcare system.

LIMITATIONS

There were limitations associated with the study. The Japanese guidelines consulted during the targeted literature review of national data sources in Japan were based on global data as reference sources. Also, studies reporting the bleeding rate, dosing guidelines, and economic burden in the Japanese population identified by the targeted literature review were limited hence global studies were used and may not have been representative of the Japanese population.

CONCLUSIONS

BAY 94-9027 can reduce total severe HA treatment costs, driven by lower annual rFVIII utilization, and a narrow weekly dosing range compared to competitor products in the Japanese market.

The Need for Comprehensive Care for Persons with Chronic Immune Thrombocytopenic Purpura

Chronic platelet disorders (CPD), including chronic immune thrombocytopenic purpura (cITP), thrombotic thrombocytopenic purpura (TTP) and platelet function disorders are among the most common bleeding disorders and are associated with morbidity and mortality. The clinical phenotype and complexity of cITP is much like that of hemophilia. In cITP and hemophilia, bleeding is problematic for many, complicating employability, insurability and overall quality-of-life (QoL). While myriad drug therapies are available for cITP and hemophilia, each are variable in their effectiveness, very few (except for clotting factor concentrates for hemophilia) alter the natural history of the disorder and sometimes contribute to specific morbidities and mortality. Like in hemophilia, the management of cITP is not solely based on access to effective treatment but also includes accurate diagnosis and comprehensive care by a multidisciplinary team of specialists trained in the management of bleeding disorders. The model of comprehensive care in Hemophilia Treatment Centers (HTCs) has been recognized as highly effective, improving life expectancy for persons with hemophilia. cITP, and other CPDs, are complex disorders requiring specialized care. However, an integrated care model with a systematic and reliable population-based surveillance program does not exist. Extending the Comprehensive Care model with all its related benefits to the community of persons with cITP is sorely needed. This review will focus on cITP as a prototype chronic platelet disorder that could benefit greatly from the Comprehensive Care model.

Identification of the Intron 22 and Intron 1 Inversions of the Factor VIII Gene in Iraqi Kurdish Patients With Hemophilia A

Hemophilia A (HA) is a severe coagulation disorder affecting 1 in 5000 to 10 000 male births. In severe cases, the most deleterious large DNA rearrangements are inversions of intron 22 (Inv22) and intron 1 (Inv1) of the factor VIII (FVIII) gene. These account for 40% to 50% and 1% to 5% of all causative mutations, respectively. Nevertheless, no genetic analysis to identify the actual causative mutation of FVIII, particularly Inv22 and Inv1, among Iraqi Kurdish hemophiliacs has been performed. In this study, we aimed to genotype Inv22 and Inv1 of the FVIII gene in our patients with HA and reveal the genotype/phenotype correlation with the inversion mutations and their role as a risk factor for the development of inhibitors. Analyses of the Inv22 and Inv1 mutations in 80 Iraqi Kurdish patients with HA (60 severe, 18 moderate, and 2 mild) were performed using the inverse shifting–polymerase chain reaction (IS-PCR) method. In severe cases, 46.7% (28/60) had Inv22 and 3.3% (2/60) had Inv1. The genotype/phenotype relation of Inv22 and Inv1 illustrated a statistically significant association (P = .012) between disease severity and inversion mutations. Slightly more patients with Inv22 (39%) developed inhibitors than those without Inv22 (28%; odds ratio = 1.65, 95% confidence interval = 0.56-4.87, P = .361). Inv22 is a major cause of severe HA in Iraqi Kurdish patients, and IS-PCR is a rapid, robust, and effective method that can be applied for carrier detection and prenatal diagnosis of HA in developing countries.

Hemophilia gene therapy-New country initiatives

Gene therapy is an opportunity for haemophilia patients to receive a one-time treatment and have lasting factor levels for years or decades instead of dependence on repeated administration within short intervals and on sustained supply of drug. Great strides have been made in the development of gene therapy for haemophilia in the last decade. Adeno-associated virus (AAV) vector-mediated gene transfer in haemophilia A and B has entered the phase III trial stage. Gene transfer by lentiviral vector or gene editing technologies using factor VIII (FVIII) or IX (FIX) genes are now entering clinical evaluation. It is expected that the first FVIII and FIX gene therapy products will soon be approved and distributed in major markets. Global access to gene therapy is a critical goal. This review presents new and ongoing efforts towards this goal in countries other than North America and Europe. In Japan, researchers, regulators and funders have established a promising gene therapy development platform for multiple diseases including haemophilia. Decades of scientific and clinical research in haemophilia gene therapy in China have led to a recently registered clinical trial of AAV-mediated gene therapy for haemophilia B. Other countries are in earlier phases of building gene therapy programmes or participate in international trials. A phase 2 feasibility trial of AAV-mediated FIX gene therapy in low- and middle-income countries aims to demonstrate that gene therapy could become available in resource-constrained socio-economic settings. The different strategies for establishing gene therapy provide opportunities for closing the global gap in haemophilia care.

