Comparing prophylaxis with episodic treatment in haemophilia A: implications for clinical practice

Summary. Recurrent haemarthroses in patients with severe haemophilia A often result in irreversible joint damage. Treatment using routine infusions of factor VIII (FVIII) concentrate, a therapy known as prophylaxis, is currently recommended for the prevention of haemarthroses and arthropathy in persons with severe haemophilia A. However, until recently, the body of evidence supporting prophylaxis in comparison with FVIII infusions given only at the time of haemarthroses was mostly retrospective and anecdotal. Recently, two prospective randomized clinical trials have been conducted to compare prophylaxis with on‐demand FVIII treatment for the prevention of arthropathy and haemarthroses in young children with haemophilia A. A third prospective, non‐randomized trial evaluated a strategy of escalating the dose frequency of prophylaxis. Data from these studies will provide objective evidence for the prevention of haemarthroses and arthropathy in children with severe haemophilia A.     

Optimal haemophilia care versus the reality

Haemophilia A and B are inherited bleeding disorders whose diagnosis and management is generally well established and best provided by specialists in a comprehensive care setting. Patients may be put at unnecessary risk if appropriate expertise is not sought for the management of accidents and surgery. The delivery of a high quality comprehensive service to patients with bleeding disorders depends upon defined standards and a network of haemophilia centres in the UK with similar models in other countries. In developing countries, despite a shortage or absence of treatment products, development of local expertise results in an improved outlook and reduction in mortality. Optimal care for severe haemophilia includes accurate diagnosis, early and adequate factor replacement for bleeding episodes and the provision of prophylaxis from an early age to prevent joint bleeding and the consequent arthropathy. Haemophilia treatment is expensive resulting in considerable inequity in provision of care across the world. Despite decades of experience, optimal treatment levels are not robustly defined. Transfusion-transmitted infections continue to have a significant impact on patient management. The development of inhibitory antibodies seriously complicates the management both in morbidity and cost. While gene therapy has not yet produced the hoped-for cure, new technologies will produce improved products.     

Current situation of regular replacement therapy (prophylaxis) for haemophilia in Japan

Summary.  We conducted a questionnaire survey of haemophilia treaters participating in the Fourth Seminar on Regular Replacement Therapy (sponsored by Baxter Bioscience, 4 March 2006) to clarify the current status (up to January 2006) of replacement therapy for haemophilia. The haemophilia treaters including medical doctor, nurse belonged to 48 institutions located in the 23 prefectures of Japan. Topics included age at the initiation of regular replacement therapy (prophylaxis), and expected future situation of patients who are currently receiving prophylaxis. Data were collected from 1267 patients with haemophilia A and 273 patients with haemophilia B who had been treated at the represented institutions. Of these haemophilia A and B patients, 23% and 16% had received a prophylactic treatment regimen respectively. A breakdown of each disease by severity demonstrated that of the patients with severe haemophilia A and B patients, 27% and 18% of patients received a prophylaxis treatment, compared to 17% and 19% of patients with moderate type, and 1% and 3% of patients with mild type respectively. Of those severe haemophilia A and B patients receiving prophylaxis, the percentage of primary prophylaxis, which means prophylaxis begins under 2 years of age, was still small for 24% and 29% respectively. However, approximately half of the patients received prophylaxis during the age of 2–14 years, which suggests that secondary prophylaxis is widely spread in the age group in Japan. Problems in introduction of prophylaxis include difficulty in peripheral venous access, a lack of understanding of the therapy by the caregiver. In addition, the fear of inhibitor development, as well as the psychological anxiety in paediatric patients, was also mentioned as barriers to initiating and continuing prophylaxis .     

