How much prophylaxis is enough in haemophilia?

INTRODUCTION

Prophylaxis has become standard of care for all persons with haemophilia (PWH) with a severe phenotype. However, 'standard prophylaxis' with either factor or non-factor therapies (currently only emicizumab available) is prohibitively expensive for much of the world. We sought to address the question of 'How much prophylaxis is enough?' and 'Can it be individualized?' and specifically 'Can emicizumab be individualized?'.

METHODS

We reviewed the literature on prophylaxis in haemophilia since its inception in the 1950s to the present, the development of more and less intense factor prophylaxis regimens and their outcomes and additionally the published outcomes of prophylaxis with low dose emicizumab.

RESULTS

What these experiences collectively show is that low dose emicizumab does result in significant benefits to patients whilst being much less expensive than a "one size fits all" emicizumab prophylaxis approach. We also took note that some non-factor therapies still in development are individualized given that high doses of these can potentially put patients at risk.

CONCLUSIONS

Prophylaxis is now clearly accepted as standard of care for PWH with a severe phenotype but now in a very short time a large assortment of different treatment options for prophylaxis have become/are becoming available and the haemophilia community will need to determine how to best use these recognizing that no 'one treatment fits all'.

Adherence tool for prophylactic haemophilia treatment in adult and adolescent patients: A systematic review and meta-analysis protocol

Hemophilia is a congenital bleeding disorder resulting from a low level or deficiency of clotting factors. It is an x-linked recessive disease and happens almost exclusively in males whereas females are the carrier of the affected gene. The most common types of hemophilia are hemophilia A and Hemophilia B. Hemophilia is classified into mild, moderate and severe. Prophylaxis treatment has more advantages clinically compare to on-demand therapy. It may reduce the bleeding frequency, gives protection from joint damage, may lower the number of total bleeding episodes per year, and may reduce annualised spontaneous and trauma related bleeding events. However, prophylaxis treatment needs regular weekly infusions therefore it is painful to administer especially if the vein is difficult to access. It may cause pain at the site of injections and may lead to non-adherence to treatment. Non-adherence to a regimen will result in insufficient clotting factor levels in the body. The efficacy of the medication is reduced and may lead to a high bleeding tendency. Thus far, the study on adult haemophilic patient adherence tool is scarce and limited; and therefore this review is warranted. The study protocol is conducted as per the PRISMA-P guideline. There are 4 concepts in this systematic review which are Haemophilia, adult and adolescence, preventive treatment and adherence. Articles will be sought from electronic databases PUBMED, Ovid EMBASE, CINAHL, and SCOPUS using the MeSH term, synonym free-text word, truncation, and proximity operators as per each database. The proposed keywords within each concept will be joined using the Boolean operator "OR "and the 4 different concepts combined using the Boolean operator "AND". Search will be limited to Human, English language, and publication until 2022. Studies will be included if they meet the study inclusion criteria. The quality of the studies will be appraised using the Newcastle-Ottawa quality assessment scale (NOS) for observation-based studies. This systematic review does not require formal ethical approval as data will be extracted from selected published studies. The results will be disseminated through a peer-reviewed publication and relevant conference presentations.(PROSPERO registration CRD42021273813).

Multiyear Factor VIII Expression after AAV Gene Transfer for Hemophilia A

BACKGROUND

The goal of gene therapy for patients with hemophilia A is to safely impart long-term stable factor VIII expression that predictably ameliorates bleeding with the use of the lowest possible vector dose.

METHODS

In this phase 1-2 trial, we infused an investigational adeno-associated viral (AAV) vector (SPK-8011) for hepatocyte expression of factor VIII in 18 men with hemophilia A. Four dose cohorts were enrolled; the lowest-dose cohort received a dose of 5  × 10¹¹ vector genomes (vg) per kilogram of body weight, and the highest-dose cohort received 2 × 10¹² vg per kilogram. Some participants received glucocorticoids within 52 weeks after vector administration either to prevent or to treat a presumed AAV capsid immune response. Trial objectives included evaluation of the safety and preliminary efficacy of SPK-8011 and of the expression and durability of factor VIII.

RESULTS

The median safety observation period was 36.6 months (range, 5.5 to 50.3). A total of 33 treatment-related adverse events occurred in 8 participants; 17 events were vector-related, including 1 serious adverse event, and 16 were glucocorticoid-related. Two participants lost all factor VIII expression because of an anti-AAV capsid cellular immune response that was not sensitive to immune suppression. In the remaining 16 participants, factor VIII expression was maintained; 12 of these participants were followed for more than 2 years, and a one-stage factor VIII assay showed no apparent decrease in factor VIII activity over time (mean [±SD] factor VIII activity, 12.9±6.9% of the normal value at 26 to 52 weeks when the participants were not receiving glucocorticoids vs. 12.0±7.1% of the normal value at >52 weeks after vector administration; 95% confidence interval [CI], -2.4 to 0.6 for the difference between matched pairs). The participants had a 91.5% reduction (95% CI, 88.8 to 94.1) in the annualized bleeding rate (median rate, 8.5 events per year [range, 0 to 43.0] before vector administration vs. 0.3 events per year [range, 0 to 6.5] after vector administration).

CONCLUSIONS

Sustained factor VIII expression in 16 of 18 participants who received SPK-8011 permitted discontinuation of prophylaxis and a reduction in bleeding episodes. No major safety concerns were reported. (Funded by Spark Therapeutics and the National Heart, Lung, and Blood Institute; ClinicalTrials.gov numbers, NCT03003533 and NCT03432520.).

Depressive symptoms and adherence to prophylaxis in patients with haemophilia from Croatia and Slovenia

INTRODUCTION

Adherence to a prophylactic therapy is obligatory to prevent bleeding in patients with haemophilia. It has already been recognized that depression is associated with treatment adherence.

AIM

The aim of this study was to examine the prevalence of depressive symptoms in adults with haemophilia using an instrument designed or validated for diagnosing or screening for depression and to investigate the association of symptoms of depression with nonadherence to prophylactic therapy in patients from two East European countries.

