Optimal treatment strategies for hemophilia: achievements and limitations of current prophylactic regimens

Emicizumab for All Pediatric Patients with Severe Hemophilia A

Emicizumab is the first approved nonreplacement therapy for bleeding prophylaxis in hemophilia A (HA) patients. In 2018, it was licensed for HA patients with inhibitors, subsequently followed by an "European Medicines Agency (EMA)" approval for patients with severe HA in the absence of inhibitors in 2019. This is immediately raising the question whether emicizumab is suitable as a first-line treatment for all pediatric patients with severe HA. In this review, we want to discuss what we have, what we know, and what we would like to know. Severe HA is characterized by severe spontaneous and traumatic bleedings, particularly into muscles and joints leading to chronic joint damage. Standard of care is the regular, prophylactic replacement of factor VIII to prevent bleedings. Due to approval of emicizumab-the first nonreplacement therapy for bleeding prophylaxis-in HA patients with inhibitors, and severe HA patients without inhibitors, it is of pivotal interest whether emicizumab could be the first-line treatment in all pediatric patients with severe HA. Clinical trials and real-world observational studies could demonstrate a good efficacy and safety for bleeding prevention during emicizumab treatment in HA patients with and without inhibitors. This clearly indicates that emicizumab could improve HA treatment. However, some crucial and critical questions are remaining with regard to the use of emicizumab. Some of this missing information is already under investigation in the context of clinical trials. Until getting finalized data to shed insights into the points that are currently being discussed, there is a variety of expert and expert group recommendations, which are tackling questions concerning the treatment of HA patients. This review will address major information that is already available, but will also focus on important points that remain to be elucidated in the context of HA treatment.

Most subjectively affected joints in patients with haemophilia - what has changed after 20 years in Germany?

BACKGROUND

In patients with haemophilia (PwH), most frequently affected joints are the ankle, knee and elbow. Due to improved factor therapy in the last decades, these previous findings have to be verified in Germany.

AIM

The aim of this study is to detect the most affected joint, evaluate the significance of the source of pain and determine the point prevalence of back pain in Germany today.

PATIENTS AND METHODS

In a retrospective study, data of n = 300 patients with severe moderate and mild haemophilia were evaluated regarding the most affected joint, the most common source of pain, and the point prevalence of back pain. An anamnesis questionnaire and the German Pain Questionnaire were used for this assessment.

RESULTS

The most affected joint in German PwH is still the ankle (41%), followed by the knee (27%) and the elbow (11%). The most common source of pain is also the ankle joint (32%). Back pain was also identified as one of the most common sources of pain, which is comparable to the elbow (elbow:15%; back:13%). The point prevalence in PwH for back pain was significantly higher compared to the general German population (P = .031).

CONCLUSION

Our data showed that the ankle is still the most affected joint and the most common source of pain in Germany. These results also showed the relevance of back pain as a pain source. The evaluations also demonstrated the high point prevalence of back pain in PwH. Future therapies should also focus on the spine because joint changes affect posture.

Gaining more insight into ankle pain in haemophilia: A study exploring pain, structural and functional evaluation of the ankle joint

INTRODUCTION

Ankle arthropathy is highly prevalent among people with haemophilia (PwH), even with prophylaxis, and leads to pain and disability. Mechanisms and consequences of painful symptoms related to ankle arthropathy have not been extensively studied.

METHODS

A consecutive sample of 30 adult PwH was included (60 ankles). Ankle structure was assessed with magnetic resonance imaging (IPSG-MRI) and ultrasound (HEAD-US). The HJHS 2.1 assessed function of ankles and knees. Physical functioning was assessed with the Timed Up and Go test, the 2-Minute Walking Test and activity limitations with the HAL questionnaire. Health-related quality of life was evaluated using the EQ-5D-5L questionnaire. Overall pain severity was examined using the Brief Pain Inventory questionnaire and ankle pain intensity with a visual analogue scale. Pressure pain thresholds with an algometer assessed pain sensitivity. Spearman correlations were used to calculate interrelations between joint structure, function and pain.

RESULTS

Twenty-five PwH (83%) reported ≥1 painful joint, with 67% reporting the ankle as most painful joint. MRI-confirmed abnormalities were seen in 76% of talocrural and 55% of subtalar joints. HEAD-US abnormalities were seen in 93% of the ankles. A large variation was seen in pain sensitivity at the ankle. While moderate to high correlations were observed between ankle structure and HJHS, no meaningful correlations were found between MRI-scores and pain intensity or sensitivity.

CONCLUSIONS

Structural joint damage is present in many ankles but is not related to pain in PwH. Further studies should consider somatosensory nervous system dysfunction in PwH as contributing factor to painful ankle arthropathy.

Peak pressure during gait in patients with severe haemophilia: A controlled cross-sectional study

BACKGROUND

Patients with severe haemophilia suffer from bleeding-related joint changes in which the ankle joint is most frequently affected. In the resulting gait changes, the forefoot is involved by reducing the foot pressure. However, it is unclear which changes in foot pressure are present in the individual's foot zones.

RESEARCH QUESTION

The aim of the study was to determine whether compensation mechanisms are present in the foot zones regarding the peak pressure under dynamic conditions and to identify possible underlying mechanisms for gait changes.

METHODS

In a controlled cross-sectional study, a pedobarography was performed during gait with a standardized speed (3 km/h) in patients with haemophilia (PwH;n = 40) and healthy controls (Con;n = 40). Pressure pain thresholds (PPT) were detected, and Haemophilia Joint Health Score (HJHS) was performed to determine the current joint status.

RESULTS

PwH showed a decreased peak pressure in metatarsals II-IV and heel compared to Con. Patients with major-affected ankle joints (determined with the HJHS) showed a decreased single-step length, stride-length and stride-time. Accordingly, the cadence was increased by 10 ± 11 steps/min in PwH compared to Con. Furthermore, PwH showed decreased ankle range of motion (ROM) in HJHS and an altered pain perception due to reduced PPT.

SIGNIFICANCE

PwH showed a changed gait pattern in peak pressure compared to Con. A restricted rolling behavior, which might be caused by movement restrictions and pain sensation, leads to reduced pressure in the center forefoot, resulting in a shorter stride-length. Future therapies should focus on maintaining joint mobility for better rolling behavior and improving ankle joints' stability to achieve a balanced load between the midfoot, heel, and forefoot. The use of insoles adapted to our data, based on group differences between PwH and Con, could be supportive in this case.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Recombinant single-chain factor VIII in severe hemophilia: Long-term safety and efficacy in previously treated patients in the AFFINITY extension study

BACKGROUND

rVIII-SingleChain is a recombinant single-chain factor VIII used to treat people with hemophilia A.

OBJECTIVES

The aim of this extension study was to investigate the long-term safety and efficacy of rVIII-SingleChain prophylaxis in ≥200 previously treated patients (PTPs) with hemophilia A with ≥100 exposure days (EDs).

METHODS

In total, 222 patients were enrolled, of which 204 rolled over from prior rVIII-SingleChain studies. The median age was 21 years (range, 2-65 years), including 155 patients ≥12 years and 67 patients <12 years. Patients continued with their previously assigned dose and regimen, or switched at the investigator's discretion. Patients were treated for a mean duration of 31 months (range, 1-47 months), the mean ED was 342 (standard deviation, 135.5), and 212 (95.5%) patients achieved >100 EDs. When the study ended, most patients were on either a prophylaxis regimen of 34.9 (17-62) IU/kg, 3×/week (N = 88; 39.6%), or 37.2 (13-65) IU/kg, 2×/week regimen (N = 72; 32.4%).

RESULTS

Hemostatic efficacy was rated excellent or good in 87.1% of assessed bleeds. The median (range) annualized bleeding rate was 1.21 (0.0-42.6), and the annualized spontaneous bleeding rate (AsBR) was 0.32 (0.0-33.0) for prophylaxis regimens. Median AsBR was similar for patients treated 3×/week and 2×/week (0.31 and 0.30, respectively). Surgical hemostatic efficacy was rated excellent or good in 100% of surgeries. No inhibitors, anaphylactic reactions, or thromboembolic events were reported in PTPs.