VERITAS-PRN: a new measure of adherence to episodic treatment regimens in haemophilia

Summary.  Episodic treatment of bleeding disorders is defined as utilization of clotting factor concentrates in response to acute bleeding episodes to achieve haemostasis. Non-adherence to prescribed episodic regimens can limit treatment effectiveness and result in target joint formation, pain and disability. Evaluation of and interventions to promote adherence may improve health outcomes. The purpose of this study was to validate a new adherence scale developed for individuals with bleeding disorders treated on episodic infusion regimens, entitled VERITAS-PRN [Validated Hemophilia Reg i men Treatment Adherence Scale – PRN]. Participants were recruited from the Indiana Hemophilia and Thrombosis Center patient population. Participants completed the scale for psychometric development and analysis. Subjective ratings of adherence from participants and providers were used for validation. The study sample included 51 male and three female patients. Twenty-seven participants (50.0%) were diagnosed with FVIII deficiency, 21 (38.9%) with FIX deficiency and six (11.1%) with von Willebrand's disease (VWD). Internal consistency reliability for the total VERITAS-PRN score and the majority of subscales was good-to-excellent, with the one exception being the 'Plan' subscale. Test-retest reliability correlations were good-to-excellent for the total scale and all subscales. The VERITAS-PRN total scale had moderate-to-strong and statistically significant correlations with validity measures. The VERITAS-PRN is a reliable and valid measure of adherence to episodic treatment regimens for bleeding disorders. This tool may be utilized as a standard measure of adherence to increase sensitivity to adherence problems and promote targeted interventions to enhance adherence and health outcomes     

Experience of prophylaxis treatment in children with severe haemophilia

The practice of prophylactic treatment of boys with severe haemophilia has been evaluated in our centre. Prophylaxis was started at the median age of 3.7 years (range 0.4-12.7 years) in 38/41 children (93%) under 17 years of age. Median follow-up was 4.1 years (range 0.4-12.7 years). The criteria of primary prophylaxis according to the definition by the European Paediatric Network of Haemophilia Management was fulfilled by 9/38 (24%). Although a majority [76%, 29/38] of the children started prophylaxis after a median number of joint bleeds of 3.5, 70% of the children in this group had clinical joint scores of 0. Intravenous catheter insertion was required at a median age of 15.5 months (range 5-36 months) in 21% of the children, resulting in a catheter infection rate of 1.74 per 1000 catheter days. None developed an inhibitor on prophylaxis and three patients who had low-titre inhibitors (< 5 Bethesda units) prior to prophylaxis had undetectable inhibitors after prophylaxis. The home-treatment training programme required considerable time and cost. As a result, 87% of the children used peripheral venous access and hospital visits declined as prophylaxis became established. Parents' incentives for prophylaxis were that the children undertook many physical activities and sports previously not recommended, there was less parental anxiety and an overall improvement in the quality of life for the whole family.     

FEIBA prophylaxis in haemophilia patients: a clinical update and treatment recommendations

Summary.  In patients with severe haemophilia and inhibitors, regular factor VIII inhibitor bypassing activity (FEIBA) prophylaxis has been shown to reduce the frequency of bleeding by up to 85% and to improve patient quality of life. FEIBA is well tolerated; the incidence of thrombotic events and of allergic reactions is extremely low. The concept of prophylaxis in haemophilia patients with inhibitors is relatively new and some clinicians may be unsure of how to use FEIBA in this context. These treatment recommendations, based on published evidence plus the collective experience of a group of haematologists (with practical knowledge of managing inhibitor patients with FEIBA prophylaxis), are intended to provide guidance to clinicians considering initiating and maintaining patients on FEIBA prophylaxis with specific focus on practical aspects of patient selection, dosing, monitoring and stop criteria.     

