Intermediate-dose versus high-dose prophylaxis for severe hemophilia: comparing outcome and costs since the 1970s

Treatment patterns and bleeding outcomes in persons with severe hemophilia A and B in a real-world setting

The current standard of care treatment for severe hemophilia A and B (SHA and SHB) is the prophylactic intravenous replacement of coagulation factor VIII or IX (FVIII/FIX) to prevent spontaneous bleeding. Persons with hemophilia without prophylactic treatment receive therapy in case of bleeding, i.e., on demand. To assess treatment patterns, utilization of products, and bleeding outcomes in a real-world cohort of persons with SHA and SHB, defined as FVIII or FIX activity < 1%, data was retrospectively collected from hemophilia-specific patient diaries used for home treatment, medical records, and entries into the Austrian Hemophilia Registry from the year 2012 to 2017. Fifty-three male persons with SHA (n = 47) and SHB (n = 6) were included; 26 with SHA and 5 with SHB were on prophylaxis, 8 and 1 switched therapy regimen, and 13 and 0 received on-demand therapy. Persons on prophylaxis used a mean factor FVIII or FIX dose of 71.7 and 40.1 IU/kg/week. Median (IQR) annualized bleeding rates (ABR) in SHA were 28.0 (23.4-31.3) in the on-demand, 4.9 (1.6-13.5) in the prophylaxis group, and 3.0 (2.0-6.8) in the prophylactic group of SHB. Three persons with SHA had zero bleeds during the observation period. On-demand therapy and hepatitis B and C were associated with higher ABR but not age, weight, and HIV positivity. Bleeding rates and the proportion of on-demand therapy in persons with hemophilia were high in our real-world cohort. Further improvement is needed, which might be facilitated with the advent of factor products with extended half-life or non-factor therapies.

Biochemical marker research in hemophilic arthropathy: A systematic review

Hemophilic arthropathy (HA) causes major morbidity. Breakthrough therapies reduce the bleeding frequency tremendously, but well-defined joint outcome assessments with a focus on early changes and subclinical damage are lacking. Biomarkers reflecting joint tissue turnover/inflammation might be useful to predict invalidating arthropathy. This systematic review summarized and categorized publications on blood/urinary biomarkers in HA to provide leads for implementation. A PubMed/EMBASE search was performed on September 9, 2019. All publications were assessed and allocated to one or several BIPED-categories, based on the utility of biomarkers. Of the initial 1307 publications found, 27 were eligible for inclusion. The majority (81%, n = 32/42) was cross-sectional in design, including relatively small numbers of patients (median 44, interquartile range 35-78). Fourteen percent (n = 6/42) investigated dynamic changes around a bleeding or treatment. Only two studies investigated the prognostic value of biomarkers. Most promising biomarkers were serum Coll2-1, COL-18N, COMP, C1,2C, C2M, CS846, MIF, plasma sVCAM-1 and urinary CTX-II. Comparing performances and pooling data was not possible due to heterogeneity. Currently, biomarker research in HA is still in an explorative stage and not yet sufficient for translation into daily practice. Clearly, larger homogeneous longitudinal studies in well-defined populations should be performed for further development.

Characterisation of healthcare utilisation and cost of haemophilia care in real-life: A 4-year follow-up study in Finland

INTRODUCTION

Characterisation of outcomes and costs of haemophilia care in common practice settings is essential for evaluation of new treatment options and for developing clinical practices. In Finland, haemophilia care is mostly centralised to University Hospitals, but treatment practices and costs in adult patients have not been systematically evaluated.

AIM

This study was designed to characterise healthcare resource utilisation and treatment costs of adult inhibitor-negative haemophilia patients managed in Finnish University Hospitals.

METHODS

The study was based on a nationwide cohort, which consists of all adult haemophilia A (HA; n = 120) and B (HB; n = 35) patients treated in University Hospitals from 2012 to 2016. Patient characteristics and data on healthcare utilisation and factor replacement use were collected from medical records. Direct costs of care were evaluated based on wholesale drug prices and healthcare service utilisation with standard unit costs.

RESULTS

Most of HA (79%, n = 96) and HB (84%, n = 31) patients received factor replacement therapy. The median annual bleeding rate (ABR) was low, at 0.8 for HA and 0.5 for HB, also among the patients with on-demand therapy. Over 94% (n = 149) of the patients had outpatient visits during the follow-up period. The mean total annual costs of treatment ranged from €2520 to €176,330. The highest individual cost was factor replacement therapy.

CONCLUSION

The outcomes of centralising the management of care to University Hospital Treatment Centres show low ABR and lower treatment costs compared with earlier reports from other high-income European populations. Management strategies, including choosing the right therapy between prophylaxis and on-demand, has been successful in Finland.

[Orthopedic treatment of musculoskeletal disorders in hemophilic patients]

Objective: To study the orthopedic treatment strategy for hemophilia complicated with musculoskeletal disorders as well as the peri-operative consumption of clotting factor. Methods: Total 338 orthopedic surgeries were performed for 261 patients, average age of 30.6 y (6-65 y) , with hemophilia between January 1996 and December 2019 at our institute. Two hundred and twenty-six patients presented with bleeds within the joints. Sixty-one patients presented with intramuscular bleeds, 45 presented with hemophilic pseudotumors, and six presented with miscellaneous complaints. Strategy of clotting factor replacement therapy was designed as per differences in the level of the operation procedure. Information regarding clinical manifestation, operative strategy, clotting factor consumption, and re-operation for complications was retrospectively recorded. The costs for multiple joint procedure and single joint procedure were studied. Results: We found that 270 of the 338 surgical procedures were major surgical procedures (79.9%) . There were 203 procedures of joint arthroplasty (60%) . Fourteen patients underwent reoperations for local recurrence (4.2%) . The average factor Ⅷ consumption before the surgery was 44.4 ± 8.1 IU/kg. The average FⅧ consumption within postoperative 2 weeks was 40 962 IU (647±177 IU/kg) . Seven type A hemophilic patients developed F Ⅷ inhibitor following the surgical procedure, with an average level of 13.7±11.2 BU/mL. Sixty-eight patients underwent multiple joint procedures under one anesthesia session (26%) . There was no significant difference in the factor consumption between the multiple joint procedure and single joint procedure. Conclusions: Surgical treatment was found to be effective for hemophilic arthropathy and lesion of the musculoskeletal apparatus, with the clotting factor replacement therapy. Multiple joint procedures under one anesthesia were more cost effective for patients with hemophilia, with less factor consumption than staged single joint procedure.

Understanding Early Hemophilic Arthropathy in Children and Adolescents Through MRI T2 Mapping

BACKGROUND

Persons with hemophilia experience hemarthrosis, which can lead to cartilage degeneration, causing physical impairment. MRI T₂ mapping has the potential to be used as a tool to evaluate early arthropathic changes and cartilage degeneration in patients with hemophilia.

PURPOSE

To assess the value of MRI-T₂ mapping as a tool for investigating the cartilage status of children and adolescents with hemophilic arthropathy.

STUDY TYPE

Prospective, cross-sectional.