CONCLUSION

These results confirm the safety and efficacy of rVIII-SingleChain as a long-term prophylaxis treatment modality for PTPs with severe hemophilia A.

The Hemophilia Joint Health Score version 2.1 Validation in Adult Patients Study: A multicenter international study

Background

The Hemophilia Joint Health Score (HJHS) was developed and validated to detect arthropathy in children. Additional evidence is required to show validity in adults. We studied the convergent and discriminant construct validity of the HJHS version 2.1(HJHSv2.1) in adults with hemophilia. A secondary aim was to define age-related normative adult HJHSv2.1 reference values.

Methods

We studied 192 adults with hemophilia, and 120 healthy adults in four age-matched groups-18 to 29, 30 to 40, 41 to 50, and >50 years-at nine centers. Trained physiotherapists scored the HJHS and World Federation of Hemophilia (WFH) joint score. Health history, the Functional Independence Scale of Hemophilia (FISH), Hemophilia Activities List (HAL), and Short-Form McGill Pain Questionnaire (SF-MPQ) were also collected.

Results

The median age was 35.0 years. Of participants with hemophilia, 68% had severe, 14% moderate, and 18% mild disease. The HJHS correlated strongly with WFH score (Spearman's rho [rs ] = .95, P < .001). Moderate correlations were seen between the FISH (rs  = .50, P < .001) and SF-MPQ Present Pain Intensity (rs  = .50, P < .001), while a modest correlation was found with the HAL (rs  = -.37, P < .001). The HJHS significantly differentiated between age groups (Kruskal-Wallis T = 35.02, P < .001) and disease severity in participants with hemophilia. The HJHS had high internal reliability (Cronbach's α = .88). We identified duration of swelling as a redundant item in the HJHS.

Conclusions

The HJHS shows evidence of strong convergent and discriminant construct validity to detect arthropathy in adults with hemophilia and is well suited for use in this population.

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

Background

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

Objective

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

Methods

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

Results

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

Conclusions

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

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

OBJECTIVES

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

DESIGN

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

SETTING

England, Wales and Scotland, UK.

PARTICIPANTS

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

PRIMARY AND SECONDARY OUTCOMES

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

RESULTS

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

CONCLUSION

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

Exploration of the minimum necessary FVIII level at different physical activity levels in pediatric patients with hemophilia A

BACKGROUND

Physical activity can increase joint stability and reduce the risk of injury in hemophilia patients. There is limited clinical data on target trough FVIII levels during physical activity in hemophilia A patients. Hence, this study aimed to explore the target trough FVIII level required to avoid bleeding during different physical activities in hemophilia A patients.

METHODS

Patients with severe or moderate hemophilia A, who underwent pharmacokinetics (PK) tests at our center were enrolled in this study. Physical activities and clinical information such as bleeding were recorded. The FVIII level during physical activity was calculated by the WAPPS-Hemo.

RESULTS

A total of 105 patients were enrolled in this study. A total of 373 physical activities were recorded, of which 57.6% (215/373) was low-risk activities and the remaining 42.4% (158/373) was medium-risk activities. Most common physical activities were bicycling (59.0%), swimming (43.8%), running (48.6%), and jumping rope (41.0%). The FVIII trough level of low-risk physical activity was 3.8 IU/dl (AUC = 0.781, p = 0.002) and moderate-risk physical activity was 7.7 IU/dl (AUC = 0.809, p < 0.001). FVIII trough levels [low-risk activities: 6.1 (3.1, 13.2) IU/dl vs. 7.7 (2.3, 10.5) IU/dl, moderate-risk activities: 9.6 (5.8, 16.9) IU/dl vs. 10.2 (5.5, 11.0) IU/dl] were not statistically different between the mild arthropathy group and the moderate-severe arthropathy group. Multiple bleeding risk tended to increase with physical activities classified as moderate-risk (OR [95% CI]: 3.815 [1.766-8.238], p = 0.001).

CONCLUSION

The minimum necessary FVIII level increased with higher risk physical activity, irrespective of arthropathy.

The EANM guideline for radiosynoviorthesis

PURPOSE

Radiosynoviorthesis (RSO) using the intraarticular application of beta-particle emitting radiocolloids has for decades been used for the local treatment of inflammatory joint diseases. The injected radiopharmaceuticals are phagocytized by the superficial macrophages of the synovial membrane, resulting in sclerosis and fibrosis of the formerly inflamed tissue, finally leading to reduced joint effusion and alleviation of joint pain.

METHODS

The European Association of Nuclear Medicine (EANM) has written and approved these guidelines in tight collaboration with an international team of clinical experts, including rheumatologists. Besides clinical and procedural aspects, different national legislative issues, dosimetric considerations, possible complications, and side effects are addressed.

CONCLUSION

These guidelines will assist nuclear medicine physicians in performing radiosynoviorthesis. Since there are differences regarding the radiopharmaceuticals approved for RSO and the official indications between several European countries, this guideline can only give a framework that must be adopted individually.

Promoting physical activity in people with haemophilia: the MEMO (Movement for persons with haEMOphilia) expert consensus project

Regular physical activity can increase joint stability and function, reduce the risk of injury, and improve quality of life of people with haemophilia (PwH). However, a recent review of the literature shows that appropriate physical activity and sport are not always promoted enough in the overall management of PwH. A group of Italian experts in haemophilia care undertook a consensus procedure to provide practical guidance on when and how to recommend physical exercise programmes to PwH in clinical practice. Three main topics were identified -haemophilia and its impact on movement, physical activity recommendations for PwH, and choice and management of sports activity in PwH- and ten statements were formulated. A modified Delphi approach was used to reach a consensus. The group also created practical tools proposing different physical activities and frequencies for different age groups, the Movement Pyramids, to be shared and discussed with patients and caregivers. In conclusion, in the opinion of the working group, physical activity can be considered as a low-price intervention that can prevent/reduce the occurrence of chronic diseases and should be further encouraged in PwH to obtain multiple physical and psychological benefits. Future research should include prospective studies focusing on participation in sports, specific risk exposure and clinical outcomes.

[Treatment of haemophilia: From replacement to gene therapy]

Haemophilia A and B are congenital bleeding disorders characterized by missing or defective factor VIII or factor IX, respectively. Factor replacement therapy has been the gold standard for prophylaxis and treatment of bleeding complications. However, the inconvenience of regular intravenous administration, along with progression of arthropathy and development of inhibitors has driven the need for alternative treatment options, such as extended half-life products, non-factor coagulation products, such as subcutaneous emicizumab, blocking natural anticoagulants (rebalancing haemostatic agents) and gene therapy, which have been useful to control bleeding or are currently under late-phase clinical investigation.

Diagnosis and treatment of chronic synovitis in patients with haemophilia: consensus statements from the Italian Association of Haemophilia Centres

Although synovitis is recognized as a marker of joint disease activity, its periodic assessment is not included in routine clinical surveillance of patients with haemophilia (PwH). In order to evaluate the current knowledge and to identify controversial issues, a preliminary literature search by the Musculoskeletal Committee of the Italian Association of Haemophilia Centres (AICE) has been conducted. Statements have been established and sent to the Italian AICE members to collect their level of agreement or disagreement by a Delphi process. Thirty‐seven consensus recommendations have been drafted. We found a general agreement on the indication to consider the presence of synovitis as a marker of joint disease activity in PwH. Accordingly, there was agreement on the indication to search for synovitis both in patients reporting joint pain and in asymptomatic ones, recognizing ultrasound as the most practical imaging technique to perform periodic joint screening. Interestingly, after detection of synovitis, there was agreement on the indication to modify the therapeutic approach, suggesting prophylaxis in patients treated on demand and tailoring treatment in patients already under prophylaxis. Whereas the need of an early consultation with a physiotherapist is recommended for PwH affected by chronic synovitis, the exact timing for an orthopaedic surgeon consultation is currently unknown.

