Effects of coagulation factors on bone cells and consequences of their absence in haemophilia a patients.

Haemophilia is associated with reduced bone mass and mineral density. Due to the rarity of the disease and the heterogeneity among the studies, the pathogenesis of bone loss is still under investigation. We studied the effects of coagulation factors on bone cells and characterized in a pilot study the osteoclastogenic potential of patients' osteoclast precursors. To evaluate the effect of coagulation factors on osteoclasts, we treated Healthy Donor-Peripheral Blood Mononuclear Cells (HD-PBMC) with Factor VIII (FVIII), von Willebrand Factor (VWF), FVIII/VWF complex, activated Factor IX (FIXa), activated Factor X (FXa) and Thrombin (THB). FVIII, VWF, FVIII/VWF, FXa and THB treatments reduced osteoclast differentiation of HD-PBMC and VWF affected also bone resorption. Interestingly, PBMC isolated from patients with moderate/severe haemophilia showed an increased osteoclastogenic potential due to the alteration of osteoclast precursors. Moreover, increased expression of genes involved in osteoclast differentiation/activity was revealed in osteoclasts of an adult patient with moderate haemophilia. Control osteoblasts treated with the coagulation factors showed that FVIII and VWF reduced ALP positivity; the opposite effect was observed following THB treatment. Moreover, FVIII, VWF and FVIII/VWF reduced mineralization ability. These results could be important to understand how coagulation factors deficiency influences bone remodeling activity in haemophilia.

Moderate haemophilia A: Recommendations from a Spanish panel of experts.

INTRODUCTION: Diagnosing moderate haemophilia A (MHA) solely based on deficient FVIII protein levels limits its optimal management and delays the initiation of prophylaxis. Updating protocols and incorporating new variables into its diagnosis could prevent underestimating disease severity, avoiding early arthropathies and impairing patients' quality of life. AIM: To propose recommendations to improve the comprehensive management of people with MHA. METHODS: Recommendations from a Spanish panel of eight experts from public comprehensive care centres (CCCs) for people with haemophilia and over 140 people with MHA in follow-up. In a previous analysis, the panel identified the unmet needs of people with MHA and the necessity to develop new specific recommendations for their management. RESULTS: The panel proposed recommendations in four areas: diagnosis, treatment, follow-up and referrals. They detailed the necessary steps and procedures for the diagnosis, adding other variables to the FVIII levels like bleeding phenotype, genetic profile and joint status to specify the severity and risk classification of people with MHA. Experts proposed an algorithm with unique independent criteria to facilitate the decision to initiate prophylaxis, where the recommended FVIII levels and variables coexist for treatment decision-making. Follow-up proposals addressed periodicity, recommended tests and required visits to CCCs. For referrals, experts proposed criteria and situations considered urgent for a transfer to a CCC for haemophilia patients. CONCLUSION: The proposals agreed upon by this expert panel can contribute to update and optimize the management of people with MHA, delaying joint deterioration, pain and disabilities, and improving their quality of life.

Haemophilia care in Iraq; a multi-centre study.

OBJECTIVE: To evaluate the level of care available for haemophilia patients. METHODS: The descriptive, retrospective analytical study was conducted from December 15, 2020, to March 1, 2021, after approval from the Mustansiriyah University, Baghdad, Iraq, and comprised data from 3 haemophilia treating centres in Iraq participating in the World Bleeding Disorders Registry. The data collected related to patients with haemophilia A and B enrolled in the registry since March 2018, and included age at diagnosis, type of haemophilia, disease severity, age at first bleed and at first joint bleed, type of replacement therapy and outcome. Data was analysed using statistical package of social sciences (SPSS) version 20. RESULTS: Of the 638 patients with mean age 16.2±4.3 (range: 9-29 years), 581(91%) had haemophilia A, 57(8.9%) had haemophilia B, 385(60.5%) had severe haemophilia, 126(19.8%) moderate and 125(19.7%) mild. Further, 259(41%) patients had been diagnosed for <1 year. There were 1354 bleeding events, and haemarthrosis accounted for 959(70.8%) of them. The mean annualised bleeding rate for severe patients was 2 ± 0.6(range 0-4), while the mean annualised joint bleeding rate was 4 ± 1.3(range :2-8). There were 256(32.3%) patients who were tested for inhibitors, and 62(24.3%) were positive. Among 426(73.3%) haemophilia A patients with a treatment history, 248(58%) were on prophylactic therapy, and the corresponding value among 37(65%) haemophilia B patients was 17(46%). CONCLUSIONS: Access to treatment was found to be limited, and patients were found to be suffering from high bleeding rates and joint damage.