Impact of gene therapy for canine monogenic diseases on the progress of preclinical studies

Rapid progress in knowledge of the organization of the dog genome has facilitated the identification of the mutations responsible for numerous monogenic diseases, which usually present a breed-specific distribution. The majority of these diseases have clinical and molecular counterparts in humans. The affected dogs have thus become valuable models for preclinical studies of gene therapy for problems such as eye diseases, immunodeficiency, lysosomal storage diseases, hemophilia, and muscular dystrophy. Successful gene therapies in dogs have significantly contributed to decisions to run clinical trials for several human diseases, such as Leber's congenital amaurosis 2-LCA2 (caused by a mutation of RPE65), X-linked retinitis pigmentosa-XLRP (caused by mutation RPGR), and achromatopsia (caused by mutation of CNGB3). Promising results were also obtained for canine as follows: hemophilia (A and B), mucopolysaccharidoses (MPS I, MPS IIIB, MPS VII), leukocyte adhesion deficiency (CLAD), and muscular dystrophy (a counterpart of human Duchenne dystrophy). Present knowledge on molecular background of canine monogenic diseases and their successful gene therapies prove that dogs have an important contribution to preclinical studies.

A Molecular Revolution in the Treatment of Hemophilia

For decades, the monogenetic bleeding disorders hemophilia A and B (coagulation factor VIII and IX deficiency) have been treated with systemic protein replacement therapy. Now, diverse molecular medicines, ranging from antibody to gene to RNA therapy, are transforming treatment. Traditional replacement therapy requires twice to thrice weekly intravenous infusions of factor. While extended half-life products may reduce the frequency of injections, patients continue to face a lifelong burden of the therapy, suboptimal protection from bleeding and joint damage, and potential development of neutralizing anti-drug antibodies (inhibitors) that require less efficacious bypassing agents and further reduce quality of life. Novel non-replacement and gene therapies aim to address these remaining issues. A recently approved factor VIII-mimetic antibody accomplishes hemostatic correction in patients both with and without inhibitors. Antibodies against tissue factor pathway inhibitor (TFPI) and antithrombin-specific small interfering RNA (siRNA) target natural anticoagulant pathways to rebalance hemostasis. Adeno-associated virus (AAV) gene therapy provides lasting clotting factor replacement and can also be used to induce immune tolerance. Multiple gene-editing techniques are under clinical or preclinical investigation. Here, we provide a comprehensive overview of these approaches, explain how they differ from standard therapies, and predict how the hemophilia treatment landscape will be reshaped.

Changes in Muscle Activity Patterns and Joint Kinematics During Gait in Hemophilic Arthropathy

Hemophilic arthropathy is the result of repetitive intra-articular bleeding and synovial inflammation. In people with hemophilic arthropathy (PWHA), very little is known about the neural control of individual muscles during movement. The aim of the present study was to assess if the neural control of individual muscles and coordination between antagonistic muscle pairs and joint kinematics during gait are affected in PWHA. Thirteen control subjects (CG) walked overground at their preferred and slow velocity (1 m/s), and 14 PWHA walked overground at the preferred velocity (1 m/s). Joint kinematics and temporal gait parameters were assessed using four inertial sensors. Surface electromyography (EMG) was collected from gluteus maximus (GMAX), gluteus medius (GMED), vastus medialis (VM), vastus lateralis (VL), rectus femoris (RF), medial gastrocnemius (MG), lateral gastrocnemius (LG), soleus (SOL), tibialis anterior (TA), semitendinosus (ST), and biceps femoris (BF). Waveforms were compared using the time-series analysis through statistical parametric mapping. In PWHA compared to CG, EMG amplitude during the stance phase was higher for LG (for both velocities of the CG), BF (slow velocity only), and ST (preferred velocity only) (p < 0.05). Co-contraction during the stance phase was higher for MG-TA, LG-TA, VL-BF, VM-ST, LG-VL, and MG-VM (both velocities) (p < 0.05). MG and LG were excited earlier (preferred velocity only) (p < 0.05). A later offset during the stance phase was found for VL, BF, and ST (both velocities), and BF and GMAX (preferred velocity only) (p < 0.05). In addition, the range of motion in knee and ankle joints was lower in PWHA (both velocities) and hip joint (preferred velocity only) (p < 0.05). In conclusion, the neural control of individual muscles and coordination between antagonistic muscles during gait in PWHA differs substantially from control subjects.

