Haemophilia

Gene Therapy in Hemophilia A: Achievements, Challenges, and Perspectives

Strides in advancements of care of persons with hemophilia include development of long-acting factor replacement therapies, novel substitution and hemostatic rebalancing agents, and most recently approved gene therapy. Several decades of preclinical and clinical trials have led to development of adeno-associated viral (AAV) vector-mediated gene transfer for endogenous production of factor VIII (FVIII) in hemophilia A (HA). Only one gene therapy product for HA (valoctocogene roxaparvovec) has been approved by regulatory authorities. Results of valoctocogene roxaparvovec trial show significant improvement in bleeding rates and use of factor replacement therapy; however, sustainability and duration of response show variability with overall decline in FVIII expression over time. Further challenges include untoward adverse effects involving liver toxicity requiring immunosuppression and development of neutralizing antibodies to AAV vector rendering future doses ineffective. Real-life applicability of gene therapy for HA will require appropriate patient screening, infrastructure setup, long-term monitoring including data collection of patient-reported outcomes and innovative payment schemes. This review article highlights the success and development of HA gene therapy trials, challenges including adverse outcomes and variability of response, and perspectives on approach to gene therapy including shared decision-making and need for future strategies to overcome the several unmet needs.

Patient Perspective on Disease Burden and Gene Therapy for Hemophilia A and B: The "Haemvolution for Patients" Italian Survey

Hemophilia is a rare X-linked congenital bleeding disorder due to a deficiency of factor VIII (hemophilia A [HA]) or factor IX (hemophilia B [HB]). Replacement and nonreplacement treatments are available but have limitations. Gene therapy (GT) provides an effective, long-term, single-dose treatment option, now approaching clinical practice. This study aimed to understand patient perspectives on GT for HA and HB in Italy using a qualitative questionnaire distributed through Italian patient associations, addressing patient views on daily life, treatments, unmet needs, quality of life (QoL), and GT for hemophilia. In total, 141 participants had HA, and 14 had HB (severe 78.6%). Daily life was most affected by pain and/or joint function limitations (57.5% of participants), high infusion frequency (42.5%), management of breakthrough bleeding episodes (40.3%), and anxiety/fear of severe or sudden bleeding (38.8%). Despite current treatments, about half of the participants experienced three or more annual bleeding episodes. Most participants knew of GT (87.2%) and expected improvements in QoL (60.5%), reduced frequency of current treatments (53.5%), and a permanent cure (49.1%); 46.4% were unaware of its once-off dosage and 46.4% were not concerned about the costs they anticipated to be associated with GT. Although several fears were reported, 25.0% of participants were willing to undergo GT with the support of a multidisciplinary team. This survey provided valuable insight into patient perspectives on hemophilia and GT in Italy. Overall, relevant proportions of patients still experience limitations affecting their daily life. Most were positive about GT and anticipated improvements in their clinical outcomes and QoL.

A Case Report of Cryoneurolysis With Factor VIII Administration for Cerebral Palsy-related Spasticity in a Patient With Hemophilia A

Spasticity affects up to 80% of individuals with cerebral palsy and can lead to pain and difficulties with performing activities of daily living. If left untreated, spasticity can progress to contracture and neuro-orthopedic deformities. Cryoneurolysis is an emerging and mini-invasive ultrasound-guided technique that causes secondary axonotmesis of peripheral nerves through the formation of an ice ball and may result in months to years of improved range of motion and reduced pain in patients with spasticity. However, the safety of cryoneurolysis has not yet been established in patients with an increased bleeding risk secondary to Hemophilia A. We present a case of cryoneurolysis for cerebral palsy-related spasticity in a 14-year-old male with hemophilia A who previously had minimal benefit from botulinum toxin for increased elbow and wrist flexor tone with contracture. Fifteen minutes prior to cryoneurolysis, an IV infusion of 2000 IU of recombinant antihemophilic factor (FVIII) was administered for bleeding prophylaxis. Targets were identified with ultrasound guidance and nerve stimulation and cryoneurolysis was performed without bleeding complications or adverse events. There was an immediate improvement in tone and range of motion that was maintained at 3- and 8-month follow-ups with reported increased left arm function. This case suggests that cryoneurolysis is an effective mini-invasive procedure for spasticity that improves tone and range of motion and is safe for use in patients with Hemophilia A who receive adequate Factor VIII prophylaxis.

Patient and Caregiver Preferences for Hemophilia A Treatment in Taiwan: A Discrete Choice Experiment

OBJECTIVES

This study evaluated the treatment preferences among patients and caregivers for moderate or severe hemophilia A in Taiwan.

METHODS

This cross-sectional study used a discrete choice experiment approach to assess treatment preferences among patients with hemophilia A and their caregivers. Respondents chose between 2 hypothetical treatments defined by 7 attributes including no bleeding episode, treated events of joint bleeding, long-term safety, type of treatment and risk of thromboembolic events, administration frequency, consumption route, and monitoring dosing options. Preference weights and relative importance (RI) of attributes were estimated using a hierarchical Bayesian logistic regression model.

RESULTS

A total of 51 eligible respondents completed the discrete choice experiment (patients, 76.5%; caregivers, 23.5%). Most patients (70.6%) had severe hemophilia and 43.1% received prophylactic treatment for >10 years. Respondents valued "type of treatment and risk of thromboembolic events" as the most important factor (RI 26.2%; 95% CI 20.9-31.5) followed by "consumption route" (RI 25.8%; 95% CI 20.7-30.9) and "administration frequency" (RI 15.2%; 95% CI 12.0-18.4). "Monitoring dosing options" was the least important attribute (RI 6.3%; 95% CI 5.2-7.4). Respondents had 63% possibility to choose a treatment profile that has factor VIII product compared with nonfactor product.

CONCLUSIONS

Patients and caregivers valued "type of treatment and risk of thromboembolic events" as the most important driver in choosing a treatment for moderate or severe hemophilia A. This study provides important insights into patients' preferences and informs clinicians to consider patients' choices when prescribing a treatment.

Integrating biomarkers for hemostatic disorders into computational models of blood clot formation: A systematic review

In the pursuit of personalized medicine, there is a growing demand for computational models with parameters that are easily obtainable to accelerate the development of potential solutions. Blood tests, owing to their affordability, accessibility, and routine use in healthcare, offer valuable biomarkers for assessing hemostatic balance in thrombotic and bleeding disorders. Incorporating these biomarkers into computational models of blood coagulation is crucial for creating patient-specific models, which allow for the analysis of the influence of these biomarkers on clot formation. This systematic review aims to examine how clinically relevant biomarkers are integrated into computational models of blood clot formation, thereby advancing discussions on integration methodologies, identifying current gaps, and recommending future research directions. A systematic review was conducted following the PRISMA protocol, focusing on ten clinically significant biomarkers associated with hemostatic disorders: D-dimer, fibrinogen, Von Willebrand factor, factor Ⅷ, P-selectin, prothrombin time (PT), activated partial thromboplastin time (APTT), antithrombin Ⅲ, protein C, and protein S. By utilizing this set of biomarkers, this review underscores their integration into computational models and emphasizes their integration in the context of venous thromboembolism and hemophilia. Eligibility criteria included mathematical models of thrombin generation, blood clotting, or fibrin formation under flow, incorporating at least one of these biomarkers. A total of 53 articles were included in this review. Results indicate that commonly used biomarkers such as D-dimer, PT, and APTT are rarely and superficially integrated into computational blood coagulation models. Additionally, the kinetic parameters governing the dynamics of blood clot formation demonstrated significant variability across studies, with discrepancies of up to 1, 000-fold. This review highlights a critical gap in the availability of computational models based on phenomenological or first-principles approaches that effectively incorporate affordable and routinely used clinical test results for predicting blood coagulation. This hinders the development of practical tools for clinical application, as current mathematical models often fail to consider precise, patient-specific values. This limitation is especially pronounced in patients with conditions such as hemophilia, protein C and S deficiencies, or antithrombin deficiency. Addressing these challenges by developing patient-specific models that account for kinetic variability is crucial for advancing personalized medicine in the field of hemostasis.

Genetic Analysis and Reproductive Interventions for Two Rare Families Affected by Severe Haemophilia A

BACKGROUND

Haemophilia A (HA) is a rare bleeding disorder caused by variants in F8. Although traditional mutational analyses have identified numerous pathogenic variants, the aetiology of HA in certain patients remains unclear. Furthermore, female patients with severe HA are rare.

AIM

To investigate the molecular defects underlying severe HA in two patients and provide personalised reproductive interventions for their families.

METHODS

Two patients diagnosed with severe HA without other clinical phenotypes were enrolled in the study. A combination of whole-exome sequencing, real-time quantitative polymerase chain reaction and long-read sequencing (LR-sequencing) was performed to reveal the molecular defects of them, followed by the application of different reproductive intervention strategies.