SUBJECTS

Twenty-eight boys with hemophilia (aged 5-17 years) and 23 healthy boys (aged 7-17 years).

FIELD STRENGTH/SEQUENCES

A multiecho spin-echo T₂ -weighted gradient echo sequence was used on a 3.0T magnet.

ASSESSMENT

MRI-T₂ maps of ankle (tibia-talus) (n = 19) or knee (femur-tibia) (n = 9) cartilage were assessed in hemophilia and healthy groups. An anatomically-based MRI score was also assigned to each ankle/knee.

STATISTICAL TESTS

Pearson's correlation coefficient (r), linear regression, intraclass correlation coefficient (ICC), and analysis of variance (ANOVA) test.

RESULTS

Negative associations between age and ankle/knee cartilage T₂ relaxation times were found in hemophilia (r = -0.72 [P = 0.03] to -0.55 [P = 0.01]) and healthy (r = -0.84 [P < 0.001] to -0.55 [P = 0.20]) groups. There were nonsignificant associations between ankle cartilage T₂ relaxation times and MRI scores (r = -0.15 [P = 0.54] to 0.31 [P = 0.19]).

DATA CONCLUSION

Results of this clinical investigation emphasize the potential importance of MRI-T₂ maps as a tool to understand the functional status of cartilage in children and adolescents with hemophilic arthropathy, while holding promise for the detection of early cartilage degeneration prior to macroscopic characterization by conventional MRI. MRI-T₂ mapping may provide novel information that is not reflected in the anatomically-based MRI scoring system.

LEVEL OF EVIDENCE

3 TECHNICAL EFFICACY STAGE: 2.

Evaluating international Haemophilia Joint Health Score (HJHS) results combined with expert opinion: Options for a shorter HJHS

Introduction

The Hemophilia Joint Health Score (HJHS) was developed to detect early changes in joint health in children and adolescents with haemophilia. The HJHS is considered by some to be too time consuming for clinical use and this may limit broad adoption.

Aim

This study was a first step to develop a shorter and/or more convenient version of the HJHS for the measurement of joint function in children and young adults with haemophilia, by combining real‐life data and expert opinion.

Methods

A cross‐sectional multicenter secondary analysis on pooled data of published studies using the HJHS (0‐124, optimum score 0) in persons with haemophilia A/B aged 4‐30 was performed. Least informative items, scoring options and/or joints were identified. An expert group of 19 international multidisciplinary experts evaluated the results and voted on suggestions for adaptations in a structured meeting (consensus set at ≥ 80%).

Results

Original data on 499 persons with haemophilia from 7 studies were evaluated. Median age was 15.0 years [range 4.0‐29.9], 83.2% had severe haemophilia and 61.5% received prophylaxis. Median (IQR) HJHS total was 6.0 (1.0‐17.0). The items 'duration swelling' and 'crepitus' were identified as clinically less informative and appointed as candidates for reduction.

Conclusion

Analysis of 499 children and young adults with haemophilia showed that the HJHS is able to discriminate between children and adults and different treatment regimens. Reduction of the items 'duration swelling' and 'crepitus' resulted in the HJHS_short, which had the same discriminative ability. Additional steps are needed to achieve a substantially shorter HJHS assessment.

Long-term safety and efficacy of N8-GP in previously treated adults and adolescents with hemophilia A: Final results from pathfinder2

BACKGROUND

N8-GP (turoctocog alfa pegol; Esperoct® , Novo Nordisk A/S, Bagsvaerd, Denmark) is a glycoPEGylated human recombinant factor VIII with a half-life of ~1.6-fold of standard FVIII products. pathfinder2 (NCT01480180) was a multi-national, open-label trial of N8-GP in previously treated adolescent and adult patients with severe hemophilia A.

OBJECTIVE

We report end-of-trial efficacy and safety of N8-GP from pathfinder2.

METHODS

pathfinder2 main phase and extension phase part 1 results have been previously reported. During extension phase part 2, patients could switch from N8-GP prophylaxis 50 IU/kg every fourth day (Q4D) or 75 IU/kg once weekly (Q7D), depending on bleeding status. Extension phase part 2 collected long-term safety and efficacy data for all regimens until trial end (first patient in main phase, 30 January 2012; trial end, 10 December 2018).

RESULTS

Overall, 186 patients were exposed to N8-GP for up to 6.6 years (median 5.4 years). The estimated annualized bleeding rate (ABR) was 2.14 (median 0.84) for the Q4D prophylaxis arm and 1.31 (median 1.67) for the Q7D prophylaxis arm. Nearly 30% of patients experienced zero bleeds throughout the entire duration of the trial, the hemostatic response was 83.2% across all treatment arms, and patient-reported outcomes were maintained or slightly improved. No safety concerns were detected.

CONCLUSION

Data from the completed pathfinder2 trial, one of the largest and longest-running clinical trials to investigate treatment of severe hemophilia A, demonstrate the efficacy and safety of N8-GP in previously treated adolescent and adult patients.

Initial joint bleed volume in a delayed on-demand treatment setup correlates with subsequent synovial changes in hemophilic mice

BACKGROUND

Hemophilic arthropathy is a debilitating morbidity of hemophilia caused by recurrent joint bleeds. We investigated if the joint bleed volume, before initiation of treatment, was linked to the subsequent degree of histopathological changes and the development of bone pathology in a mouse model of hemophilic arthropathy.

METHODS

FVIII knock-out (F8-KO) mice were dosed with a micro-CT blood pool agent prior to induction of hemarthrosis. Eight hours after induction, the bleed volume was quantified with micro computed tomography (micro-CT) and recombinant FVIII treatment initiated. On Day 8, inflammation in the knees was characterized by fluorescence molecular tomography. On Day 14, knee pathology was characterized by micro-CT and histopathology. In a second study, contrast agent was injected into the knee of wild-type (WT) mice, followed by histopathological evaluation on Day 14.

RESULTS

The average joint bleed volume before treatment was 3.9 mm3. The inflammation-related fluorescent intensities in the injured knees were significantly increased on Day 8. The injured knees had significantly increased synovitis scores, vessel counts, and areas of hemosiderin compared to un-injured knees. However, no cartilage- or bone pathology was observed. The bleed volume before initiation of treatment correlated with the degree of synovitis and was associated with high fluorescent intensity on Day 8. In F8-KO and WT mice, persistence of contrast agent in the joint elicited morphological changes.

CONCLUSION

When applying a delayed on-demand treatment regimen to hemophilic mice subjected to an induced knee hemarthrosis, the degree of histopathological changes on Day 14 reflected the bleed volume prior to initiation of treatment.

Development and evaluation of the population pharmacokinetic models for FVIII and FIX concentrates of the WAPPS-Hemo project

BACKGROUND

The Web-Accessible Population Pharmacokinetic Service (WAPPS) project generates individually predicted pharmacokinetic (PK) profiles and tailored prophylactic treatment regimens for haemophilic patients, which rely on a set of population PK (PopPK) models providing concentrate-specific priors for the Bayesian forecasting methodology.

AIM

To describe the predictive performance of the WAPPS PopPK models in use on the WAPPS-Hemo platform.