METHODS

Adult patients with severe or moderate haemophilia receiving prophylaxis were eligible for the study. Depressive symptoms were assessed with BDI-II, adherence with VERITAS-Pro, demographic and socioeconomic data were collected using a questionnaire, and clinical data were obtained from medical records.

RESULTS

Final sample included 81 participants (median age was 45 years, range 18-73 years). There were 9 (11%) participants with scores on BDI-II above 14 points, the cut-off score for depressive symptomatology. In general, participants were adherent. However, there were 14 (17%) participants who had scores above 57 points, the cut-off score for nonadherence. There was an association between having depressive symptoms and being nonadherent, and depressive symptoms explained additional variance in adherence after controlling for sociodemographic, psychosocial and clinical characteristics.

CONCLUSION

Since there is an association between depressive symptoms and nonadherence, it would be beneficial for both patients and the public health system for screening for depressive symptoms to be included as a part of the treatment protocol.

Hemophilia - Impact of Recent Advances on Management

There have been numerous advances in the field of hemophilia management in the past decade, including long acting factor products, non-factor products, and potentially curative interventions such as gene therapy. Each of these interventions introduces exciting treatment modalities to patients with both hemophilia A and B, however they also pose a daunting array of possible management options. Adverse reactions to novel agents are being reported as more patients are treated and long-term sustainability of interventions such as gene therapy is yet to be determined. The practicing hematologist should be aware of the intricacies involved in customizing care for their individual patients and be aware of the monitoring strategies for each interventional strategy to avoid adverse events. Upfront cost vs. long term benefit should be considered as choices of treatment strategies are made, especially in resource poor countries. The goal of the newer agents is to decrease annualized bleed rates and avoid debilitating arthropathy. This article looks at current treatment models for prophylaxis and management of inhibitors, reviews the recent advances in the field (with bioengineered factor products, non-factor products and gene therapy) and summarizes the incorporation of these new interventions in the treatment plan for patients with hemophilia.

Low Dose Prophylaxis vis-a-vis on-Demand Treatment Strategies for Hemophilia: A Cost Effective and Disability Attenuating Approach

AIM

To assess effect of low dose prophylaxis in hemophilics in terms of bleeding, joint function, QoL and cost-effectiveness.

METHODS

Analytic study done during one year among 70 adult hemophilics. In observation period (12 weeks), on-demand factor and during prophylaxis (12 weeks), low dose factor was given (Factor VIII 10 IU/KgBW biweekly for haemophilia A and Factor IX 20 IU/KgBW weekly for haemophilia B). Clinical joint assessment was done by Gilbert score and improvement by WFH definitions.

RESULTS

Bleed reduced by 68.99% in moderate hemophilics (40 v/s 129) and 64.86% in severe hemophilics (26 v/s74) (p<0.05). During observation in moderate hemophilics, joint, soft tissue and mucosal bleeds occurred in frequency of 120, 1 and 8. This was reduced to 39 joint bleeds, 1 soft tissue bleed and no mucosal bleed during prophylaxis. In severe hemophilics, 70 joint, 2 soft tissue bleeds and 2 mucosal bleeds occurred during observation which reduced to 26 joint bleeds without soft tissue/mucosal bleed in prophylaxis. Bleeding episodes decreased by 65.79% in joints, 66.67% in soft tissues, 100% mucosal bleeds. After prophylaxis one joints (0.61 %) showed good improvement in joint function, thirty (18.18 %) joints showed moderate improvement and ninety two joints (55.76 %) showed mild improvement in joint function. Hospitalization reduced by 60.34% (163 v/s 411) and absenteeism by 53.73% (279 v/s 603). Factors consumption reduced by 12.33 % during prophylaxis period.

CONCLUSION

The low dose prophylaxis strategy significantly decreased the subsequent episodes of total bleeds including joint bleeds and improved the joint function as well as quality of life.

Prevention and Management of Bleeding Episodes in Children with Hemophilia

Regular prophylactic treatment with factor VIII (FVIII) and factor IX (FIX) concentrates in hemophilia A and B, respectively, is introduced in early infancy and has resulted in dramatic improvement of the conditions. Recombinant FVIII and FIX concentrates have been available for > 25 years and have been modified and refined through the years; however, unfortunately frequent intravenous administrations are still necessary. The half-lives of these products have now been extended (EHL) by fusion with albumin, the Fc-portion of IgG, or by being PEGylated. This has been very successful for EHL-FIX, with 3-5 times longer half-life, and to a lesser degree for EHL-FVIII with a half-life extension of only 1.5 times the conventional products. New treatment principles using FVIII mimetics or monoclonal antibodies that rebalance the pro- and anti-coagulation system by interfering with production of anti-thrombin or tissue factor pathway inhibitor have the benefits of long-lasting activity, subcutaneous administration, and being useful in patients both with and without neutralizing antibodies. As the ultimate treatment, recent progress has also been made with gene therapy of both hemophilia A and B.

Optimization of prophylaxis for hemophilia A

Background & aims

Prophylactic injections of factor VIII reduce the incidence of bleeds and slow the development of joint damage in people with hemophilia. The aim of this study was to identify optimal person-specific prophylaxis regimens for children with hemophilia A.

Methods

Analytic and numerical methods were used to identify prophylaxis regimens which maximize the time for which plasma factor VIII concentrations exceed a threshold, maximize the lowest plasma factor VIII concentrations, and minimize risk of bleeds.

Results

It was demonstrated analytically that, for any injection schedule, the regimen that maximizes the lowest factor VIII concentration involves sharing doses between injections so that all of the trough concentrations in a prophylaxis cycle are equal. Numerical methods were used to identify optimal prophylaxis schedules and explore the trade-offs between efficacy and acceptability of different prophylaxis regimens. The prophylaxis regimen which minimizes risk of bleeds depends on the person’s pattern of physical activity and may differ greatly from prophylaxis regimens that optimize pharmacokinetic parameters. Prophylaxis regimens which minimize risk of bleeds also differ from prophylaxis regimens that are typically prescribed. Predictions about which regimen is optimal are sensitive to estimates of the effects on risk of bleeds of factor VIII concentration and physical activity.