Inherited coagulation disorders in Turkish children: A retrospective, single-center cohort study

OBJECTIVE

This study aims to investigate the distribution, clinical characteristics and outcome of inherited coagulation disorders (ICD) in Turkish children.

SUBJECTS AND METHODS

Data from all children (age<18 years) with ICD examined in our center were retrospectively reviewed.

RESULTS

There were 403 children with ICD (233 males and 170 females) with a median age of four years at diagnosis. The percentages of von Willebrand disease (vWd), hemophilia and rare bleeding disorders (RBD) were 40 %, 34 % and 26 %, type-1, type-2 and type-3 vWd were 63 % 17 % and 20 %, hemophilia A and B were 84 % and 16 %, and severe, moderate and mild hemophilia were 48 %, 30 % and 22 %, respectively. Factor VII and FXI deficiencies were the most prevalent, comprising 56 % and 22 % of all children with RBD, respectively. Parental consanguinity rates were 72 % in type-3 vWd and 61 % in severe RBD. The overall prevalence of gastrointestinal bleedings was 4.5 % (18/403), intracranial bleeding (ICB) was 4.96 % (20/403), mortality from ICB was 30 % (6/20) and the overall mortality rate was 1.49 % (6/403). No life-threatening bleeding was seen during regular prophylaxis. Chronic arthropathy prevalence in severe hemophilia was 8 % with primary prophylaxis and 53 % with demand therap. Inhibitor prevalence was 14 % in hemophilia-A and 5 % in hemophilia-B.

CONCLUSIONS

These data show that vWd is the most common ICD, type-3 vWd and RBD are prevalent due to frequent consanguineous marriages and diagnosis of ICD is substantially delayed in Turkish children. Prophylactic replacement therapy prevents occurrence of life-threatening bleedings and reduces the development of hemophilic arthropathy.

Transfusion-transmitted infections in hemophilia patients who underwent surgical treatment: a study from a single center in north China

INTRODUCTION

Transfusion-transmitted infections (TTIs) continue to be a major challenge among hemophilia patients. This study was conducted to investigate the prevalence of TTIs including hepatitis B virus (HBV), hepatitis C virus (HCV), human immunodeficiency virus (HIV) and syphilis in patients with hemophilia who received surgical treatment due to bone or joint lesions in the Department of Orthopedics.

MATERIAL AND METHODS

The present study was conducted from July 1996 to November 2016 in Beijing, China. A total of 189 patients who underwent orthopedic procedures were enrolled. Blood samples were obtained from the patients and were tested for hepatitis B surface antigen (HBsAg), hepatitis C virus antibody (HCV Ab) and human immunodeficiency virus antibody (HIV Ab).

RESULTS

Among 189 hemophilia patients included in the study, 54 (28.6%) tested positive for TTI. Seroprevalence for HBsAg was found in 8 (4.2%) cases, HCV Ab in 48 (25.4%) cases, HIV Ab in 2 (1.1%) cases, and syphilis in 1 (0.5%) case. No statistically significant difference in the numbers of patients with positive HCV Ab was seen between hemophilia A (26.0%) and B (20.0%) (p = 0.786). The seroprevalence of HCV Ab (12.1%) in 66 hemophilia patients diagnosed after 1995 was significantly lower than that (32.5%) among hemophilia patients diagnosed before or in 1995 (p = 0.003).

CONCLUSIONS

Though few patients have become positive for HBsAg and HIV Ab, HCV is still the major virus of concern for hemophiliacs who have undergone orthopedic procedures. Hepatitis B vaccination should be given to the high-risk population including hemophilia patients as soon as possible.

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.

Epidemiological Profile of Hemophilia in Baghdad-Iraq

Hemophilia is an inherited bleeding disorder that mainly affects males. Globally, there are about 400 000 people with hemophilia and only 25% of them receive adequate treatment. There is insufficient epidemiological data on hemophilia in Iraq; so, this study was conducted to determine the trend of the prevalence and incidence and to identify certain clinical and epidemiological characteristics of patients with hemophilia in Baghdad, Iraq, 2016. This cross-sectional study was conducted in the 4 hemophilia centers in Baghdad. The data were compiled by reviewing all hemophilia patients’ records and the centers’ registry books between 2007 and 2016. Corresponding population data of Baghdad were obtained from the Ministry of Health. The total number of currently registered patients who are residents of Baghdad was 654. The prevalence of hemophilia increased from 7.2/100 000 males in 2007 to 15.9/100 000 males in 2016. Similarly, the incidence of hemophilia had increased from 8.4/100 000 livebirths in 2007 to 16.3/100 000 livebirths in 2016. Severe hemophilia represented 63.4% of all types. The prevalence of hepatitis C virus (HCV), hepatitis B virus (HBV), and HIV infections were 22.9%, 0.9%, and 0.2%, respectively. Clotting factor inhibitors were positive in 11.6% and target joints were found among 45.1% of patients. About 27% were on prophylactic therapy. Only one death was recorded in 2016. The prevalence and incidence of hemophilia in Baghdad was doubled in 10-year period. The prevalence of different complications was almost close to the rates in the neighboring countries.