METHODS

Data for modelling include dense PK data obtained from industry sponsored and independent PK studies, and dense and sparse data accumulated through WAPPS-Hemo. WAPPS PopPK models were developed via non-linear mixed-effect modelling taking into account the effects of covariates and between-individual-and sometimes between-occasion-variability. Model evaluation consisted of (a) prediction-corrected Visual Predictive Check (pcVPC), (b) Limited Sampling Analysis (LSA) and (c) repeated hold-out cross-validation.

RESULTS

Thirty-three WAPPS PopPK models built on data from 3188 patients (ages 1-78 years) under treatment by factor VIII or IX products (FVIII, FIX) were evaluated. Overall, models exhibit excellent performance characteristics. The pcVPC shows that the observed PK data fall within acceptable 90% interpercentile predictive bands. A slight overprediction beyond the expected half-life, an anticipated result of using sparse data, occurs for some models. The LSA results in lower than 3% of relative error for FVIII and FIX products and 16% for engineered FIX products. Cross-Validation analysis yields relative errors lower than 1.5% and 1.4% in estimates of half-life and time to 0.02 IU/mL, respectively.

CONCLUSION

The WAPPS-Hemo models consistently showed excellent performance characteristics for the intended use for Bayesian forecasting of individual PK profiles.

Exploring the Potential Feasibility of Intra-Articular Adeno-Associated Virus-Mediated Gene Therapy for Hemophilia Arthropathy

Hemophilia arthropathy (HA) represents the majority of morbidity in severe hemophilia patients, especially in resource-limited countries. Adeno-associated virus (AAV)-mediated gene therapy is showing promise for managing hemophilia. However, patients with neutralizing antibodies (NAbs) against AAV, and inhibitors to clotting factors, are excluded from such therapy. This study explored the feasibility of AAV-mediated local gene therapy for HA. Factor VIII knockout (FVIII^-/-) mice, with or without a FVIII inhibitor, were subjected to hemarthrosis induction and treated with either intravenous (IV) or intraarticular (IA) recombinant human factor VIII (rhFVIII). To investigate whether rhFVIII carried the risk to develop a FVIII inhibitor, FVIII^-/- mice were treated with three doses of IV or IA rhFVIII and inhibitor development was measured. In patients with established HA requiring synovial fluid aspiration, plasma, and synovial fluid were collected and measured for anti-AAV capsid IgG (serotypes 1-9 and 843) and NAbs for AAV843. IA rhFVIII provided better protection from synovitis compared with IV rhFVIII, with or without the FVIII inhibitor. While IV rhFVIII led to all FVIII^-/- mice developing an FVIII inhibitor (n = 31, median 4.9 Bethesda units [BU]/mL), only 50% of the mice developed a FVIII inhibitor by IA administration, and at a lower titer (median 0.55 BU/mL). In hemophilia patients, total anti-AAV IgG was lowest for AAV4 and AAV5, both in plasma and synovial fluid. Anti-AAV IgGs in synovial fluid for most samples were lower or similar to the plasma levels. These results show that direct IA rhFVIII administration yields better protection against bleeding-induced joint damage, even in the presence of an inhibitor antibody. IA rhFVIII delivery carried a lower risk of FVIII inhibitor formation compared with IV FVIII. The anti-AAV antibody level in synovial fluid was similar or lower than the plasma level, supporting the feasibility of local gene therapy for managing HA.

Pharmacokinetic-tailored approach to hemophilia prophylaxis: Medical decision making and outcomes

BACKGROUND

Clinical application of population pharmacokinetics (popPK) is of increasing interest to patients with hemophilia, providers, and payers. Routine use of popPK profiles in factor replacement prophylaxis decision making has the potential to maintain or improve efficacy and reduce product consumption.

AIM

To investigate the feasibility of implementation and longitudinal assessment of pharmacokinetic (PK)-tailored prophylaxis in routine clinical practice for hemophilia A and to describe factors that influence decision making for prescribed hemophilia prophylaxis.

METHODS

This longitudinal, multicenter, prospective feasibility study of children and adults with hemophilia A without inhibitors used the Web Accessible Population Pharmacokinetic Service-Hemophilia (WAPPS-Hemo) to generate PK profiles. Assessments over 12 weeks captured data on prescribed prophylaxis, popPK tool use, provider decision making, and patient-reported outcomes.

RESULTS

Eighteen participants aged 6 to 39 years enrolled; half used extended half-life concentrates. Patient interest in their PK centered on general curiosity followed by a desire for participation in physical activity and decrease in infusion frequency. Providers used the WAPPS clinical calculator feature to simulate prophylaxis regimens under different dose, infusion, and trough conditions. Most targeted troughs were 1 to 3 IU/dL. The feasibility assessment demonstrated challenges with patient recruitment; however, the majority of participants successfully completed study assessments meeting feasibility targets.

CONCLUSION

A larger-scale study powered to evaluate the impact of PK-tailored prophylaxis on clinical and patient-reported outcomes is feasible with study design modifications to support increased recruitment rate. Shared decision making incorporating patient and provider goals is important and facilitated by regimen simulations with the clinical calculator.

Identification of the Profile of the Patients with Hemophilia B Eligible for Treatment with Nonacog Alfa Once-Weekly

This study aimed to identify the characteristics of patients with hemophilia B eligible for once-weekly treatment with Nonacog alfa. Methods: A survey was conducted in 14 Hemophilia (HCs) of Italy. These centers were given a questionnaire consisting of ten closed multiple-choice questions. The centers were asked: (a) the percentages of their hemophilia B (HB) patients undergoing replacement therapy, “On-demand”, or weekly prophylaxis, (b) the criteria guiding the monitoring of patients, the advantages according to the age of patients, and (c) the obstacles to prophylaxis. The percentage of patients receiving “On-demand” (OD) treatment or continuous prophylaxis (prophy) differed depending on patient age and the severity of the disease. Only 57% of HCs provided “On-demand” therapy to the mild HB patients, about 93% to moderate ones, of whom 43% on prophylaxis. About 78% of patients <6 years old, were on treatment in 9 out of 14 HCs, by prophylaxis 66.7% and 33.3% by On-demand. In the 6–18 age group, 90.1% of HCs treated HB patients with prophylaxis, 42.8% in the 18–30 age range. On-demand treatment was the therapy of choice in 61.5% of HCs for patients aged 30–65 years. In total, 64% of the HCs assigned the maximum score to bleeding frequency, especially in the <6 and 6–18 age groups. Bleeding severity was also taken into significant consideration, particularly in subjects up to 30 years old. The scores regarding venous access were distributed relatively evenly throughout all age groups. The majority of the centers attributed a medium-high score to treatment compliance, especially in the 6–65 age range. In actuality, 55% of HCs attributed pro-thrombotic comorbidity a low score in the 18–30 age group, whereas 81% gave pro-hemorrhagic comorbidity a high rating in patients aged >65 years old. Many centers assigned a medium-high score to the baseline concentration of FIX level at diagnosis in all age groups. Most HCs attributed a medium-high score to type of genetic mutation in the younger age groups. As for socio-cultural barriers and quality of life, the majority of respondents gave a medium-high score in all age groups. For periodic monitoring of patients receiving continuous prophylaxis, 59% of the centers reported using clinical assessment. With regard to prophylaxis administration method, the majority of hemophiliacs were given infusions twice weekly, while as regards to the dose of FIX concentrate delivered, 50% of the centers reported administering prophylaxis once-weekly at a dose ranging from 5–100 IU/kg in 10–50% of HB patients. Thus, 93% of the centers reported using a dose of 25–50 IU/kg for twice-weekly prophylaxis in 6–100% of the patients. The majority of centers (86%) believe that, in a program of early primary prevention, once-weekly treatment with nonacog alfa may represent an alternative strategy to dose escalation. The results show that patients with mild hemophilia, with functional musculoskeletal status and difficulties with venous access, are candidates for once-weekly prophylaxis with nonacog alfa. For such patients, this regimen can improve treatment compliance and quality of life.