RESULTS

Proband 1, a 29-year-old man with FVIII activity of 0.8%, did not exhibit common F8 variants, including Inv1 or Inv22, in the coding region. However, he carried a rare maternal novel inversion on ChrX:154148973_154170321, spanning approximately 21.345 Kbp, with breakpoints in introns 13 and 14 of F8. Finally, the couple of Proband 1 opted for assisted reproductive technology using preimplantation genetic testing and successfully conceived. Proband 2, a 20-year-old female with severe HA and FVIII activity of 0.6%, carried inv22 of F8. Further investigation combining whole exome sequencing (WES) and pedigree analysis revealed that she carried a maternal cross-deletion encompassing exons 1-22 of F8, FUNDC2, BRCC3 and CLIC2, along with a de novo missense variant c.5852T>C (p.Leu1951Ser) on her paternal X-chromosome. Chromosome X-inactivation (XCI) analysis demonstrated a highly skewed inactivation of the maternal X chromosome, with a ratio of 98:2. Subsequently, prenatal diagnosis confirmed that the third child in this family did not carry any of the F8 variants present in Proband 2.

CONCLUSION

Our findings provide novel insights into the genetic aetiology of HA and emphasise the importance of a definitive diagnosis in guiding genetic counselling and personalised reproductive interventions for affected individuals and their families.

Evaluation of Safety and Efficacy of Emicizumab Prophylaxis in Egyptian Pediatric Patients with Hemophilia A

Objective

Hemophilia A (HA) is a hereditary X-linked bleeding disorder secondary to deficiency of the clotting factor VIII (FVIII). Emicizumab is a monoclonal antibody that replaces the function of the activated FVIII and prevents bleeding in HA patients. Emicizumab is expected to ameliorate bleeding risk in those patients together with subsequent complications. However, there is a scarcity of data about its safety and efficacy in patients with HA. We aimed to evaluate the safety and efficacy of emicizumab prophylaxis in Egyptian pediatric patients with HA.

Materials and Methods

A prospective cohort study was carried out with 88 HA patients who received emicizumab prophylaxis. Breakthrough bleeding episodes and the annualized bleeding rate (ABR) were reported for all patients before and after emicizumab prophylaxis. Also, all adverse events during prophylaxis were documented to evaluate the safety of emicizumab.

Results

Joint bleeds occurred in 94% of the patients. Among those patients, 58% had one target joint, 36.4% had more than one target joint, and 5.6% had no target joints. Furthermore, 17% of patients were positive for FVIII inhibitors. The median annualized joint bleeding rate was reduced remarkably after emicizumab prophylaxis (36 before versus 0 after emicizumab). The median ABR was 48 before emicizumab versus 0 after emicizumab. Eight patients experienced mild breakthrough bleeding episodes. The most common adverse events were local reactions at injection sites, headache, arthralgia, fever, and diarrhea.

Conclusion

Prophylaxis using emicizumab was associated with a significantly lower bleeding rate in HA patients with and without inhibitors. The majority of patients had zero bleeds with emicizumab prophylaxis.

Patient Experience With Efanesoctocog Alfa for Severe Hemophilia A: Results From the XTEND-1 Phase 3 Clinical Study Exit Interviews

PURPOSE

Hemophilia A is a rare bleeding disorder that leads to recurrent hemarthrosis, which can ultimately result in reduced mobility and poor quality of life. Qualitative exit interviews provide insights into patient perspectives and support the interpretation of quantitative trial data, such as patient-reported outcome measures. In the Phase 3 XTEND-1 study (NCT04161495) of efanesoctocog alfa in participants with severe hemophilia A, exit interviews were conducted to understand pre- and post-study experiences with pain and physical functioning and to evaluate participants' treatment experiences.

METHODS

In XTEND-1, participants (≥12 years old) received once-weekly efanesoctocog alfa prophylaxis 50 IU/kg for 52 weeks (Arm A) or on-demand efanesoctocog alfa 50 IU/kg for 26 weeks followed by 26 weeks once-weekly prophylaxis (50 IU/kg; Arm B). Optional qualitative exit interviews were conducted using a semi-structured guide in a subset of participants following study completion. Interviews included open-ended questions about participants' pre- and post-study experiences with hemophilia A and targeted questions relating to improvements in patient-reported outcomes assessed during XTEND-1, including the Haemophilia Quality of Life Questionnaire for Adults Physical Health subscale (Haem-A-QoL PH). Content validity of the Patient-Reported Outcomes Measurement Information System (PROMIS) Pain Intensity 3a measure was also assessed, particularly the worst pain item.

FINDINGS

Exit interviews were conducted with 29 of 159 patients enrolled in XTEND-1 (mean [range] age 40 [16-73] years). Of 17 participants enrolled in Arm A, 13 (76.5%) reported a "wearing off" feeling with pre-study treatment, including more aches/pain, breakthrough bleeds, and limited physical activities. Joint pain was the most reported pre-study symptom (96.6%; n = 28/29), followed by a reduced ability to move without pain (89.7%, n = 26/29). Improvements following efanesoctocog alfa prophylaxis in ≥1 Haem-A-QoL PH domain were reported by 89.7% (n = 26/29) of participants, with improvements in joint pain, the ability to move without pain, and painful swellings reported by at least 21 (84%) participants. Participants reported that the PROMIS Pain Intensity 3a items were relevant, clear, and easy to answer. Most participants (96.6%) were "quite satisfied" or "very satisfied" with efanesoctocog alfa prophylaxis. All participants preferred efanesoctocog alfa over pre-study treatment.

IMPLICATIONS

The exit interviews demonstrated that once-weekly efanesoctocog alfa prophylaxis resulted in patient-relevant and meaningful improvements in pain and physical functioning, consistent with the quantitative findings from XTEND-1. These results support the validity of the Haem-A-QoL PH and PROMIS Pain Intensity 3a assessed during XTEND-1, demonstrating the potential for change with efficacious treatment.

TRIAL REGISTRY

ClinicalTrials.gov TRIAL REGISTRATION NUMBER: NCT04161495 REGISTRY URL: https://clinicaltrials.gov/study/NCT04161495.

Cost-effectiveness Analysis of Prophylaxis Versus On-demand Treatment for Children With Moderate or Severe Hemophilia A in China

BACKGROUND

It is still being determined if prophylaxis (PR) has superior cost effectiveness compared with on-demand (OD) treatment for moderate or severe hemophilia A (HA) children in China.

OBJECTIVE/PURPOSE

To evaluate the cost-effectiveness of PR and OD treatment for children with moderate or severe HA without inhibitors in China.

METHODS

A retrospective cost-effectiveness study was conducted on 640 HA children (373 and 267 children were on the PR and OD treatment, respectively) from January 2021 to November 2022. The Markov model was used to estimate the economic and clinical outcomes and would run for 17 yearly cycles with the initial age at 2 years. The transfer probabilities were extracted from the data of "Hemophilia Home Care Center" and the literature published. All patients' drug costs were collected from the data of "Hemophilia Home Care Center". One-way and probabilistic sensitivity analyses were conducted on the data to evaluate the robustness of the results.

RESULTS/FINDINGS

PR was consistently associated with higher overall quality-adjusted life years (QALYs) compared with OD treatment (9.59 QALYs vs. 6.85 QALYs). The incremental cost-effectiveness ratio (ICER) of PR compared with the OD treatment was calculated to be approximately US$12,151.35 (RMB¥81,778.55) per QALY gained. This amount was lower than the willingness-to-pay (WTP) threshold of US$38,212.74 (RMB¥257,171.71). One-way sensitivity analysis found that the results were sensitive to the cost of OD and PR treatments.

CONCLUSIONS/IMPLICATIONS

This study indicated that PR is cost-effective compared with OD treatment for children with moderate or severe HA without inhibitors in China.

Clinical validation and application of targeted long-range polymerase chain reaction and long-read sequencing-based analysis for hemophilia: experience from a hemophilia treatment center in China

BACKGROUND

Targeted long-read sequencing (LRS) is expected to comprehensively analyze diverse complex variants in hemophilia A (HA) and hemophilia B (HB) caused by the F8 and F9 genes, respectively. However, its clinical applicability still requires extensive validation.

OBJECTIVES

To evaluate the clinical applicability of targeted LRS-based analysis compared with routine polymerase chain reaction (PCR)-based methods.

METHODS

Gene variants of retrieved subjects were retrospectively and prospectively analyzed. Whole-genome sequencing was performed to further analyze undiagnosed cases. Breakpoints of novel genomic rearrangements were mapped and validated using long-distance PCR and long-range PCR combined with sequencing.

RESULTS

In total, 122 subjects were retrieved. In retrospective analysis of the 90 HA cases, HA-LRS assay showed consistent results in 84 cases compared with routine methods and characterized 6 large deletions with their exact breakpoints confirmed by further validation in 6 cases (routine methods only presented failure in amplifying the involved exons). In prospective analysis of the 21 HA subjects, 20 variants of F8 were identified in 20 cases. For the remaining HA patient, no duplication/deletion or single-nucleotide variant (SNV)/insertion and deletion (InDel) was found, but a potential recombination involving exons 14 and 21 of F8 was observed by LRS. Whole-genome sequencing analysis and further verification defined a 30 478 base pairs (bp) tandem repeat involving exons 14 to 21 of F8. Among the 11 HB patients, HB-LRS analysis detected 11 SNVs/InDels in F9, consistent with routine methods.

CONCLUSION

Targeted LRS-based analysis was efficient and comprehensive in identifying SNVs/InDels and genomic rearrangements of hemophilia genes, especially when we first expanded the panel to include F9. However, further investigation for complex gross rearrangement is still essential.