Hemophilia A Gene Therapy: Current and Next-Generation Approaches

INTRODUCTION

: Hemophilia comprises a group of X-linked hemorrhagic disorders that result from a deficiency of coagulation factors. The disorder affects mainly males and leads to chronic pain, joint deformity, reduced mobility, and increased mortality. Current therapies require frequent administration of replacement clotting factors, but the emergence of alloantibodies (inhibitors) diminishes their efficacy. New therapies are being developed to produce the deficient clotting factors and prevent the emergence of inhibitors.

AREAS COVERED

: This article provides an update on the characteristics and disease pathophysiology of hemophilia A, as well as current treatments, with a special focus on ongoing clinical trials related to gene replacement therapies.

EXPERT OPINION

: Gene replacement therapies provide safe, durable, and stable transgene expression while avoiding the challenges of clotting factor replacement therapies in patients with hemophilia. Improving the specificity of the viral construct and decreasing the therapeutic dose are critical toward minimizing cellular stress, induction of the unfolded protein response, and the resulting loss of protein production in liver cells. Next-generation gene therapies incorporating chimeric DNA sequences in the transgene can increase clotting factor synthesis and secretion, and advance the efficacy, safety, and durability of gene replacement therapy for hemophilia A as well as other blood clotting disorders.

Italian experience with rVIII-single chain: a survey of patients with haemophilia A and their physicians

rVIII-SingleChain is indicated for treatment and prophylaxis of bleeding in patients with haemophilia A (HA). The safety and efficacy of rVIII-SingleChain have previously been shown in the AFFINITY clinical trial programme. This survey evaluated clinical experience following a switch to rVIII-SingleChain from the perspective of both physicians and patients. A web-based survey (July–September 2019) involving 14 Haemophilia Treatment Centres (HTCs) collected data about HA patients who were under treatment with rVIII-SingleChain for ≥ 12 months, as reported by their physicians. In addition, about half of these patients were separately interviewed. Out of 91 patients receiving rVIII-SingleChain in the 14 participating HTCs, 48 had been treated for ≥ 12 months; among those 48, 38% were ≤ 18 years, 37% 19–40 years and 25 % ≥ 41 years; 73% of them had severe HA and 85% were being treated with prophylactic therapy. Twenty-six patients accepted to be separately interviewed: mean age was 30 years; 62% had severe HA and 85% were receiving prophylaxis. Focusing on those patients who were already in prophylaxis with prior FVIII (all but one with recombinant factors), infusion frequency was significantly reduced from 3–2 per week following the switch to rVIII-SingleChain (mean, 2.74 vs. 2.44, respectively; p=0.013), as reported by physicians; the rate of patients needing 3 infusions per week dropped from 74% with previous products to 44% with rFVIII-SingleChain. The annual mean factor consumption was 4740 IU/Kg (median, 4500 IU/Kg; min, 2.215 IU/Kg; max, 7.200 IU/Kg) with prior product and 4320 IU/Kg (median, 4320 IU/Kg; min, 2.215 IU/Kg; max, 6.646 IU/Kg) with rVIII-SingleChain. Both physicians and patients reported a significant reduction in annual total bleeding rates with rVIII-SingleChain compared with prior product (mean 2.15–0.96 and 2.46–0.71 events/year, p = 0.031 and p = 0.018, respectively). Mean satisfaction ratings (from 1; dissatisfied, to 5; very satisfied) for rVIII-SingleChain were quite high for both physicians (4.14, 86% satisfied/very satisfied) and patients (4.18, 86% satisfied/very satisfied). This survey suggested that switching to rVIII-SingleChain allowed patients to reduce their injection frequency without increasing factor consumption or compromising clinical results. Both physicians and patients reported a positive experience with rVIII-SingleChain after 1 year of treatment.

Clinical and Biomechanical Progression after Ankle Joint Distraction in a Young Adolescent Patient with Haemophilia

Ankle joint distraction (AJD) has been described to be a valuable joint-sparing alternative to arthrodesis or arthroplasty; however, clinical endpoints associated to this surgical intervention are lacking. The current case report describes clinical and biomechanical outcome measures of ankle joint distraction in a 14-year-old patient with severe haemophilia A. Because of persistent and incapacitating pain and the poor response to conservative and invasive treatment options, ankle joint distraction was performed in this 14-year-old patient using an external fixator encompassing two Ilizarov full rings in the tibia and a foot ring fixed to the foot by four K-wires. State-of-the-art medical imaging and non-invasive skin marker-based 3D multi-segment foot modelling were performed in a pre- and post-operative stage. From a structural viewpoint, this AJD was a success since it improved and stabilised the osteo-cartilaginous lesions of the ankle. Biomechanical outcome measures associated with the 18-month follow-up were found to be suboptimal, showing an early plantarflexion pattern at the ankle joint during midstance and a tendency towards increased power absorption at the midfoot with peak power absorption being almost two times higher when compared to boys of the same age. From a functional viewpoint, we observed a clear reduction in the patients’ physical activities until one year after AJD. Despite these functional and structural improvements, recurrent painful phenomena, including the development of a complex regional pain syndrome (CRPS) and a stress fracture of the third metatarsal bone, were observed which are probably related with the development of recurrent subchondral oedema.

Magnetic resonance imaging in boys with severe hemophilia A: Serial and end-of-study findings from the Canadian Hemophilia Primary Prophylaxis Study

BACKGROUND

This study examined the structural outcomes for joints of boys with severe hemophilia A receiving frequency/dose-escalated primary prophylaxis using magnetic resonance imaging (MRI), and the importance of interval MRI changes.

METHODS

Forty-six subjects (27 with interval studies) were evaluated by radiographs (X-rays) and mid- and end-of-study MRIs (using the International Prophylaxis Study Group scale), as part of the Canadian Hemophilia Prophylaxis Study. The primary outcome was the presence of MRI osteochondral findings.

RESULTS

The median (range) time on study at the end-of-study MRI examination was 9.6 (4.8-16.0) years, during which 18 of 46 subjects (39%) had osteochondral changes in at least one joint. An interval change in MRI score of at least 1 point was observed in 44% of joints (43 ankles, 21 elbows, 4 knees); at least one joint showed this change in all 27 subjects. Self-reported interval hemarthrosis was associated with a higher likelihood of interval osteochondral change (odds ratio [OR], 1.49; 95% confidence interval [CI] = 1.08-2.06). Presence of synovial hypertrophy or hemosiderin on interval MRIs was associated with an OR of 4.71 (95% CI, 1.92-11.57) and 5.25 (95% CI, 2.05-13.40) of later osteochondral changes on MRI.

DISCUSSION

MRI changes were seen in 39% of subjects. Interval index joint bleeding was associated with an increased risk of later MRI changes, and earlier soft-tissue changes were associated with subsequent osteochondral changes.

Prophylaxis in children with haemophilia in an evolving treatment landscape

INTRODUCTION

For children with haemophilia, early initiation of prophylaxis is crucial to prevent life-threatening bleeds and maintain joint health throughout life. Options for prophylaxis have recently increased from replacement therapy with standard or extended half-life coagulation factor products to include other haemostasis products, such as the non-replacement therapy emicizumab.

AIM

To review key factors that determine the choice of prophylaxis in young children.

METHODS

Key clinical questions on the implementation of prophylaxis for haemophilia in children were identified and PubMed was searched for evidence supporting guidance on the implementation of prophylaxis.

RESULTS

The results of the literature search and the practical experience of the authors were used to build consensus on when to start prophylaxis, the pros and cons of the products available to guide the choice of product, and practical aspects of starting prophylaxis to guide the choice of regimen.

