Real-world long-term safety and effectiveness of turoctocog alfa in the treatment of haemophilia A in Japan: results from a multicentre, non-interventional, post-marketing study

OBJECTIVES

To assess the safety and effectiveness of turoctocog alfa in previously treated patients (PTPs) and previously untreated patients (PUPs) with haemophilia A in a real-world setting in Japan.

METHODS

This multicentre, non-interventional, post-marketing study recruited patients with haemophilia A who initiated treatment with turoctocog alfa from 18 sites (08/2014-12/2018). The primary endpoint was adverse events (AEs) during the 2-year study period.

RESULTS

The safety and effectiveness analysis set included 39 patients. In total, 13 (33.3%) patients reported ≥1 AE; incidence rate was 60.4 events/100 patient-years of exposure (PYE). Treatment was withdrawn in two cases: pruritus in a PTP and factor VIII inhibitor development in a PUP. Inhibitor development occurred in 2.6% of all patients, with an incidence rate of 3.8 events/100 PYE. The rate of inhibitor development was 0%, 25% and 20% in PTPs, PUPs and PUPs with severe type, respectively. The haemostatic success rate was 91.4% for 383 bleeding episodes and 85.7% for 14 surgeries. The negative binomial annualised bleeding rate for the prophylaxis regimen was 6.19 episodes/year (95% CI, 3.69-10.38). The mean (SD) total consumption of turoctocog alfa (n = 34; excluding FVIII inhibitors) was 5,382.6 (7,180.1) IU/kg/year/patient; consumption was 4,133.1 (1,452.4) IU/kg/year/patient for prophylaxis.

DISCUSSION

The effectiveness and safety profiles were comparable to those observed in other turoctocog alfa trials; effectiveness analysis and consumption were not affected by treatment regimens.

CONCLUSION

Long-term use of turoctocog alfa therapy in clinical practice posed no newly identified safety issues and was effective for prophylaxis and treatment of bleeds in patients with haemophilia A in Japan.

An observational study of haemophilia A patients without inhibitors using the French national claims (SNDS) database

OBJECTIVES

To describe clinical characteristics, factor consumption, and events of interest in patients with haemophilia A without inhibitors receiving prophylaxis in France, and the clinical impact of switching to Elocta® in this population.

METHODS

This retrospective, observational study using the Système National des Données de Santé database, analysed data from patients with haemophilia A without inhibitors using prophylactic factor VIII (FVIII) replacement therapy during 2016-2019. Clinical characteristics, treatment patterns and switches, factor consumption, and rate of events of interest were determined. In a sub-cohort of patients treated with Elocta®, clinical characteristics, factor consumption, and rate of events of interest before and after switching to Elocta® were compared.

RESULTS

For 545 patients, with mean age (standard deviation [SD]) 25.4 (17.8) years, Elocta® was the most used treatment. Bleeding events and articular non-bleeding events leading to hospitalization occurred in 15.4% and 13.9% of patients, respectively, and 9.9% of patients had surgeries or procedures related to haemophilic arthropathy. The mean (SD) FVIII product consumption was 344 (93) IU/kg/month for extended half-life treatment, and 331 (98) IU/kg/month for standard half-life products. For the sub-cohort of 146 patients, bleeding events (SD) decreased from 0.32 (2.2) to 0.09 (0.42) events/patient/year (p = 0.227) after switching to Elocta®. There was no statistically significant difference in rates of factor consumption or articular non-bleeding events before and after initiation of Elocta®.

CONCLUSION

This study provides real-world insights that advance the understanding of treatment patterns and events of interest in patients with haemophilia A on prophylactic regimens in France.

Single centre experience of the use of emicizumab in previously untreated and minimally treated patients under 18 months of age

Emicizumab has revolutionised haemophilia A treatment landscape and significantly reduced treatment burden, particularly in the paediatric population. We conducted a retrospective study, focused on infants aged ≤18 months with severe haemophilia A. The study included 16 patients, with a median age of 8.2 months and median treatment duration of 61.6 weeks. Before commencing emicizumab, six patients were minimally treated with ≤5 exposure days while 10 were previously untreated patients. Notably, all patients had no inhibitors at baseline, and none developed new inhibitors during the study period. Emicizumab was well tolerated, with no observed side effects or major bleeding events.

A post hoc analysis of PROTECT VIII kids assessing long-term efficacy and safety of damoctocog alfa pegol in adolescents with severe haemophilia A

INTRODUCTION

The safety and efficacy of the extended half-life factor VIII (FVIII) product damoctocog alfa pegol (BAY 94-9027, Jivi®) has been demonstrated in the PROTECT VIII Kids study (NCT01775618), where male previously-treated patients (PTPs) aged <12 years old with severe haemophilia A and ≥ 50 exposure days (EDs) were treated prophylactically. The PROTECT VIII Kids extension study assessed the long-term safety and efficacy of damoctocog alfa pegol in the same population.

AIM

To evaluate the long-term impact of damoctocog alfa pegol in a post hoc subgroup analysis of adolescent patients in the PROTECT VIII Kids study and its extension from 12th birthday onwards.

METHODS

The current analysis included PTPs aged ≥12 years old, who remained in the extension for ≥6 months following their 12th birthday. The observation period was defined as the time from 12th birthday to the end of the extension period; all data from this birthday were included whether in the main study or extension phase. The main efficacy variable was annualised bleeding rate (ABR) and the main safety variable was the frequency of inhibitor development.

RESULTS

This subgroup analysis comprised 25 patients. Median observation time after 12th birthday was 3.2 years. Median total/joint/spontaneous ABRs in the observation period were 1.7/0.7/0.3, respectively. Safety findings were consistent with those reported for the overall study population; no confirmed FVIII inhibitors or anti-drug antibodies were reported.

CONCLUSIONS

Damoctocog alfa pegol is efficacious with a favourable safety profile in adolescents with haemophilia A, supporting its long-term use in children and adolescents.

Factor VIII moiety of recombinant Factor VIII Fc fusion protein impacts Fc effector function and CD16+ NK cell activation

Recombinant Factor VIII-Fc fusion protein (rFVIIIFc) is an enhanced half-life therapeutic protein product used for the management of hemophilia A. Recent studies have demonstrated that rFVIIIFc interacts with Fc gamma receptors (FcγR) resulting in the activation or inhibition of various FcγR-expressing immune cells. We previously demonstrated that rFVIIIFc, unlike recombinant Factor IX-Fc (rFIXFc), activates natural killer (NK) cells via Fc-mediated interactions with FcγRIIIA (CD16). Additionally, we showed that rFVIIIFc activated CD16+ NK cells to lyse a FVIII-specific B cell clone. Here, we used human NK cell lines and primary NK cells enriched from peripheral blood leukocytes to study the role of the FVIII moiety in rFVIIIFc-mediated NK cell activation. Following overnight incubation of NK cells with rFVIIIFc, cellular activation was assessed by measuring secretion of the inflammatory cytokine IFNγ by ELISA or by cellular degranulation. We show that anti-FVIII, anti-Fc, and anti-CD16 all inhibited indicating that these molecules were involved in rFVIIIFc-mediated NK cell activation. To define which domains of FVIII were involved, we used antibodies that are FVIII domain-specific and demonstrated that blocking FVIII C1 or C2 domain-mediated membrane binding potently inhibited rFVIIIFc-mediated CD16+ NK cell activation, while targeting the FVIII heavy chain domains did not. We also show that rFVIIIFc binds CD16 with about five-fold higher affinity than rFIXFc. Based on our results we propose that FVIII light chain-mediated membrane binding results in tethering of the fusion protein to the cell surface, and this, together with increased binding affinity for CD16, allows for Fc-CD16 interactions to proceed, resulting in NK cellular activation. Our working model may explain our previous results where we observed that rFVIIIFc activated NK cells via CD16, whereas rFIXFc did not despite having identical IgG1 Fc domains.