Secondary prophylaxis treatment versus on‐demand treatment for patients with severe haemophilia A: comparisons of cost and outcomes in Taiwan

Summary. This study compared secondary prophylaxis treatment with on‐demand treatment for severe haemophilia A in Taiwan. Fifty patients from one medical centre were evaluated over a 5‐year period. Differences in annual bleed rates and factor VIII (FVIII) utilization were assessed between patients receiving secondary prophylaxis and patients receiving FVIII concentrates on‐demand. Results were then used as inputs in a pharmacoeconomic model to predict outcomes of future haemophilia therapy strategies in Taiwan. The median annual number of total bleeding episodes was significantly lower in the 13 (26%) patients who received secondary prophylaxis than in the 37 patients who received FVIII on‐demand (7.76 vs. 31.91, P < 0.0001). The between‐group difference in median annual factor VIII utilization was statistically significant (1824.41 IU kg^?1 for the prophylaxis group and 1324.81 IU kg^?1 for the on‐demand group, P < 0.01). It was estimated that approximately $2 million (USD) per year would be added to the cost of treatment by having all severe haemophilia A patients in Taiwan receive secondary prophylaxis instead of on‐demand therapy while 12 566 bleeding will be prevented. It is recommended that National Health Insurance officials utilize these data to evaluate the benefits of enhanced treatment strategies and before making substantial policy changes to haemophilia care in Taiwan.     

Influence of medical insurance schemes and charity assistance projects on regular prophylaxis treatment of the boys with severe haemophilia A in China

Objective

To explore the influence of medical insurance policy and charity assistance projects on the uptake and discontinuation of regular prophylaxis treatment in Chinese severe haemophilia A children.

Methodology

This retrospective study was conducted on children with severe haemophilia A, who received FVIII prophylaxis treatment at 12 haemophilia centres in China from 1 November 2007 to 31 May 2013.

Results

The average duration of prophylaxis treatment received by haemophilia children significantly increased from 16.7 weeks in 2008 to 32.8 weeks in 2012 (P < .001). The main reason for prophylaxis acceptance included dissatisfaction with previous “on‐demand” regimens, availability of improved local medical insurance policies and patient/family awareness of haemophilia. The main reason for subsequent discontinuation of prophylaxis was economic instability. The upper limit of insurance was up to RMB 150 000/y (~USD: 22 000/y) for 80.1% of the insured patients and would be sufficient to cover the continuous low‐dose prophylaxis regimen. However, for many patients the burden of out‐of‐pocket copayment cost represented a risk for poor adherence to regular prophylaxis. In about two third of the patients, the annual out‐of‐pocket copayment cost amounted to >50% of their average annual disposable income. Many patients therefore required assistance from the charity assistance projects, but nonadherence remained prevalent.

Conclusion

Medical insurance policy and charity assistance projects helped haemophilia children to accept and continue prophylaxis regimens. It was the proportion of the out‐of‐pocket copayment cost rather than the upper limit of insurance reimbursement that restricted long‐term regular low‐dose prophylaxis in China.     

A survey of factor prophylaxis in boys with haemophilia followed in North American haemophilia treatment centres

Summary.  A survey was conducted in 2002 to determine the pattern of factor prophylaxis use in boys ≤18 years of age with haemophilia followed in North American treatment centres. Responses were obtained from 4553 cases (74% haemophilia A, 26% haemophilia B). The frequency of prophylaxis, defined as factor infusion greater than or equal to once per week for ≥45 weeks per year, was significantly higher for haemophilia A vs. haemophilia B cases (51% vs. 32%, P < 0.0001), and for boys with severe haemophilia A living in Canada vs. the USA (77% vs. 47%, P < 0.0001). Use of full-dose prophylaxis, defined as the infusion of 25–40 IU kg⁻¹ of factor VIII on alternate days (minimum three times per week) or 25–40 IU kg⁻¹ of factor IX twice weekly, was similar for boys ≤5 years of age in both Canada and the USA (30% and 33% haemophilia A and 35% and 13% haemophilia B). Reasons for initiating prophylaxis included a history of joint bleeding (88%) and age ≤2 years (23%). For prophylaxis triggered by joint bleeding, 38% of haemophilia treatment centres indicated that they would initiate prophylaxis after the first joint bleed and 66% after a history of target joint bleeding, defined most frequently as 2–4 bleeds over a 3–6 consecutive month period. A central venous line was used to ensure easy venous access for full-dose prophylaxis therapy in 80% of boys ≤5 years of age. These data offer a basis for projecting long-term factor concentrate needs for persons with haemophilia living in North America.     