CONCLUSIONS

In this era of increasing therapeutic choices, available information about the range of treatment options must be considered when initiating prophylaxis in young children. Parents or care givers must be sufficiently informed to allow informed shared decision making. Although plentiful data and clinical experience have been gathered on prophylaxis with clotting factor replacement therapy, its use in young children brings practical challenges, such as the need for intravenous administration. In contrast, our relatively brief experience and limited data with subcutaneously administered non-replacement therapy (i.e., emicizumab) in this patient group imply that starting emicizumab prophylaxis in young children requires careful consideration, despite the more convenient route of administration.

Improving assessment and management of pain in hemophilia: an Italian Delphi consensus statement

Comprehensive evidence-based guidelines and well-validated assessment scales for pain in people with hemophilia (PwH) are needed. Here, we report 28 statements covering five topics on pain assessment and management in pediatric and adult PwH that were developed by 60 Italian hemophilia specialists during a Delphi consensus process. Overall, a clear consensus was achieved for 19 of the 28 statements. Consensus was reached on all statements on the topic of pain assessment and quality of life (QoL), including the need for regular pain assessment on a quantitative scale, the importance of distinguishing between different pain types, and the need to evaluate the impact of pain on patient QoL. The other four topics concerned acute and chronic pain management in adults and in children. Consensus was reached on statements regarding non-pharmacologic treatment and the use of first-line paracetamol (acetaminophen). There was a lack of consensus regarding the use of non-steroidal anti-inflammatory drugs, cyclooxygenase-2 inhibitors, or opioids.

Design of the HEM-POWR study: a prospective, observational study of real-world treatment with damoctocog alfa pegol in patients with haemophilia A

INTRODUCTION

Haemophilia A is a rare bleeding disorder caused by defects in coagulation factor VIII (FVIII). Damoctocog alfa pegol (BAY 94-9027, Jivi, Bayer, Germany) is a site-specifically PEGylated, extended-half-life, recombinant FVIII, approved for use in previously treated patients (PTPs) aged ≥12 years with haemophilia A. However, a real-world evidence regarding routine clinical use of damoctocog alfa pegol is limited.

METHODS AND ANALYSIS

HEM-POWR is a multinational, multicentre, non-interventional, prospective, postmarketing cohort study evaluating the effectiveness and safety of real-world treatment with damoctocog alfa pegol. Estimated enrolment is ≥200 PTPs with haemophilia A, receiving damoctocog alfa pegol (on-demand, prophylaxis or intermittent prophylaxis (as per local label)), observed for 36 months. Primary outcomes are total bleeding events and annualised bleeding rate; secondary outcomes include long-term safety, joint health, pharmacokinetics, patient-reported outcomes (PROs) from validated questionnaires and perioperative haemostasis. Where applicable, reasons for switching to damoctocog alfa pegol, choice of treatment regimen and dose will also be captured. Exploratory and descriptive statistical analyses will be performed, and will be stratified by parameters including, but not limited to, prophylaxis regimen and haemophilia severity. Patients can record bleeds and consumption in electronic (e) Diaries, ePROs, and can access non-promotional study information (videos explaining study procedures) via an online patient portal. Optionally, patients can enrol in the LIFE-ACTIVE substudy designed to investigate the relationship between activity (measured by the ActiGraph CP Insight watch) and effectiveness parameters collected from HEM-POWR.

ETHICS AND DISSEMINATION

Study approval was obtained by local independent ethics committees and authorities in participating study centres across Europe, the Americas and Asia. Informed consent from patients or their legal representative is a requirement for participation. The study results will be submitted for publication in a peer-reviewed scientific journal and presented at scientific conferences.

TRIAL REGISTRATION NUMBERS

NCT03932201, EUPAS26416.

PROTOCOL VERSION AND DATE

V.1.2, 27 September 2019.

Considerations on activity assay discrepancies in factor VIII and factor IX products

New modified coagulation factor VIII (FVIII) and factor IX (FIX) products have been designed to improve the treatment of individuals with hemophilia A and B by increasing the interval between dosing. Although these FVIII and FIX molecules have been structurally modified to improve the circulation time, the changes have also influenced their behavior in functional assays in comparison with traditional plasma-derived or recombinant coagulation factors. The assignment of potencies for these products can be problematic because discordance in factor activity values between the commonly used one-stage clotting and chromogenic substrate assays is often observed. Discrepancies in potency assay values also exist when different assay kits and reagents are used in the same assay type. Ideally, all FVIII and FIX products should be calibrated against the World Health Organization (WHO) International Standards (IS) because the assignment of potencies in international units (IU) helps maintain treatment tradition and meaningful references for manufacturers, patients, and clinicians. The discrepant measurements, attributed to the modified structural and functional properties of these products, are manifested in their lack of commutability with the WHO IS for FVIII or FIX. Herein, we discuss the considerations upon which an assay is chosen for potency assignment and postadministration monitoring of a new factor product, which include the validity of the assay calibrated with the IS, the meaning of the potency values in IU, standards of care for patients, clinical relevance between the assigned potency value and recovery value from clinical laboratories, and patient safety.

Current therapeutic approaches in the management of hemophilia-a consensus view by the Romanian Society of Hematology

Hemophilia A (HA) and hemophilia B (HB) are rare disorders, being caused by the total lack or under-expression of two factors from the coagulation cascade coded by genes of the X chromosome. Thus, in hemophilic patients, the blood does not clot properly. This results in spontaneous bleeding episodes after an injury or surgical intervention. A patient-centered regimen is considered optimal. Age, pharmacokinetics, bleeding phenotype, joint status, adherence, physical activity, personal goals are all factors that should be considered when individualizing therapy. In the past 10 years, many innovations in the diagnostic and treatment options were presented as being either approved or in development, thus helping clinicians to improve the standard-of-care for patients with hemophilia. Recombinant factors still remain the standard of care in hemophilia, however they pose a challenge to treatment adherence because they have short half-life, which where the extended half-life (EHL) factors come with the solution, increasing the half-life to 96 hours. Gene therapies have a promising future with proven beneficial effects in clinical trials. We present and critically analyze in the current manuscript the pros and cons of all the major discoveries in the diagnosis and treatment of HA and HB, as well as identify key areas of hemophilia research where improvements are needed.

Incidence and mortality rates of intracranial hemorrhage in hemophilia: a systematic review and meta-analysis

Intracranial hemorrhage (ICH) is a severe complication that is relatively common among hemophilia patients. This systematic review aimed to obtain more precise estimates of ICH incidence and mortality in hemophilia, which may be important for patients, caregivers, researchers and health policy-makers. PubMed and EMBASE were systematically searched using terms related to "hemophilia" and "intracranial hemorrhage" or "mortality". Studies that allowed calculation of ICH incidence or mortality rates in a hemophilia population of at least 50 patients were included. We summarized evidence on ICH incidence and calculated pooled ICH incidence and mortality in three age groups: (1) persons of all ages with hemophilia, (2) children and young adults below 25 years of age with hemophilia and (3) neonates with hemophilia. Incidence and mortality were pooled with a Poisson-Normal model or a Binomial-Normal model. We included 45 studies that represented 54 470 patients, 809 151 person-years and 5326 live births of hemophilia patients. In persons of all ages, the pooled ICH incidence and mortality rates were 2.3 (95% CI 1.2-4.8) and 0.8 (95% CI 0.5-1.2) per 1000 person-years, respectively. In children and young adults, the pooled ICH incidence and mortality rates were 7.4 (95% CI 4.9-11.1) and 0.5 (95% CI 0.3-0.9) per 1000 person-years, respectively. In neonates, the pooled cumulative ICH incidence was 2.1% (95% CI 1.5-2.8) per 100 live births. ICH was classified as spontaneous in 35-58% of cases. Our findings suggest that ICH is an important problem in hemophilia that occurs among all ages, requiring adequate preventive strategies.