FRONTIER1: a partially randomized phase 2 study assessing the safety, pharmacokinetics, and pharmacodynamics of Mim8, a factor VIIIa mimetic

BACKGROUND

Mim8 (denecimig) is a factor VIII (FVIII) mimetic bispecific antibody in development for the treatment of hemophilia. Data from the phase 1 part of FRONTIER1 (EudraCT: 2019-000465-20, NCT04204408, and NN7769-4513) suggested that Mim8 was well tolerated in healthy participants and exhibited pharmacokinetic (PK) properties consistent with dose proportionality.

OBJECTIVES

The partially randomized, phase 2, multiple ascending dose (MAD) part of FRONTIER1 aimed to evaluate the safety, PK, pharmacodynamics (PD), and exploratory efficacy of Mim8 in participants with hemophilia A with or without FVIII inhibitors.

METHODS

The MAD part of FRONTIER1 consisted of 42 participants, assigned to 5 cohorts, with participants in cohorts 3 and 4 randomized 1:1 to dosing weekly or every 4 weeks, respectively. Four of the 42 participants (9.5%) had FVIII inhibitors prior to study enrolment. The primary endpoint was treatment-emergent adverse events (TEAEs). PK and PD were evaluated by Mim8 plasma concentration and thrombin generation, respectively. Exploratory efficacy was assessed via the number of treated bleeds. Safety and PD parameters were also evaluated from an exploratory cohort treated with emicizumab.

RESULTS

Mim8 was well tolerated, with 1 serious TEAE (anxiety-related chest pain) deemed unrelated to Mim8. There was no dose dependency on the number, causality, type, or severity of TEAEs. PK/PD properties supported weekly to monthly dosing approaches, and few participants experienced treated bleeds beyond the lowest dose cohort (1 in cohorts 2 and 3, and 3 in cohort 5).

CONCLUSION

These data support the continued clinical development of Mim8, and FRONTIER1 has proceeded onto an extension phase.

A Generative and Causal Pharmacokinetic Model for Factor VIII in Hemophilia A: A Machine Learning Framework for Continuous Model Refinement

In rare diseases, such as hemophilia A, the development of accurate population pharmacokinetic (PK) models is often hindered by the limited availability of data. Most PK models are specific to a single recombinant factor VIII (rFVIII) concentrate or measurement assay, and are generally unsuited for answering counterfactual ("what-if") queries. Ideally, data from multiple hemophilia treatment centers are combined but this is generally difficult as patient data are kept private. In this work, we utilize causal inference techniques to produce a hybrid machine learning (ML) PK model that corrects for differences between rFVIII concentrates and measurement assays. Next, we augment this model with a generative model that can simulate realistic virtual patients as well as impute missing data. This model can be shared instead of actual patient data, resolving privacy issues. The hybrid ML-PK model was trained on chromogenic assay data of lonoctocog alfa and predictive performance was then evaluated on an external data set of patients who received octocog alfa with FVIII levels measured using the one-stage assay. The model presented higher accuracy compared with three previous PK models developed on data similar to the external data set (root mean squared error = 14.6 IU/dL vs. mean of 17.7 IU/dL). Finally, we show that the generative model can be used to accurately impute missing data (< 18% error). In conclusion, the proposed approach introduces interesting new possibilities for model development. In the context of rare disease, the introduction of generative models facilitates sharing of synthetic data, enabling the iterative improvement of population PK models.

Low-dose emicizumab prophylaxis in patients with severe hemophilia A: a retrospective study bringing new hope for our patients

BACKGROUND

Low-dose emicizumab can potentially offer a cost-effective treatment option in persons with hemophilia A, especially in developing countries.

OBJECTIVES

To compare the efficacy and safety of low-dose emicizumab with those on low-dose factor (F)VIII prophylaxis via chart review.

METHODS

After ethics approval, chart data of 2 groups of patients were reviewed: group 1 (low-dose emicizumab, n = 10; 3 mg/kg monthly without a loading dose) and group 2 (low-dose FVIII prophylaxis, n = 10; 10-20 IU/kg of FVIII concentrates twice a week). Outcomes were target joints, annual bleeding rate, annual joint bleeding rate, Hemophilia Joint Health Score, nonactivated thromboelastometry-rotational thromboelastometry clotting time, plasma emicizumab levels, and direct costs of treatment.

RESULTS

All outcome measures were significantly better in the low-dose emicizumab group than in the low-dose FVIII prophylaxis group. For nonactivated thromboelastometry-rotational thromboelastometry, median values after 6 months in the low-dose emicizumab group were comparable with values seen in patients with mild hemophilia, while the values in the low-dose FVIII prophylaxis group were similar to those of patients with moderate hemophilia. The direct cost of low-dose emicizumab was found to be approximately US $6000 and that for low-dose recombinant FVIII prophylaxis used in our study was US $6282 (the cost may range from US $3432 to $7920 depending on the type of factor) when compared to approximately US $15 000 for standard-dose emicizumab.

CONCLUSION

Low-dose emicizumab offers a cost-effective treatment option and can improve access in developing countries. These findings need to be confirmed in a larger and better-controlled study.

Emicizumab prophylaxis in infants: Single-centre experience

The hallmark of haemophilia A (HA) therapy is prophylaxis, aimed at spontaneous bleeding prevention. Emicizumab provides a viable alternative to intravenous factor replacement therapy. However, data on its use in infants are limited. This single-centre open arm prospective study reports on emicizumab prophylaxis in infants. We included severe HA patients under 1 year who started emicizumab prophylaxis since 2018, with longitudinal follow-up. The study collected data on demographics, clinical and laboratory variables, the occurrence of bleeding events, surgeries and treatment outcomes. Of the 27 enrolled infants, whose median age at prophylaxis initiation was 7 months, 24 primarily choose to start emicizumab therapy (3/27 switched from FVIII prophylaxis due to development of FVIII inhibitors). The median age for prophylaxis initiation decreased to 3 months in 2023. Following emicizumab initiation, the median calculated ABR decreased, and no intracranial haemorrhages were observed. Thrombin generation showed a significant improvement in peak height and endogenous thrombin potential at steady state after a loading period. Our study highlights a shift towards early prophylaxis in the era of non-replacement therapies. It underscores the need for continuous evaluation and refinement of treatment approaches, emphasizing personalized care and diligent monitoring in the evolving field of paediatric haemophilia care.

Etranacogene dezaparvovec gene therapy for haemophilia B (HOPE-B): 24-month post-hoc efficacy and safety data from a single-arm, multicentre, phase 3 trial

BACKGROUND

Etranacogene dezaparvovec, the first gene therapy approved for haemophilia B treatment, was shown to be superior to treatment with continuous prophylactic factor IX in terms of bleeding protection 18 months after gene therapy in a phase 3 trial. We report post-hoc 24-month efficacy and safety data from this trial to evaluate the longer-term effects of etranacogene dezaparvovec in individuals with haemophilia B.

METHODS

The phase 3 HOPE-B trial enrolled males aged 18 years or older with inherited haemophilia B, classified as severe (plasma factor IX activity level <1%) or moderately severe (plasma factor IX activity level ≥1% and ≤2%), with a severe bleeding phenotype and who were on stable continuous factor IX prophylaxis. Participants were treated with a single infusion of etranacogene dezaparvovec (2 × 1013 genome copies per kg of bodyweight). The primary endpoint, reported previously, was non-inferiority of the annualised bleeding rate (ABR) during the 52 weeks following stable factor IX expression (defined as months 7-18 after treatment) versus an at least 6-month lead-in period in which participants received their usual continuous factor IX prophylaxis, and is updated here up to month 24. Additional, post-hoc efficacy analyses, including adjusted ABR, factor IX activity, participants within factor IX ranges, and factor IX use, and safety analyses were performed at 24 months after gene therapy. Data were analysed in the full analysis set, which comprised the 54 patients who received at least a partial dose of gene therapy. The trial is ongoing and is registered with ClinicalTrials.gov, number NCT03569891.