Selection of Blood, Blood Components, and Blood Products as Essential Medicines in 105 Low- and Middle-Income Countries

Blood products of human origin are essential treatment options for several diseases, for example, hemophilia. We studied the alignment of national essential medicines lists (NEMLs) of low- and middle-income countries (LMICs) with the World Health Organization (WHO) Model List for the selection of blood products of human origin. The most recent versions of NEMLs from all LMICs were studied for the inclusion of blood products of human origin (blood and blood components, plasma products, and immunoglobulins). Data obtained from 105 NEMLs were compared to the 2017 WHO Model List. The median number of blood products of human origin on the NEMLs was 4 (range: 0-10). Immunoglobulins were most frequently included (73%). Blood and blood components were the least selected products (15%). The uptake of plasma products was around 50%. Nine countries did not have any blood products of human origin on their NEMLs. Some NEMLs included blood products not listed on the WHO Model List (albumin, hepatitis A immunoglobulin, and cryoprecipitate). We observed variation in selection according to WHO region, income level, and year of NEML update. Alignment of NEMLs with the WHO Model List varied greatly for different groups of blood products, ranging from good uptake for immunoglobulins, reasonable uptake for plasma products, to poor uptake for blood and blood components. This heterogeneity in selection and inclusion of blood products of human origin on NEMLs may be partly explained as being due to specific country characteristics, but some of it may not be explained. Policy makers need to rely on evidence in making decisions about which blood products to select, include, and remove on their NEMLs.

Hemophilia A ameliorated in mice by CRISPR-based in vivo genome editing of human Factor VIII

Hemophilia A is a monogenic disease with a blood clotting factor VIII (FVIII) deficiency caused by mutation in the factor VIII (F8) gene. Current and emerging treatments such as FVIII protein injection and gene therapies via AAV-delivered F8 transgene in an episome are costly and nonpermanent. Here, we describe a CRISPR/Cas9-based in vivo genome editing method, combined with non-homologous end joining, enabling permanent chromosomal integration of a modified human B domain deleted-F8 (BDD-F8) at the albumin (Alb) locus in liver cells. To test the approach in mice, C57BL/6 mice received tail vein injections of two vectors, AAV8-SaCas9-gRNA, targeting Alb intron 13, and AAV8-BDD-F8. This resulted in BDD-F8 insertion at the Alb locus and FVIII protein expression in the liver of vector-, but not vehicle-, treated mice. Using this approach in hemophilic mice, BDD-F8 was expressed in liver cells as functional human FVIII, leading to increased plasma levels of FVIII and restoration of blood clotting properties in a dose-dependent manor for at least 7 months, with no detectable liver toxicity or meaningful off-target effects. Based on these findings, our BDD-F8 genome editing approach may offer an efficacious, long-term and safe treatment for patients with hemophilia A.

Risk of osteoporotic fractures as a consequence of haemophilia: A nationwide population-based cohort study

AIM

Low bone mineral density occurs more commonly in patients with haemophilia (PWH) than the general population. However, the risk of haemophilia-related osteoporotic fractures has not been well established. We aim to explore the relationship between haemophilia and the development of osteoporotic fractures following haemophilia.

METHODS

This was a nationwide population-based cohort study based on the data in the Taiwan National Health Insurance Research Database (TNHIRD). Patients who were diagnosed with haemophilia were selected. A comparison cohort was formed of patients without haemophilia who were matched according to age and sex. The incidence rate and the hazard ratios (HRs) of new-onset osteoporotic fractures were calculated for both cohorts.

RESULTS

The haemophilia cohort consisted of 75 patients, and the comparison cohort comprised 300 matched control patients without haemophilia. The risk of osteoporotic fractures was higher in the haemophilia cohort than in the comparison cohort (HR = 5.41, 95% confidence interval [CI] = 2.42-12.1, P < 0.001). After adjustments for age, sex, comorbidities, urbanizations and socio-economic status, PWH were 4.37 times more likely to develop osteoporotic fractures (95% CI = 1.88-10.17, P = 0.001) as compared to matched cohort. In addition, the incidence of newly diagnosed osteoporotic fractures was significantly increased after 5-year follow-up durations.

CONCLUSION

Though our study by TNHIRD presented methodologic flaws by its design nature, we observed that haemophilia may increase the risk of osteoporotic fractures and the cumulative incidence was significantly higher for PWH diagnosed more than 5 years. Clinicians should pay particular attention to osteoporotic fractures following haemophilia in PWH as they age.