Regulation and importance of factor VIII levels in hemophilia A carriers

PURPOSE OF REVIEW

To summarize the recent literature related to female hemophilia A carriers with respect to prevalence in the population, the impact of baseline factor VIII levels and other influences on bleeding phenotype, and clinical management needs.

RECENT FINDINGS

Many female hemophilia A carriers are at risk for abnormal bleeding, yet they are underrecognized by healthcare providers and their bleeding symptoms are underreported. Low FVIII levels are consistently associated with clinically significant bleeding and correlate well with skewed X chromosome inactivation (XCI). Most interestingly, bleeding tendency is also observed in some hemophilia A carriers with normal factor VIII levels and requires further investigation. Well controlled studies investigating peripartum and periprocedural FVIII levels and adequate hemostatic treatment are necessary to inform management guidelines.

SUMMARY

Prevalence and bleeding tendency of hemophilia A carriers remain underreported, despite a significant proportion having low FVIII levels. Skewed XCI may explain low FVIII but does not explain the bleeding risk encountered in a larger proportion of hemophilia A carriers with random XCI and borderline/normal FVIII.

Gene Therapy for Hemophilia: a review on clinical benefit, limitations and remaining issues

In the past decade enormous progress has been made in the development of gene therapy for hemophilia A and B. After the first encouraging results of intravenously administered AAV-based liver-directed gene therapy in patients with severe hemophilia B were reported in 2011, many gene therapy studies have been initiated. Most of these studies, using AAV vectors with various gene constructs, showed sufficient FVIII and FIX expression in patients to significantly reduce the number of bleeds and the need for prophylaxis in the fast majority of the severe hemophilia patients. This resulted in great clinical benefit for nearly all patients. In this review we will summarize the most recent findings of reported and ongoing gene therapy trials. We will highlight the successful outcome of trials with focus on the results of recently reported phase 1 trials and preliminary results of phase 2b/3 trials for hemophilia A and B. These new reports also reveal the impact of side effects and drawbacks associated with gene therapy. We will therefore also discuss the limitations and remaining issues of the current gene therapy approaches. These issues have to be resolved before gene therapy will be widely available for the hemophilia patient population.

Management of children with hemophilia A: How emicizumab has changed the landscape

The key to having a good quality of life for an adult with hemophilia rests largely on how he or she was managed as children. With effective prophylaxis, young men can begin their adult life with excellent joint function and few, if any, other sequelae from their disease. Unfortunately, this outcome is not always (nor often) attained because of the limitations of the mainstay of treatment, which is factor replacement therapy. In resource-rich countries with an adequate supply of factor concentrates, the treatment burden and formation of inhibitors limit the potential for an ideal outcome, whereas in much of the world, factor concentrates are too expensive to even be an option. The novel agent, emicizumab, which has become available in numerous countries around the world, is reshaping how one approaches the treatment of children with hemophilia A. This Forum Article, based on a State-of-the-Art lecture given at the 2020 International Society on Thrombosis and Haemostasis Virtual Meeting, presents an approach including clinically applicable algorithms for treating children with hemophilia A in the new era with emicizumab.

The Role of Physiotherapy in the New Treatment Landscape for Haemophilia

The physiotherapist plays an essential role for people with haemophilia, an inherited bleeding disease responsible for musculoskeletal complications. Yet, with the advent of new and advanced therapies, the medical landscape is changing, and physiotherapy must adapt alongside. This paper considers whether there will still be a need for physiotherapy in the era of advanced therapies, and discusses ways in which services should evolve to complement emerging treatment paradigms for haemostasis in people with haemophilia. Ultimately, physiotherapy will remain an important element of care, even for people with little joint damage and low risks in the era of the new mild phenotype. However, competencies will need to evolve, and physiotherapists in both primary care and specialist treatment centres should work with haematology colleagues to develop more sensitive tools for detecting early joint changes. Physiotherapists will also play a crucial role in counselling and physically coaching, monitoring the musculoskeletal status of people with haemophilia who have transitioned to new treatments.

Quantitative measurements of haemophilic joint tissues by point-of-care musculoskeletal ultrasound: Associations with clinical and functional joint outcome parameters

Background

Painful arthropathy is a long‐term complication in patients with hemophilia (PWH), affecting mobility and quality of life. A major barrier for the appraisal of joint health is the absence of point‐of‐care (POC) imaging modalities to promptly identify and manage arthropathic changes. Accordingly, we developed the Joint tissue Activity and Damage Exam (JADE) POC musculoskeletal ultrasound (MSKUS) protocol. JADE is validated for haemophilic joint tissue recognition with high intra/inter‐rater and inter‐operator reliability.

Aims

Evaluate associations of JADE with clinical (Hemophilia Joint Health Score, [HJHS]) and functional (total arc [combined flexion and extension range of motion [ROM]]) parameters.

Methodology

In this multi‐centre prospective study, we recruited PWH A or B with at least one arthropathic joint. We evaluated joint health (both elbows, knees, and ankles) by comparing JADE measurements (soft tissue and cartilage thickness, and osteochondral alterations) with HJHS and total arc.

Results

Of 44 PWH, most had hemophilia A (35/44), were severe (36/44) and had a median age of 36 years. Increasing HJHSs and declining total arc, indicating worsening arthropathy, were associated with JADE measurements in the expected direction, including (1) increasing length of osteochondral alterations, (2) diminished cartilage thickness, and (3) greater soft tissue expansion. The ankles had the highest proportion of joints without measurable (missing) cartilage. In multivariable models MSKUS measurements explained 68% and 71% of the variation in HJHS and total arc respectively for the elbow, 55% and 29% respectively for the knee, and 50% and 73% for the ankle.

Conclusions

This study highlights the associations of direct intra‐articular ultrasonography measurements using the JADE protocol with clinical and functional parameters. Our findings underscore the clinical value of POC MSKUS using the JADE protocol as a complementary instrument for the diagnosis and management of haemophilic arthropathy.

Annual incidence and severity of acute episodes in hereditary thrombotic thrombocytopenic purpura

Hereditary thrombotic thrombocytopenic purpura (hTTP) is a rare thrombotic microangiopathy characterized by severe congenital ADAMTS13 deficiency and recurring acute episodes causing morbidity and premature death. Information on the annual incidence and severity of acute episodes in patients with hTTP is largely lacking. This study reports prospective data on 87 patients from the Hereditary TTP Registry (clinicaltrials.gov #NCT01257269) for survival, frequency, and severity of acute episodes from enrollment until December 2019. The 87 patients, followed up for a median of 4.2 years (range, 0.01-15 years), had a median age at overt disease onset and at clinical diagnosis of 4.6 years and 18 years (range, 0.0-70 years for both), respectively. Forty-three patients received regular plasma prophylaxis, whereas 22 did not, and treatment changed over time or was unknown in the remaining 22. Forty-three patients experienced 131 acute episodes, of which 91 (69%) occurred in patients receiving regular prophylaxis. This resulted in an annual incidence of acute episodes of 0.36 (95% confidence interval [CI], 0.29-0.44) with regular plasma treatment and of 0.41 (95% CI, 0.30-0.56) without regular plasma treatment. More than one-third of acute episodes (n = 51) were documented in children <10 years of age at enrollment and were often triggered by infections. Their annual incidence of acute episodes was significantly higher than in patients aged >40 years (1.18 [95% CI, 0.88-1.55] vs 0.14 [95% CI, 0.08-0.23]). The prophylactic plasma infusion regimens used were insufficient to prevent acute episodes in many patients. Such regimens are burdensome, and caregivers, patients, and their guardians are reluctant to start regular plasma infusions, from which children particularly would benefit.

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.

Bispecific antibodies for the treatment of hemophilia A

INTRODUCTION

Emicizumab is a bispecific antibody exerting cofactor function of FVIIIa irrespective of the presence of FVIII inhibitors. Long-term data of phase 1/2 and phase 3 studies have been accumulated. Various questions such as indicated patients, ITI, application to PUPs, hemostatic treatment including surgeries, and emicizumab-related morbidity remain to be solved.