FINDINGS

The study began on June 27, 2018, and participants were treated between January, 2019, and March, 2020; the date of data cutoff was April 21, 2022. 54 adult males (40 White, two Asian, one Black or African American, 11 other or missing) received a single intravenous infusion of etranacogene dezaparvovec and were followed for a median of 26·51 months (IQR 24·54-27·99), after a lead-in period of 7·13 months (6·51-7·82). In the updated analysis comparing months 7-24 after gene therapy to the lead-in period, mean adjusted ABR significantly reduced from 4·18 to 1·51 (p=0·0002) for all bleeds and from 3·65 to 0·99 (p=0·0001) for factor IX-treated bleeds. During each 6-month period after gene therapy, at least 67% of participants experienced no bleeding (36 of 54 during months 0-6 and stable thereafter), compared with 14 (26%) of 54 during the lead-in period. 24 months after gene therapy, 1 (2%) participant had one-stage factor IX activity less than 5%, whereas 18 (33%) had factor IX activity more than 40% (non-haemophilia range), with mean factor IX activity stable and sustained at 36·7% (SD 19·0%). 52 (96%) of 54 participants expressed endogenous factor IX, remaining free of factor IX prophylaxis at month 24. No new safety concerns were identified and no treatment-related serious adverse events or treatment-related deaths occurred. The most common treatment-related adverse events were an increase in alanine aminotransferase (nine [17%] of 54 patients), headache (eight [15%]), influenza-like illness (seven [13%]), and an increase in aspartate aminotransferase (five [9%]).

INTERPRETATION

By providing durable disease correction throughout the 24 months after gene therapy, etranacogene dezaparvovec provides a safe and effective therapeutic option for patients with severe or moderately severe haemophilia B.

FUNDING

uniQure and CSL Behring.

The benefits of gene therapy in people with haemophilia

Haemophilia is an inherited bleeding disorder which causes significant morbidity and mortality, especially in the severe form. Prophylaxis with factor replacement has high efficacy in reducing bleeding but is limited by the need for frequent intravenous infusion and fluctuations in haemostasis between doses. Additional prophylaxis therapies are being developed which may overcome some of the current treatment barriers. Gene therapy (GT) is being developed to provide a functional cure such that there is sustained factor expression and minimal to no need for additional haemostatic therapy. There are now two approved gene therapies for haemophilia which may be transformative for many individuals. Benefits of GT should go beyond increasing factor activity and reducing bleeding as persons with haemophilia aim to achieve a 'haemophilia-free mind' and health equity with optimal health and well-being.

The importance and evolution of bleeding disorder registries

Registries are excellent sources of data to address questions that are typically not evaluated in randomized clinical trials, including natural history, disease prevalence, treatment approaches and adverse events, and models of care. Global and regional registries can provide data to identify differences in outcomes and in haemophilia care between countries, economic settings, and regions, while facilitating research and data sharing. In this manuscript, we highlight five bleeding disorder registries: Country registries from Australia and China, Paediatric Network on Haemophilia Management (PedNet) data on children who have received emicizumab, data from the European Haemophilia Safety Surveillance (EUHASS) system, and data on women and girls with haemophilia from the World Federation of Haemophilia (WFH) registries. Data from these and other bleeding disorder registries have been and will continue to be used to advance patient care, understand treatment patterns and adverse reactions, and identify areas of increased need and focus.

The underevaluated impacts of the therapeutic revolution of hemophilia on women and girls

The advent of new treatment options over the last decades has markedly improved the lives of male persons with hemophilia (PwH). However, this therapeutic revolution has not benefited women and girls with hemophilia (WGH) and symptomatic carriers of the disease to the same extent as their male counterparts. This inequity is primarily due to the exclusion of WGH from clinical trials and a failure to fully recognize their specific treatment needs. Additionally, the indirect impact of innovative therapies, when used for male PwH, on the lives of mothers, other relatives, and partners of these individuals has been largely overlooked until now. In addition to improving access of WGH and carriers to new hemostatic treatments and comprehensive hemophilia care, it is imperative to strive for alleviating the mental burden imposed on them by this chronic disease. The recently proposed concept of a "hemophilia-free mind," primarily focused on male PwH, should therefore also be applied to WGH, symptomatic carriers, and the predominantly female support network of PwH.

Factor VIII genotype and the risk of developing highresponding or low-responding inhibitors in severe hemophilia A: data from the PedNet Hemophilia Cohort of 1,202 children

Not available.

How much prophylaxis is enough in haemophilia?

INTRODUCTION

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Hemophilia and hepatology, back to the future

Years ago, patients with hemophilia were often cared for because of liver issues. The use of hemoderivatives in the 1970s and 1980s, and the natural history of chronic hepatitis B and C, led to a surge of patients with cirrhosis and related complications after two or three decades. It was not until the approval of entecavir and tenofovir (2005-2008) against the B virus, and of direct-acting antiviral agents (2015) against the C virus, that a truly effective treatment became available for liver disease. Since then, patients with hemophilia disappeared from hepatology clinics and wards, apart from specific isolated problems.

Defining success in haemophilia care - Are we doing it right?

INTRODUCTION

Transformational advances have occurred in the management of haemophilia in the last decade leading to much better outcomes. However, a detailed and critical examination of its assessment and reporting show gaps in many aspects. These are discussed in this review.

METHODS

The relevant literature related to different aspects of management of haemophilia was reviewed to identify gaps which need to be addressed. These include detection and diagnosis of haemophilia, documentation and reporting of joint bleeding, its management and methods of reporting in clinical trials and practice, aspects of personalizing care as well as access to therapeutic products and the need for and organization of comprehensive care.

RESULTS

Current diagnostic approaches have more than doubled the identified number of persons with haemophilia (PWH) over the last 25 years but still constitute only ∼30% of the expected number. Joint bleeding is the primary indicator of disease severity and treatment efficacy, but there is lack of consistency and standardization in the way it is recorded and reported. Its continued use as an efficacy measure of modern treatments which maintain steady state factor levels or equivalence of >5% will lack sensitivity. The treatment of acute haemarthrosis has focussed on haemostasis and pain control, ignoring the role of inflammation in joint damage. Phenotypic heterogeneity of severe haemophilia has recognized clinical and laboratory variations based on haemostasis but not differences in local response to blood in the joint. At the organizational level, IU/capita provides a relevant measure of access to therapeutic products when the detection rate is ∼100% but is fallaciously low when detection rates are very low. With highly effective modern therapies for haemophilia and nearly no bleeding, the concept of comprehensive care team will need modifications.

CONCLUSION

As haemophilia care advances, a deeper dive is needed into the details of various aspects its management to ensure consistency and contemporary relevance.

Acquired bleeding disorders

Acquired bleeding disorders can develop in previously healthy people irrespective of age or gender but are particularly common in patients with certain underlying conditions. Here, we review recent advances in the management of acquired haemophilia A (AHA), acquired von Willebrand syndrome (AVWS), and patients with hemostatic abnormalities due to chronic liver disease (CLD). Patients with AHA can now benefit from prophylaxis with emicizumab, a therapeutic antibody that mimics the function of activated coagulation factor VIII. The treatment of AVWS remains challenging in many situations and requires careful consideration of the underlying condition. Haemostatic abnormalities in CLD are often compensated by proportional reduction in pro and anti-haemostatic factors resulting in sustained or even increased thrombin generation. Consequently, bleeding in CLD is rarely caused by haemostatic failure and infusion of plasma or coagulation factor concentrates may not be effective.