A Translational Study of TNF-Alpha Antagonists as an Adjunctive Therapy for Preventing Hemophilic Arthropathy

Repeated intra-articular hemorrhages lead to hemophilic arthropathy in severe hemophilia. Inflammation and pro-inflammatory cytokines (e.g., tumor necrosis factor alpha (TNFα)) might be involved in this pathogenesis. We hypothesized that anti-TNFα may provide adjuvant protection for hemophilic arthropathy management. We measured TNFα in synovial lavage from hemophilia mice subjected to hemarthrosis induction and synovial fluid from patients with hemophilic arthropathy (n = 5). In hemophilia mice, recurrent hemarthroses were induced, anti-TNFα was initiated either from day (D)7 after one hemarthrosis episode or D21 after three hemarthroses episodes (n ≥ 7/treatment group). In patients with hemophilic arthropathy (16 patients with 17 affected joints), a single dose of anti-TNFα was administered intra-articularly. Efficacy, characterized by synovial membrane thickness and vascularity, was determined. Elevated TNFα in synovial lavage was found in the hemophilia mice and patients with hemophilic arthropathy. Hemophilia mice subjected to three hemarthroses developed severe synovitis (Synovitis score of 6.0 ± 1.6). Factor IX (FIX) replacement alone partially improved the pathological changes (Synovitis score of 4.2 ± 0.8). However, anti-TNFα treatment initiated at D7, not D21, significantly provided protection (Synovitis score of 1.8 ± 0.9 vs. 3.9 ± 0.3). In patients with hemophilic arthropathy, intra-articular anti-TNFα significantly decreased synovial thickness and vascularity during the observed period from D7 to D30. Collectively, this preliminary study seems to indicate that TNFα may be associated with the pathogenicity of hemophilic arthropathy and anti-TNFα could provide adjuvant protection against hemophilic arthropathy. Further studies are required to confirm the preliminary results shown in this study.

Adherence to prophylactic treatment

: Prophylaxis has helped improve patients' perception of their quality of life, enabling them to lead a more normal life. For these reasons prophylactic treatment is nowadays considered a gold standard in the treatment of severe hemophilia A or B. Despite its benefits in terms of preventing bleeding and preserving patients' health, this intensive treatment is not always adhered to by patients with hemophilia - promotion of adherence should involve a multidisciplinary team which addresses not only the clinical aspects of a condition but also the different psychosocial aspects affecting patients and their (social, family and healthcare) environment.

Low Dose Prophylaxis in Hemophilia Care

Hemophilia is an inherited bleeding disorder which causes impaired blood clotting. The severity of disease depends on the type of Hemophilia, level of clotting factor concentrate (CFC), phenotypic heterogeneity and the development of inhibitors. The currently accepted standard of care of this disease is prophylaxis therapy (PT) with CFC. Prophylaxis therapy for Hemophilia is given in developed countries for the last few decades. On the contrary, episodic therapy (ET) is still the mode of treatment in middle and low income countries. ET is documented to have several potential risks such as increased bleeding rate, disability due to haemarthrosis, poor quality of life and increased chances of mortality. Several studies conducted in developed countries have confirmed the clinical efficacy of PT in Hemophilia treatment. Currently, there exist several challenges for implementation of this effective treatment in resource poor nations. Low dose prophylaxis (LDP) has been developed as a solution to minimize these challenges and to provide better care for subjects with Hemophilia from low resource countries. The impact of LDP was evaluated by several recent studies and the reported clinical outcomes seem to suggest an optimistic future for this line of therapy. Several themes related to Hemophilia care like inhibitor development, tolerance, pharmacokinetics of CFCs and cost-benefit analysis of different prophylaxis regimens are currently understood poorly. These distinct elements are highly relevant to assess the actual benefits of LDP regimen in a global scale.

Timely and large dose of clotting factor IX provides better joint wound healing after hemarthrosis in hemophilia B mice

Bleeding into the joints represents the major morbidity of severe hemophilia and predisposes it to hemophilic arthropathy (HA). In a reproducible hemarthrosis mouse model, we found distinct changes in thrombin activity in joint tissue homogenate following exposure of the joint to blood in wide type (WT) and hemophilic B mice. Specifically, at early time points (4 h and 24 h) after hemarthrosis, thrombin activity in WT mice quickly peaked at 4 h, and returned to baseline after 1 week. In hemophilia B mice, there was no/minimal thrombin activity in joint tissues at 4 h and 24 h, whereas at 72 h and thereafter, thrombin activity kept rising, and persisted at a higher level. Nevertheless, prothrombin had not decreased in both WT and hemophilia. The pattern was also confirmed by Western blotting and immunostaining. To optimize the protection against development of HA, we tested different treatment regimens by administration of clotting factor IX into hemophilia B mouse after hemarthrosis induction, including a total of 600 IU/kg FIX within the first 24 h or the whole 2-week period. We concluded that timely (in the first 24 h) and sufficient hemostasis correction is critical for a better protection against the development of hemophilic arthropathy.

Sports participation and physical activity in adult Dutch and Swedish patients with severe haemophilia: A comparison between intermediate- and high-dose prophylaxis

Introduction

Differences in treatment and outcome have been reported for persons with haemophilia (PWH) on intermediate‐dose (Dutch) and high‐dose (Swedish) prophylaxis, but the potential influence of sports participation has not been considered.

Aim

To compare sports participation and clinical outcome between adult Dutch and Swedish PWH.

Methods

Self‐reported sports participation (type and frequency per week), physical functioning (SF‐36_PF: 100‐0), joint status (HJHS: 0‐144), perceived limitations (HAL_sum: 100‐0) and physical activity (IPAQ) were recorded. Sports were classified according to National Haemophilia Foundation classification (5 categories, highest two were classified as high‐risk sports). Sports participation and clinical outcome were compared according to country and age (18‐22, 23‐29, 30‐40 years) using non‐parametric tests and Spearman correlations (rho).