Utilizing adeno-associated virus as a vector in treating genetic disorders or human cancers

Clinical data from over two decades, involving more than 3000 treated patients, demonstrate that adeno-associated virus (AAV) gene therapy is a safe, effective, and well-tolerated therapeutic method. Clinical trials using AAV-mediated gene delivery to accessible tissues have led to successful treatments for numerous monogenic disorders and advancements in tissue engineering. Although the US Food and Drug Administration (FDA) has approved AAV for clinical use, systemic administration remains a significant challenge. In this review, we delve into AAV biology, focusing on current manufacturing technologies and transgene engineering strategies. We examine the use of AAVs in ongoing clinical trials for ocular, neurological, and hematological disorders, as well as cancers. By discussing recent advancements and current challenges in the field, we aim to provide valuable insights for researchers and clinicians navigating the evolving landscape of AAV-based gene therapy.

Adeno-associated virus therapies: Pioneering solutions for human genetic diseases

Adeno-associated virus (AAV) has emerged as a fundamental component in the gene therapy landscape, widely acknowledged for its effectiveness in therapeutic gene delivery. The success of AAV-based therapies, such as Luxturna and Zolgensma, underscores their potential as a leading vector in gene therapy. This article provides an in-depth review of the development and mechanisms of AAV vector-based therapies, offering a comprehensive analysis of the latest clinical trial outcomes in central nervous system (CNS) diseases, ocular conditions, and hemophilia, where AAV therapies have shown promising results. Additionally, we discusse the selection of administration methods and serotypes tailored to specific diseases. Our objective is to showcase the innovative applications and future potential of AAV-based gene therapy, laying the groundwork for continued clinical advancements.

Acute long-acting anticoagulant rodenticide poisoning in pregnancy: a case report

Introduction

Brodifacoum is a highly potent superwarfarin rodenticide that leads to coagulopathy. Although the effect of warfarin during pregnancy is well understood, reports on superwarfarin poisoning, like brodifacoum, during pregnancy are scarce.

Case Presentation

We report a case involving a woman with a singleton pregnancy who experienced sudden nasal hemorrhage accompanied by hematuria at 34 weeks and 3 days of gestation, with no apparent etiology. It was ultimately diagnosed as acquired coagulopathy resulting from brodifacoum poisoning. Fetal ultrasonography revealed significant intracranial hemorrhage, leading to intrauterine fetal demise and subsequent pregnancy termination. Following the correction of the patient's coagulation profile through intravenous and oral administration of vitamin K1, tailored to the serum levels of brodifacoum, diligent monitoring confirmed that the patient was in stable condition.

Conclusion

The primary hazard associated with the ingestion of brodifacoum is hemorrhage, with clinical presentations varying from asymptomatic cases to overt bleeding, which may present as hematuria, epistaxis, menometrorrhagia, and intracranial hemorrhage. Therefore, the diagnosis and management of this type of poisoning pose significant challenges. Prompt recognition and ongoing care for pregnant individuals affected by rodenticide toxicity are crucial for optimizing maternal health outcomes.

Liver-related aspects of valoctocogene roxaparvovec gene therapy for hemophilia A: expert guidance for clinical practice

ABSTRACT

Adeno-associated virus-based gene therapy (valoctocogene roxaparvovec) is an attractive treatment for hemophilia A. Careful clinical management is required to minimize the risk of hepatotoxicity, including assessment of baseline liver condition to determine treatment eligibility and monitoring liver function after gene therapy. This article describes recommendations (developed by a group of hemophilia experts) on hepatic function monitoring before and after gene therapy. To prevent harmful liver-related effects, gene therapy is contraindicated in patients with uncontrolled liver infections, autoimmune hepatitis, liver stiffness ≥8 kPa, or cirrhosis. Before using gene therapy in patients with liver steatosis or other liver disorders, the risk of liver damage should be considered using a highly individualized approach. Treatment is not recommended in patients with abnormal liver enzymes, including alanine aminotransferase (ALT) at any level above the upper limit of normal (ULN). Therefore, pretreatment assessment of liver health should include laboratory tests, abdominal ultrasound, and liver stiffness measurements by transient elastography (TE). In the first year after therapy, ALT levels should be monitored 1 to 2 times per week to detect elevations ≥1.5× ULN, which may require immunosuppressant therapy. Patients with ALT elevation should receive prednisone 60 mg/d for 2 weeks, followed by stepwise tapering when ALT returns to baseline. ALT monitoring should continue long term (every 3-6 months), along with abdominal ultrasound (every 6 months) and TE (yearly) evaluations. When patients with good liver health are selected for treatment and closely monitored thereafter, ALT elevations can be promptly treated and are expected to resolve without long-term hepatic sequelae.

Economic Burden of Haemophilia from a Societal Perspective: A Scoping Review

INTRODUCTION

Haemophilia is a rare genetic bleeding disorder that leads to musculoskeletal complications. The high cost of haemophilia treatment necessitates a thorough evaluation of its economic burden. However, due to the difficulty of estimating direct non-medical, indirect, and intangible costs, studies often underestimate the actual economic burden of haemophilia. This scoping review aims to summarise economic studies in haemophilia conducted from a societal perspective.

METHODS

A systematic search across eight scholarly databases, grey literature, and reference lists until the 5th of July 2023 was conducted to identify relevant studies. The inclusion criteria encompassed full-text, English-language publications of economic analyses in congenital haemophilia from a societal perspective. Model-based studies and those adopting a payer perspective were excluded. Costs were adjusted to international dollars (I$) and US dollars (US$) in 2022 for comparability.

RESULTS

Out of 2993 potential sources identified, 25 studies met the inclusion criteria, covering 7226 persons with haemophilia across 22 countries. All studies reported direct medical costs, with four excluding the cost of haemostatic therapy. Fifteen studies reported direct formal non-medical costs, while eight reported direct informal non-medical costs. All but one study reported the indirect costs. The average annual costs of haemophilia varied widely based on treatment modality, disease severity, geographical location, and included cost categories. When including the cost of clotting factor replacement therapy (CFRT), the total cost for severe haemophilia without inhibitors ranged from 1566 I$ to 700,070 I$ per person per year (lowest value reported in India and highest in the United States). CFRT represented up to 99.9% of the total cost for those receiving prophylaxis and up to 95.1% for episodic treatment. Haemostatic therapies accounted for 82% of the total cost in patients with inhibitors.

CONCLUSION

There is a significant heterogeneity in defining cost categories required for a comprehensive economic analysis from a societal perspective. While haemostatic therapies constitute a substantial portion of the overall cost, direct non-medical and indirect costs are crucial as they are often paid out-of-pocket and may impede access to treatment. It is essential for haematologists and economists to establish a standardised costing framework for future studies, particularly in the era of novel therapies.

Quantitative MRI assessment of joint effusion using T2-relaxometry at 3 Tesla: a feasibility and reproducibility study

OBJECTIVE

T2-relaxometry could differentiate between physiological and haemorrhagic joint effusion (≥ 5% blood) in vitro. Are quantitative T2-relaxation time measurements of synovial fluid feasible and reproducible in vivo in clinically bleed-free joints of men with haemophilia?

MATERIALS AND METHODS

In this cross-sectional study, we measured T2-relaxation times of synovial fluid in clinically bleed-free ankles, knees or elbows of men with severe haemophilia A using a T2-mapping sequence (duration ≤ 7 min) at 3 Tesla MRI. Manual and circular regions of interest (ROI) were drawn in the synovial fluid of each joint by two independent observers to measure T2-relaxation times. Measurement feasibility was expressed as the success rate of the measurements by both observers. The interobserver and intraobserver reproducibility of the measurements were evaluated by the intraclass correlation coefficient of absolute agreement (ICC) and the limits of agreement (LoA) from Bland Altman analysis.

RESULTS

We evaluated 39 clinically bleed-free joints (11 ankles, 12 knees, 16 elbows) of 39 men (median age, 24 years; range 17-33) with severe haemophilia A. The success rate of the T2-measurements was ≥ 90%. Interobserver reliability was good to excellent (manual ROI: ICC = 0.92, 95% CI 0.76-0.97; circular ROI: ICC = 0.82, 95% CI 0.66-0.91) and interobserver agreement was adequate (manual ROI: LoA = 71 ms; circular ROI: LoA = 146 ms). Intraobserver reliability was good to excellent (manual ROI: ICC = 0.78, 95% CI - 0.06-0.94; circular RO: ICC = 0.99, 95% CI 0.98-0.99) and intraobserver agreement was good (manual ROI: LoA = 63 ms; circular ROI: LoA = 41 ms).

CONCLUSION

T2-relaxometry of synovial fluid in haemophilia patients is feasible with good interobserver and intraobserver reproducibility.

Real-world insights into the management of hemophilia A in Italy: treatment patterns and healthcare resource utilization

PURPOSE

This real-world analysis described the Hemophilia A (HA) population in Italy, evaluating drug utilization and consumption of factor VIII (FVIII) products of patients under prophylaxis and on-demand therapy.