Rates of venous thromboembolism and use of thromboprophylaxis after major orthopedic surgery in patients with congenital hemophilia A or B: a systematic review

BACKGROUND

Venous thromboembolism (VTE) is a well-recognized complication after total joint replacement (TJR). Persons with hemophilia A or B are considered at low postoperative VTE risk due to their coagulation factor deficiencies, and administering pharmacologic thromboprophylaxis is often considered contraindicated. However, using factor replacement therapy could increase the postoperative VTE risk.

OBJECTIVES

To analyze best available evidences of VTE rates in persons with hemophilia A or B undergoing lower limb TJR and the use of postoperative pharmacologic thromboprophylaxis.

METHODS

We systematically screened 4 online biomedical databases to identify studies reporting VTE rates in patients with hemophilia after TJR. Case reports and case series with less than 10 patients were excluded.

RESULTS

Twenty-six observational studies were included in this systematic review, reporting 1181 TJRs in patients with hemophilia A or B. Eight studies had VTE rates as the primary outcome. Five studies reported screen-detected VTE, while 21 reported symptomatic VTE events. Overall, 17 VTE events were reported (1.4%; 95% CI, 0.9%-2.3%), including 10 (6.6%) after 151 surgeries with postoperative VTE screening and 7 (0.7%) after 1080 surgeries without postoperative screening. Thromboprophylaxis protocols were specified in 21 studies; postoperative thromboprophylaxis was used in 15 (1.3%) surgeries. This information was not available for 29.0% of the analyzed population.

CONCLUSION

Despite the low thromboprophylaxis use in patients with hemophilia, rates of symptomatic VTE after TJR appeared to be low. We also highlighted the need to better report the thrombotic outcome in persons with hemophilia to face the ongoing changes in the hemophilia landscape.

Successful initiation of hemodialysis for a hemophilia A patient with factor VIII inhibitor: a case report and literature review

We report the first case of hemophilia A with factor VIII (FVIII) inhibitor who received hemodialysis via an arteriovenous (AV) fistula. Hemophilia A is a congenital deficiency of blood coagulation FVIII that is characterized by prolonged bleeding. Approximately 30% of patients with hemophilia develop allogeneic antibodies of FVIII. The inhibitors decrease the hemostatic effect of replacement therapy; thus, the prophylaxis strategy should be well designed. Prophylactic treatment with invasive procedures is needed to prevent excessive bleeding in patients with hemophilia undergoing hemodialysis. On the contrary, hemodialysis requires attention to the development of intracircuit coagulation during dialysis. Peritoneal dialysis or hemodialysis with a long-term tunneled central venous catheter has mainly been selected as the dialysis modality for patients with hemophilia and end-stage renal disease requiring renal replacement therapy because hemodialysis with an arteriovenous fistula may result in bleeding from the puncture site after each hemodialysis session. In our patient, hemodialysis was safely performed without any anticoagulant agents, and replacement therapy with FVIII concentrates prevented bleeding after puncture of the AV fistula.

Haemophilia in the era of novel therapies: Where do inhibitors feature in the new landscape?

INTRODUCTION

The advent of therapeutic recombinant factor VIII (FVIII) and factor IX (FIX) protein infusions revolutionized the care of persons with haemophilia in the 1990s. It kicked off an era with the increasing use of prophylactic factor infusions for patients and transformed conversations around the ideal trough activity levels as well as the ultimate goals in tailored, individualized care. Our knowledge surrounding the immunologic basis of inhibitor development and treatment derives from a time when patients were receiving frequent factor infusions and focused on immune tolerance induction following inhibitor development.

DISCUSSION

More recently, care was revolutionized again in haemophilia A with the approval of emicizumab, a bispecific antibody mimicking activated FVIII function, to prevent bleeding. The use of emicizumab prophylaxis has resulted in a significantly slower accumulation of factor exposure days and continued effective prophylaxis in the case of inhibitor development. While emicizumab is effective at reducing the frequency of bleeding events in patients with haemophilia A, management of breakthrough bleeds, trauma, and surgeries still requires additional treatment. Ensuring that FVIII is a therapeutic option, particularly for life-threatening bleeding events and major surgeries is critical to optimizing the care of persons with haemophilia A. Other novel non-factor concentrate therapies, including rebalancing agents, will dramatically change the landscape for persons with haemophilia B with inhibitors.

CONCLUSION

This review discusses the changing landscape regarding the timing of inhibitor development and management strategies after inhibitor development, stressing the importance of education across the community to continue to vigilantly monitor for inhibitors and be prepared to treat persons with inhibitors.

Severe case of postpartum-acquired haemophilia A after laparoscopic cholecystectomy

Acquired factor VIII inhibitor, also known as acquired haemophilia A, has been associated with the postpartum state in young females. Treatment of acquired haemophilia A is focused on two goals: control of bleeding and eliminating the factor VIII inhibitor. Management requires successful intervention to accomplish both goals. Here, we describe the presentation and management of a case of acquired haemophilia A resulting in particularly severe and protracted intra-abdominal bleeding after routine laparoscopic cholecystectomy in a young and otherwise healthy female at 3 months postpartum. Due to diffuse intra-abdominal bleeding, she required return to the operating room on five occasions for intra-abdominal packing, reassessment of bleeding and ultimate fascial closure. Her abdomen was open for 5 days. She was treated with activated recombinant human factor VIIa to bypass inhibited factor VIII, and with immunosuppression using steroids, cyclophosphamide and anti-CD20 monoclonal antibody rituximab. She achieved remission after 6 weeks of treatment.

Nothing short of a revolution: Novel extended half-life factor VIII replacement products and non-replacement agents reshape the treatment landscape in hemophilia A

Hemophilia A, an X-linked genetic disorder, is characterized by a deficiency or dysfunction of clotting Factor VIII. The treatment landscape has substantially changed by introducing novel extended half-life factor VIII (EHL-FVIII) replacement therapies such as efanesoctocog Alfa and non-factor replacement therapy such as emicizumab. These agents signal a shift from treatments requiring multiple weekly infusions to advanced therapies with long half-lives, offering superior protection against bleeding and improving patient adherence and quality of life. While EHL-FVIII treatment might lead to inhibitor development in some patients, non-factor replacement therapy carries thrombotic risks. Therefore, ongoing research and the generation of robust clinical evidence remain vital to guide the selection of optimal and cost-effective first-line therapies for hemophilia A patients.

Recapitulating the immune system of hemophilia A patients with inhibitors using immunodeficient mice

BACKGROUND AND AIM

Treating hemophilia A patients who develop inhibitors remains a clinical challenge. A mouse model of hemophilia A can be used to test the efficacy of strategies for inhibitor suppression, but the differences in the immune systems of mice and humans limit its utility. To address this shortcoming, we established a humanized NOD/SCID-IL2rγnull hemophilia A (hu-NSG-HA) mouse model with a severely deficient mouse immune system presenting a patient's adapted immune cells.

METHODS AND RESULTS

Through intrasplenic injection with patient inhibitor-positive peripheral blood mononuclear cells (PBMCs), utilizing an adeno-associated viral delivery system expressing human BLyS, and regular FVIII challenge, human C19+ B cells were expanded in vivo to secrete anti-FVIII antibodies. Both the inhibitor and the human anti-FVIII IgG, including the predominant subclasses (IgG1 and IgG4) present in the majority of inhibitor patients, were detected in the mouse model. We further segregated and expanded the different clones of human anti-FVIII-secreting cells through subsequent transplantation of splenocytes derived from hu-NSG-HA mice into another NSG-HA mouse. By transplanting a patient's PBMCs into the NSG-HA mouse model, we demonstrated the success of reintroducing a strong anti-FVIII immune response for a short period in mice with the immune systems of inhibitor-positive patients.

CONCLUSION

Our results demonstrate a potential tool for directly obtaining functional human-derived antigen-specific antibodies and antibody-secreting cells, which may have therapeutic value for testing patient-specific immune responses to treatment options to assist in clinical decisions.

