Attempting to remedy sub-optimal medication adherence in haemophilia: The rationale for repeated ultrasound visualisations of the patient's joint status

Awareness of individual goals, preferences, and priorities of persons with severe congenital haemophilia A for a tailored shared decision-making approach to liver-directed gene therapy. A practical guideline

In clinical medicine, shared decision making (SDM) is a well-recognized strategy to enhance engagement of both patients and clinicians in medical decisions. The success of liver-directed gene therapy (GT) to transform severe congenital haemophilia A (HA) from an incurable to a curable disease has launched a shift beyond current standards of treatment. However, GT acceptance remains low in the community of HA persons. We argue for both persons with haemophilia (PWH) and specialists in HA care including clinicians, as needing SDM-oriented educational programs devoted to GT. Here, we provide an ad hoc outline to implement education to SDM and tailor clinician information on GT to individual PWHs. Based on routine key components of SDM: patient priorities; recommendations based on individual risk reduction; adverse effects; drug-drug interactions; alternatives to GT; and ongoing re-assessment of the objectives as risk factors (and individual priorities) change, this approach is finalized to exploit efficacious communication.

The hidden joint in children with haemophilia on prophylaxis

Prophylaxis is the gold standard treatment for children with haemophilia (CWH). MRI studies revealed joint damage, even with this treatment; this suggests the presence of subclinical bleeding. In the case of children with haemophilia, it is relevant to detect early signs of joint damage, as this allows the medical team to provide the appropriate treatment and follow-up, in order to avoid arthropathy development and its consequences. The aim of this study is to detect the hidden joint in children with haemophilia on prophylaxis (CWHP) and analyse, by age group, which joint is the most affected. We define the hidden joint in CWH on prophylaxis as the joint that presents joint damage secondary to repetitive bleeding episodes and is detected in the joint evaluation, despite being asymptomatic or with mild symptoms. It is most commonly caused by repetitive subclinical bleeding.

METHODS

This was an observational, analytical, cross-sectional study of 106 CWH on prophylaxis treated in our centre. Patients were divided according to age and type of treatment. Joint damage was defined as a HEAD-US score ≥ 1.

RESULTS

Patients' median age was 12 years. All had severe haemophilia. The median age of onset of prophylaxis was 2.7. Forty-seven (44.3 %) patients received primary prophylaxis (PP) and 59 (55.7 %), secondary prophylaxis. Six hundred and thirty-six joints were analysed. Type of prophylaxis and joint involvement showed statistically significant differences (p < 0.001). However, patients on PP had a greater number of damaged joints at older ages. Twenty-two % (140) of the joints scored ≥1 on HEAD-US. Cartilage was most frequently involved, followed by synovitis, and bone damage. We observed a greater frequency and degree of arthropathy in subjects aged 11 and above. Sixty (12.7 %) joints showed a HEAD-US score ≥ 1, with no history of bleeding. The ankle was the most affected joint, representing the hidden joint according to our definition.

CONCLUSION

Prophylaxis is the best treatment for CWH. However, symptomatic or subclinical joint bleeding may occur. The routine evaluation of joint health is relevant, particularly, of the ankle. In our study, early signs of arthropathy according to age and type of prophylaxis were detected by HEAD-US.

The role of point-of-Care Musculoskeletal Ultrasound for Routine Joint evaluation and management in the Hemophilia Clinic - A Real World Experience

BACKGROUND

The use of musculoskeletal ultrasound (MSKUS) for point-of-care (POC) evaluation of hemophilic arthropathy is growing rapidly. However, the extent to which MSKUS influences clinical treatment decisions is unknown.

METHODS

We conducted a three-year, prospective, multi-center study at three hemophilia treatment centers in the United States to evaluate the utilization of POC-MSKUS for routine clinical decision-making in adult persons with hemophilic arthropathy. Bilateral elbows, knees and ankles were assessed clinically [Hemophilia Joint Health Score (HJHS)] and with POC-MSKUS by the Joint _TissueActivity and Damage Exam (JADE) protocol at baseline and approximately annually for two additional times. Treatment decisions, including physical therapy (PT) and "medical" (joint injections/aspirations, referrals to orthopedics, changes/adjustments of hemostatic plans, and use of oral anti-inflammatory medications) were recorded in relation to POC-MSKUS.