METHODS

From Jan-2017 to Jun-2022, male patients with HA were identified through prescriptions of FVIII products [extended half-life FVIII, standard half-life recombinant FVIII, and plasma-derived FVIII (EHL FVIII, SHL rFVIII, and pdFVIII, respectively)], or emicizumab or FVIII plus von Willebrand factor or HA-related hospitalization using administrative flows of Italian healthcare entities. Patients on treatment with FVIII products during 2021-2022 were stratified by treatment regimen (prophylaxis/on-demand). The mean annual consumption expressed in International Units (IU) of EHL FVIII and SHL FVIII in patients treated during 2021-2022 having at least 12-month follow-up were assessed.

RESULTS

Among included HA patients, 145 (39.5%) received EHL FVIII and 222 (60.5%) SHL FVIII. Of 165 patients on prophylaxis, 105 (64%) received an EHL FVIII and 60 (36%) an SHL FVIII. The mean annual consumption of FVIII was 336,700 IU (median 319,000 IU) for EHL FVIII and 440,267 IU (median 360,500 IU) for SHL FVIII. Specifically, for patients on EHL FVIII, the most common drugs were efmoroctocog alfa (N = 51) and damoctocog alfa pegol (N = 50), followed by turoctocog alfa pegol (N = 25) and rurioctocog alfa pegol (N = 19). Of 702 HA patients initially treated with FVIII products, 74 (10.5%) switched to emicizumab during follow-up.

CONCLUSION

These findings revealed an extensive use of EHL FVIII products, suggesting growing efforts from clinicians to optimize prophylactic strategies and achieve better bleeding protection.

Exercise-based telerehabilitation for the management of chronic pain in people with severe haemophilia: a mixed-methods feasibility study

BACKGROUND

Chronic pain is reported by between 30 and 71% of people with haemophilia (PWH). Exercise is shown to be effective for pain management in other arthritides, but it remains unclear if such an approach is effective or acceptable to PWH. The aim of this study was to evaluate the feasibility and acceptability of a telerehabilitation exercise intervention for PWH living with chronic pain.

METHODS

This was a multisite, non-randomised, pre-post feasibility design, with a nested qualitative study. People with severe haemophilia > 18 years, living with chronic pain, were recruited. The intervention comprised 12 low-impact/moderate intensity, individualised exercise sessions and 3 knowledge-sharing and discussion sessions. Primary objectives assessed according to predefined progression criteria were as follows: (a) recruitment rate (5 participants enrolled per site over 8 weeks), (b) adherence (≥ 75% participants would adhere to ≥ 75% of sessions), (c) follow-up rate (≥ 75% completion of self-reported measures), (d) fidelity (intervention delivered as described in protocol) and (e) safety (≤ 30% participants would report adverse events). Acceptability was evaluated from thematic analysis of post-intervention participant interviews. Preliminary evaluation of self-reported pain, function and quality of life (QoL) was a secondary objective. Results were reported using descriptive statistics integrated with qualitative findings.

RESULTS

Ten PWH were recruited and completed the intervention. Nine agreed to be interviewed post intervention. Attendance at individual sessions was 84.5% compared to 52.1% for the group sessions. Outcome measures were successfully completed for 100% at baseline, 70% at intervention end and 60% at 3-month follow-up. No serious adverse events were recorded. Group median values in outcome measures (pain, function, QoL) showed minimal change post intervention. Participant interviews highlighted high levels of enjoyment, confidence in continuing exercises independently and positive views of virtual delivery and condition-specific exercise.

CONCLUSIONS

Recruitment rate and safety met the predefined progression criteria. Fidelity partially met the progression criteria, but the follow-up rate for self-reported measures did not. The study was acceptable to both participants and physiotherapists. Further intervention development is needed to review approaches to outcome measure collection and refine the usefulness of the knowledge-sharing sessions.

TRIAL REGISTRATION

The study was prospectively registered on 9 July 2021: International Standard Randomised Controlled Trial Number ISRCTN 17454597.

Management of Bleeding Diathesis in Elective and Orthopaedic Trauma: A Review

There is a general need among orthopaedic surgeons for practical advice on managing patients with bleeding disorders. Appropriate diagnosis and management of these disorders is paramount once discovered before, during, or after the patient's surgical course. Bleeding disorders disrupt the body's ability to control bleeding, commonly through platelet function and blood clotting. Normally, the vessel contracts and retracts once disruption of blood vessels occurs, limiting blood loss. Blood platelets adhere to exposed collagen, aggregate at the site, and obstruct blood loss. Because platelet aggregates are temporary, blood clotting is needed to back up the platelet plug and provide a milieu for the healing process that completes the hemostatic events. Disorders that interfere with any of these events can result in hemorrhage, drainage, or rebleeding. Bleeding disorders are a group of conditions, either hereditary or acquired, marked by abnormal or excessive bleeding and/or bruising. The most effective methods for assessing coagulation disorders include a detailed history and a series of blood tests. Clinical examination findings are notable but may be less specific. If a surgical patient has a bleeding disorder discovered preoperatively, postoperatively, or intraoperatively, treatments exist with medications, surgical management, interventional radiology procedures, and replacement therapy.

Anti-mCD20 in combination with α-mCXCL13 monoclonal antibody inhibits anti-FVIII antibody development in hemophilia A mice

Anti-factor VIII (FVIII) antibody development poses a significant challenge in hemophilia A (HA) patients receiving FVIII protein replacement therapy. There is an urgent need for novel therapeutic strategies to inhibit the production of anti-FVIII inhibitory antibodies (inhibitors) in HA. This study aimed to investigate a combination monoclonal antibody (mAb) therapy targeting CXCL13 and CD20 on the development of anti-FVIII antibodies in a HA murine model, along with the underlying mechanisms involved. Specifically, mAbs targeting mouse CD20 (18B12) with an IgG2a backbone and mouse CXCL13 (2C4) with an IgG1 backbone were synthesized. HA mice with FVIII inhibitors were established, and the results revealed that the combination therapy of anti-mCD20 with α-mCXCL13 significantly suppressed anti-FVIII antibody development and induced FVIII tolerance. Furthermore, this combination therapy led to a marked reduction of peripheral and splenic follicular helper T cells and an enhancement of regulatory T cell induction, along with sustained depletion of bone marrow and splenic plasma cells in HA mice with preexisting FVIII immunity. Thus, the concurrence of blockage of CD20 and neutralization of CXCL13 hold promise as a therapeutic strategy for HA patients with inhibitors.

Laboratory Evaluation of Interferences Associated with Factor XIa Inhibitors Asundexian and Milvexian in Routine Coagulation Assays

Direct oral anticoagulants (DOACs) are increasingly used for the treatment of thrombosis. While inhibitors of factor IIa and factor Xa have shown effectiveness, the risk of bleeding remains a significant concern. Recently, direct factor XIa inhibitors-including asundexian and milvexian-have emerged as potential anticoagulation therapies, based on clinical observations that patients with factor XIa deficiencies seldom present with spontaneous bleeding tendencies. The interferences associated with DOACs in routine and specialised coagulation assays are well-described; however, the interferences associated with emerging FXIa inhibitors are largely uncharacterised. Here, we briefly report the impact of asundexian and milvexian in routine coagulation assays using in vitro plasma-based systems. Asundexian and milvexian induce concentration-dependent prolongations in APTT-based assays with curvilinear regressions, which may be suitable for the measurement of pharmacodynamic effects at peak levels ex vivo. We also report differential sensitivities of APTT-based assays-particularly at higher FXIa inhibitor concentrations-highlighting the clinical need for an extensive evaluation of interferences associated with FXIa inhibitors in coagulation assays.

MR Imaging of Hemosiderin Deposition in the Ankle Joints of Patients with Haemophilia: The Contribution of a Multi-Echo Gradient-Echo Sequence-Correlation with Osteochondral Changes and the Number and Chronicity of Joint Bleeds

We aim (a) to introduce an easy-to-perform multi-echo gradient-echo sequence (mGRE) for the detection of hemosiderin deposition in the ankle joints of boys with haemophilia (b) to explore the associations between the presence and severity of hemosiderin deposition and the other components of haemophilic arthropathy, the clinical score, and the number and chronicity of joint bleeds. An MRI of 41 ankle joints of 21 haemophilic boys was performed on a 3 T MRI system using an mGRE sequence in addition to the conventional protocol. Conventional MRI and mGRE were separately and independently assessed by three readers, namely, two musculoskeletal radiologists and a general radiologist for joint hemosiderin. We set as a reference the consensus reading of the two musculoskeletal radiologists, who also evaluated the presence of synovial thickening, effusion, and osteochondral changes. Excellent inter-reader agreement was obtained using the mGRE sequence compared to the conventional protocol (ICC: 0.95-0.97 versus 0.48-0.89), with superior sensitivity (90-95% versus 50-85%), specificity (95.2-100% versus 76.2-95.2%), and positive (95-100% versus 71-94.4%) and negative predictive value (91.3-95.5% versus 87-63%). Hemosiderin deposition was associated with osteochondral changes, synovial thickening, clinical score, and the total number of ankle bleeds, while it was inversely related with the time elapsed between the last joint bleed and MRI. (p < 0.05). The application of an mGRE sequence significantly improved hemosiderin detection, even when performed by the less experienced reader. Joint hemosiderin deposition was associated with the other components of haemophilic arthropathy and was mostly apparent in recent joint bleeds.

The Role of Clot Waveform Analysis and Related Parameters in the Diagnosis and Treatment of Hemophilia A

BACKGROUND

 Hemophilia A (HA) is an inherited bleeding disorder caused by a deficiency or defect in factor VIII (FVIII).