Clinical characteristic and management of haemophilia patients in Malaysia: A single centre experience

INTRODUCTION

Haemophilia is one of the commonest inherited bleeding disorders which may lead to long term disabilities if not treated properly. Our aim of study is to understand the clinical characteristic, treatment and complications of adult haemophilia patients in our centre.

MATERIALS AND METHODS

A retrospective cross-sectional review of all adult haemophilia A (HA) or haemophilia B (HB) patients who received treatment in Hospital Pulau Pinang from January 2021 to December 2022 was conducted. Data was retrieved from patients' medical records.

RESULTS

A total of 75 haemophilia patients (64 HA and 11 HB) were included in this study with median age of 37 years (range 19 70). 42 of them had severe haemophilia (50% of HA, 91% of HB). All HB and 93.8% of severe HA patients were on prophylaxis. Six severe and one mild HA patients developed inhibitor with four of them currently on non-factor prophylaxis. 24 patients (32%) had prior hepatitis C infection and all of them have been successfully treated. The mean annual bleeding rate for severe haemophilia patients were 1.77 (SD ±3.6). Target joints were observed in 9.3% of patients with ankle joint (71.4%) being the most affected joint. More than one quarter (26.7%) of our patients have comorbidities with majority of them having hypertension (17/20), followed by diabetes mellitus (5/20) and ischemic heart disease (5/20).

CONCLUSION

Our study showed that a significant number of adult patients with haemophilia have comorbidities. Apart from optimising factor replacement therapy, future planning should include improvement in screening, risk modification and prevention of cardiovascular disease.

Subcutaneous Marzeptacog Alfa (Activated) for On-Demand Treatment of Bleeding Events in Subjects With Hemophilia A or B With Inhibitors

Marzeptacog alfa (MarzAA) is under development for subcutaneous treatment of episodic bleeds in patients with hemophilia A/B and was studied in a phase III trial evaluating MarzAA compared with standard-of-care (SoC) for on-demand use. The work presented here aimed to evaluate MarzAA and SoC treatment of bleeding events on a standardized four-point efficacy scale (poor, fair, good, and excellent). Two continuous-time Markov modeling approaches were explored; a four-state model analyzing all four categories of bleeding improvement and a two-state model analyzing a binarized outcome (treatment failure (poor/fair), and treatment success (good/excellent)). Different covariates impacting improvement of bleeding episodes as well as a putative relationship between MarzAA exposure and improvement of bleeding episodes were evaluated. In the final four-state model, higher baseline diastolic blood pressure and higher age (> 33 years of age) were found to negatively and positively impact improvement of bleeding condition, respectively. Bleeding events occurring in knees and ankles were found to improve faster than bleeding events at other locations. The covariate effects had most impact on early treatment success (≤ 3 hours) whereas at later timepoints (> 12 hours), treatment success was similar for all patients indicating that these covariates might be clinically relevant for early treatment response. A statistically significant relationship between MarzAA zero-order absorption and improvement of bleedings (P < 0.05) were identified albeit with low precision. No statistically significant difference in treatment response between MarzAA and intravenous SoC was identified, indicating the potential of MarzAA for treatment of episodic bleeding events with a favorable subcutaneous administration route.

The current challenges faced by people with hemophilia B

Hemophilia B (HB) is a rare, hereditary disease caused by a defect in the gene encoding factor IX (FIX) and leads to varying degrees of coagulation deficiency. The prevailing treatment for people with HB (PWHB) is FIX replacement product. The advent of recombinant coagulation products ushered in a new era of safety, efficacy, and improved availability compared with plasma-derived products. For people with severe HB, lifelong prophylaxis with a FIX replacement product is standard of care. Development of extended half-life FIX replacement products has allowed for advancements in the care of these PWHB. Nonetheless, lifelong need for periodic dosing and complex surveillance protocols pose substantive challenges in terms of access, adherence, and healthcare resource utilization. Further, some PWHB on prophylactic regimens continue to experience breakthrough bleeds and joint damage, and subpopulations of PWHB, including women, those with mild-to-moderate HB, and those with inhibitors to FIX, experience additional unique difficulties. This review summarizes the current challenges faced by PWHB, including the unique subpopulations; identifying the need for improved awareness, personalized care strategies, and new therapeutic options for severe HB, which may provide future solutions for some of the remaining unmet needs of PWHB.

Intra-articular injection of tranexamic acid in patients with haemophilia arthritis: retrospective controlled study in total knee arthroplasty

PURPOSE

Total knee arthroplasty is the main method for the treatment of advanced haemophilic knee arthritis. Due to the particularity of hemophilia, the blood management plan is the focus of the perioperative period for haemophilia patients. This study aimed to investigate the clinical effect and safety of intra-articular injection of tranexamic acid in patients with haemophilia.

METHODS

This is a retrospective study. According to whether tranexamic acid is used or not, patients are divided into tranexamic acid group (n=30) and non-tranexamic acid group (n=29). Total blood loss, intraoperative blood loss, complete blood count, total amount of coagulation factor VIII (FVIII) usage, coagulation biomarkers, inflammatory biomarkers, knee range of motion, knee joint function, pain status, complication rate, and patient satisfaction were assessed and compared at a mean follow-up of 16 months.

RESULTS

Injecting tranexamic acid into the knee joint cavity can effectively reduce the hidden blood loss and total blood loss (P<0.001), and reduce the patient's early postoperative inflammation biomarkers, pain status, and limb swelling. Therefore, the patient can obtain a better range of motion following total knee arthroplasty. In the long run, in terms of joint function and surgical satisfaction, there are no statistically significant differences. In addition, there are no statistically significant differences between the two groups of patients in terms of the total amount of FVIII usage, length of stay, and hospitalization expenses.

CONCLUSION

In patients with haemophilia, intra-articular injection of tranexamic acid during total knee arthroplasty can effectively reduce postoperative blood loss, early postoperative inflammation levels, pain and limb swelling, and enable patients to receive higher-quality rehabilitation exercises to get better joint function. Previous studies on TKA in haemophilic patients have already demonstrated the efficacy of intra-articular injections of TXA in reducing postoperative blood loss. Our study confirms this efficacy.

Pharmacokinetic-Pharmacodynamic Modelling in Hemophilia A: Relating Thrombin and Plasmin Generation to Factor VIII Activity After Administration of a VWF/FVIII Concentrate

BACKGROUND

Hemophilia A patients are treated with factor (F) VIII prophylactically to prevent bleeding. In general, dosage and frequency are based on pharmacokinetic measurements. Ideally, an alternative dose adjustment can be based on the hemostatic potential, measured with a thrombin generation assay (TGA), like the Nijmegen hemostasis assay.

OBJECTIVE

The objective of this study was to investigate the predicted performance of a previously developed pharmacokinetic-pharmacodynamic model for FVIII replacement therapy, relating FVIII dose and FVIII activity levels with thrombin and plasmin generation parameters.

METHODS

Pharmacokinetic and pharmacodynamic measurements were obtained from 29 severe hemophilia A patients treated with pdVWF/FVIII concentrate (Haemate P®). The predictive performance of the previously developed pharmacokinetic-pharmacodynamic model was evaluated using nonlinear mixed-effects modeling (NONMEM). When predictions of FVIII activity or TGA parameters were inadequate [median prediction error (MPE) > 20%], a new model was developed.

RESULTS

The original pharmacokinetic model underestimated clearance and was refined based on a two-compartment model. The pharmacodynamic model displays no bias in the observed normalized thrombin peak height and normalized thrombin potential (MPE of 6.83% and 7.46%). After re-estimating pharmacodynamic parameters, EC50 and Emax values were relatively comparable between the original model and this group. Prediction of normalized plasmin peak height was inaccurate (MPE 58.9%).