A comparison between prophylaxis and on demand treatment for severe haemophilia

Patients with severe haemophilia can be treated for bleeding either prophylactically or on demand. Each treatment modality has advantages and disadvantages from both a medical and economic point of view. This study aims to find which modality requires more units of clotting factors per body weight per year and to compare the number of bleeds between the two. The study sample consisted of 133 patients with severe haemophilia A and B treated in the Katharine Dormandy Haemophilia Centre at the Royal Free Hampstead NHS Trust in London. The average number of clotting factors used per body weight per year was 2181.7 units for prophylaxis vs. 711 units for on demand treatment (P = 0.000). Although more units used means more money spent, and although prophylaxis has additional complications, namely venipunctures and increased risk of viral contamination, other criteria must be considered including the total number of bleeds and health-related quality of life. The total number of bleeds per year was significantly (P = 0.021) less for prophylactically (7.4) vs. on-demand treated patients (11.4). This suggests that prophylaxis reduces the risk of arthropathies, the number of future hospital visits and orthopaedic surgeries, and is thus the optimal modality of treatment for patients with severe haemophilia.     

Aspects of haemophilia prophylaxis in Sweden

Summary.  Prophylactic treatment of haemophilia has been gaining acceptance as the optimal therapeutic option in an increasing number of haemophilia centres in the developed world in recent years. This paper focus on three aspects of prophylactic therapy: when to start treatment, venous access and the dose/dose interval. Evidence is in favour of prophylactic treatment to be started at an early age using either a peripheral vein with 1–2 injections per week and a successive increase in the frequency depending on the child and the veins, or, using a Port-A-Cath which allows a better prophylactic coverage by infusions preferably every second day in haemophilia A and every third day in haemophilia B.     

The use of prophylaxis in 2663 children and adults with haemophilia: results of the 2006 Canadian national haemophilia prophylaxis survey

Summary. Prophylaxis is standard of care for boys with severe haemophilia A. Indications for prophylaxis in adulthood, non‐severe haemophilia A, haemophilia B and haemophilia with inhibitors are less well defined. This survey, conducted in 2006, aimed to describe prophylaxis use in patients of all ages and severities with haemophilia A or haemophilia B in Canada. Data on 2663 individuals (2161 haemophilia A; 502 haemophilia B), including 78 inhibitor‐positive patients, were returned by 22/25 Canadian haemophilia treatment centres. This represented 98% of the Canadian haemophilia population. Frequency of prophylaxis use, defined as infusion of factor VIII/IX concentrate at least once weekly for ≥45 weeks of the year, was highest in individuals with severe haemophilia A (69%). It was lower in individuals with severe haemophilia B (32%), moderate haemophilia A (18%) or B (5%) and mild haemophilia A (1%) or B (1%). Among individuals with severe haemophilia A, the frequency of prophylaxis use was 84% in children (≤18 years) and 55% in adults (>18 years). Thirteen per cent of inhibitor‐positive individuals were receiving prophylaxis with bypassing agents. Comparison with data obtained from a 2002 Canadian survey showed a greater use of prophylaxis in children ≤5 years of age with severe haemophilia A (73% vs. 49%). Prophylaxis is no longer confined to children with severe haemophilia A, but is used in a significant proportion of adults with severe haemophilia A and individuals with severe haemophilia B or moderate haemophilia A. Prophylaxis is being started earlier in boys with severe haemophilia A.     