Adherence and Quality of Life in Adult Patients With Haemophilia A, Haemophilia B and Von Willebrand Disease: A National Cross-Sectional Survey.

BACKGROUND: New treatments for patients with bleeding disorders (PWB) have emerged, including products with extended half-life and subcutaneous administration. These less frequent treatments can potentially enhance quality of life (QoL), but adherence becomes critically important. AIM: To investigate adherence and QoL among PWB and explore the correlation between treatment adherence and QoL in adult patients with haemophilia A (HA), haemophilia B (HB) and Von Willebrand disease (vWD) in Denmark. METHOD: This survey used disease-specific patient-reported questionnaires: Veritas-PRO and Veritas-PRN to measure adherence, and Haemo-A-QoL and VWD-QoL to assess QoL. RESULTS: Responses were obtained from 149 patients with HA, 32 with HB and 118 with vWD. Adherence was reported by 87.1% of patients on prophylaxis and 71.2% of patients treated on demand, according to Veritas-PRO and Veritas-PRN cut-off scores. High QoL was generally reported, decreasing with age in HA and HB, but not in vWD. CONCLUSION: Danish patients with HA, HB and vWD reported high QoL and high adherence to prescribed treatments. There was no correlation between treatment adherence and QoL among the different patient groups. These findings highlight the need for further research to better understand adherence behaviours and identify opportunities to further improve QoL in PWB.

The Role of the Hemostasis and Thrombosis Unit in the Management of the Patients with Acquired Hemophilia.

Objective: Acquired hemophilia A (AHA) is a rare autoimmune disease characterised by the presence of autoantibodies against coagulation factor VIII (FVIII), leading to spontaneous haemorrhage in patients without a prior family or personal history of bleeding. This study describes the demographics, diagnosis, underlying disorders, bleeding characteristics, treatment, and outcomes of 41 AHA patients, along with specific case reports. Materials and Methods: Diagnosis and treatment occurred between 2005 and 2023. The median age at diagnosis was 67.8 years (range 15-93). Among the 41 patients, 10 (24%) were idiopathic, 4 (10%) were postpartum, 18 (44%) had autoimmune diseases, and 9 were diagnosed with cancer. Results: Diagnostic delay exceeded 30 days in 15 out of the 41 cases (36.5%). A total of 38 out of the 41 (93%) patients presented with spontaneous bleeding, with mucocutaneous bleeding being the most common presentation (23/41, 56%). Four patients experienced postpartum bleeding. Clinical remission was achieved in 100% of patients, and no patient died. Conclusion: Haemostatic and Immunosuppressive therapy is essential in AHA, and it should be started as soon as possible in patients with bleeding. However, a significant delay in diagnosis was observed. The absence of mortality is likely attributable to the management of the disease within a specialised Haemostasis and Thrombosis Unit, which offers a clinical ward, a specialised laboratory, and a dedicated ambulatory service. The Italian Society for the Study of Haemostasis and Thrombosis (SISET) is working to secure recognition for this essential role in every hospital.

Evaluating the benefits of emicizumab prophylaxis for haemophilia A with inhibitors: A cost-effectiveness and budget impact analysis in Thailand's upper-middle income setting.

BACKGROUND: In Thailand, an upper-middle-income country, managing haemophilia A (HA) with inhibitors poses significant challenges, often necessitating bypassing agents (BPAs) for bleeding control. This study evaluates the cost-effectiveness and budget impact of emicizumab, a novel prophylactic agent, as an alternative to both episodic and prophylactic BPA treatments from a societal perspective. METHODS: A Markov model was employed to estimate the lifetime societal costs and outcomes of emicizumab prophylaxis for HA patients with inhibitors. Treatment efficacy, cost, and epidemiological data were obtained through a comprehensive literature review and incorporated into the model. A 5-year budget impact analysis complemented the cost-utility analysis, with a 3% annual discount rate applied to future costs and outcomes. RESULTS: In the base-case scenario, emicizumab prophylaxis in HA patients aged 2 years and above demonstrated superior cost-effectiveness, yielding 18.1 quality-adjusted life years (QALYs) per patient over a lifetime and resulting in cost savings of 138 million Thai Baht (THB) compared to BPA prophylaxis. Compared to episodic BPA treatment, emicizumab yielded 30.5 QALYs and saved 25 million THB per patient. The 5-year budget impact was projected at 1775 million THB. CONCLUSIONS: Emicizumab offers a cost-saving approach for HA treatment with inhibitors in Thailand, promising significant health benefits and budgetary savings. This supports its potential inclusion in Thailand's National List of Essential Medicines to enhance haemophilia care access. HIGHLIGHTS: Managing haemophilia A (HA) with inhibitors in Thailand, an upper-middle-income country, faces challenges due to limited access to effective treatments or newer drugs for bleeding management. Emicizumab prophylaxis found to as a cost-effective and viable alternative to traditional treatments, effectively preventing bleeding in Thai HA patients over 2 years old with inhibitors. Demonstrating improved clinical outcomes and reduced costs, emicizumab prophylaxis outperforms episodic BPA treatments, positioning it as a superior treatment option for HA patients with inhibitors in Thailand.