AREAS COVERED

The review describes the mode of action, data from pre-/post-marketing and ongoing clinical studies according to PubMed search and our own works.

EXPERT OPINION

For patients with a persistent inhibitor, emicizumab is a definite therapeutic option, although the possibility of BPAs-associated thromboembolic/TMA events raises concerns. The use of ITI together with emicizumab prophylaxis is being examined in clinical trials. For non-inhibitor, especially pediatric patients, emicizumab prophylaxis can be an option. Outcome assessment 'beyond ABR' such as joint health, physical/mental activity, QOL is required. Furthermore, continuous data collection for emicizumab-related adverse events and morbidity would be recommended.

Recombinant factor VIII Fc for the treatment of haemophilia A

Prophylaxis with factor VIII (FVIII) is the current therapeutic approach for people with haemophilia A. However, standard half-life (SHL) FVIII products must be injected frequently, imposing a substantial burden on the individual and making it difficult to tailor therapy according to patient need and lifestyle, which could impact adherence. Recombinant FVIII Fc fusion protein (rFVIIIFc; Elocta® , Sobi; Eloctate® , Sanofi) is a recombinant fusion protein that undergoes slower clearance from the body than SHL FVIII products. This pharmacokinetic property of rFVIIIFc allows prophylactic administration every 3-5 days, or once weekly in selected patients, with doses adjusted to patient needs and clinical outcomes. Higher FVIII levels can be achieved maintaining dosing frequency similar to that usually applied with SHL FVIII. This review provides a summary of recent data from the A-LONG, Kids A-LONG, ASPIRE and PUPs A-LONG studies and recently published real-world experience relevant to rFVIIIFc use in individualised regimens. The review also introduces ongoing studies of rFVIIIFc, including its use for induction of immune tolerance, and discusses some aspects to consider when switching patients to rFVIIIFc and managing ongoing treatment. In summary, rFVIIIFc is suitable for individualised prophylaxis regimens that can be tailored according to patient clinical needs and lifestyle.

Patterns of joint damage in severe haemophilia A treated with prophylaxis

OBJECTIVE

The primary objective of this study was to assess whether there are different patterns (classes) of joint health in young boys with severe haemophilia A (SHA) prescribed primary tailored prophylaxis. We also assessed whether age at first index joint bleed, blood group, FVIII gene abnormality variant, factor VIII trough level, first-year bleeding rate and adherence to the prescribed prophylaxis regimen significantly predicted joint damage trajectory, and thus class membership.

METHODS

Using data collected prospectively as part of the Canadian Hemophilia Primary Prophylaxis Study (CHPS), we implemented a latent class growth mixture model technique to determine how many joint damage classes existed within the cohort. We used a multinomial logistic regression to predict the odds of class membership based on the above predictors. We fitted a survival model to assess whether there were differences in the rate of dose escalation across the groups.

RESULTS

We identified three distinct classes of trajectory: persistently low, moderately increasing and rapidly increasing joint scores. By multinomial regression, we found that only age at first index joint bleed predicted rapidly increasing joint scores. The rapidly increasing joint score class group moved through dose escalation significantly faster than the other two groups.

CONCLUSIONS

Using tailored prophylaxis, boys with SHA follow one of three joint health trajectories. By using knowledge of disease trajectories, clinicians may be able to adjust treatment according to a subject's predicted long-term joint health and institute cost-effective programmes of prophylaxis targeted at the individual subject level.

Clinical and ultrasound evaluation of patients with haemophilia on prophylaxis

INTRODUCTION

Primary prophylaxis is the current gold standard in haemophilia care for the prevention of bleeding and ensuing joint damage. Early detection of joint bleeding, whether symptomatic or subclinical, preferably during childhood, helps prevent joint deterioration and subsequent disability. The aim of this study is to evaluate the level of agreement between the Haemophilia Joint Health Score and the Haemophilia Early Arthropathy Detection with Ultrasound tools in children with severe haemophilia on primary and secondary prophylaxis.

MATERIALS AND METHODS

All patients were followed up regularly at our centre. Elbows, knees and ankles were evaluated by physical examination using the Haemophilia Joint Health Score 2.1 (HJHS 2.1), and by ultrasound with HEAD-US score.

RESULTS

A total of 80 children with haemophilia on prophylaxis were included in this study. Mean age was 10.8 years (range 4-18). We evaluated 480 joints, of which 423 (88.1%) were concordant with both tools, whereas 57 (11.9%) were discordant; 377 (78.5%) joints scored 0 on HJHS, 370 (77%) on HEAD-US and 345 (72%) on both tools. The overall Kappa concordance coefficient was .656. For elbows, knees and ankles the respective values were .783, .522 and .589. For HJHS scores greater than 3, all joints scored ≥1 on HEAD-US.

CONCLUSION

HJHS and HEAD-US are used to assess joint health in children with haemophilia on prophylaxis. In this study, the level of agreement between both tools was consistent with literature values only for the elbow joint.

Personalised Prophylaxis in a Child with Haemophilia A and Type 1 Diabetes

Poor management of either type 1 diabetes or haemophilia A can lead to complications such as organ dysfunction and haemarthropathy. Here, we describe the case of an 8-year-old boy diagnosed with severe haemophilia A shortly after birth. At 2 years old, he was also diagnosed with type 1 diabetes. After six years, the haemophilia treatment was changed from a plasma-derived factor VIII (FVIII) concentrate (octanate^®, Octapharma, Lachen, Switzerland) to Nuwiq^® (simocotocog alfa, Octapharma, Lachen, Switzerland), a recombinant FVIII (rFVIII) product from a human cell line, which allowed for a personalised treatment schedule that supported good adherence. The dosing regimen could be reduced to two weekly rFVIII infusions. The patient has experienced no spontaneous bleeds since switching to rFVIII and shows no signs of joint damage after over seven years of FVIII prophylaxis. rFVIII was well tolerated, with no treatment-related adverse events observed. This case illustrates the importance of treatment personalisation for young patients and their families managing concomitant diseases.

Expert opinion on the UK standard of care for haemophilia patients with inhibitors: a modified Delphi consensus study

Background and Aims:

Despite advances in haemophilia care, inhibitor development remains a significant complication. Although viable treatment options exist, there is some divergence of opinion in the appropriate standard approach to care and goals of treatment. The aim of this study was to assess consensus on United Kingdom (UK) standard of care for child and adult haemophilia patients with inhibitors.

Methods:

A modified Delphi study was conducted using a two-round online survey. A haemophilia expert steering committee and published literature informed the Round 1 questionnaire. Invited participants included haematologists, haemophilia nurses and physiotherapists who had treated at least one haemophilia patient with inhibitors in the past 5 years. Consensus for 6-point Likert scale questions was pre-defined as ⩾70% participants selecting 1–2 (disagreement) or 5–6 (agreement).

Results:

In all, 46.7% and 35.9% questions achieved consensus in Rounds 1 (n = 41) and 2 (n = 34), respectively. Consensus was reached on the importance of improving quality of life (QoL) and reaching clinical goals such as bleed prevention, eradication of inhibitors and pain management. There was agreement on criteria constituting adequate/inadequate responses to immune tolerance induction (ITI) and the appropriate factor VIII dose to address suboptimal ITI response. Opinions varied on treatment aims for adults and children/adolescents, when to offer prophylaxis with bypassing agents and expectations of prophylaxis. Consensus was also lacking on appropriate treatment for mild/moderate patients with inhibitors.

Conclusion:

UK healthcare professionals appear to be aligned on the clinical goals and role of ITI when managing haemophilia patients with inhibitors, although novel treatment developments may require reassessment of these goals. Lack of consensus on prophylaxis with bypassing agents and management of mild/moderate cases identifies a need for further research to establish more comprehensive, evidence-based treatment guidance, particularly for those patients who are unable/prefer not to receive non-factor therapies.