Results

Seventy‐one adult PWH (NL: 43, SWE: 28) completed sports questionnaires (mean age: 26 years). All participants engaged in sports, including 59.2% in high‐risk sports (33.9% twice weekly). Dutch PWH showed a significant age‐related decline in (high‐risk) sports participation (7x/wk in PWH 18‐22 years to 2x/wk in PWH 30‐40 years, P < 0.05), joint health (HJHS: median 2‐15.5, P < 0.01) and physical functioning (SF‐36_PF: median 100 to 77.5, P < 0.01), while Swedish did not. Sports participation was not associated with bleeding (Spearman's rho = −0.119).

Conclusion

All participants reported sports participation, including 59.2% in high‐risk sports. Dutch PWH treated with intermediate‐dose prophylaxis showed an age‐related decline in sports participation, joint status and physical functioning, whereas Swedish PWH on high‐dose prophylaxis did not. Sports participation was not associated with bleeding.

Pharmacokinetic Studies of Factor VIII in Chinese Boys with Severe Hemophilia A: A Single-Center Study

Background:

Although much attention has been paid to the pharmacokinetics (PKs) of different factor VIII (FVIII) concentrates in persons with hemophilia A (HA), limited information is available in young boys with severe HA. In this study, we aimed to assess the PK parameters of FVIII products in boys with severe HA in China.

Methods:

A total of 36 boys (plasma-derived [pd]-FVIII, n = 15; recombinant [r] FVIII, n = 21) were enrolled between January 2015 and May 2016 in Beijing Children's Hospital. PK characteristics of FVIII products were studied according to a reduced 4-sampling time point design (1 h, 9 h, 24 h, and 48 h postinfusion).

Results:

The mean FVIII half-life (t_1/2) was 10.99 ± 3.45 h (range 5.52–20.02 h), the mean in vivo recovery (IVR) was 2.01 ± 0.42 IU/dl per IU/kg (range 1.24–3.02 IU/dl per IU/kg) and mean clearance (CL) of FVIII is 4.34 ± 1.58 ml·kg⁻¹·h⁻¹ (range 2.29–7.90 ml·kg⁻¹·h⁻¹). We also analyzed the influence of several parameters that potentially modulate FVIII PK. The age was closely associated with FVIII half-life (R²= 0.32, P < 0.01). The t_1/2 of FVIII increased by 0.59 h per year. Besides age, von Willebrand factor antigen (VWF:Ag) also was associated with FVIII half-life (R²= 0.52, P < 0.01). Patients with blood Group O had a shorter FVIII half-life than patients with non-O blood group (9.40 ± 0.68 h vs. 12.3 ± 0.79 h, t = 2.70, P = 0.01). The FVIII IVR correlated with age (R²= 0.21, P < 0.01) and VWF:Ag level (R²= 0.28, P < 0.01). CL rates were faster in young patients and in those with low-VWF:Ag levels. CL rates of FVIII are higher in blood Group O versus non-blood Group O persons (5.02 ± 0.38 vs. 4.00 ± 0.32 ml·kg⁻¹·h⁻¹, t = 2.53, P = 0.02).

Conclusions:

Chinese boys with severe HA have similar PK values to other ethnic groups and large differences in FVIII PK between individual patients. Age, blood group, and VWF:Ag levels are important determining factors for FVIII CL.

Joint Mobility and Physical Function of Danish Hemophilia Patients: A Three-Wave Panel Study Spanning 24 Years

BACKGROUND

The positive effects of factor treatment of hemophilia are well established, but the long-term outcomes are not well documented. This panel study evaluated changes in bleeding frequency, joint mobility, physical function, and symptoms in Danish patients with moderate to severe hemophilia A or B over 24 years.

METHODS

Three anonymous surveys were conducted in 1988, 2001, and 2012 targeting Danish patients with moderate to severe hemophilia, and the study participants, respectively, were 128, 156, and 164 male patients with hemophilia (PWH). The number of bleeding episodes, the use of factor concentrate, comorbidities, joint mobility, physical function, and symptoms were evaluated by means of self-reporting. Trends over time were analyzed using ordinal and multinomial logistic-regression models controlling for age group.

RESULTS

The proportion of PWH in the oldest age group (55-88 years) increased from 4% in 1988 to 18% in 2012. In 1988, a high risk of bleeding episodes was primarily found in the age group of 16-34 years. In 2012, a high risk was primarily found in the age group of 35-54 years. Joint mobility and physical function increased significantly from 1988 to 2012 but showed a noticeable decrement in the older age groups, even in 2012. Pain in the extremities, anxiety, and depression decreased significantly, but back pain increased. No significant changes were found for 7 other symptoms.

CONCLUSIONS

Significant improvements in joint mobility and physical function have occurred over the last 24 years, but PWH > 35 years still experience a decline in these areas with age. This decline underscores the importance of life-long treatment and continuous rehabilitation of PWH.

Investigating the relationship between the HJHS and HAL in routine clinical practice: A retrospective review

INTRODUCTION

Comprehensive musculoskeletal assessment for monitoring joint health in haemophilia includes both physical assessment with Haemophilia Joint Health Score (HJHS) and assessment of self-reported function by Haemophilia Activities List (HAL).

METHODS

Correlation between physical assessment and joint function was undertaken between HJHS and HAL in patients with SHA and SHB who had both assessments at the same visit over a one-year period.

RESULTS

Data from 120 patients (96-SHA/24 = SHB) with a median age 33 years (range 19-73) were included. Median total HJHS was 19, increasing with age: 18-30 years-7, 31-50 years-25 and 51-73 years-44. Similarly, median total HAL score was 80 with decreased function associated with increasing age: 18-30 years-90.4, 31-59 years-71.7, 51-73 years-49.5. Median Total HJHS and HAL demonstrated strong correlation (r_s  = 0.66, P < 0.01). Moderate-to-strong correlations were seen across the entire age group between the HJHS LL and UL subtotals and corresponding limb HAL domains. Within age groups, correlations were less significant particularly for the upper UL domains in HAL and the UL HJHS score. The wide range of ROM in joints categorized as markedly affected (ie, ROM loss score = 3) highlights the potential ceiling effect of this domain score and its use in chronically damaged joints.

CONCLUSION

HJHS and HAL showed moderate-to-strong correlation with discrepancy in some individual patients. Prospective studies are required to better understand the clinical utility of both especially in severe joint disease where HAL may have a potential advantage.

Optimizing bleed prevention throughout the lifespan: Womb to Tomb

The focus of care providers, patients and families is the ability to tailor care for persons with haemophilia (PWH) across the lifespan. Care requires knowledge of the bleeding disorder and age-related complications, risk of therapeutic interventions, and evaluation of individual characteristics that contribute to outcomes. The ultimate goal is to live a normal life without the burden of bleeding, for PWH and carriers. A wide range of therapeutic options is required to achieve personalized care. Over the last decade, substantial therapeutic advantages have been achieved in the treatment of haemophilia that include the development of a robust array of factor concentrates, novel haemostatic agents, and increased knowledge and awareness of disease associated outcomes and risk factors. Significant strides on the road to accessible gene therapy have been realized. This increased range of therapeutic modalities provides options for development and implementation of care plans for each patient at each stage of life that are more flexible compared to prior care regimens. Paradigms for management of haemophilia are changing. As a community, we must work together to use these resources wisely, to learn from outcomes with new therapies and diagnostic tools, to assure all patients can achieve improved care and outcomes regardless of disease state or country of origin.