CONCLUSION

Our predictive performance displayed adequate thrombin pharmacodynamic predictions of the original model, but a new pharmacokinetic model was required. The pharmacodynamic model is not factor specific and applicable to multiple factor concentrates. A prospective study is needed to validate the impact of the FVIII dosing pharmacodynamic model on bleeding reduction in patients.

Non-clotting factor therapies for preventing bleeds in people with congenital hemophilia A or B

BACKGROUND

Management of congenital hemophilia A and B is by prophylactic or on-demand replacement therapy with clotting factor concentrates. The effects of newer non-clotting factor therapies such as emicizumab, concizumab, marstacimab, and fitusiran compared with existing standards of care are yet to be systematically reviewed.

OBJECTIVES

To assess the effects (clinical, economic, patient-reported, and adverse outcomes) of non-clotting factor therapies for preventing bleeding and bleeding-related complications in people with congenital hemophilia A or B compared with prophylaxis with clotting factor therapies, bypassing agents, placebo, or no prophylaxis.

SEARCH METHODS

We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group's Coagulopathies Trials Register, electronic databases, conference proceedings, and reference lists of relevant articles and reviews. The date of the last search was 16 August 2023.

SELECTION CRITERIA

Randomized controlled trials (RCTs) evaluating people with congenital hemophilia A or B with and without inhibitors, who were treated with non-clotting factor therapies to prevent bleeds.

DATA COLLECTION AND ANALYSIS

Two review authors independently reviewed studies for eligibility, assessed risk of bias, and extracted data for the primary outcomes (bleeding rates, health-related quality of life (HRQoL), adverse events) and secondary outcomes (joint health, pain scores, and economic outcomes). We assessed the mean difference (MD), risk ratio (RR), 95% confidence interval (CI) of effect estimates, and evaluated the certainty of the evidence using GRADE.

MAIN RESULTS

Six RCTs (including 397 males aged 12 to 75 years) were eligible for inclusion. Prophylaxis versus on-demand therapy in people with inhibitors Four trials (189 participants) compared emicizumab, fitusiran, and concizumab with on-demand therapy in people with inhibitors. Prophylaxis using emicizumab likely reduced annualized bleeding rates (ABR) for all bleeds (MD -22.80, 95% CI -37.39 to -8.21), treated bleeds (MD -20.40, 95% CI -35.19 to -5.61), and annualized spontaneous bleeds (MD -15.50, 95% CI -24.06 to -6.94), but did not significantly reduce annualized joint and target joint bleeding rates (AjBR and AtjBR) (1 trial; 53 participants; moderate-certainty evidence). Fitusiran also likely reduced ABR for all bleeds (MD -28.80, 95% CI -40.07 to -17.53), treated bleeds (MD -16.80, 95% CI -25.80 to -7.80), joint bleeds (MD -12.50, 95% CI -19.91 to -5.09), and spontaneous bleeds (MD -14.80, 95% CI -24.90 to -4.71; 1 trial; 57 participants; moderate-certainty evidence). No evidence was available on the effect of bleed prophylaxis using fitusiran versus on-demand therapy on AtjBR. Concizumab may reduce ABR for all bleeds (MD -12.31, 95% CI -19.17 to -5.45), treated bleeds (MD -10.10, 95% CI -17.74 to -2.46), joint bleeds (MD -9.55, 95% CI -13.55 to -5.55), and spontaneous bleeds (MD -11.96, 95% CI -19.89 to -4.03; 2 trials; 78 participants; very low-certainty evidence), but not target joint bleeds (MD -1.00, 95% CI -3.26 to 1.26). Emicizumab prophylaxis resulted in an 11.31-fold increase, fitusiran in a 12.5-fold increase, and concizumab in a 1.59-fold increase in the proportion of participants with no bleeds. HRQoL measured using the Haemophilia Quality of Life Questionnaire for Adults (Haem-A-QoL) physical and total health scores was improved with emicizumab, fitusiran, and concizumab prophylaxis (low-certainty evidence). Non-serious adverse events were higher with non-clotting factor therapies versus on-demand therapy, with injection site reactions being the most frequently reported adverse events. Transient antidrug antibodies were reported for fitusiran and concizumab. Prophylaxis versus on-demand therapy in people without inhibitors Two trials (208 participants) compared emicizumab and fitusiran with on-demand therapy in people without inhibitors. One trial assessed two doses of emicizumab (1.5 mg/kg weekly and 3.0 mg/kg bi-weekly). Fitusiran 80 mg monthly, emicizumab 1.5 mg/kg/week, and emicizumab 3.0 mg/kg bi-weekly all likely resulted in a large reduction in ABR for all bleeds, all treated bleeds, and joint bleeds. AtjBR was not reduced with either of the emicizumab dosing regimens. The effect of fitusiran prophylaxis on target joint bleeds was not assessed. Spontaneous bleeds were likely reduced with fitusiran (MD -20.21, 95% CI -32.12 to -8.30) and emicizumab 3.0 mg/kg bi-weekly (MD -15.30, 95% CI -30.46 to -0.14), but not with emicizumab 1.5 mg/kg/week (MD -14.60, 95% CI -29.78 to 0.58). The percentage of participants with zero bleeds was higher following emicizumab 1.5 mg/kg/week (50% versus 0%), emicizumab 3.0 mg/kg bi-weekly (40% versus 0%), and fitusiran prophylaxis (40% versus 5%) compared with on-demand therapy. Emicizumab 1.5 mg/kg/week did not improve Haem-A-QoL physical and total health scores, EQ-5D-5L VAS, or utility index scores (low-certainty evidence) when compared with on-demand therapy at 25 weeks. Emicizumab 3.0 mg/kg bi-weekly may improve HRQoL measured by the Haem-A-QoL physical health score (MD -15.97, 95% CI -29.14 to -2.80) and EQ-5D-5L VAS (MD 9.15, 95% CI 2.05 to 16.25; 1 trial; 43 participants; low-certainty evidence). Fitusiran may result in improved HRQoL shown as a reduction in Haem-A-QoL total score (MD -7.06, 95% CI -11.50 to -2.62) and physical health score (MD -19.75, 95% CI -25.76 to -11.94; 1 trial; 103 participants; low-certainty evidence). The risk of serious adverse events in participants without inhibitors also likely did not differ following prophylaxis with either emicizumab or fitusiran versus on-demand therapy (moderate-certainty evidence). Transient antidrug antibodies were reported in 4% (3/80) participants to fitusiran, with no observed effect on antithrombin lowering. A comparison of the different dosing regimens of emicizumab identified no differences in bleeding, safety, or patient-reported outcomes. No case of treatment-related cancer or mortality was reported in any study group. None of the included studies assessed our secondary outcomes of joint health, clinical joint function, and economic outcomes. None of the included studies evaluated marstacimab.

AUTHORS' CONCLUSIONS

Evidence from RCTs shows that prophylaxis using non-clotting factor therapies compared with on-demand treatment may reduce bleeding events, increase the percentage of individuals with zero bleeds, increase the incidence of non-serious adverse events, and improve HRQoL. Comparative assessments with other prophylaxis regimens, assessment of long-term joint outcomes, and assessment of economic outcomes will improve evidence-based decision-making for the use of these therapies in bleed prevention.