Conclusion

The methods described here can be used to identify optimal, person-specific prophylaxis regimens for children with hemophilia A.

Adherence to Prophylaxis in Adolescents and Young Adults with Severe Haemophilia: A Quantitative Study with Patients

INTRODUCTION

haemophilia is an inherited bleeding disorder caused by a deficiency in one of the blood coagulation factors. For people affected by severe haemophilia, the deficiency can cause spontaneous internal bleeding. Most young people with severe haemophilia in the UK follow a preventative treatment regimen (prophylaxis) consisting of several intravenous injections of factor concentrate each week. There is good evidence that prophylaxis reduces bleeds whilst also improving quality of life. However, levels of adherence among young people with haemophilia reported in the existing literature vary widely and are predominately based on estimations made by healthcare professionals and parents. Additionally, drivers of (non)adherence among young people specifically have not been evidenced.

AIM

to assess self-reported adherence among young people with haemophilia, provide evidence of psychosocial predictors of adherence, and to establish the associations between non-adherence and number of bleeds and hospital visits.

METHODS

91 participants were recruited during outpatient appointments in 13 haemophilia centres across England and Wales, and invited to complete a questionnaire assessing self-reported adherence (VERITAS-Pro), Haemophilia-related pain and impact of pain, Illness Perceptions, Beliefs about Medications, Self-efficacy, Outcome expectations, Positive and Negative Affect, and Social support. Number of hospital visits and bleeds during the previous six months were collected from medical files.

RESULTS

Of 78 participants with complete data, just 18% had scores indicating non-adherence. Psychosocial predictors differed between intentional (skipping) and un-intentional (forgetting) non-adherence. Overall, however, better adherence was reported where participants perceived the need for prophylaxis was greater than their concern over taking it as well as having a positive expectancy of its effectiveness, good social support and a stronger emotional reaction to having haemophilia.

CONCLUSION

The findings indicate that adherence is generally good, and that assessing illness and treatment beliefs, social support and outcome expectations may play a valuable role in identifying which individuals are at risk of non-adherence. Interventions aimed at improving adherence should particularly consider improving social support, reducing patients' concerns about prophylaxis, increasing their belief in the necessity of prophylaxis, and increasing positive outcome expectations.

Advances in hemophilia and the role of current and emerging prophylaxis

The primary goal of hemophilia treatment and management is the prevention of painful, disabling, and costly joint arthropathy that results from its characteristic bleeding into joints and muscles. Prophylactic treatment with clotting-factor concentrates has been shown to prevent hemophilic arthropathy and is, therefore, the standard of care for hemophilia A and B. Data has demonstrated the clinical efficacy and overall benefits of prophylaxis in young children, adolescents, and adults. Early initiation with prima-ry prophylaxis is ideal, but secondary prophylaxis in adolescents and adults has also demonstrated significant success. Because the standard of care includes prophylaxis with factor-concentrate replacement in order to prevent joint damage in patients with hemophilia, prophylaxis is now more common and needs to be addressed in all clinical settings, including managed care. However, further research is needed to help clinicians develop individualized factor-replacement protocols and under-stand the impact of long-term use into adulthood. World Federation of Hemophilia guidelines do not have definitive recommendations on continuation of prophylaxis into adulthood. The optimal regimen for initiating prophylaxis, duration of treatment, and dosing regimens continue to be studied.

Economic costs of hemophilia and the impact of prophylactic treatment on patient management

Hemophilia is a rare congenital bleeding disorder characterized by spontaneous and potentially life-threatening bleeding episodes. In addition to its clinical burden on the patient, the condition also places a significant economic burden on healthcare payers, patients/caregivers, and society. Hemophilia is associated with staggering direct costs from hospitalizations, outpatient visits, and drug treatments, as well as high indirect costs from diminished work productivity and absenteeism from work and school. Additionally, hemophilia incurs tremendous intangible costs, including reduced quality of life, pain and suffering, and the emotional and physical toll on the patient and caregivers. The evolution of treatment patterns in hemophilia has transformed the once-fatal disease into a chronic but potentially well-managed condition through the use of prophylaxis treatment. However, other complications, such as development of inhibitory antibodies, have added to the complexity of managing the disease and its costs. To ensure optimal treatment outcomes and disease management, there is a critical need to understand the utilization of healthcare resources in the treatment of hemophilia and to educate patients on the importance of treatment adherence and compliance to reduce long-term effects on musculoskeletal health.

Recombinant factor VIII Fc fusion protein for the prevention and treatment of bleeding in children with severe hemophilia A

BACKGROUND

Prophylactic factor replacement, which prevents hemarthroses and thereby reduces the musculoskeletal disease burden in children with hemophilia A, requires frequent intravenous infusions (three to four times weekly).

OBJECTIVE

Kids A-LONG was a phase 3 open-label study evaluating the safety, efficacy and pharmacokinetics of a longer-acting factor, recombinant factor VIII Fc fusion protein (rFVIIIFc), in previously treated children with severe hemophilia A (endogenous FVIII level of < 1 IU dL(-1) [< 1%]).

METHODS

The study enrolled 71 subjects. The starting rFVIIIFc regimen was twice-weekly prophylaxis (Day 1, 25 IU kg(-1) ; Day 4, 50 IU kg(-1) ); dose (≤ 80 IU kg(-1) ) and dosing interval (≥ 2 days) were adjusted as needed. A subset of subjects had sequential pharmacokinetic evaluations of FVIII and rFVIIIFc. The primary endpoint was development of inhibitors (neutralizing antibodies). Secondary endpoints included pharmacokinetics, annualized bleeding rate (ABR), and number of infusions required to control a bleed.

RESULTS

No subject developed an inhibitor to rFVIIIFc. Adverse events were typical of a pediatric hemophilic population. The rFVIIIFc half-life was prolonged relative to that of FVIII, consistent with observations in adults and adolescents. The median ABR was 1.96 overall, and 0.00 for spontaneous bleeds; 46.4% of subjects reported no bleeding episodes on study. Ninety-three per cent of bleeding episodes were controlled with one to two infusions. The median average weekly rFVIIIFc prophylactic dose was 88.11 IU kg(-1) . At study end, 62 of 69 subjects (90%) were infusing twice weekly. Among subjects who had been previously receiving FVIII prophylaxis, 74% reduced their dosing frequency with rFVIIIFc.