Population Pharmacokinetic Analysis of Recombinant Factor VIII Fc Fusion Protein in Subjects With Severe Hemophilia A: Expanded to Include Pediatric Subjects

Recombinant factor VIII Fc fusion protein (rFVIIIFc) has been indicated for adults and children with hemophilia A. The objective of this article was to build a population pharmacokinetic (PK) model using adult and pediatric data sets and explore relevant dosing scenarios across all ages. The activity-time profiles of rFVIIIFc from 3 clinical studies (all trials registered at https://www.clinicaltrials.gov: NCT01027377, NCT01181128, and NCT01458106) were characterized, and covariates that determine variability of rFVIIIFc PK in children and adults were identified and implemented. Data sets were pooled to estimate population PK parameters. Simulations were conducted to generate activity-time profiles at steady state (SS). The proportion of subjects maintaining SS trough >1 and >3 IU/dL and time >10 IU/dL were estimated. The rFVIIIFc model was a two-compartment model that identified weight and von Willebrand factor as significant covariates. Model-predicted SS peaks and troughs of rFVIIIFc activity-time profiles confirmed the necessity of modifying dosing in pediatric subjects. The model also predicted that the average subject in the adult and adolescent group dosed with 40 IU/kg every 2 days maintained factor VIII activity >10 IU/dL for the entire duration. Children aged <6 years and aged 6 to <12 years receiving this dose maintained factor VIII activity of >10 IU/dL for nearly two-thirds and three-quarters of their time, respectively. In conclusion, these population PK analyses characterize activity-time profiles for rFVIIIFc among pediatric and adult subjects. The model was used for simulation of clinically relevant dosing scenarios, which can provide better protection and better clinical outcomes.

Correlation between Hemophilia Early Arthropathy Detection with Ultrasound (HEAD-US) score and Hemophilia Joint Health Score (HJHS) in patients with hemophilic arthropathy

BACKGROUND

Hemophilic arthropathy, a condition manifested as joint destruction due to spontaneous joint bleeding, is one complication of hemophiliac patients. Early detection and intervention may improve the outcome, in which ultrasonography can be an ideal modality with the introduction of HEAD-US (Hemophilia Early Arthropathy Detection with Ultrasound) protocol. Studies have shown US benefit in hemophiliac patients, including its potential as an alternative for the Hemophiliac Joint Health Score (HJHS) system. However, many of the studies were conducted in countries with better management of hemophilia using prophylaxis treatment. It is unclear whether HEAD-US has a correlation with HJHS in countries using episodic treatment only, like in Indonesia.

PURPOSE

This study aimed to explore the correlation between HEAD-US and HJHS in hemophiliac patients with joint problems in Indonesia.

MATERIALS AND METHODS

A cross-sectional correlation study between HEAD-US and HJHS was performed with primary data collected from 120 hemophilic patients. US examination was performed on elbow, knee and ankle joints using the HEAD-US scoring method by a musculoskeletal radiologist. HJHS examination was conducted by a trained physiotherapist and a medical rehabilitation specialist. All examiner is member of multidisciplinary Hemophiliac Management Team in Cipto Mangunkusumo General Hospital in Jakarta, Indonesia.

RESULTS

The mean age of the participant was 9.3 (5-14) years old. The median score of HEAD-US was 8 (1-28) with most of the joint abnormalities found on the ankles. The median score of HJHS was 3 (0-35), with most joint abnormalities found on the knees. There was a moderate correlation between HEAD-US and HJHS score (p < 0.05, r = 0.65).

CONCLUSION

HEAD-US shows a moderate correlation to HJHS in hemophiliac patients who received episodic treatment. HEAD-US can provide additional value in the anatomical evaluation of the joint and could be complementary to HJHS in assessing the joint status in hemophilic patient.

A Preconditioning Strategy to Augment Retention and Engraftment Rate of Donor Cells During Hepatocyte Transplantation

BACKGROUND

Hepatocyte transplantation has been extensively investigated as an alternative to orthotopic liver transplantation. However, its application in routine clinical practice has been restricted because of low initial engraftment and subsequent repopulation.

METHODS

Using mice as a model, we have developed a minimally invasive and nontoxic preconditioning strategy based on preadministration of antibodies against hepsin to increase donor hepatocyte retention and engraftment rate.

RESULTS

Liver sinusoid diameters decreased significantly with antihepsin pretreatment, and graft cell numbers increased nearly 2-fold in the recipients' liver parenchyma for 20 days after hepatocyte transplantation. Postoperative complications such as hepatic ischemia injury or apparent immune cell accumulation were not observed in recipients. In a hemophilia B mouse model, antihepsin preconditioning enhanced the expression and clotting activity of coagulation factor IX (FIX) to nearly 2-fold that of immunoglobulin G-treated controls and maintained higher plasma FIX clotting activity relative to the prophylactic range for 50 days after hepatocyte transplantation. Antihepsin pretreatment combined with adeno-associated virus-transduced donor hepatocytes expressing human FIX-Triple, a hyperfunctional FIX variant, resulted in plasma FIX levels similar to those associated with mild hemophilia, which protected hemophilia B mice from major bleeding episodes for 50 days after transplantation. Furthermore, antihepsin pretreatment and repeated transplantation resulted in extending the therapeutic period by 30 days relative to the immunoglobulin G control.

CONCLUSIONS

Thus, this antihepsin strategy improved the therapeutic effect of hepatocyte transplantation in mice with tremendous safety and minimal invasion. Taken together, we suggest that preconditioning with antihepsin may have clinical applications for liver cell therapy.

Current and Future Options of Haemophilia A Treatments

Introduction: The standard treatment of hemophilia A consists of the prophylactic administration of a coagulation factor concentrate, to be administered intravenously several times a week. Newly approved factor concentrates and non-factor products reduce the frequency of injection and offer better protection against bleeding.Areas covered: New treatment options for hemophilia A are either coagulation factor concentrates based on innovative active principles extending half-life (EHL) or non-factor products allowing subcutaneous application with an extended half-life, so that their broader application only needs to be made every one to four weeks. Other new therapeutic options are still in clinical studies, such as the inhibition of TFPI (tissue factor pathway inhibitor) or small interfering mRNA molecule against antithrombin and gene therapy for hemophilia A.Expert opinion: It can be expected that patients with hemophilia will benefit significantly from the new treatment options and that the protection against bleeding and joint damage as well as the quality of life will increase. The availability of alternatives to classical replacement therapy will require the development of treatment algorithms for patients with hemophilia. It is still unclear to what extent factor substitution will be challenged by the new therapies as first-line therapy.

Haemophilia, state of the art and new therapeutic opportunities, a regulatory perspective

Haemophilia A and B are rare bleeding disorders. Over the past decades, they have been transformed from debilitating diseases to manageable conditions in the Western world. However, optimizing haemophilia care remains challenging in developing countries. Several challenges and unmet needs remain in the treatment of the haemophilia limiting the QoL of patients. These challenges are now being addressed by extended half‐life recombinant factors, rebalancing and substitution therapies. Gene therapy and genome editing show promise for a definite clinical cure. Here, we provide an overview of new therapeutic opportunities for haemophilia and their advances and limitations from a regulatory perspective. The database on human medicines from the European Medicines Agency (EMA) was used and data from rare disease (orphan) designations and EPARs were retrieved for the analysis. Clinical trial databases were used to query all active studies on haemophilia. Gene therapy medicinal products based on AAV and lentiviral vectors are in development and clinical trials have reported substantial success in ameliorating bleeding tendency in haemophilia patients. The prospect of gene editing for correction of the underlying mutation is on the horizon and has considerable potential. With regard to the benefit of the gene therapy medicinal products, more long‐term efficacy and safety data are awaited. We are entering an era of innovation and abundance in treatment options for those affected by bleeding disorders, but issues remain about the affordability and accessibility to patients.