METHODS

 We investigated the role of clot waveform analysis (CWA) of activated partial thromboplastin time in the diagnosis and therapeutic monitoring of HA. The changes in CWA parameters the maximum clotting velocity (|Min1|), maximum clotting acceleration (|Min2|), and maximum clotting deceleration (|Max2|) were detected among mild, moderate, and severe HA groups.

RESULTS

 As the severity of HA subtypes increased, the levels of |Min1|, |Min2|, and |Max2| progressively decreased (p < 0.05). Receiver operating characteristic curve analysis showed that |Max2| and |Min2| were more effective than |Min1| in distinguishing different types of HA patients, with higher diagnostic efficacy. The standard curves based on Actin FSL reagent for normal and low levels of FVIII:C-|Max2| were established, with R2 values of 0.98 and 0.99, respectively. These curves can be utilized for monitoring during replacement therapies involving full-length recombinant FVIII and B-domain-deleted FVIII. Thirty cases of HA patients utilized the FVIII-|Max2| standard curve to obtain individual pharmacokinetics characteristic parameters. The clearance, half-life (t1/2), time to FVIII:C of 1% above baseline (tt1%), and predicted dosage showed no statistically significant differences compared with one-stage assay (p > 0.05).

CONCLUSION

 CWA is an economical and practical tool, and its related parameters are associated with the severity of HA. It has promising clinical prospects in predicting FVIII:C levels and individualized treatment when HA patients undergo replacement therapy.

Proteomic exploration of potential blood biomarkers in haemophilic arthropathy

Background and Aims

The pathophysiology of haemophilic arthropathy (HA) is complex and largely undefined. Proteomic analyses provide insights into the intricate mechanisms of the HA.Our study aimed to identify differentially expressed proteins in relation to the severity of HA, explore their pathophysiological roles, and evaluate their potential as HA biomarkers.

Methods

Our cross-sectional observational study encompassed 30 HA patients and 15 healthy subjects. Plasma samples were pooled into three groups of 15 samples from those with severe haemophilic arthropathy (sHA), mild haemophilic arthropathy (mHA) and healthy controls. Proteomic analysis was performed using liquid chromatography-mass spectrometry. The severity of HA was assessed using the World Federation of Haemophilia Physical Examination Score and ultrasonography following the Haemophilia Early Arthropathy Detection with Ultrasound (HEAD-US) guidelines.

Results

A total of 788 proteins were identified, with 97% of the uniquely identified proteins being expressed in all analysed groups. We identified several up and downregulated proteins across the groups that were mainly related to inflammatory and immunity-modulating processes, as well as joint degeneration. We highlighted ten proteins relevant for the development of HA: cathepsin G, endoplasmic reticulum aminopeptidase 2, S100-A9, insulin-like growth factor I, apolipoprotein (a), osteopontin, pregnancy zone protein, cartilage oligomeric matrix protein, CD44, and cadherin-related family member 2.

Conclusion

Our analysis identified several proteins that shed further light on the distinctive pathogenesis of HA and could serve for biomarker research. However, these results need to be validated on a larger patient group.

[How to interpret and pursue a prolonged quick time or APTT]

The standard hemostasis workup [quick time (QT), and activated partial thrombin time (APTT)] is very commonly prescribed but its interpretation is often difficult for practitioners who are not specialized in hemostasis. Here, we review the principles of the diagnostic approach to these tests. Only a very basic knowledge of the coagulation cascade is necessary to identify which clotting factor tests to prescribe and to interpret the results. Deficiency in several clotting factors suggests liver dysfunction, disseminated intravascular coagulation (DIC) or vitamin K deficiency. If a single factor is deficient, we review the different causes of acquired deficiencies and briefly discuss the characteristics of the different congenital defects, which generally require specialized management. Lupus anticoagulant is a common and generally benign cause of prolonged APTT to be aware of, which is not related to a hemorrhagic risk. A good knowledge of the diagnostic approach to abnormal QT or APTT generally allows the resolution of the most common situations.

Bioclinical features of haemophilia patients in Benin in 2023: Towards better care

OBJECTIVE

To analyse the demographic, clinical and laboratory data of Beninese patients with haemophilia.

METHOD

A prospective survey was conducted in three different hospitals of Benin from April 2021 to March 2022, to analyse clinical and biological features of patients with haemophilia previously diagnosed or identified based on personal/family history.

RESULTS

A total of 101 patients were studied, 97 with haemophilia A and 4 with haemophilia B, including 26 new cases identified after family investigation. Their median age was 11 years, and the most frequent initial manifestations were cutaneous-mucosal haemorrhages (29.70%) and post-circumcision haemorrhages (25.74%). Previous joint bleedings were present in 77% of them, with an arthropathy in 65 cases, which particularly affected the knees (75%), elbows (41%) and ankles (29%). Factor VIII (FVIII) levels combined with activated partial thromboplastin time (APTT) values did not always enable, as would be expected, the distinction between severe and moderate haemophilia, since they were >1 IU/dl in 31 of 74 patients with APTT > 80 s, and between 1 and 2 IU/dl in 26 other cases with previous joint haemorrhages, including 18 with chronic arthropathy. Therefore, for these patients, severe haemophilia could not be excluded, and this uncertainty probably reflects technical difficulties affecting the pre-analytical and analytical stages of the APTT and FVIII/IX assays.

CONCLUSION

Our study proved that haemophilia is a significant reality in Benin, but also remains under-diagnosed in some districts of the country. In addition, more reliable biological tests are needed in the future to better define the severity of the disease and improve treatment of patients.

Moving towards Normalization of haemostasis and health equity: Evolving treatment goals for haemophilia A

BACKGROUND

Treatment options for people with haemophilia are evolving at a rapid pace and a range of prophylactic treatment options using various technologies are currently available, each with their own distinct safety and efficacy profile.

TREATMENT GOALS

The access to replacement therapy and prophylaxis has driven a dramatic reduction in mortality and resultant increase in life expectancy. Beyond this, the abolition of bleeds and preservation of joint health represent the expected, but rarely attained, goals of haemophilia treatment and care. These outcomes also do not address the complexity of health-related quality of life impacted by haemophilia and its treatment.

CONCLUSION

Capitalizing on the major potential of therapeutic innovations, 'Normalization' of haemostasis, as a concept, should include the aspiration of enabling individuals to live as normal a life as possible, free from haemophilia-imposed limitations. To achieve this-being supported by the data reviewed in this manuscript-the concept of haemostatic and life Normalization needs to be explored and debated within the wider multidisciplinary teams and haemophilia community.

Stability, Balance, and Physical Variables in Patients with Bilateral Hemophilic Arthropathy of the Ankle versus Their Healthy Peers: A Case-Control Study

(1) Background: The recurrence of hemarthrosis in patients with hemophilia triggers a pathophysiological process of degenerative, progressive, and irreversible joint destruction. This hemophilic arthropathy is characterized by chronic pain, muscle atrophy, loss of mobility, and proprioceptive alterations. As the same joint undergoes repeated hemarthrosis, the function of the mechanical receptors deteriorates, causing a pathophysiological modulation and deterioration of the musculoskeletal system. The objective was to analyze the differences in stability and balance, as well as in ankle dorsal flexion, functionality, and muscle strength, between patients with bilateral hemophilic arthropathy and their healthy peers. (2) Methods: A cross-sectional descriptive case-control study was performed. Twenty-two participants were recruited: 10 adult patients with bilateral hemophilic arthropathy of the knee and ankle and 12 healthy subjects. The variables were balance (Rs Scan pressure platform), ankle dorsiflexion range of motion (Leg Motion), functionality (2-Minute Walk Test), and ankle dorsal strength (dynamometry). (3) Results: Statistically significant differences (p < 0.05) were found in the balance without visual support in the Max-Y variable (MD = 2.83; CI95%: 0.33;5.33; Effect size (d) = 0.67), ankle dorsiflexion (MD = 16.00; CI95%: 14.30; 20.0; d = 7.46), and strength of the ankle flexor muscles (MD = 128.50; CI95%: 92.50; 153.60; d = 2.76). (4) Conclusions: Ankle range of motion in dorsal flexion, functionality, and muscle strength in dorsal flexion is poorer in patients with bilateral lower limb hemophilic arthropathy than in their healthy peers. Patients with bilateral hemophilic ankle arthropathy have statistically poorer stability and balance without visual support than their healthy peers.

Detection of hemophilia A genetic variants using third-generation long-read sequencing

BACKGROUND

Hemophilia A (HA) is an X-linked recessive genetic disorder caused by pathogenic variations of the factor VIII -encoding gene, F8 gene. Due to the large size and diverse types of variations in the F8 gene, causative mutations in F8 cannot be simultaneously detected in one step by traditional molecular analysis, and genetic molecular diagnosis and prenatal screening of HA still face significant difficulties and challenges in clinical practice. Therefore, we aimed to develop and validate an efficient, accurate, and time-saving method for the genetic detection of HA.

METHODS

A comprehensive analysis of hemophilia A (CAHEA) method based on long-range PCR and long-read sequencing (LRS) was used to detect F8 gene mutations in 14 clinical HA samples. The LRS results were compared with those of the conventional methods to evaluate the accuracy and sensitivity of the proposed approach.