CONCLUSION

Twice-weekly infusions with rFVIIIFc were well tolerated and yielded low bleeding rates in children with severe hemophilia A.

Comparison of two laboratory assays in monitoring the efficacy of different prophylaxis regimens for severe haemophilia

BACKGROUND

The goal of this study was to compare the validity of two laboratory assays, rotation thromboelastometry (ROTEM) and endogenous thrombin potential (ETP), in monitoring and evaluating different prophylactic treatment regimens in patients with severe haemophilia.

METHODS

Twenty adult patients with severe haemophilia were divided into three groups according to treatment regimen with concentrate of factor (F) VIII/IX: full-dose prophylaxis (5 patients), intermediate-dose prophylaxis (5 patients), and on demand treatment (10 patients).

RESULTS

The ROTEM for the group treated with full-dose prophylaxis was significantly lower than ROTEM for the group treated with intermediate-dose prophylaxis (p = 0.025). Among the patients given full-dose prophylaxis, 40% (2 patients) had prolonged ROTEM after 3 months of treatment, while among those given intermediate-dose prophylaxis all patients (100%, 5 patients) had prolonged ROTEM (p = 0.038). The ETP was significantly improved after 3 months of full-dose in comparison with intermediate-dose prophylaxis (p = 0.042).

CONCLUSIONS

ROTEM and ETP are useful laboratory assays for monitoring efficacy of different prophylaxis regimens with concentrate of FVIII/IX in patients with severe haemophilia, helping in making decisions regarding optimal dose-regimen prophylaxis.

Assessment of the impact of treatment on quality of life of patients with haemophilia A at different ages: insights from two clinical trials on turoctocog alfa

Haemophilia and its treatment interfere with patients' life, so health-related quality of life (HRQoL) should be assessed when evaluating treatments. This study investigated the HRQoL of patients with haemophilia A treated prophylactically with a new recombinant factor VIII. Two phase 3 trials investigated turoctocog alfa in patients with severe haemophilia A: one in children, one in adults and adolescents. HRQoL was a secondary endpoint assessed by the HAEMO-QOL age-specific, self-administered questionnaires. Parent-completed versions were also included for parents of children and adolescents. All HAEMO-QOL questionnaires allow the calculation of domain-specific and total scores ranging from 0 to 100, lower scores indicating better HRQoL. Mean change in all scores was described for 25 children aged 4-7 years, 21 children aged 8-12 years, 18 adolescents aged 13-18 years and 129 adults, overall, and according to the treatment regimen received prior to the study (on-demand; prophylaxis; mixed). Mean changes in HAEMO-QOL total score were 1.4 for children aged 4-7 years, -2.6 for children aged 8-12 years, -5.8 for adolescents and -1.6 for adults. In parent-completed versions, mean changes in total score were -6.0 for children aged 4-7 years, -4.7 for children aged 8-12 years, and -10.0 for adolescents. Patients receiving on-demand treatment before the trial showed greater improvement in HRQoL scores than patients already on prophylaxis. HRQoL of patients remained fairly stable over the course of the trials. However, improvements were observed for adolescents. Switching to prophylaxis was identified as a potential driver of improvement of HRQoL in patients with haemophilia A.

Acquired hemophilia A: an underdiagnosed, severe bleeding disorder

Acquired hemophilia is a rare bleeding disorder caused by autoantibodies that inhibit coagulation factor VIII. In most cases, it manifests with severe, often life‑threatening bleeds. Acquired hemophilia may be idiopathic or secondary to another condition, most commonly other autoimmune disease or cancer. Treatment is directed to stop bleeding and eradicate inhibitory autoantibodies. Like in most life‑threatening conditions, early diagnosis and treatment are essential for good prognosis. Prompt diagnosis and treatment of acquired hemophilia are constantly improving owing to the increasing availability of laboratory diagnostic tests and growing awareness of physicians of various specialties.

Issues in pediatric haemophilia care

The hemophilias are the most common X-linked inherited bleeding disorders. The challenges in children are different from that in adults and, If not properly managed, can lead to chronic disease and lifelong disabilities. Currently, inhibitors are the most severe complication and prophylaxis is emerging as the optimal preventive care strategy. Quality of life has become in the western countries the primary objective of the process of providing care, thus all the strategies (psychotherapy, physiotherapy, community life), not just the infusion of the missing factor, should be activated for the patient and family to give them the perception of being healthy.

From principle to practice: bridging the gap in patient profiling

The standard clinical coagulation assays, activated partial thromboplastin time (aPTT) and prothrombin time (PT) cannot predict thrombotic or bleeding risk. Since thrombin generation is central to haemorrhage control and when unregulated, is the likely cause of thrombosis, thrombin generation assays (TGA) have gained acceptance as "global assays" of haemostasis. These assays generate an enormous amount of data including four key thrombin parameters (lag time, maximum rate, peak and total thrombin) that may change to varying degrees over time in longitudinal studies. Currently, each thrombin parameter is averaged and presented individually in a table, bar graph or box plot; no method exists to visualize comprehensive thrombin generation data over time. To address this need, we have created a method that visualizes all four thrombin parameters simultaneously and can be animated to evaluate how thrombin generation changes over time. This method uses all thrombin parameters to intrinsically rank individuals based on their haemostatic status. The thrombin generation parameters can be derived empirically using TGA or simulated using computational models (CM). To establish the utility and diverse applicability of our method we demonstrate how warfarin therapy (CM), factor VIII prophylaxis for haemophilia A (CM), and pregnancy (TGA) affects thrombin generation over time. The method is especially suited to evaluate an individual's thrombotic and bleeding risk during "normal" processes (e.g pregnancy or aging) or during therapeutic challenges to the haemostatic system. Ultimately, our method is designed to visualize individualized patient profiles which are becoming evermore important as personalized medicine strategies become routine clinical practice.