Joint disease in haemophilia: Pathophysiology, pain and imaging

Haemarthroses cause major morbidity in patients with haemophilia. Blood has devastating effects on all joint components, resulting in synovitis, osteochondral degeneration and ultimately end-stage haemophilic arthropathy. Key players in this process are iron and inflammation. Preventing joint bleeds is of utmost importance to maintain joint health as targeted therapies directed against blood-induced inflammation and iron-mediated processes are lacking. Joint bleeds result in acute pain as well as chronic pain due to synovitis or arthropathy. Acute pain originates from nociceptors activated by tissue damage. In chronic inflammation, central and peripheral sensitization of nociceptors might occur resulting in chronic pain. This also triggers a series of brain disorders such as emotional fear, anxiety, mood depression and impairment of cognitive functions. Treatment of haemophilia-related pain not only consists of analgesics, but also of exercise, education and in selected cases antidepressants and anticonvulsants. For objective assessment of joint structural outcome and detecting earlier changes of haemophilic arthropathy, both ultrasound (US) and magnetic resonance (MR) imaging have shown valuable. Both can be considered equally able to reveal signs of disease activity. MR imaging is able to visualize haemosiderin deposition and is more comprehensive in depicting osteochondral changes. Disadvantages of MR imaging are the duration of the examination, evaluation of a single joint at a time, costs and may require sedation, and it may need intraarticular contrast injection to depict initial osteochondral changes with accuracy. As such, US is a more useful screening tool and can be used for repeated follow-up examinations.

[Efficacy of short-term full-dose prophylaxis in adult Chinese patients with severe hemophilia A]

OBJECTIVE

To investigate the efficacy of short-term full-dose prophylaxis in adult Chinese patients with severe hemophilia A.

METHODS

Thirteen adult Chinese patients with severe hemophilia A receiving on-demand or low-dose prophylaxis underwent ultrasound examination of the target joints and evaluation of Hemophilia Joint Health Score (HJHS). The data of annual bleeding episodes in the period of on-demand or low-dose prophylaxis were collected retrospectively from the patients, and the changes in bleeding and joint condition (ultrasound findings of the target joints and HJHS) were observed during short-term full-dose prophylaxis. The activity intensity of the patients was assessed using the IPAQ questionnaire, and the 72 h FⅧ trough activity was measured during full-dose prophylaxis.

RESULTS

The median age of the 13 patients was 26.0 (20.5-29.0) years. For full-dose prophylaxis, the patients received a median therapeutic dose of 31.0 (29.1-33.0) IU/kg, administered for 3 times per week; the median 72 h FⅧ trough activity of patients was 1.7% (1.3-3.4%). During the follow-up period for 3 months, the annual bleeding rates (ABR) and annual joint bleeding rates (AJBR) decreased significantly in all the patients (P=0.001 and 0.001, respectively), but zero bleeding was achieved in only 4 patients (30.8%) and zero joint bleeding in 7 patients (53.8%); 9 patients (69.2%) still experienced breakthrough bleeding. The damage severity of target joints assessed by ultrasound and HJHS in 6 patients (46.2%)was worse than before and no obvious progression of target joints damage was found in 7 patients (53.8%). Compared with the patients without progression, the patients with worsened joint damage had poorer baseline joint condition, higher bleeding frequencies before and during the follow-up, a higher intensity of physical activity, and a lower baseline FⅧ activity.

CONCLUSIONS

At present, although short-term full-dose prophylaxis can significantly reduce the bleeding and partially prevent the progression of joint damage, it is not yet possible to achieve the goal of zero bleeding for all adult patients with severe hemophilia A in China, nor can it completely prevent further joint damage. For adult patients with different clinical bleeding phenotypes, joint conditions and physical activity intensity, individualized therapy involving additional evaluation methods should be implemented, and physiotherapy and surgical intervention can be considered when necessary.

The Impact of Bleeding Disorders on the Socioeconomic Status of Adult Patients

The impact of inherited bleeding disorders on the socioeconomic status (SES) of affected individuals is not clear. The SES of adult patients with congenital bleeding disorders (PWBD) from a centre in Germany (age 42.3 ± 15.0 years) was compared to that of a gender- and age-matched control group of patients with thrombophilia or a thrombotic event (PWT). Patients completed a questionnaire including aspects of SES, impact of the disease on their lives, and health-related quality of life (HRQoL). Forty-five patients were enrolled in each group; 71 % of PBWD had a severe form of the bleeding disorder (FVIII/IX activity < 1 % or VWD type 3), and 60 % of all PWBD were treated on-demand. PWBD had a lower monthly income (p = 0.029) and a worse occupational status (p = 0.047) than PWT, but there was no difference regarding the project-specific SES index. PWBD also reported a worse HRQoL in the physical summary component score of the SF-36 (p < 0.001). More PWBD (69.8 %) reported a high impact of the disease on their lives than PWT (33.3 %, p < 0.001). In summary, PWBD had a worse occupational status, monthly income, health behaviour, HRQoL, and impact of the disease on their lives compared to PWT, but not a significantly different SES in general.

Blood-induced bone loss in murine hemophilic arthropathy is prevented by blocking the iRhom2/ADAM17/TNF-α pathway

Hemophilic arthropathy (HA) is a debilitating degenerative joint disease that is a major manifestation of the bleeding disorder hemophilia A. HA typically begins with hemophilic synovitis that resembles inflammatory arthritides, such as rheumatoid arthritis, and frequently results in bone loss in patients. A major cause of rheumatoid arthritis is inappropriate release of the proinflammatory cytokine tumor necrosis factor-α (TNF-α) by the TNF-α convertase (TACE; also referred to as ADAM17) and its regulator, iRhom2. Therefore, we hypothesized that iRhom2/ADAM17-dependent shedding of TNF-α also has a pivotal role in mediating HA. Here, we show that addition of blood or its components to macrophages activates iRhom2/ADAM17-dependent TNF-α shedding, providing the premise to study the activation of this pathway by blood in the joint in vivo. For this, we turned to hemophilic FVIII-deficient mice (F8-/- mice), which develop a hemarthrosis following needle puncture injury with synovial inflammation and significant osteopenia adjacent to the affected joint. We found that needle puncture-induced bleeding leads to increased TNF-α levels in the affected joint of F8-/- mice. Moreover, inactivation of TNF-α or iRhom2 in F8-/- mice reduced the osteopenia and synovial inflammation that develops in this mouse model for HA. Taken together, our results suggest that blood entering the joint activates the iRhom2/ADAM17/TNF-α pathway, thereby contributing to osteopenia and synovitis in mice. Therefore, this proinflammatory signaling pathway could emerge as an attractive new target to prevent osteoporosis and joint damage in HA patients.

Focusing in on use of pharmacokinetic profiles in routine hemophilia care

BACKGROUND

Emergence of population pharmacokinetic models for prediction of individual pharmacokinetic (PK) profiles facilitates individualization of prescribed prophylactic therapy for patients with hemophilia A and B and may have a favorable impact on clinical outcomes and annual factor utilization. How providers approach the integration and application of these data into routine clinical practice is not clear.