RESULTS

The CAHEA method successfully identified 14 F8 variants in all probands, including 3 small insertion deletions, 4 single nucleotide variants, and 7 intron 22 inversions in a "one-step" manner, of which 2 small deletions have not been reported previously. Moreover, this method provided an opportunity to analyze the mechanism of rearrangement and the pathogenicity of F8 variants. The LRS results were validated and found to be in 100% agreement with those obtained using the conventional method.

CONCLUSION

Our proposed LRS-based F8 gene detection method is an accurate and reproducible genetic screening and diagnostic method with significant clinical value. It provides efficient, comprehensive, and accurate genetic screening and diagnostic services for individuals at high risk of HA as well as for premarital and prenatal populations.

Cellular and molecular mechanisms of skin wound healing

Wound healing is a complex process that involves the coordinated actions of many different tissues and cell lineages. It requires tight orchestration of cell migration, proliferation, matrix deposition and remodelling, alongside inflammation and angiogenesis. Whereas small skin wounds heal in days, larger injuries resulting from trauma, acute illness or major surgery can take several weeks to heal, generally leaving behind a fibrotic scar that can impact tissue function. Development of therapeutics to prevent scarring and successfully repair chronic wounds requires a fuller knowledge of the cellular and molecular mechanisms driving wound healing. In this Review, we discuss the current understanding of the different phases of wound healing, from clot formation through re-epithelialization, angiogenesis and subsequent scar deposition. We highlight the contribution of different cell types to skin repair, with emphasis on how both innate and adaptive immune cells in the wound inflammatory response influence classically studied wound cell lineages, including keratinocytes, fibroblasts and endothelial cells, but also some of the less-studied cell lineages such as adipocytes, melanocytes and cutaneous nerves. Finally, we discuss newer approaches and research directions that have the potential to further our understanding of the mechanisms underpinning tissue repair.

Infrared thermography: An investigative tool for detection of subclinical bleed in hemophilia on prophylaxis

Background & objectives Subclinical joint bleed is a matter of concern in individuals with hemophilia on prophylaxis. Ultrasonography (USG) is mostly used for the screening of subclinical bleeds in such individuals but it has its own limitations. Thus a more comprehensive technology is required for the detection of the same. This study undertook to evaluate the efficacy of infrared thermography (IRT) for detection of subclinical joint bleeds and its comparison with ultrasonography and MRI (Magnetic Resonance Imaging), considering MRI as the gold standard. Methods Forty eight asymptomatic individuals with hemophiliacs on prophylaxis and 15 healthy males as controls were recruited. IRT, USG and MRI were done in all participants included in the study. FLIR camera systems were used for the capture of thermograms of the joints in both the study groups. Results The mean of maximum temperature difference>0.5K (ΔT max >0.5K) as compared to a healthy joint was considered as significant. Subclinical bleeds were detected in 23.9, 7.29 and 27.08 per cent participants by IRT, USG and MRI respectively. Sensitivity and specificity of IRT and USG was detected to be 88.4 and 97.67 per cent, and 26.9 and 99 per cent, respectively. Interpretation & conclusions The findings of this study suggest that IRT is an effective tool for detection of subclinical joint bleeds in individuals with hemophilia and can be used for the monitoring of the joints in such individuals.

Comparative analysis of thrombin generation platforms for patients with coagulation factor deficiencies: A comprehensive assessment

INTRODUCTION

Thrombin generation assays (TGAs) assess the overall functionality of the hemostatic system and thereby provide a reflection of the hemostatic capacity of patients with disorders in this system. Currently, four (semi-)automated TGA platforms are available: the Calibrated Automated Thrombogram, Nijmegen Hemostasis Assay, ST Genesia and Ceveron s100. In this study, we compared their performance for detecting patients with congenital single coagulation factor deficiencies.

MATERIALS AND METHODS

Pooled patient samples, healthy control samples and normal pooled plasma were tested on all four platforms, using the available reagents that vary in tissue factor and phospholipid concentrations. The TGA parameters selected for analysis were peak height and thrombin potential. Results were normalized by using the calculated mean of healthy controls and a correction for between-run variation. Outcomes were presented as relative values, with the mean of healthy controls standardized to 100 %.

RESULTS

Across all platforms and reagents used, thrombin potentials and peak heights of samples with coagulation factor deficiencies were lower than those of healthy controls. Reagents designed for bleeding tendencies yielded the lowest values on all platforms (relative median peak height 19-32 %, relative median thrombin potential 19-45 %). Samples representing more severe coagulation factor deficiencies generally exhibited lower relative peak heights and thrombin potentials.

CONCLUSIONS

Thrombin generation assays prove effective in differentiating single coagulation factor deficient samples from healthy controls, with modest discrepancies observed between the platforms. Reagents designed for assessing bleeding tendencies, featuring the lowest tissue factor and phospholipid concentrations, emerged as the most suitable option for detecting coagulation factor deficiencies.

Reduced doses of emicizumab achieve good efficacy: Results from a national-wide multicentre real-world study in China

INTRODUCTION

Reduced doses of emicizumab improve the affordability among patients in developing countries. However, the relationship between variant dose selection and efficacy in the real world of China is still unclear.

AIM

This study aimed to investigate the efficacy and safety of emicizumab especially in those on reduced dose regimens in a real-world setting.

METHODS

We carried out a multicentre study from 28 hospitals between June 2019 and June 2023 in China and retrospectively analysed the characteristics including demographics, diagnosis, treatment, bleeding episodes, and surgical procedures.

RESULTS

In total, 127 patients with haemophilia A, including 42 with inhibitors, were followed for a median duration of 16.0 (IQR: 9.0-30.0) months. Median age at emicizumab initiation was 2.0 (IQR: 1.0-4.0) years. Median (IQR) consumption for loading and maintenance was 12.0 (8.0-12.0) and 4.2 (3.0-6.0) mg/kg/4 weeks, respectively. While on emicizumab, 67 (52.8%) patients had no bleeds, whereas 60 (47.2%) patients had any bleeds, including 26 with treated bleeds. Compared to previous treatments, patients on emicizumab had significantly decreased annualized bleeding rate, annualized joint bleeding rate, target joints and intracerebral haemorrhage. Different dosages had similar efficacy except the proportion of patients with treated spontaneous bleeds and target joints. Adverse events were reported in 12 (9.4%) patients. Postoperative excessive bleeding occurred following two of nine procedures.

CONCLUSION

This is the largest study describing patients with HA receiving emicizumab prophylaxis on variant dose regimens in China. We confirmed that nonstandard dose is efficacious and can be considered where full-dose emicizumab is ill affordable.

Clinical Efficacy of Intra-articular Tranexamic Acid Injection in the Management of Hemophilia with Total Hip Arthroplasty: A 24-month Retrospective Cohort Study

OBJECTIVE

Total hip arthroplasty (THA) effectively treats end-stage hemophilic hip arthropathy. Given hemophilia's unique characteristics, perioperative bleeding remains a significant risk for patients undergoing THA. Tranexamic acid (TXA), an efficient antifibrinolytic agent, may benefit the outcomes of THA for patients with hemophilia (PWH). This study aims to explore the clinical efficacy of intra-articular injection of TXA in treating perioperative bleeding in PWH and assess its additional clinical benefits.

METHODS

The retrospective study comprised data of PWH who received THA from January 2015 to December 2021 in the research center. A total of 59 individuals were included in the study, divided into a TXA group (n = 31) and a non-TXA group (n = 28). We compared various parameters, including total blood loss (TBL), visible blood loss (VBL), occult blood loss (OBL), intraoperative coagulation factor VIII (FVIII) consumption, perioperative total FVIII consumption, hemoglobin (HB), erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), length of hospital stay, hospitalization costs, length of surgery, total protein, activated partial thromboplastin time (APTT), D-dimer, rate of joint swelling, hip joint range of motion (ROM), visual analogue scale (VAS), and Harris hip joint function scale (HHS) between the two groups. Follow-up assessments were conducted for up to 24 months. A Student's t test was utilized for the statistical analysis.

RESULTS

This study demonstrated that intra-articular TXA effectively reduced TBL (1248.19 ± 439.88 mL, p < 0.001), VBL (490.32 ± 344.34 mL, p = 0.003), and OBL (757.87 ± 381.48 mL, p = 0.004) in PWH who underwent THA. TXA demonstrated effectiveness in reducing VAS scores on POD1, POD7, and POD14 and joint swelling rates on POD1, POD7, POD14, and at discharge (p < 0.05). Additionally, the TXA group achieved higher HHS ratings at all follow-up time points (p < 0.05), showing superior hip joint mobility, lower postoperative inflammation levels, reduced factor VIII consumption during surgery, and less postoperative nutritional loss. No statistically significant differences were observed between the two groups in terms of hospital stay, hospitalization costs, surgery duration, and coagulation indicators.

CONCLUSION

Intra-articular injection of TXA reduces perioperative bleeding in PWH undergoing THA while also improving joint mobility, post-operative rehabilitation, and quality of life. This may provide value for the future application of TXA in PWH.

Effects of resistance training on muscle strength in adults with haemophilia: A systematic review and meta-analysis

INTRODUCTION

Although resistance training is frequently prescribed for people with haemophilia (PWH), no previous meta-analyses have quantified the effect of this intervention on muscle strength, nor the implications of the intervention's modality and duration.