The principles of PK-tailored prophylaxis

While prophylaxis with factor VIII (FVIII) is considered the first choice therapy for patients with severe haemophilia A the optimal prophylaxis regimen is still under scientific debate. A recent study demonstrated efficacy and safety of a PK-tailored prophylaxis regimen with rFVIII (ADVATE) aimed to maintain FVIII trough levels of ≥1% (19). The annual bleed rate (ABR) could be significantly reduced compared to the previous on-demand treatment period (p < 0.0001) and bodily pain, a health-related quality of life dimension of the SF-36v1 questionnaire also significantly improved (p = 0.0007). Thus PK-tailored prophylaxis with ADVATE might offer a valid alternative to standard prophylaxis. Open issues to be considered for implementation of PK-tailored prophylaxis are: What FVIII trough level is needed to prevent any bleed? Do patients with target joints need higher FVIII trough levels to stay bleed-free? Are there user-friendly tools available to calculate individualized PK-driven prophylaxis doses and frequency without the need for a full 9-sample PK curve? Current knowledge on these aspects as well as some considerations about the future of PK-tailored prophylaxis is discussed.

Development of novel treatment options for patients with haemophilia

Treatment of haemophilia has vastly improved over the last years, but many needs are still unmet. Baxter is continuously pursuing the aim to provide new therapeutic options to patients with haemophilia and to their treating physicians. In fact, there are several opportunities to improve existing therapies, e.g., by new indications for existing products, the introduction of new products, and by novel therapeutic approaches other than factor replacement. Among these, Baxter is working on a number of innovations, such as pharmacokinetics-tailored factor VIII prophylaxis, bypassing agent prophylaxis with FEIBA in inhibitor patients, development of a longer acting pegylated recombinant FVIII, a new recombinant factor IX, a new recombinant factor FVIIa, the first recombinant von Willebrand factor, recombinant ADAMTS13 (a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13) as well as gene therapy to cure haemophilia B.

CONCLUSION

Baxter is truly committed to the benefit for the patient, and therefore engaged in providing a more and more individualized treatment, in increasing efficiency of current products, in developing new products and new approaches with added value.

[Severe and moderate haemophilia under prophylactic replacement treatment--maximal knee extensor and flexor torque of children and adolescents]

Due to its influence on haemophilic arthropathy, the evaluation of knee extensor (K(Ext)) and flexor (K(Flex)) torques plays an important role in the preventive and rehabilitative context of haemophilia. Thus, the present study aimed at investigating maximal static torque (M(Max)) of K(Ext) and K(Flex). 14 boys with haemophilia (8 severe, 6 moderate; age: 11.7 ± 2.8 years; prophylactic treatment > 5 years) and 14 healthy carefully pair-matched controls (age: 11.5 ± 2.7 years) were separately measured for the left and right leg for M(Max). Furthermore, the ratio K(Flex)/K(Ext )was calculated and the joint situation assessed using the Haemophilia Joint Health Score.

RESULTS

No significant group-effect was observed for M(Max) of the K(Ext) and K(Flex) as well as for the ratio K(Flex)/K(Ext) (p>0.05). Despite significant higher joint scores in haemophilic children compared to their healthy controls (p<0.01), patients merely showed minor joint impairments.

CONCLUSION

Children and adolescents with severe and moderate haemophilia under prophylactic replacement treatment with a good joint status showed comparable maximal strength performance of relevant knee muscles compared to their healthy peers.

[Haemophilia treatment centres in Germany]

An adequate number of qualified haemophilia centres is an essential requirement for effective and cost-efficient haemophilia care. During a reassessment of the delivery of haemophilia care in Germany a broad range of criteria relating to structure and quality of the centres were defined and a questionnaire was developed.

RESULTS

Of 137 doctors who received the questionnaire, 113 (82%) replied. Based on data related to diagnostic and treatment services, together with voluntary information from PEI forms (Paul Ehrlich Institut, Germany), 72 haemophilia centres were established. Three levels of haemophilia care were defined by the Medical Advisory Council of the German Haemophilia Society. This is in accordance with criteria defined by European working parties. 17 haemophilia centres were designated CCC (Comprehensive Care Centre), 24 were designated HTC (Haemophilia Treatment Centre) and 31 smallest centres were allocated the status HTR (Haemophilia Treatment Regional). In comparison to the survey in 2007, there was only slight variance in the CCC centres (+ 2 centres/-1 centre). From the previous HTC centres, 7 have withdrawn from this treatment level: 4 maintain treatment on the lower level HTR, and 3 centres had ceased treatment. On the HTR level of treatment, 6 of 29 (21%) had ceased to offer treatment. 9 had been able to increase the number of patients and were designated HTC. 5404 patients with haemophilia and 3047 with the severe form of haemophilia were reported. 67% were treated in CCC, 25% in haemophilia treatment centres and 8% in the 31 smallest centres. 13 of the adult CCC are situated in the department of internal medicine and 4 in the section of transfusion medicine.

CONCLUSIONS

The survey and analysis of the haemophilia treatment centres in Germany show that the delivery of haemophilia care through 17 CCC, 24 HCT and 31 HTR appears to be adequately structured. But it is noticeable and alarming, however, that on both HTC and HTR levels of treatment, 32% and 21%, respectively, have left their treatment level. 9 centres (12.5%) have finished working in haemophilia care in the last four years. On the strength of these results, endeavours to maintain haemophilia centres must be intensified. A high level of effective care can be guaranteed only through continued existence of the centres.

Successful long-time treatment with mycophenolate-mofetil in a child with acquired factor VIII inhibitor

Here, we report about a boy (age: 18 years) who developed an acquired factor VIII inhibitor at the age of 9 years. He presented with bleeding in his right ankle, multiple haematomas and a high-titer factor VIII type II inhibitor (400 BU).