OBJECTIVE

To explore the potential application of and barriers to incorporating PK profiles into current hemophilia prophylaxis decision making.

METHODS

A facilitated group discussion of hematologists practicing within the federally-supported United States Hemophilia Treatment Center Network was conducted. Separately, a group of parents of patients with severe hemophilia less than 18 years of age participated in a focus group on individualizing prophylactic factor regimens with the use of PK data.

RESULTS

Physician participants constructed a conceptual model for factors that determined their selection of hemophilia prophylaxis. These factors clustered in five groupings. When charged with creating a prophylaxis regimen for a specific clinical case including PK data, eight of nine providers generated a unique regimen. Parent focus group supported PK data use as they preferred data driven treatment decisions.

CONCLUSIONS

Clinician application of PK data for prophylaxis decision making is heterogeneous. Prospective evaluation of the use of PK-tailored prophylaxis in routine care and its impact on patient outcomes is needed. Parents perceived that, while obtaining blood draws could be challenging, images of factor activity decay informed their decisions about physical activity timing and provided an opportunity for partnership and shared decision making with their provider.

Evolving Complexity in Hemophilia Management

Rapid expansion of therapeutic options have increased the complexity of hemophilia care. Previously, on-demand therapy aimed to reduce morbidity and early mortality; however, now aggressive prophylaxis, particularly in children, encourages an active lifestyle. Accurate diagnosis, recognition of early threats to musculoskeletal health, and optimization of therapy are critical for both males and females affected by hemophilia. The diversity of emerging hemophilia therapies, from modified factor protein concentrates, to gene therapy, to nonfactor hemostatic strategies, provide an exciting opportunity to target unmet needs in the bleeding disorder community.

Tailored frequency-escalated primary prophylaxis for severe haemophilia A: results of the 16-year Canadian Hemophilia Prophylaxis Study longitudinal cohort

BACKGROUND

Severe haemophilia A has high morbidity, and treatment, while effective, is very expensive. We report the 16-year follow-up of the Canadian Hemophilia Prophylaxis Study, which examined the effectiveness of tailored frequency-escalated primary prophylaxis with a focus on health outcomes within the domains of body structures and functions, and activities and participation (according to the WHO International Classification of Functioning, Disability and Health [WHO-ICF] framework) and a view to reducing consumption of costly clotting factor, which accounts for more than 90% of the cost of care of severe haemophilia.

METHODS

In this longitudinal study, boys with severe haemophilia A from 12 Canadian centres were enrolled at age 1·0-2·5 years. They were treated with standard half-life recombinant factor VIII (SHL-rFVIII), beginning as once-weekly prophylaxis with 50 IU/kg and escalating in frequency (with accompanying dose adjustments) in response to breakthrough bleeding as determined by the protocol. The primary endpoint for this analysis was joint health, as measured by the modified Colorado Child Physical Examination Scores (CCPES) at study end. All analyses were done by intention to treat. The trial is complete, and is registered with ClinicalTrials.gov, number NCT01085344.

FINDINGS

Between June 26, 1997, and Jan 30, 2007, 56 boys were enrolled. They were followed for a median of 10·2 years (to a maximum of 16·1 years). Median rFVIII usage was about 3600 IU/kg per year. The median end-of-study CCPES physical examination score was 1 (IQR 1-3; range 0-12) for the left ankle and 1 (1-2; 0-12) for the right ankle, with all other joints having a median score of 0. No treatment-related safety events occurred over the duration of the study, including central venous catheter infections. The median annualised index joint bleeding rate was 0·95 per year (IQR 0·44-1·35; range 0·00-13·43), but 17 (30%) patients had protocol-defined unacceptable breakthrough bleeding at some point during the study.

INTERPRETATION

Tailored frequency-escalated prophylaxis leads to very little arthropathy and very good health outcomes within the WHO-ICF domains, and only uses a moderate amount of expensive clotting factor as compared with standard prophylaxis protocols. Some sequelae of bleeding were observed in our cohort, and future studies should consider a more stringent protocol of escalation.

FUNDING

This study was initially funded by grants from the Medical Research Council of Canada/Pharmaceutical Manufacturers Association of Canada Partnership Fund and the Bayer/Canadian Blood Services/Hema-Quebec Partnership Fund. Subsequent renewals were funded by Bayer.

Hémophilie : la thérapie génique, enfin…

Recent efforts at gene therapy for haemophilia A and B using AAV-derived vectors show durable expression of coagulation factors at significant levels, resulting in almost complete correction of the phenotype. This is the first success of gene therapy for a major hereditary disorder, and shows how continuous improvement of many components of the system has finally succeeded. Although these results must be confirmed with more patients and longer durations, they constitute a significant accomplishment for this approach after decades of frustration.

Sociodemographic, Clinical, and Psychosocial Characteristics of People with Hemophilia in Portugal: Findings from the First National Survey

Hemophilia is a rare genetic bleeding disorder associated with pain, impaired functionality, and decreased quality of life (QoL). Several studies have focused on patient-reported outcomes of people with hemophilia (PWH) worldwide, but no such data are available for Portugal. This survey aimed to describe sociodemographic, clinical, and psychosocial characteristics of PWH of all ages in Portugal. Questionnaires were answered by self-report or by parents of children with hemophilia (proxy version). Variables assessed were sociodemographic and clinical, physical activity patterns, pain, functionality (HAL/PedHAL), QoL (A36 Hemofilia-QoL/CHO-KLAT), anxiety and depression (PROMIS), and illness perceptions (IPQ-R). One-hundred and forty-six PWH answered the survey: 106 adults, 21 children/teenagers between 10 and 17 years, 11 children between 6 and 9 years, and 8 children between 1 and 5 years. Most participants had severe hemophilia (60.3%) and type A was most commonly reported (86.3%). Bleeding episodes, joint deterioration, and pain were very prevalent, with the ankles and knees being the most affected joints, as illustrated by HAL/PedHAL scores. The A36 Hemofilia-QoL assessment showed moderate QoL (96.45; 0–144 scale) and significant anxiety and depression symptoms were found in 36.7 and 27.2% of adults, respectively. CHO-KLAT global score (0–100 scale) was 75.63/76.32 (self-report/proxy). Concerning hemophilia-related illness beliefs, a perception of chronicity and symptoms unpredictability was particularly prominent among adults and children/teenagers. This survey provided a comprehensive characterization of Portuguese PWH, including the first report of psychosocial characteristics. The findings allow for a deeper understanding of life with hemophilia in Portugal and the identification of relevant health care and research needs.

The endothelial specific isoform of type XVIII collagen correlates to annual bleeding rate in haemophilia patients

Introduction

The medical need in the haemophilic (HF) field to reduce bleeding incidents requires measurement of the annual bleeding rate (ABR) in haemophiliacs. Vascular rupture is associated with damage to the vascular endothelium causing exposure of the basement membrane. Endothelial cells and matrix impairment may be associated with joint bleeds and later development of HF arthropathy. Imbalanced extracellular matrix turnover is a central pathological feature in many diseases consequent to epithelial or endothelial cell damage. Type XVIII collagen is an essential basement membrane component, with an endothelial specific isoform.