AIM

(1) To determine the effects of resistance training on muscle strength in adults with haemophilia; (2) To determine the most effective duration and modality among the exercise protocols.

METHODS

A systematic search from inception until 28 November 2023 was conducted in PubMed, Embase, Web of Science, CENTRAL and CINAHL databases. We included randomised controlled trials or before-after studies that involved resistance training without other physiotherapy co-interventions. Study selection, data extraction and risk of bias assessment were independently performed by two reviewers. Disagreements were resolved in consultation with a third author. The level of evidence was determined according to the GRADE methodology.

RESULTS

Seven studies were included. Measurements of knee extensor strength and elbow extensor strength were included in the meta-analysis. Subgroup analysis showed significant effects for both elastic resistance protocols (SMD: 0.54; 95% CI: 0.02-1.07) and conventional training (isometric and weight-based equipment) (SMD: 0.88; 95% CI: 0.50-1.25), demonstrating small and moderate effect sizes respectively. Additionally, both protocols of duration 5-7 weeks (SMD: 1.16, 95% CI: 0.63-1.69) as well as those of duration ≥8 weeks (SMD: 0.57, 95% CI: 0.20-0.94) showed a significant difference.

CONCLUSION

Resistance training is effective in improving muscle strength of the knee and elbow extensors in PWH. Both elastic resistance and conventional training show benefits.

Outcome measures in hemophilia: current and future perspectives

INTRODUCTION

Hemophilia can detrimentally affect patients' quality of life and likelihood of survival. In the evolving landscape of therapies, the therapeutic gain of each treatment must be understood to accurately position it in the therapeutic armamentarium. Accordingly, appropriate outcomes must be measured with appropriate tools.

AREAS COVERED

Our narrative review (PubMed search for 'hemophilia AND outcome' until June 2023), provides a compendium of outcome measures used in hemophilia clinical research. To define each outcome measure's relative value and applicability, several characteristics are critically discussed.

EXPERT OPINION

Bleeding assessment, first annual/annualized bleeding rate, remains central in evaluating the efficacy and safety of hemophilia treatments. As modern therapies improve clinical outcomes toward zero bleeding events, this endpoint may become less sensitive to detect differences between therapeutic approaches. Technological advancements necessitate the adaptation of outcome measures to address infrequent bleeding events, age-related comorbidities, and laboratory parameters with limited comparability after different treatments. Considerable effort has been dedicated to the development of tools that comprehensively assess coagulation, such as thrombin generation assays. Patient-reported outcome measures are gaining importance although limited by their subjectivity. A definitive set of research outcome measures remains elusive. Outcomes may need to be tailored to different therapeutic interventions.

Accuracy and clinical role of digital templating for total knee arthroplasty performed on haemophilic knees

INTRODUCTION

In total knee arthroplasty (TKA), choosing the correct implant size is important. There is lack of data on accuracy of templating on haemophilic knees. Our aim was to test the accuracy of 2D digital templating for TKA on haemophilic arthropathy (HA) of knee.

MATERIALS AND METHODS

TKAs performed on HA between January 2011 and January 2022 were screened. Osteoarthritis (OA) group was created as control group by a one-to-one matching regarding type of implant used. Intra- and interobserver correlations were measured in HA, then correlation between templated and implanted sizes was investigated in four assessments (femur AP, femur lateral, tibia AP, tibia lateral), then compared with OA group. Fifty-eight knees in each group included.

RESULTS

Regarding intraobserver correlation in HA, there was excellent correlation for femur AP [.93 (.73-.98)], femur lateral [.98 (.91-.99)], and tibia AP (1.0) templating. Regarding interobserver correlation in HA, excellent correlation was observed for femur lateral [.93 (.74-.98)] and tibia AP templating [.90 (.65-.97)]. Regarding correlation of templated and applied sizes in HA; tibia AP, tibia lateral and femur lateral templating showed good correlation [.81 (.70-.89), .86 (.77-.91), .79 (.67-.87) while femur AP templating showed moderate correlation [.67 (.50-.79)]. Comparing HA and OA, there was no difference in correlation levels regarding femur AP, femur lateral, tibia AP and tibia lateral templating (p = .056, p = .781, p = .761, p = .083, respectively).

CONCLUSION

Although 2D digital templating shows comparable correlation in HA and OA, clinical applicability of templating on HA appears to be limited in its current state.

Changes in Quality of Life, Adherence, and Kinesiophobia in Patients with Hemophilia Treated with Extended Half-Life Treatment: Final Results of the LongHest Project

(1) Background: Hemophilia is a bleeding disorder characterized by hemarthrosis. Prophylaxis is the gold standard for bleeding prevention. Extended half-life (EHL) recombinant FVIII replacement products have shown to be associated with low bleeding rates. The aim was to evaluate the efficacy of EHL prophylaxis in improving perceived quality of life, adherence to treatment, and kinesiophobia in patients with hemophilia. (2) Methods: This was a prospective cohort study. Forty-six patients from different regions, who had started EHL FVIII concentrate prophylactic treatment, were evaluated at baseline and at 12-month follow-up. The study variables were as follows: perceived quality of life (36-Item Short Form Health Survey), adherence to treatment (Validated Hemophilia Regimen Treatment Adherence Scale-Prophylaxis), and kinesiophobia (Tampa Scale of Kinesiophobia). (3) Results: There were statistically significant differences in the domains Role-Physical (p < 0.001), Bodily Pain (p < 0.001), Role-Emotional (p < 0.001), Vitality (p = 0.04), and Social Functioning (p = 0.01) and the total scores, Physical Health (p < 0.001) and Mental Health (p < 0.001) on perceived quality of life. There were significant differences in the domains Skipping (p < 0.01), Communicating (p < 0.001), and the total score (p = 0.01) in terms of adherence. There were also significant differences in kinesiophobia (p = 0.02) after the study period. (4) Conclusions: EHL prophylaxis can improve the perceived quality of life of people with hemophilia. This prophylactic regimen, which requires fewer infusions, may improve adherence to treatment in adult patients with hemophilia over a 12-month period. The administration of extended half-life factor VIII concentrates can reduce kinesiophobia in adult patients with hemophilic arthropathy.

Incidence and treatment-related risk factors of inhibitor development after intensive FVIII replacement for major orthopaedic surgery in previous treated haemophilia A

INTRODUCTION

Haemophilia A (HA) is an X-linked recessive bleeding disorder caused by lack or deficiency of coagulation factor VIII.

AIM

The aim of this study is to determine the incidence and treatment-related risk factors of inhibitor development after intensive FVIII replacement for major orthopaedic surgery in previous treated persons with HA.

METHODS

A total of 151 HA who underwent 221 major orthopaedic surgical procedures after intensive FVIII treatment were reviewed. The results of inhibitor tests were collected. Potential clinical risk factors for inhibitor development were analyzed.

RESULTS

111 people were diagnosed with severe HA. Thirty-seven persons (24.5%) had history of previous intensive FVIII treatment for surgical procedure. They received a mean perioperative cumulative FVIII of 498 iu/kg within first week after surgery. Seven cases (4.6%) developed an inhibitor post-operatively in our study. Surgical procedure for pseudotumor and the group of persons who experienced postoperative complications had the higher incidence of inhibitor development (9.5%, 13.3% respectively). Only previous history for intensive FVIII exposure was considered as a significant predictor for postoperative inhibitor development after multivariate logistic regression analysis (OR: 29.5, P = 0.002).

CONCLUSION

The incidence of inhibitor development in previously treated persons with HA undergoing major orthopaedic surgery was 4.6% and the history of previous intensive FVIII treatment for surgery was associated with higher risk of inhibitor development.

CRISPR-Cas9 system: a novel and promising era of genotherapy for beta-hemoglobinopathies, hematological malignancy, and hemophilia

Gene therapy represents a significant potential to revolutionize the field of hematology with applications in correcting genetic mutations, generating cell lines and animal models, and improving the feasibility and efficacy of cancer immunotherapy. Compared to different genetic engineering tools, clustered regularly interspaced short palindromic repeats (CRISPR) CRISPR-associated protein 9 (Cas9) emerged as an effective and versatile genetic editor with the ability to precisely modify the genome. The applications of genetic engineering in various hematological disorders have shown encouraging results. Monogenic hematological disorders can conceivably be corrected with single gene modification. Through the use of CRISPR-CAS9, restoration of functional red blood cells and hemostasis factors were successfully attained in sickle cell anemia, beta-thalassemia, and hemophilia disorders. Our understanding of hemato-oncology has been advanced via CRIPSR-CAS9 technology. CRISPR-CAS9 aided to build a platform of mutated genes responsible for cell survival and proliferation in leukemia. Therapeutic application of CRISPR-CAS9 when combined with chimeric antigen receptor (CAR) T cell therapy in multiple myeloma and acute lymphoblastic leukemia was feasible with attenuation of CAR T cell therapy pitfalls. Our review outlines the latest literature on the utilization of CRISPR-Cas9 in the treatment of beta-hemoglobinopathies and hemophilia disorders. We present the strategies that were employed and the findings of preclinical and clinical trials. Also, the review will discuss gene engineering in the field of hemato-oncology as a proper tool to facilitate and overcome the drawbacks of chimeric antigen receptor T cell therapy (CAR-T).