THERAPY

He received treatment with MMF (CellCept®), dexamethasone-immunoglobulin pulses, and rituximab together with high dose FVIII (Hannover protocol). His inhibitor titer decreased rapidly, and half-life and recovery normalized. Inhibitor titres increased after reduction of the factor VIII dose, and increased further after MMF was stopped. A second treatment course with MMF again resulted in reduction of the titre, improvement in half life and recovery, and no more bleedings. Inhibitor reappeared with MMF dose reduction, again accompanied by severe bleeding. Additional rituximab stopped the bleedings, and treatment with MMF has been continued since.

CONCLUSION

Although the laboratory parameters showed no complete remission, severe bleedings and expensive factor replacement could be avoided by long-term treatment with MMF.

Evidence of prophylaxis treatment in adult haemophiliacs. Need of this treatment strategy?

In contrast to children with haemophilia the scientific evidence of prophylaxis treatment in adults is not yet proven. Existing studies are of observational character and mostly retrospectively designed. Therefore, opinion leaders in this field postulate prospectively designed, randomized, controlled and multicentric studies to set up urgently needed guidelines. Evidence according to the Canadian task force ranking is assessed as level III with a recommendation grade C by the authors. The recognition of benefits of health care providers in accordance with the German Federal Joint Committee generally demands a Grade-Ia to Ib evidence. As long as the actual evidence of prophylaxis in adult haemophiliacs does not meet the postulated criteria of the German Federal Joint Committee, prophylactic replacement therapy of the individual case has to be well documented and reasonably explained.

[Haemophilia A therapy of adults. Actual treatment situation in a haemophilia centre]

In a retrospective study from a single treatment centre (Centre for Haemostaseology Muenster) the current treatment conditions of patients with severe haemophilia A (FVIII:C <1%) at the age of ≥ 16 years are described. Data were extracted from paper based diaries of patients in home treatment (n = 70).

RESULTS

A progressive preference towards prophylactic treatment compared to on demand therapy is observed. On average 2.4 injections per week (mean: 1750 IU FVIII per injection) are used in the prophylactic regimen. The consumption of FVIII concentrates is approximately fivefold increased compared to on demand therapy (average 0.5 injections per week). Meanwhile, recombinant FVIII concentrates have become widely accepted in all age groups, they show a proportion of 60% in the clinical practice of the study population.

Secondary prophylaxis with rFVIIa in hemophilia and inhibitors: recommendations from an experts committee from Argentina

Secondary prophylaxis with rFVIIa has been the subject of several publications in the past few years. However, there is no general consensus on how this treatment should be put into practice, as publications have been very heterogeneous in the dosing schedule they report. Furthermore, the mechanism of action of rFVIIa and its short half life have been used as arguments against its role in prophylaxis. There have been a series of recent publications that show that rFVIIa can traffic through the intact endothelium and be stored in the subendothelium of several organs for a prolonged period of time. In order to consensuate the role of rFVIIa in prophylaxis, a group of experts from Argentina, resumed available information regarding pharmacology and clinical experience with this treatment, and developed a series of recommendations to use this drug in the prophylaxis setting.

Inhibitor-Immunology-Study. Different HLA-types seem to be involved in the inhibitor development in haemophilia A

The development of inhibitors is one of the most important complications of replacement therapy in haemophilia, affecting mortality and morbidity. Inhibitor development is based on complex immunological factors. Cytokines and their receptors, T-cell receptors, and the Major Histocompatibility Complex may play important roles in the development of inhibitors. Earlier studies showed non significant associations between HLA class and inhibitor development. Later studies found an increased risk of inhibitor development if there was a combination between certain factor VIII mutations and HLA antigens. We performed HLA typing in 50 patients with haemophilia A in an effort to find associations with inhibitor development.

RESULTS

25 patients had developed an inhibitor (11 low titre, 14 high titre), and 25 never had. In logistic regression analysis, HLA-A 34, DRB1 0405, DRB1 1301 seemed to be involved in inhibitor development and HLA-A 30, B 13, B15, B 57, Cw 12, DQB1 0303, DPB1 0201 protection against inhibitor development. In our patients, the HLA-associations with inhibitor development were different from those in previous publications.

[Management of pregnancy and childbirth in carriers of haemophilia]

3 pregnant women, aged 27, 33 and 31 years respectively, were carriers of haemophilia A. The first patient had a caesarean section without prior measurement or substitution of factor VIII. She gave birth to a healthy boy, but developed severe diffuse abdominal bleeding after a few hours. The second patient had a normal level of factor VIII, and lived 100 km away from the nearest haemophilia treatment centre. Ultrasound investigation revealed a female foetus. She gave birth in the local hospital. The third patient was pregnant with a male foetus, but refused further prenatal investigation. Contrary to medical advice she gave birth at home. For carriers of haemophilia, there are several options for prenatal diagnosis and managing labour and delivery. Early referral is advised and the need for adequate counselling is explained. It is important to have an experienced haemophilia treatment centre nearby, where haematologists, gynaecologists, geneticists and paediatricians cooperate in caring for pregnant carriers of haemophilia.

Advances in hemophilia: experimental aspects and therapy

This article describes recent clinical and research advances in hemophilia therapy. Different prophylactic regimens for the management of severe hemophilia are described along with the use of adjuvant treatment options to achieve hemostasis. The safety and efficacy of radionuclide synovectomy with phosphorus 32-sulfur colloid to treat existing joint arthropathy also are described. The development of inhibitors to factor VIII or IX remains a challenge for hemophilia care and recent approaches to achieve immune tolerance induction are discussed. Finally, recent advances in hemophilia are mentioned, including the role of iron, inflammation, and angiogenesis in the pathogenesis of hemophilic arthopathy.

[Haemophilia A, B or von Willebrand disease type 3. Census of patients in the eastern part of Germany]

Diagnostics and treatment of severe forms of haemorrhagic diatheses (HD), such as haemophilia A, B or type 3 von Willebrand disease (VWD) need high standards in haemophilia treatment centers (HTCs). Due to their generally low incidence, a close cooperation of haemophilia treaters is needed to optimize treatment strategies. For this purpose, the Kompetenznetz Hämorrhagische Diathesen Ost was founded. The first project was the conduction of a survey of epidemiological data of patients with HA, HB and type 3 VWD in all HTCs in the eastern part of Germany.