Lipid nanoparticles and siRNA targeting plasminogen provide lasting inhibition of fibrinolysis in mouse and dog models of hemophilia A

Antifibrinolytic drugs are used extensively for on-demand treatment of severe acute bleeding. Controlling fibrinolysis may also be an effective strategy to prevent or lessen chronic recurring bleeding in bleeding disorders such as hemophilia A (HA), but current antifibrinolytics have unfavorable pharmacokinetic profiles. Here, we developed a long-lasting antifibrinolytic using small interfering RNA (siRNA) targeting plasminogen packaged in clinically used lipid nanoparticles (LNPs) and tested it to determine whether reducing plasmin activity in animal models of HA could decrease bleeding frequency and severity. Treatment with the siRNA-carrying LNPs reduced circulating plasminogen and suppressed fibrinolysis in wild-type and HA mice and dogs. In HA mice, hemostatic efficacy depended on the injury model; plasminogen knockdown improved hemostasis after a saphenous vein injury but not tail vein transection injury, suggesting that saphenous vein injury is a murine bleeding model sensitive to the contribution of fibrinolysis. In dogs with HA, LNPs carrying siRNA targeting plasminogen were as effective at stabilizing clots as tranexamic acid, a clinical antifibrinolytic, and in a pilot study of two dogs with HA, the incidence of spontaneous or excess bleeding was reduced during 4 months of prolonged knockdown. Collectively, these data demonstrate that long-acting antifibrinolytic therapy can be achieved and that it provides hemostatic benefit in animal models of HA.

Barriers to gene therapy, understanding the concerns people with haemophilia have: an exigency sub-study

BACKGROUND

Gene therapy has the potential to offer people with haemophilia (PwH) a life free from bleeding and the burden posed by current treatment regimens. To date, gene therapy has only been available in clinical trial settings, to PwH without pre-existing or historical factor inhibitors, significant concomitant liver damage or pre-existing neutralising antibodies to the adeno-associated viruses used to deliver the therapy. Thus, most PwH treated at centres not currently involved in gene therapy trials, either as a referral/follow-up centre or as a dosing centre, have been unable to access the therapy. This Exigency sub-study aims to gain a greater understanding of the opinions of PwH in the United Kingdom who have not had access to gene therapy: asking what they understand, what concerns they have, and whether they perceive any barriers preventing their access to gene therapy.

RESULTS

Twenty-three PwH were approached; 14 consented, and one withdrew prior to interview. The mean age of the participants was 35.7 years (range 25-74 years). Eleven had haemophilia A and two haemophilia B. Two were treated with standard half-life factor products, five with extended half-life products, five with a FVIII mimetic and one with a clinical trial product. One family member (a participant's partner) was also interviewed. The participants identified four barriers to gene therapy: concerns about the process of gene therapy (Expectations), uncertainty about the results (outcomes), (Access) to treatment, and a lack of understanding about gene therapy (education).

CONCLUSIONS

This Exigency study subgroup sees gene therapy as a positive treatment development that promises an improved quality of life. For this participant group, four issues impact their decision to undergo gene therapy. If the promise of gene therapy is to be realised, these barriers need to be acknowledged and addressed by healthcare professionals, patient organisations, and gene therapy providers.

[Efficacy and safety of prophylaxis with emicizumab in hemophilia A: A study of 13 patients]

INTRODUCTION

Emicizumab is the first non-replacement therapy for prophylaxis in severe hemophilia A.

AIMS

The principal aim of this study is to describe the results of our patients in prophylaxis with emicizumab, according to the usual clinical practice.

MATERIAL AND METHODS

Follow-up of 13 patients from the start of prophylaxis, recording of bleeding, surgeries, adverse reactions and the need or not for factor therapy. Plasma levels were measured at follow-up visits, the technique was coagulative in one stage, modified by 1:20 dilution.

RESULTS

Median plasma levels were 52.2mg [30.7-71.9]. Prophylaxis was safe and effective; only one spontaneous haemorrhage was recorded over time and no treatment was required. There were no thromboembolic events or serious hypersensitivity, anaphylaxis or anaphylactoid reactions. The incidence of injection site reactions was 8%. Perioperative management in minor interventions was carried out without adjuvant factorial therapy, in 2 major surgeries a dose of plasmatic FVIII concentrate was required in the patient with hemophilia A without inhibitor and FVII in the patient with inhibitor, and it was sufficient to stop the bleeding.

CONCLUSION

This study demonstrated emicizumab pharmacokinetics and its half life ensure optimal levels with prophylaxis treatment at doses established in the technical data sheet.

Emicizumab-mediated hemostatic function assessed by thrombin generation assay in an in vitro model of factor VIII-depleted thrombophilia plasma

Patients with hemophilia A (PwHA) may have concurrent deficiency of representative anticoagulant proteins, protein (P)C, PS, and antithrombin (AT), which reduces bleeding frequency. However, emicizumab-driven hemostasis in PwHA with such thrombophilic potential remains unclarified. This study investigated the influence of natural anticoagulants on emicizumab-driven coagulation in HA model plasma. Various concentrations of PS and AT were added to PS-deficient plasma and AT-deficient plasma in the presence of anti-FVIII antibody (FVIIIAb; 10BU/mL). PC-deficient plasma was mixed with normal plasma at various concentrations in the presence of FVIIIAb. Emicizumab (50 µg/mL) was added to these thrombophilic HA model plasmas, prior to tissue factor/ellagic acid-triggered thrombin generation assays. Co-presence of emicizumab increased peak thrombin values (PeakTh) dependent on PS, AT, and PC concentrations. Maximum coagulation potentials in the PS-reduced HA model plasmas remained normal in the presence of emicizumab. PeakTh were close to normal in the presence of 50%AT irrespective of emicizumab, but were higher than normal in the presence of 25%AT. Addition of recombinant FVIIa (corresponding to an administered dose of 90 μg/kg) enhanced coagulation potential to normal levels. Our findings provide novel information on hemostatic regulation in emicizumab-treated PwHA with a possible thrombophilic disposition.

Interim analyses of the multinational real-world prospective cohort HEM-POWR study evaluating the effectiveness and safety of damoctocog alfa pegol in patients with hemophilia A

OBJECTIVES

To assess effectiveness and safety of damoctocog alfa pegol in interim analyses of the ongoing real-world hemophilia A HEM-POWR study.

METHODS

HEM-POWR (NCT03932201) is a multinational Phase 4 prospective observational study. The primary objective was annualized bleeding rate (ABR) in previously treated patients (PTPs) with hemophilia A. Secondary objectives included adverse events and number of affected joints.

RESULTS

At data cut-off (August 17, 2022), the safety analysis set included 268 patients and the full analysis set (FAS) included 161 patients. The most common dosing regimen during observation period was prophylaxis (FAS = 158/161, 98.1%) every 3-4 days (twice weekly; FAS = 78/158, 49.4%) and a median (min, max) infusion dose of 37.5 (10, 72) IU/kg. PTPs receiving prophylactic damoctocog alfa pegol have fewer infusions compared with prior treatment. Median total ABR (Q1, Q3) was 0.0 (0.0, 1.8) and mean total ABR (SD) was 2.4 (8.2). The proportion of patients with no affected joints increased between initial visit and follow-up. No FVIII inhibitors, treatment-related adverse events, or deaths were reported.

CONCLUSIONS

Damoctocog alfa pegol shows effectiveness and acceptable safety, as well as consistent utilization, in real-world PTPs with hemophilia A, including in patients with non-severe hemophilia and those with a history of inhibitors. Please see video for a summary of this study.

Acute treatment of intracranial hemorrhage complicated by hemophilia a and emicizumab therapy

Among patients with hemophilia A with or without FVIII inhibitors, emicizumab prophylaxis has demonstrated significantly reduced bleeding events. However, emicizumab interferes with clotting-based assays used for monitoring FVIII activity, resulting in falsely elevated FVIII activity. This lack of accurate monitoring can complicate the dosing of intravenous therapeutic FVIII clotting factor concentrates in the treatment of critical bleeding events. This case report aims to inform providers who frequently treat hemophilia-associated hemorrhages about emicizumab's effect on clotting-based assays essential for monitoring factor replacement.

Current status of treatment and disease burden of a cohort of hemophilia B in China

Objective

Hemophilia B is a rare X-chromosome linked hereditary bleeding disorder. Patients require lifelong treatment and it is costly, but there is a lack of research in China on the treatment and burden for this group. Our aim was to review the actual treatment pattern of hemophilia B patients in China, and describe the financial burden and other disease burden from the patient's perspective.