Survey of current prophylaxis practices and bleeding characteristics of children with severe haemophilia A in US haemophilia treatment centres

Summary. Every other day (qod) factor VIII prophylaxis prevents joint bleeds in children with severe haemophilia A. Although three times weekly or qod prophylaxis is recommended by the National Hemophilia Foundation (NHF), how widely these practices have been adopted is not known. We sought to define current prophylaxis practices at US haemophilia treatment centres (HTCs). An email survey was distributed to US HTCs, utilizing web‐based membership rosters of the Centers for Disease Control (CDC) and the Hemostasis Thrombosis Research Society (HTRS). Of 62 HTCs responding, prophylaxis is initiated on a three times weekly schedule in 29 (46.8%), twice weekly in 13 HTCs (21.0%) and once weekly in 20 HTCs (32.2%). Central venous catheters are used to infuse factor prophylactically at 55 HTCs (88.7%), including in 100% of children initiating prophylaxis at 19 HTCs (30.6%) and in 50% of those at 41 HTCs (66.1%), but avoided altogether at seven HTCs (11.3%). Prophylaxis is initiated after one or more bleeds in 56 HTCs (90.3%), but after the first bleed in only 28 HTCs (25.2%). Among 226 newborns with severe haemophilia A in 62 HTCs, 1.82 births/HTC/year, the median age at first bleed, excluding circumcision, is 7 months. Of the 113 (53.5%) newborns who underwent circumcision, 62 (54.9%) bled. Despite a recommended standard of three times weekly prophylaxis, over half of surveyed HTCs do not follow these guidelines, and nearly one‐third begin prophylaxis on a once weekly schedule to delay or avoid the need for central venous access.     

Prevention and treatment of musculoskeletal disease in the haemophilia population: role of prophylaxis and synovectomy

Summary.  Prophylaxis is defined as primary (started before the onset of joint damage) or secondary (started after the onset of joint damage). The aim of primary prophylaxis is to prevent recurrent bleeding into joints and the development of chronic arthropathy in later life. When started early, and at most after two joint bleeds, the result is predictably excellent if there is compliance with the primary prophylaxis regimen. In order to decrease the need for central venous access devices to assure reliable venous access, a number of centres start primary prophylaxis with once weekly infusions with dose-escalation based on frequency of joint bleeding. A major unanswered question is whether primary prophylaxis can be safely discontinued in adolescents/young adults and if so, when. A promising predictor for the milder bleeding phenotype in persons with severe haemophilia is a later onset of joint bleeding. Once joint damage has occurred as a result of recurrent bleeding, secondary prophylaxis can only retard, but not prevent, ongoing joint damage. Other strategies to decrease recurrent bleeding from target joints include surgical synovectomy (ideally performed using an arthroscopic technique), radionuclide synovectomy and chemical synovectomy. These interventions have very good outcomes when performed by an experienced team. Given the very high cost of factor concentrates required for programmes of prophylaxis prospective studies that document benefits to the child and family, e.g. quality of life are to be encouraged.     

Adverse events in the prophylaxis of haemophilia

Summary.  Whilst prophylaxis undoubtedly offers many advantages, the potential for adverse effects must also be borne in mind. Modern plasma-derived products have an extremely good safety record with regard to transmission of pathogens, although continuous vigilance is required as new pathogens continue to emerge, eg new variant Creutzfeldt-Jakob disease. There is no evidence that prophylactic treatment is associated with an increased incidence of inhibitors, and it is now recognized that genetic factors are the most significant in conferring susceptibility. Although subtle immunological abnormalities have also been observed in patients with haemophilia, there is no evidence that these are of any clinical significance. There has been a growing trend to use indwelling venous catheters for prophylaxis. The risk of infection has been appreciated for some time, although it has only recently been possible to quantify this with more precision. The risk of catheter-associated thrombosis is now recognized to be higher than hitherto appreciated. Whilst sporting activities are to be encouraged, there is a potential for significant trauma in children with prophylaxis, as plasma coagulation factor levels remain far below normal with the usual regimens.