RESULTS

Forty-four persons [median age 37 years (IQR 29, 51)], mostly with severe Hemophilia A on clotting factor prophylaxis, completed 129 visits, yielding 792 joint exams by POC-MSKUS and HJHS [median at baseline 27 (IQR 18, 42)] over a median follow up of 584 days (range: 363 to 1072). Among 157 management decisions, 70% were related to PT plans (n = 110) and 30% were "medical". Point-of-care MSKUS influenced 47/110 (43%) PT plans, mostly informing treatment of specific arthropathic joints (45/47 plans) in patients with high HJHS. Physical therapy plans influenced by POC-MSKUS directed more manual therapy/therapeutic exercises, while plans based on physical exam were focused more on global exercises and wellness. Treatment decisions were mostly based on the identification of specific musculoskeletal abnormalities visualized by POC-MSKUS. Of note 20/47 (43%) POC-MSKUS plans included de-escalation strategies, thereby reducing exercise intensity, mostly for joint instability and subclinical hemarthroses. Point-of-care MSKUS also informed 68% (32/47) of "medical" decisions, surprisingly mostly for injections/aspirations and referrals to orthopedics, and not for adjustments of hemostatic treatment. Although not formally studied, ultrasound images were used frequently for patient education.

CONCLUSION

Routine joint evaluations with POC-MSKUS resulted in few changes regarding medical management decisions but had a profound effect on the formulation of PT plans. Based on these findings, new studies are essential to determine the benefit of MSKUS-informed management plans on joint health outcomes.

Impact of the HEAD-US Scoring System for Observing the Protective Effect of Prophylaxis in Hemophilia Patients: A Prospective, Multicenter, Observational Study

Objective:

This study aimed to observe the preventive effect of prophylactic treatment on joint health in people with hemophilia (PwH) and to investigate the importance of integration of ultrasonographic examination into clinical and radiological evaluation of the joints.

Materials and Methods:

This national, multicenter, prospective, observational study included male patients aged ≥6 years with the diagnosis of moderate or severe hemophilia A or B from 8 centers across Turkey between January 2017 and March 2019. Patients were followed for 1 year with 5 visits (baseline and 3^rd, 6^th, 9^th, and 12^th month visits). The Hemophilia Joint Health Score (HJHS) was used for physical examination of joints, the Pettersson scoring system was used for radiological assessment, point-of-care (POC) ultrasonography was used for bilateral examinations of joints, and the Hemophilia Early Arthropathy Detection with Ultrasound (HEAD-US) score was used for evaluation of ultrasonography results.

Results:

Seventy-three PwH, of whom 62 had hemophilia A and 11 had hemophilia B, were included and 24.7% had target joints at baseline. The HJHS and HEAD-US scores were significantly increased at the 12^th month in all patients. These scores were also higher in the hemophilia A subgroup than the hemophilia B subgroup. However, in the childhood group, the increment of scores was not significant. The HEAD-US total score was significantly correlated with both the HJHS total score and Pettersson total score at baseline and at the 12^th month.

Conclusion:

The HEAD-US and HJHS scoring systems are valuable tools during follow-up examinations of PwH and they complement each other. We suggest that POC ultrasonographic evaluation and the HEAD-US scoring system may be integrated into differential diagnosis of bleeding and long-term monitoring for joint health as a routine procedure.

Perspective - The case for zero bleeds and drug bioequivalence in the treatment of congenital hemophilia A in 2021

Not all patients with severe hemophilia A (HA) respond optimally to a given dose of a given product. Within-individual variance in cross-over studies makes each patient unique in the response to each standard half-life (SHL) factor VIII (FVIII) product in pharmacokinetic (PK) terms. This hampers the prediction of efficacy when a SHL FVIII product is employed. PK data showing that half-lives of SHL rFVIII are unsatisfactory to achieve zero bleeding in individual HA patients provide the rationale for switching from SHL to extended half-life (EHL) products. However, not all subjects receiving prophylaxis with EHL products achieve zero bleeding, the most cogent objective of personalized prophylaxis. Known determinants of FVIII half-life (age, von Willebrand factor [VWF] levels, blood group) cumulatively account for one third of the total inter-individual variation in FVIII clearance in subjects with severe HA. Investigations into precision, and accuracy of laboratory measurement to be employed; newer pathways for the clearance of both free-FVIII and VWF-bound FVIII, and adequately powered studies on omics and phenotypic heterogeneity, are likely to provide additional information on the remaining two thirds of inter-individual variation in FVIII clearance in HA. Variability in the clinical response has also been documented in patients when FVIII activity is mimicked by fixed subcutaneous doses of the bispecific antibody emicizumab. National registries that collect PK data of available FVIII products and ad hoc information on the individual response to emicizumab should be encouraged, to establish newer standards of care and ease personalized clinical decisions to achieve zero bleeding.