Methods

Using data collected by the Beijing Hemophilia Home Care Center, descriptive statistics were made on the sociodemographic characteristics and treatment of patients. The annual drug costs were calculated according to the actual factor dosage and price.

Results

During the study period, 29.9% of the patients only received on-demand treatment, while the rest of the patients received varying numbers of prophylaxis treatment. The total cost of clotting factors for 341 patients in one year was 16.0 million CNY ($2.5 million), with 46990.8 CNY ($7283.7) per patient. The drug cost of prophylaxis was significantly higher than that of on-demand treatment. The amount of prothrombin complex concentrates used by patients was the largest, more than 5 times of recombinant coagulation factor IX. Based on the average annual wage and average working time of Chinese employees in 2021, the average annual wage loss of HB patients reached 31544.2 CNY ($4889.4). The results of the questionnaire showed that 77.1% and 65.3% of patients had chronic pain and acute pain of different frequencies.

Conclusion

The level of prophylaxis for Chinese patients is low; safer and more effective recombinant drugs are not widely available. Patients also face a high burden of drug costs, as well as indirect costs that cannot be underestimated. Therefore, continued efforts are needed to improve the quality of life of patients by reducing their financial burden and promote standardized treatment.

Relapse of Acquired Hemophilia A after COVID-19 Infection

Acquired hemophilia A (AHA) is a rare disease in which an autoantibody causes bleeding by interacting with and inhibiting the coagulation activity of endogenous factor VIII (FVIII). Most cases of AHA are idiopathic; known causes include autoimmune diseases, malignant tumors, pregnancy, drugs, and viral infections. An 86-year-old man was diagnosed with AHA based on the following results: an activated partial thromboplastin time (aPTT) extension of 130.7 seconds, presence of an inhibitor pattern in a mixing study, an endogenous factor VIII (FVIII) level of <1%, and an FVIII inhibitor titer of >5.1 Bethesda units (BU). The activity of von Willebrand factor (vWF) was diminished (<10%), which was considered a complication of acquired von Willebrand syndrome (AVWS). The patient was started on prednisolone, and the inhibitor level eventually became negative. vWF values also became normal. However, 1 year later, he was hospitalized for treatment of coronavirus disease 2019 (COVID-19). Blood testing showed an aPTT extension of 110.5 seconds, FVIII level of 4%, and FVIII inhibitor titer of 0.8 BU; thus, a relapse of AHA was diagnosed. After administration of corticosteroid and remdesivir, he recovered from COVID-19 and AHA. The inhibitor level became negative on the 9th day of admission. Several studies have implicated COVID-19 infection and vaccination in AHA. We recommend that aPTT be measured when patients with AHA are infected with SARS-CoV2, to confirm AHA relapse.

Balancing anticoagulation and hemostasis in an infant with severe hemophilia A during cardiac transplantation: Review of the literature and development of a surgical protocol

Hemophilia A is a disorder resulting in a deficiency of clotting factor VIII that can lead to life-threatening bleeding. Evidence-based guidelines for surgical interventions like cardiac surgery are limited. Anticoagulation is necessary for cardiac bypass, thus risk of bleeding in a patient with hemophilia is increased and requires careful attention to maintain hemostasis. We report the first infant with severe hemophilia A and dilated cardiomyopathy who underwent successful cardiac transplantation, and review the literature on previous cardiac transplant cases in congenital hemophilia. To ensure safe and effective management, a multidisciplinary approach was used to develop the surgical protocol for transplant.

Occupational therapy in the management of haemophilia patients: A scoping review

BACKGROUND

Haemophilia is a haematological disease, although most haemorrhages occur in the locomotor system. Patients are physically disabled from an early age and have a poorer perception of quality of life. In the day-to-day lives of patients and their families, psychosocial well-being, the disease's physical, personal, and social impact, as well as work-related problems are the most complicated aspects of the disease that need to be addressed.

OBJECTIVE

To identify the role of occupational therapy in managing patients with haemophilia and to analyse the therapeutic potential of occupational therapy in treating these patients.

METHODS

A scoping review was conducted to identify the role of occupational therapy in managing patients with haemophilia and to analyse the therapeutic potential of occupational therapy in treating these patients. The review was registered in the international registry PROSPERO (Id: CRD42022319637). The databases consulted were SCOPUS, PubMed, PsycINFO, Web of Science and Science Direct, including all studies published until 14 August 2023.

RESULTS

No single study was found that specifically developed an occupational therapy intervention for patients with haemophilia. Measurement instruments have been identified, specific for patients with haemophilia and generic, that can be useful for the functional evaluation of these patients in the occupational therapy approach. Different studies showed the importance of multidisciplinary treatment, including occupational therapy.

CONCLUSIONS

The use of occupational therapy could be effective in improving autonomy and quality of life in haemophilia patients. Therefore, it is of paramount importance to conduct research studies within the field of occupational therapy.

[Successful immunosuppressive therapy in female hemophilia A developing inhibitor after perioperative administration of factor VIII products]

A 62-year-old woman was diagnosed as a hemophilia A carrier (factor VIII activity 35%) on preoperative examination of an ovarian tumor. A total of 35,600 units of recombinant factor VIII products was administered perioperatively. On postoperative day 95, a subcutaneous hematoma formed and immunosuppressive therapy with prednisolone was started based on an APTT of 66 seconds, factor VIII (FVIII) activity of 3%, and FVIII inhibitor of 1 BU/ml. During this treatment, the patient was hospitalized due to ankle joint bleeds and required hemostatic treatment, but the inhibitor disappeared and FVIII activity recovered to 30% after postoperative day 438 with cyclophosphamide. F8 analysis revealed the patient carried a heterozygosity of p.Arg391Cys, which has previously been categorized as cross-reacting material (CRM)-positive severe hemophilia A. No high-risk mutations for inhibitor development were found. We also report the results of a desmopressin acetate hydrate test administered to the patient to prepare for future treatment in case of hemorrhage, since high-dose FVIII administration may have been a factor in inhibitor development.

[Methodological recommendations for surgical care in patients with hemophilia A receiving prophylactic therapy with emicizumab]

Methodological recommendations for surgical care in patients with hemophilia A receiving prophylactic therapy with emicizumab. Recommendations of the expert group. Moscow, 2024.

Association of patient, treatment and disease characteristics with patient-reported outcomes: Results of the ECHO Registry

INTRODUCTION

Patient-reported outcomes (PROs) in people living with haemophilia A (PLWHA) are often under-reported. Investigating PROs from a single study with a diverse population of PLWHA is valuable, irrespective of FVIII product or regimen.

AIM

To report available data from the Expanding Communications on Haemophilia A Outcomes (ECHO) registry investigating the associations of patient, treatment and disease characteristics with PROs and clinical outcomes in PLWHA.

METHODS

ECHO (NCT02396862), a prospective, multinational, observational registry, enrolled participants aged ≥16 years with moderate or severe haemophilia A using any product or treatment regimen. Data collection, including a variety of PRO questionnaires, was planned at baseline and annually for ≥2 years. Associations between PRO scores and patient, treatment and disease characteristics were determined by statistical analyses.

RESULTS

ECHO was terminated early owing to logistical constraints. Baseline data were available from 269 PLWHA from Europe, the United States and Japan. Most participants received prophylactic treatment (76.2%), with those using extended-half-life products (10.0%) reporting higher treatment satisfaction. Older age and body weight >30 kg/m2 (>BMI) were associated with poorer joint health. Older age was associated with poorer physical functioning and work productivity. Health-related quality of life and pain interference also deteriorated with age and >BMI; >BMI also increased pain severity scores.

CONCLUSION

ECHO captured a variety of disease characteristics, treatment patterns, PROs and clinical outcomes obtained in real-world practice with ≤1 year's follow-up. Older age, poorer joint health and >BMI adversely affected multiple aspects of participant well-being.