Aim

To quantify the basement membrane specifically for the endothelial cells, as that may have particular relevance to endothelial cell stability and rupture in haemophiliacs. A newly developed ELISA assay detecting endothelial type XVIII collagen (COL-18N) was used to assess the clinical relevance of endothelial basement membrane turnover in patients diagnosed with HF arthropathy and correlation to ABR.

Methods

We developed an ELISA assay for quantification of COL-18N. Serum from 35 male HF patients was investigated using the COL-18N ELISA.

Results

COL-18N correlated to the ABR of haemophiliacs, r = 0.45, P<0.006.

Conclusion

Vascular rupture and consequent bleeding are associated with joint damage and deterioration of life quality in haemophiliacs. Quantification of ABR is an important part in efficacy assessment of different interventions, and the benchmark of these. Objective biomarkers reflecting endothelial dysfunction, vascular leaks and rupture, like the COL-18N biomarker that associate with ABR, may assist in identifying the most optimal treatment and monitoring of HF patients.

Categorizing factors of adherence to parenteral treatment in growth hormone deficiencies and hemophilia: What should be the targets for future research?

Adherence to treatment regimens in growth hormone dysregulations and hemophilia is related to better outcome and fewer complications over time. Subcutaneous growth hormone injection and intravenous blood factor replacement therapies are parenteral treatments with a comparable regimen calling for similar behavioral processes. Although we have lists of possible factors influencing adherence in these conditions, the evidence is scattered. The objective of this study was to systematically review empirical studies linking factors of adherence with measures of adherence. To categorize the factors, we used a taxonomy from the diabetes literature. We used four major electronic databases to identify articles. We synthesized 27 articles dated 2011-2017 corresponding to inclusion criteria. Results showed a consistent proportion of 20%-25% participants with adherent issues. Strong arguments pointed to the transition to self-care in pediatrics as a vulnerability period (7/27 reports). We found the domains of individual factors (<30% reports), relational factors (<13%), health care (<30%), to be understudied in comparison with that of demographic or clinical context (>74%), and practical issues (>37%). The results suggest that future research should focus on modifiable factors of adherence, with appropriate measurement and intervention strategies. One central methodological limitation of reviewed reports was the lack of longitudinal designs, and the quasi absence of behavioral trial targeting modifiable factors of adherence. A new research agenda should be set in these rare diseases as higher adherence should translate into improved outcome and better quality of life for patients and their families.

Using pharmacokinetics to individualize hemophilia therapy

Prevention and treatment of bleeding in hemophilia requires that plasma clotting factor activity of the replaced factor exceeds a defined target level. Most clinical decisions in hemophilia are based on implicit or explicit application of pharmacokinetic measures. The large interindividual variability in pharmacokinetics of factor concentrates suggests that relying on the average pharmacokinetic characteristics of factor concentrates would not allow optimizing the treatment of individual patients; for example, adjusting the frequency of infusions and targeting a specific clotting factor activity level on a case-by-case basis. However, individual pharmacokinetic profiles are seldom assessed as part of routine clinical care. Population pharmacokinetics provide options for precise and convenient characterization of pharmacokinetics characteristics of factor concentrates, simplified individual pharmacokinetic profiling, and individualized dosing. Population pharmacokinetics allow for the incorporation of determinants of interpatient variability and reduces the need for extensive postinfusion plasma sampling. Barriers to the implementation of population pharmacokinetics are the need for concentrate-specific pharmacokinetic models, Bayesian calculation power, and specific expertise for production, validation, and appraisal of forecasted estimates. Population pharmacokinetics provide an important theoretical and practical contribution to tailoring the treatment of hemophilia. The need remains for prospective exploration of the clinical impact of tailoring hemophilia treatment based on individual pharmacokinetics, and for the systematic validation of existing software solutions and concentrate-specific models.

Practical considerations in choosing a factor VIII prophylaxis regimen: Role of clinical phenotype and trough levels

Current therapy for haemophilia A is guided by severity of the disease, which in turn is best reflected in patients' endogenous factor VIII activity levels. For patients with severe haemophilia (particularly children), prophylaxis with continuous routine factor replacement has become standard of care in developed countries and is gradually becoming the standard of care in developing countries. The question arises then: what is an appropriate prophylaxis regimen to prevent bleeding events and arthropathy, while also maximizing patient quality of life and taking into consideration the costs of prophylaxis? Should all patients be treated with one standard, fixed prophylaxis regimen, or should prophylaxis be individualised for each patient? If so, what factors need to be considered in choosing the appropriate dose and frequency of factor administration? If prophylaxis is tailored to the individual patient, then patient-related factors (bleeding phenotype, activity profiles, age, joint status) and product-specific factors (half-life of the replacement factor in the individual patient) will determine the choice of regimen, whether it be a fixed-regimen prophylaxis or prophylaxis that is tailored to patient activity and bleeding risk. Regardless of the choice of prophylaxis regimen, for any regimen to be effective, adherence to therapy is key to optimising outcomes.

Improved joint health in subjects with severe haemophilia A treated prophylactically with recombinant factor VIII Fc fusion protein

INTRODUCTION

Joint arthropathy is the long-term consequence of joint bleeding in people with severe haemophilia.

AIM

This study assessed change in joint health over time in subjects receiving recombinant factor VIII Fc fusion protein (rFVIIIFc) prophylaxis.

METHODS

ALONG is the phase 3 pivotal study in which the benefit of rFVIIIFc as a prophylactic treatment for bleeding control was shown in previously treated severe haemophilia patients ≥12 years of age (arm 1: 25-65 IU/kg every 3-5 days, arm 2: 65 IU/kg weekly and arm 3: episodic). After completing ALONG, subjects had the option to enrol into the extension study (ASPIRE). This interim, post hoc analysis assessed changes in joint health over ~2.8 years in these patients.

RESULTS

Forty-seven subjects had modified Haemophilia Joint Health Score (mHJHS) data at A-LONG baseline, ASPIRE baseline and ASPIRE Year 1 and Year 2. Compared with A-LONG baseline (23.4), mean improvement at ASPIRE Year 2 was -4.1 (95% confidence interval [CI], -6.5, -1.8; P = .001). Regardless of prestudy treatment regimen, subjects showed continuous improvement in mHJHS from A-LONG baseline through ASPIRE Year 2 (prestudy prophylaxis: -2.4, P = .09; prestudy episodic treatment: -7.2, P = .003). Benefits were seen in subjects with target joints (-5.6, P = .005) as well as those with severe arthropathy (-8.8, P = .02). The mHJHS components with the greatest improvement at ASPIRE Year 2 were swelling (-1.4, P = .008), range of motion (-1.1, P = .03) and strength (-0.8, P = .04).

CONCLUSIONS

Prophylaxis with rFVIIIFc may improve joint health over time regardless of prestudy prophylaxis or episodic treatment regimens.