Clinical, humanistic, and economic burden of severe hemophilia B in the United States: Results from the CHESS US and CHESS US+ population surveys

BACKGROUND

Hemophilia B is a rare congenital bleeding disorder that has a significant negative impact on patients' functionality and health-related quality of life. The standard of care for severe hemophilia B in the United States is prophylactic factor IX replacement therapy, which incurs substantial costs for this lifelong condition. Accurate estimates of the burden of hemophilia B are important for population health management and policy decisions, but have only recently accounted for current management strategies. The 'Cost of Severe Hemophilia across the US: a Socioeconomic Survey' (CHESS US) is a cross-sectional database of medical record abstractions and physician-reported information, completed by hematologists and care providers. CHESS US+ is a complementary database of completed questionnaires from patients with hemophilia. Together, CHESS US and CHESS US+ provide contemporary, comprehensive information on the burden of severe hemophilia from the provider and patient perspectives. We used the CHESS US and CHESS US+ data to analyze the clinical, humanistic, and economic burden of hemophilia B for patients treated with factor IX prophylaxis between 2017 and 2019 in the US.

RESULTS

We conducted analysis to assess clinical burden and direct medical costs from 44 patient records in CHESS US, and of direct non-medical costs, indirect costs, and humanistic burden (using the EQ-5D-5L) from 57 patients in CHESS US+. The mean annual bleed rate was 1.73 (standard deviation, 1.39); approximately 9% of patients experienced a bleed-related hospitalization during the 12-month study period. Nearly all patients (85%) reported chronic pain, and the mean EQ-5D-5L utility value was 0.76 (0.24). The mean annual direct medical cost was $614,886, driven by factor IX treatment (mean annual cost, $611,971). Subgroup analyses showed mean annual costs of $397,491 and $788,491 for standard and extended half-life factor IX treatment, respectively. The mean annual non-medical direct costs and indirect costs of hemophilia B were $2,371 and $6,931.

CONCLUSIONS

This analysis of patient records and patient-reported outcomes from CHESS US and CHESS US+ provides updated information on the considerable clinical, humanistic, and economic burden of hemophilia B in the US. Substantial unmet needs remain to improve patient care with sustainable population health strategies.

The evolving landscape of gene therapy for congenital haemophilia: An unprecedented, problematic but promising opportunity for worldwide clinical studies

With liver-directed gene therapy, congenital haemophilia has the potential to progress from an incurable to a phenotypically curable condition. However, the proportion of haemophilia population likely to benefit from gene therapy remains to be established. Achieving a phenotypic curative goal is presently hampered by: 1) availability of effective treatments (e.g. extended half-life products, non-factor therapies) that address major unmet needs in haemophilia; 2) key differences between hope and reality that patients undergoing gene therapy face (e.g. unknown risks and long-term follow-up, durability of the therapeutic effect, possibility of re-administering the vector), 3) lack of expertise of health care professionals (HCP) in managing/monitoring unexpected side effects in patients, and 4) lack of expertise of HCP in advising payers on key issues for cost-effectiveness analyses of gene therapy (e.g., eligibility criteria, predictability of response, unknown risks, long-term complications). There is also uncertainty about the possibility to absorb the cost of the "one-time, one-dose cure" by payers that are used to different payment models. An active partnership between regulators, payers, patients and health care professionals is key to identify patient sub-populations that might benefit the most from gene therapy, and to align the interests of patients (needing effective disease correction and improved quality of life) and pharma companies (reluctant to lose the profitability of lifelong repeated treatments). Educational programs will provide the healthcare chain with information on the strategy that is expected to transform morbidity and mortality patterns and how it should be regarded as part of the future therapeutic options in haemophilia.

Long-term safety and efficacy of rIX-FP prophylaxis with extended dosing intervals up to 21 days in adults/adolescents with hemophilia B

BACKGROUND

An international, multicenter extension study evaluated recombinant fusion protein linking recombinant coagulation factor IX (FIX) with recombinant human albumin (rIX-FP) in hemophilia B (FIX ≤ 2%) patients previously enrolled in a phase III study or who initiated rIX-FP prophylaxis following surgery.