METHOD

The study assessed the data regarding numbers of patients treated with HA, HB or type 3 VWD, disease severity, regime of coagulation factor replacement (CFR) and the frequency of factor VIII and IX inhibitors.

RESULTS

Up to now, data of 838 patients from 27 HTCs were evaluated (5-151 per HTCs). Among the included patients, 201 were children or adolescents (<18 years). 81 children suffered from severe HA, 20 from severe HB and 10 from type 3 VWD. In 637 adults we found 246 with severe HA, 51 severe HB and 28 VWD of type 3. The most commonly used treatment of CFR in patients with severe disease was prophylactic modality. 90% of the children received prophylaxis, but also in 64% of the adults an intermittent or long-term secondary prophylaxis was the preferred treatment. At the time of survey conduction, a factor VIII or IX inhibitor was present in 1.9% of the children and in 1.6% of the adults with haemophilia.

CONCLUSION

Our data allow an overview of the number of patients and treatment strategies in the eastern part of Germany.

Quantifying adherence to treatment and its relationship to quality of life in a well-characterized haemophilia population

It is known that chronically ill patients adhere to medical treatment plans only 50% of the time. Adherence to treatment with factor infusion therapy in haemophilia patients is essential to stop bleeding. It also prevents both acute and chronic life and limb threatening complications. This study, performed in a well-described haemophilia population, was completed in an effort to understand the critical issue of adherence in patients with haemophilia. A major component of the methodology of this study was the development of a unique scoring system to quantify adherence. Adherence scores in patients on On-Demand treatment strategies were then compared to those on High Intensity treatment strategies. Quality of life (QoL) studies were also performed on the study population to assess the association of treatment regimen and adherence scores to QoL measures. Results of this study demonstrated that adherence to On-Demand therapy was significantly greater than adherence to High Intensity treatment regimens and in children, High Intensity treatment regimens, which included prophylaxis, correlated with better QoL scores in body pain. It is envisioned that the development of an objective scoring system for adherence will prove useful in future studies of adherence as well as in the development of intervention strategies that can overcome barriers to adherence in haemophilia patients.

Utilization of recombinant activated factor VII in southern Ontario in 85 patients with and without haemophilia

Recombinant activated factor VII (rFVIIa) is licensed for the treatment of bleeding in individuals with haemophilia and inhibitors. The use of rFVIIa appears to be increasing, and an increase in unlicensed use is suspected. There are currently few data about the specific indications for its use. The aim of this study was to describe the patterns of utilization of rFVIIa. We performed a retrospective cohort study using rFVIIa infusion data collected prospectively and clinical data collected retrospectively. Patients were identified using a tracking system designed to account for use of all coagulation factor concentrates issued in southern Ontario. Between 1 January 2001 and 31 December 2005, 85 patients received rFVIIa. 1164 infusions were given (8246.4 mg). Haemophilia patients with inhibitors accounted for 82.9% of rFVIIa infused and represented 8.2% of patients. The total amount of rFVIIa used increased each year from 2001 to 2004 and then decreased in 2005. The total number of infusions of rFVIIa administered annually increased. Both on-label and off-label use of rFVIIa increased. The number of patients with haemophilia receiving rFVIIa remained small and constant. The number of patients receiving rFVIIa for off-label indications increased markedly. Most rFVIIa infusions were given for licensed indications; however, these infusions represented <10% of patients treated. Overall, the utilization of rFVIIa is increasing, mostly for approved indications; however, the number of patients being prescribed rFVIIa for off-label indications has increased. The tracking system used in this study is a valuable tool to describe ongoing utilization patterns of rFVIIa.

Should prophylaxis be used in adolescent and adult patients with severe haemophilia? An European survey of practice and outcome data

A survey of 21 haemophilia doctors, throughout Europe, who care for a total of approximately 5000 patients with bleeding disorders addressing practice and opinions regarding prophylaxis in patients aged 16-24 years and adults aged over 50 years, is presented. The outcome of adolescent patients who reduced or stopped prophylaxis was recorded. Eighteen of 19 respondents would consider modification of established prophylaxis in the adolescent age group, principal considerations being avoidance of risks of further concentrate exposure, predicted poor compliance and treatment costs. The preferred age for modification was 16-20 years, but there was very little consensus on the particular prophylactic regime recommended. Approximately, half of a cohort of 218 patients with severe haemophilia successfully reduced or stopped prophylaxis when they reached adolescence. Only 26 of 92 (28%) of the patient cohort who stopped prophylaxis, required reintroduction of a prophylactic regime and 12 of 59 (20%) of those who reduced the intensity of prophylaxis had to reintroduce a more intensive regime. A majority of respondents would consider starting prophylaxis in those over 50 years. There was no consensus as to indications for this practice or the nature of the prophylaxis protocol. We conclude that there is an absence of consensus on the management of patients with severe haemophilia, as they pass through adolescence and young adulthood, and reach the age of 50. Aggregate outcome data suggest a significant proportion of patients in the 18-22 years age range may be able to reduce or stop prophylaxis. A substantial number of older patients are on prophylaxis.

A haemophilia treatment centre-administered disease management programme in patients with bleeding disorders

The objective of this study is to describe a disease management programme (DMP) for the bleeding disorder population insured by Indiana's high-risk insurance plan, and to assess the associated costs and outcomes. All bleeding disorder patients, covered by the state plan as their primary health insurance, were enrolled into a DMP administered by the Indiana Hemophilia & Thrombosis Center (IHTC). A pre/post-intervention study design was used, with 1-year pre-enrollment serving as the baseline period and 1-year post-enrollment as the study period. Claims data were used to assess hospitalizations, emergency room (ER) visits, total medical and clotting factor costs and factor units dispensed. Medical records were used to assess disease severity and other comorbidities. Thirty-one continuously enrolled patients had complete data over 2 years. Approximately 84% of the population was male, 81% with haemophilia. The average costs of care in the baseline year and the first year of the programme were $161 441 and $118 293, respectively. The decrease in the total costs was primarily attributed to a decrease in outpatient factor costs, which resulted from decreased factor utilization and lower per unit factor costs. The mean number of inpatient hospital days and ER visits for the DMP population decreased from 1.3 and 1.4 to 0.4 and 0.6, baseline and first year, respectively. Owing to the small sample size and high variability of the population, the differences were not statistically significant. The DMP appears to have reduced the total costs and resource utilization, although the study was underpowered.