Red Blood Cells are Appropriate Carrier for Coagulation Factor VIII

AIMS

Factor VIII (FVIII) replacement therapy remains a primary treatment for hemophilia A, however, the development of FVIII antibodies (inhibitors) and short half-life of the FVIII products are the major complications. Erythrocytes may prevent rapid removal of drugs from plasma. Erythrocytes are biocompatible and non-immunogenic drug delivery. In this study, in vitro activity of FVIII encapsulated by human erythrocytes was investigated.

METHODS

FVIII was loaded into erythrocytes using the hypo-osmotic dialysis technique. FVIII activity assay has been analyzed using Activated Partial Thromboplastin Time (APTT). Presence of FVIII on erythrocytes was detected by western blotting and flowcytometry using specific monoclonal antibody (abcam, U.K) against FVIII. Moreover, the osmotic fragility and hematologic parameters of FVIII-loaded carrier erythrocytes were measured.

RESULTS

Our results indicated that FVIII could not cross the membrane, where plenty of FVIII was found on the surface of the carrier erythrocyte. Flow cytometery results showed that 11% of the loaded carrier erythrocytes was positive for FVIII protein on their surface. The greatest activation of FVIII in both groups including lysate and non-lysate FVIII-loaded RBCs was observed on the first day, and the coagulant activity of this factor was gradually reduced on days 3 and 5. In 1:50 dilution of both groups, significant differences in FVIII activity were observed in 1:50 dilution of both groups, especially on the 5th day.

CONCLUSION

This study aims to introduce erythrocytes as appropriate carriers for FVIII to prolong the dosing intervals in the effective and safe levels for a relatively longer time.

Safety evaluation of emicizumab prophylaxis in individuals with haemophilia A

INTRODUCTION

Emicizumab is a bispecific-humanized monoclonal antibody that improves hemostasis by bridging activated factor IX and factor X to substitute for the function of missing activated FVIII. It is an alternative to prophylaxis with factor VIII replacement and is associated with improved outcomes in individuals with hemophilia A with and without inhibitors.

AREAS COVERED

Emicizumab is efficacious in reducing bleeding events when compared to on-demand treatment and factor-based prophylaxis. Except for the few thrombotic microangiopathy and thrombotic event cases mainly seen in the HAVEN 1 trial, emicizumab has an overall excellent safety profile with minimal side effects.

EXPERT OPINION

Knowledge gaps include the efficacy and safety of emicizumab in younger age groups and those with mild or moderate hemophilia A. Future directions for research include exploring the risk of inhibitor recurrence in patients with a history of high titer inhibitor who have been successfully tolerized, who switch from factor prophylaxis to emicizumab, as well as conducting 'real world studies' to evaluate the patient's perception of emicizumab in regard to ease and tolerability in order to optimize individualized treatment plans.

EPCR deficiency or function-blocking antibody protects against joint bleeding-induced pathology in hemophilia mice

We recently showed that clotting factor VIIa (FVIIa) binding to endothelial cell protein C receptor (EPCR) induces anti-inflammatory signaling and protects vascular barrier integrity. Inflammation and vascular permeability are thought to be major contributors to the development of hemophilic arthropathy following hemarthrosis. The present study was designed to investigate the potential influence of FVIIa interaction with EPCR in the pathogenesis of hemophilic arthropathy and its treatment with recombinant FVIIa (rFVIIa). For this, we first generated hemophilia A (FVIII-/-) mice lacking EPCR (EPCR-/-FVIII-/-) or overexpressing EPCR (EPCR++ FVIII-/-). Joint bleeding was induced in FVIII-/-, EPCR-/-FVIII-/-, and EPCR++FVIII-/- mice by needle puncture injury. Hemophilic synovitis was evaluated by monitoring joint bleeding, change in joint diameter, and histopathological analysis of joint tissue sections. EPCR deficiency in FVIII-/- mice significantly reduced the severity of hemophilic synovitis. EPCR deficiency attenuated the elaboration of interleukin-6, infiltration of macrophages, and neoangiogenesis in the synovium following hemarthrosis. A single dose of rFVIIa was sufficient to fully prevent the development of milder hemophilic synovitis in EPCR-/-FVIII-/- mice. The development of hemophilic arthropathy in EPCR-overexpressing FVIII-/- mice did not significantly differ from that of FVIII-/- mice, and 3 doses of rFVIIa partly protected against hemophilic synovitis in these mice. Consistent with the data that EPCR deficiency protects against developing hemophilic arthropathy, administration of a single dose of EPCR-blocking monoclonal antibodies markedly reduced hemophilic synovitis in FVIII-/- mice subjected to joint bleeding. The present data indicate that EPCR could be an attractive new target to prevent joint damage in hemophilia patients.

The changing treatment landscape in haemophilia: from standard half-life clotting factor concentrates to gene editing

Congenital haemophilia A (factor VIII deficiency) and B (factor IX deficiency) are X-linked bleeding disorders. Replacement therapy has been the cornerstone of the management of haemophilia, aiming to reduce the mortality and morbidity of chronic crippling arthropathy. Frequent intravenous injections are burdensome and costly for patients, consequently with poor adherence and restricted access to therapy for many patients worldwide. Bioengineered clotting factors with enhanced pharmacokinetic profiles can reduce the burden of treatment. However, replacement therapy is associated with a risk for inhibitor development that adversely affects bleeding prevention and outcomes. Novel molecules that are subcutaneously delivered provide effective prophylaxis in the presence or absence of inhibitors, either substituting for the procoagulant function of clotting factors (eg, emicizumab) or targeting the natural inhibitors of coagulation (ie, antithrombin, tissue factor pathway inhibitor, or activated protein C). The ultimate goal of haemophilia treatment would be a phenotypical cure achievable with gene therapy, currently under late phase clinical investigation.

Functional and joint evaluation in a prospective cohort of patients with severe haemophilia

INTRODUCTION

Arthropathy is the main morbidity of haemophilia. Periodic joint health assessment enables a better understanding of the limitations of these patients.

OBJECTIVE

To evaluate the functional and joint performance in patients with haemophilia at one-year follow-up, as well as its association with prophylactic treatment and attendance at scheduled consultations at a haemophilia treatment centre.

METHODS

This prospective cohort study included patients with severe haemophilia aged 7 years or more and treated at Fundação Hemocentro de Brasília, Brazil, from January 2014 to December 2018. The Hemophilia Joint Health Score and Functional Independence Score in Hemophilia were assessed at the first consultation and after a one-year follow-up.

RESULTS

The study included 69 patients. The mean age at study recruitment was 22.5 ± 4.5 years, 62.3% of patients aged 18 years or older, and 29 patients were receiving primary prophylaxis (38.0%). There was a positive correlation between HJHS and age and a negative correlation between FISH and age. The worsening HJHS was associated with non-primary prophylaxis and non-attendance at scheduled multidisciplinary consultations. The worsening FISH was associated with non-primary prophylaxis. The correlation between FISH and treatment adherence was significant for the delta.

CONCLUSION

The older the patient with haemophilia, the higher the probability of a worsening of the HJHS. In the presence of more arthropathies, the older the patient, the worse the FISH. Patients receiving primary prophylaxis show better results in the HJHS and FISH when compared to patients receiving secondary prophylaxis and/or on-demand treatment.

Redefining prophylaxis in the modern era

Prophylaxis is the globally accepted standard of care for persons with haemophilia and presents many advantages over episodic treatment. The prophylaxis benefits include bleed reduction, reduction in musculoskeletal complications and improvement in the quality of life. The currently evolving novel therapies for the management of haemophilia has ushered a new era characterized by improved prophylaxis targets and outcomes. These redefined targets and outcomes have necessitated the need to also redefine prophylaxis. In this state-of-the-art review, we redefine prophylaxis in the modern era by revisiting its definition, presenting data to support higher trough levels to achieve with prophylaxis and introducing steady-state haemostasis as a possible new target for prophylaxis.