OBJECTIVES

To investigate the long-term safety and efficacy of rIX-FP prophylaxis in adult previously treated patients (PTPs) with hemophilia B.

METHODS

Male PTPs were treated with a 7- (35-50 IU/kg), 10- or 14-day regimen (50-75 IU/kg). Patients ≥18 years who were well-controlled on a 14-day regimen for ≥6 months could switch to a 21-day regimen (100 IU/kg).

RESULTS

A total of 59 patients (aged 13-63 years) participated in the study. Following a single dose of 100 IU/kg rIX-FP, in patients eligible for the 21-day regimen, the mean terminal half-life was 143.2 hours. Mean steady-state FIX trough activity levels ranged from 22% with the 7-day regimen to 7.6% with the 21-day regimen. Median (Q1, Q3) annualized spontaneous bleeding rates were 0.00 (0.00, 1.67), 0.28 (0.00, 1.10), 0.37 (0.00, 1.68), and 0.00 (0.00, 0.45) for the 7-, 10-, 14-, and 21-day regimens, respectively. Comparable efficacy was demonstrated for both the 14- and 21-day regimens compared to the 7-day regimen. Overall, 96.5% of bleeding episodes were treated successfully with 1 to 2 rIX-FP infusions. No patients developed an inhibitor and treatment was well tolerated.

CONCLUSIONS

rIX-FP extended interval prophylaxis provides dosing flexibility and, in selected patients, a 21-day regimen may provide an alternative option to minimize treatment burden and individualize treatment.

Paradigm shift for the treatment of hereditary haemophilia: Towards precision medicine

Patients with haemophilia A (HA) or B (HB) experience spontaneous limb- or life-threatening bleedings which are prevented by regular prophylactic intravenous infusions of the deficient coagulation factor (FVIII or FIX). Prophylaxis with subcutaneous long-acting non-factor products that improve in vivo thrombin generation is now under intensive investigation (concizumab, fitusiran) or successfully employed (emicizumab) in haemophilia patients. Both haemophilia patients with/without inhibitors take advantage of non-factor products employed alone. In those who also need bypassing agents (or FVIII concentrates) for breakthrough bleeds, thromboembolic events and/or thrombotic microangiopathy may occur. By enhancing thrombin generation, prothrombotic mutations co-segregating with FVIII/FIX gene mutations may trigger thrombotic episodes in HA patients carrying acquired thrombogenic factors (e.g. venous catheters). A thorough knowledge of individual needs increasingly contributed to improve comprehensive care and personalize treatments in haemophilia. Integrating genomics, lifestyle and environmental data is expected to be key to: 1) identify which haemophilia patients are less likely to benefit from a given intervention; 2) define optimal dosing and scheduling of bypassing agents (or FVIII) to employ in combination with non-factor products; 3) establish tests to monitor in vivo thrombin generation; 4) improve communication and deliver results to individuals. As individual outcomes will be improved and the risk of adverse events minimized, non-factor products will come into wider use within the haemophilia community, and patients will hopefully have no more risks of breakthrough bleeds. The risks of a normal life for a "former haemophilia patient" is likely to change the treatment landscape and the structure of haemophilia Centers.

Merging into the mainstream: the evolution of the role of point-of-care musculoskeletal ultrasound in hemophilia

Bleeding with resultant hemophilic arthropathy constitutes the largest cause of morbidity in patients with hemophilia. It results from repeated bleeding episodes in the joint and is characterized by synovial hypertrophy and cartilage and bony destruction. Hemophilic arthropathy assessment is a continually evolving process and is particularly challenging in children and young adults in whom joint disease may be missed or underestimated as obtaining serial "baseline" magnetic resonance imaging scans of multiple clinically asymptomatic or nearly asymptomatic joints may be unjustifiable and cost-ineffective. Musculoskeletal ultrasound-particularly, point-of-care musculoskeletal ultrasound-has emerged as a promising imaging modality for the early detection and management of hemophilic arthropathy, and for the evaluation of hemarthrosis and painful musculoskeletal episodes in patients with hemophilia. This review summarizes currently available data on the emerging role of this new imaging modality, its limitations, and gaps in knowledge. The review also raises unanswered questions, highlights the need for consolidated research efforts, and delineates future directions expected to advance this technology and optimize its use in this patient population.