Prophylactic treatment of haemophilia patients with inhibitors: clinical experience with recombinant factor VIIa in European Haemophilia Centres

Many patients with haemophilia develop inhibitors to factor VIII and require bypassing agents to provide haemostatic cover for limb- or life-threatening bleeding episodes. Due to the reduced risk of blood-borne pathogen transmission with recombinant products, on-demand recombinant factor VIIa (rFVIIa; NovoSeven is the treatment of choice for children with inhibitors. In haemophiliac patients without inhibitors, primary prophylaxis has been clinical practice for several years. This paper summarises 13 case histories of rFVIIa secondary prophylaxis for haemophilia patients with inhibitors. This was a retrospective survey of adult and paediatric severe haemophilia patients with inhibitors treated with rFVIIa from ten European Haemophilia Centres. There was a wide variation in administered rFVIIa dose, from 200-250 microg kg(-1) per week to 220 microg kg(-1) daily. In many cases, this was lower than the recommended on-demand dose of rFVIIa. In 12/13 cases, prophylaxis with rFVIIa considerably reduced the number of bleeding episodes compared with previous treatment. Eight/nine patients were satisfied or very satisfied with rFVIIa treatment, and in cases reporting subjective quality of life (QoL), all were improved, much improved, or significantly improved. In haemophilia patients with inhibitors, prophylaxis with rFVIIa is highly effective in reducing the number of bleeding episodes and results in good patient compliance and improved QoL. Randomised controlled trials are needed to confirm these findings. Results of a recently completed clinical trial on secondary prophylaxis with rFVIIa in frequently bleeding haemophilia patients with inhibitors are expected in late 2006.

A randomized, double-blind trial demonstrating bioequivalence of the current recombinant activated factor VII formulation and a new robust 25°C stable formulation

Recombinant activated factor VIIa (rFVIIa) is a well-established treatment for bleeding episodes in patients with congenital or acquired haemophilia A or B with inhibitors to factors VIII and IX and patients with FVII deficiency. The aim of this trial was to demonstrate bioequivalence between the currently marketed (rFVIIa/NovoSeven) and a new rFVIIa formulation (VII25) stable at up to 25 degrees C. Furthermore, short-term safety and tolerability of VII25 and pharmacokinetics of both formulations were investigated. In this single-centre, randomized, double-blind, two-way cross-over trial, healthy male subjects received one intravenous bolus injection of rFVIIa and one of VII25, both at 90 microg kg(-1), in a randomized order 2-3 weeks apart. Mean VII25/rFVIIa ratio for area under the plasma activity-time curve from time 0 to last quantifiable activity (primary bioequivalence endpoint), was 0.93, 90% confidence interval (CI) (0.89-0.96), within the predefined bioequivalence range (0.80-1.25). Secondary pharmacokinetic parameters were comparable between formulations. No serious adverse events were observed. Six mild or moderate treatment-emergent adverse events were reported in five subjects. Coagulation-related parameter profiles were similar between rFVIIa and VII25. No clinically abnormal changes were observed for laboratory parameters and no subjects developed FVIIa antibodies. This trial demonstrated bioequivalence between the currently available rFVIIa and VII25 stable at up to 25 degrees C. VII25's 'user-friendly' formulation removes the inconvenience of storing/transporting at 2-8 degrees C, and as the drug substance is the same, the activity and safety established for rFVIIa is maintained.

RCTs and observational studies to determine the effect of prophylaxis in severe haemophilia

It has been suggested that more RCTs should be conducted in the evaluation of haemophilia treatment, including prophylaxis. To draw valid conclusions from experimental or observational studies, internal validity should be ensured. In particular, similarity of prognosis between treatment groups compared in a particular study is needed. Because the use of prophylaxis in observational studies is nonrandomized by definition, special efforts should be made to achieve comparability of prognosis, that is, to avoid 'confounding by indication'; in RCTs this is ensured by randomized allocation of treatment. However, the high costs of an RCT results in a limitation of both patient numbers and length of follow up. Observational studies tend to be more generalizable and cheaper, as they may include a wider spectrum of morbidities, use treatment protocols in agreement with routine care, and use available data. Therefore, observational studies can be much larger and of longer duration than RCTs; and are the preferred design for the evaluation of long term treatment effects. Several valid observational studies comparing prophylaxis and on demand treatment have reported both a short term reduction of 75-90% in bleeding frequency, and significant improvement in arthropathy, quality of life, and socioeconomic parameters after more than 20 years of prophylactic treatment. RCTs provide the most powerful tool for the evaluation of short term effects of any treatment, but are infeasible for the evaluation of long term effects. The definitive assessment of the long-term benefits of prophylaxis requires observational studies that should be performed according to rigorous standards.

Partnerships in specialty care: exploring rural haemophilia provider resource needs

OBJECTIVE

The purpose of this study was to determine whether rural providers have adequate preparation for safe and effective haemophilia care.

DESIGN

This qualitative study proceeded in two phases: focus group (phase I) and telephone (phase II) interviews.

SETTING

Five Canadian rural hospitals served by one urban haemophilia treatment centre and providing service to at least one haemophilia family.

PARTICIPANTS

Phase I: focus groups of rural health professionals (site 1: n = 5; site 2: n = 6), including nursing, medicine and lab technology. Phase II: telephone interviews with nine participants from nursing, medicine, lab technology, social work and physiotherapy across three sites.

MAIN OUTCOME MEASURES

Qualitative content analysis yielded categorical themes for specialty care resource requirements in a rural context.

RESULTS

Resource needs reflected five main categories: communication network, subjective knowledge, team roles, objective knowledge and partnerships (C-STOP).

CONCLUSIONS

The five C-STOP categories require resources and alignment of urban specialist, rural provider and family expertise. Specialty clinic efforts promoting self-care are incomplete without matched resources for rural providers.