A pipeline for the development and analysis of extracellular vesicle-based transcriptomic biomarkers in molecular diagnostics

Extracellular vesicles are shed by every cell type and can be found in any biofluid. They contain different molecules that can be utilized as biomarkers, including several RNA species which they protect from degradation. Here, we present a pipeline for the development and analysis of extracellular vesicle-associated transcriptomic biomarkers that our group has successfully applied multiple times. We highlight the key steps of the pipeline and give particular emphasis to the necessary quality control checkpoints, which are linked to numerous available guidelines that should be considered along the workflow. Our pipeline starts with patient recruitment and continues with blood sampling and processing. The purification and characterization of extracellular vesicles is explained in detail, as well as the isolation and quality control of extracellular vesicle-associated RNA. We point out the possible pitfalls during library preparation and RNA sequencing and present multiple bioinformatic tools to pinpoint biomarker signature candidates from the sequencing data. Finally, considerations and pitfalls during the validation of the biomarker signature using RT-qPCR will be elaborated.

Genetics and Epigenetics in Acquired Hemophilia A: From Bench to Bedside

Acquired hemophilia A (AHA) is a bleeding disorder characterized by the immunological inhibition of factor VIII (FVIII) of the hemostatic pathway leading to hemorrhagic events. Different domains of FVIII are the target of autoantibodies (mainly immunoglobulin (Ig) G) leading to the deficiency of FVIII. Several factors have been associated with the activation of the auto-immunity towards FVIII. Emerging evidence implicates CD4+ T cell activation in mediating this autoimmune response, with their involvement like that observed in congenital hemophilia A. Several genes such as HLA II DRB*16, DQB1*0502, and CTLA-4 + 49 are responsible for the pathogenesis of AHA. Epigenetic modifications and mainly long-coding RNAS (lncRNAs) are potentially contributing to the pathogenesis of AHA. The treatment approach of AHA includes the management of acute bleeding events and the administration of immunosuppressive medications. This review aimed to summarize the published data on the genetics and epigenetics of AHA. The severity and the mortality of this disease are creating an emerging need for further research in the field of the genetics and epigenetics of acquired hemorrhagic disorder.

Impact of Replacement Therapy on Pregnancy Outcomes in Hemophilia Carriers: A Historical Cohort Study in Saudi Arabia

This retrospective cohort study evaluates the safety and efficacy of replacement therapy with regard to pregnancy outcomes in hemophilia carriers. Hemophilia carriers face elevated bleeding risks during pregnancy, necessitating meticulous management, including replacement therapy with clotting factors. This research examines the records of 64 pregnant hemophilia carriers at King Fahad Medical City, Riyadh, from January 2010 to December 2023, analyzing their demographic details, hemophilia type and severity, replacement therapy specifics, and pregnancy outcomes. The study found that 62.5% of the participants had hemophilia A, with 43.8% categorized as severe. Most subjects (87.5%) received recombinant factor VIII at a median dosage of 30 IU/kg weekly. Adverse pregnancy outcomes included gestational hypertension (15.6%), preterm labor (18.8%), and postpartum hemorrhage (12.5%). The cesarean section rate was 28.1%. Neonatal outcomes were generally favorable, with median birth weights at 3100 g and mean Apgar scores of 8.2 and 9.1 at 1 and 5 min, respectively. Logistic regression analysis revealed no significant association between adverse events and therapy type or dosage, though a trend towards significance was noted with once-weekly administration (p = 0.082). The study concludes that replacement therapy is a viable method for managing hemophilia in pregnant carriers, leading to generally favorable maternal and neonatal outcomes. However, it underscores the importance of individualized treatment plans and close monitoring to effectively manage the risks associated with hemophilia during pregnancy.

Gene therapy: principles, challenges and use in clinical practice

INTRODUCTION

Gene therapy is an emerging topic in medicine. The first products have already been licensed in the European Union for the treatment of immune deficiency, spinal muscular atrophy, hemophilia, retinal dystrophy, a rare neurotransmitter disorder and some hematological cancers, while many more are being assessed in preclinical and clinical trials.

OBJECTIVE

The purpose of this review is to provide an overview of the core principles of gene therapy along with information on challenges and risks. Benefits, adverse effects and potential risks are illustrated based on the examples of hemophilia and spinal muscular atrophy.

RESULTS

At present, in-vitro and in-vivo gene addition or gene augmentation is the most commonly established type of gene therapy. More recently, more sophisticated and precise approaches such as in situ gene editing have moved into focus. However, all types of gene therapy require long-term observation of treated patients to ensure safety, efficacy, predictability and durability. Important safety concerns include immune reactions to the vector, the foreign DNA or the new protein resulting from gene therapy, and a remaining low cancer risk based on insertional mutagenesis. Ethical and regulatory issues need to be addressed, and new reimbursement models are called for to ease the financial burden that this new treatment poses for the health care system.

CONCLUSION

Gene therapy holds great promise for considerable improvement or even cure of genetic diseases with serious clinical consequences. However, a number of questions and issues need to be clarified to ensure broad accessibility of safe and efficacious products.

The good, the bad and the ugly of pain in haemophilia: Recent evidence on the epidemiology, molecular mechanisms and knowledge gaps preventing optimal treatment

INTRODUCTION

Haemophilia is an inherited, X-linked blood clotting disorder caused by the deficiency of coagulation factors VIII (FVIII, haemophilia A) or IX (FIX, haemophilia B). Spontaneous bleeds are common in severe forms of haemophilia and can also occur in moderate and mild haemophilia. Severe or repeated bleeding at a joint can evolve into chronic haemophilic arthropathy, with functional damage of the joint, disability, and intense chronic articular pain. Nonetheless, acute and chronic pain may emerge due to secondary conditions related to bleedings.

AIM

This narrative review aims to critically discuss the most recent evidence about pain in haemophilia to give healthcare professionals a clear picture of current knowledge hence favouring the optimisation of clinical management of pain.

METHODS

Extensive literature search with the terms 'hemophilia' AND 'pain', focusing on the time window 2021-2023.

RESULTS

Acute and chronic pain is a critical aspect of haemophilia at all ages. It should be considered a multifaceted phenomenon, with a positive role as an early emergency signal of a clinical event (haemarthrosis), and numerous detrimental aspects linked to its burden that heavily affects the health-related quality of life, with psychological and social consequences.

CONCLUSION

Despite its prevalence and frequency in people with haemophilia, pain is often underestimated by healthcare professionals, leading to insufficient and inadequate treatment, also due to uncertainty linked to the presence of the coagulation disorder or arthritic flares.

Using evidence-based co-design to develop a hybrid delivered exercise intervention that aims to increase confidence to exercise in people with haemophilia

INTRODUCTION

Due to advances in treatments, people with haemophilia (PWH) are living longer. They are not as active as the general population due to joint damage and lack confidence to be active due to concerns about further bleeds and pain. There is a need to facilitate healthy aging through promotion of physical activity (PA) and exercise. Changing patient beliefs and increasing physical literacy and confidence to move are thought to be key to helping PWH become more active.

AIM

This paper describes the development of an exercise and behaviour change intervention to improve confidence to exercise in PWH.

METHODS

The 4-stage Medical Research Council framework for complex intervention development was used.

RESULTS

Stakeholders included 17 PWH and 7 physiotherapists working in haemophilia. Seven online focus group meetings were held. The final intervention is a hybrid 12-week physiotherapist led progressive exercise programme. Classes are 45 min including Pilates, High intensity interval training and balance elements, together with discussion sessions focusing on PA recommendations, the types and benefits of different exercise styles and the effects of PA, together with the effects of aging for PWH. The COM-B model of behaviour change was used to develop the intervention.

CONCLUSION

Co-design helps to produce an intervention that understands the stakeholders needs. Through this process the intervention developed to incorporate not only increasing PA but also confidence to exercise. The use of behaviour change theory identified the behaviour techniques included in the intervention and aims to increase physical literacy in this population.

Delivery of DNA-Based Therapeutics for Treatment of Chronic Diseases

Gene therapy and its role in the medical field have evolved drastically in recent decades. Studies aim to define DNA-based medicine as well as encourage innovation and the further development of novel approaches. Gene therapy has been established as an alternative approach to treat a variety of diseases. Its range of mechanistic applicability is wide; gene therapy has the capacity to address the symptoms of disease, the body's ability to fight disease, and in some cases has the ability to cure disease, making it a more attractive intervention than some traditional approaches to treatment (i.e., medicine and surgery). Such versatility also suggests gene therapy has the potential to address a greater number of indications than conventional treatments. Many DNA-based therapies have shown promise in clinical trials, and several have been approved for use in humans. Whereas current treatment regimens for chronic disease often require frequent dosing, DNA-based therapies can produce robust and durable expression of therapeutic genes with fewer treatments. This benefit encourages the application of DNA-based gene therapy to manage chronic diseases, an area where improving efficiency of current treatments is urgent. Here, we provide an overview of two DNA-based gene therapies as well as their delivery methods: adeno associated virus (AAV)-based gene therapy and plasmid DNA (pDNA)-based gene therapy. We will focus on how these therapies have already been utilized to improve treatment of chronic disease, as well as how current literature supports the expansion of these therapies to treat additional chronic indications in the future.