Real-world effectiveness of eptacog beta in patients with haemophilia and inhibitors: A multi-institutional case series.

INTRODUCTION: The management of bleeding events (BEs) in haemophilia A (HA) and B (HB) patients with inhibitors necessitates the use of bypassing agents. The recombinant factor VIIa bypassing agent eptacog beta has demonstrated efficacy at treating BEs and managing perioperative bleeding in adults in phase three clinical studies. AIM: To provide real-world descriptions of eptacog beta use for BE treatment in patients on emicizumab or eptacog beta prophylaxis. METHODS: This is a retrospective case series of 14 patients who received eptacog beta at seven haemophilia treatment centres, with HA (n = 11) or HB (n = 3) and inhibitors or anaphylaxis to factor replacement. RESULTS: Twenty-four spontaneous and traumatic BEs are described (muscle hematomas, joint hemarthroses, port site, and epistaxis) involving 11 subjects. Eptacog beta was effective for acute bleed treatment as both first-line therapy and for treatment of BEs refractory to eptacog alfa in 23/24 events. When eptacog beta was used for prophylaxis, 2/3 patients reported a decreased frequency of breakthrough BEs compared with prophylactic eptacog alfa and one patient experienced a similar frequency of breakthrough BEs compared with prophylactic activated prothrombin complex concentrate. Eptacog beta provided effective bleed control for three subjects who underwent minor surgical procedures. Treatment with eptacog beta was estimated to be 46%-72% more cost-effective than eptacog alfa. No safety concerns or adverse events were reported. CONCLUSIONS: In this case series, eptacog beta was safe, effective, and economical as first-line therapy, treatment of refractory BEs, management of perioperative bleeding, or prophylaxis in haemophilia patients with inhibitors.

Clinical and Humanistic Burden of Non-inhibitor Haemophilia A in Five European Countries: Insights from the CHESS II Study.

INTRODUCTION: Haemophilia A (HA) is a congenital bleeding disorder caused by a deficiency/absence of factor VIII (FVIII) and characterised by frequent, acute and prolonged spontaneous or traumatic bleeding events, often leading to haemophilic arthropathy and progressive joint deterioration. HA severity is characterized by endogenous FVIII activity: mild (> 5-40%), moderate (1-5%), or severe (< 1%). HA poses a substantial clinical and socioeconomic burden on people with HA (PWHA), their caregivers, and society. This analysis evaluates clinical and patient-centric outcomes of a cohort of individuals with non-inhibitor HA sampled from France, Germany, Italy, Spain, and the UK in the 'Cost of Haemophilia in Europe: A Socioeconomic Survey II' (CHESS II) study. METHODS: CHESS II was a cross-sectional burden-of-illness study collecting clinical and socioeconomic data on adult (≥ 18 years) individuals with haemophilia A or B of any severity with or without inhibitors from eight European countries. Descriptive analyses were conducted examining physician-reported demographics, clinical and health resource utilisation information. PWHA-reported health-related quality of life (HRQoL) using the EQ-5D-5L and Work Productivity and Activity Impairment (WPAI) were also examined. Outcomes were stratified by HA severity and reported at country level. RESULTS: Demographics and clinical characteristics of the cohort (N = 880) were generally consistent across countries. Individuals with severe HA experienced more frequent bleeding events and joint disease despite broad use of factor replacement therapy long-term prophylaxis. A minority of those with mild or moderate HA also experienced such challenges. HRQoL and workforce participation diminished, and chronic pain increased, with increasing HA severity. CONCLUSION: This analysis provides up-to-date insights on the impact of HA across five European countries. Increasing HA severity was generally associated with worse clinical outcomes, HRQoL and workforce participation. These findings suggest a place for continued evidence-based tailored treatment and clinical management approaches in addressing the residual burden of HA.

A long term outcomes analysis of severe haemophilia A boys receiving 4 years prophylaxis on the Chinese Haemophilia Individualized escalating low dose Prophylaxis (CHIPS).

BACKGROUND: The Chinese Haemophilia Individualized Prophylaxis Study (CHIPS), which was launched in 2016, reported a significant reduction in haemarthrosis over a one-year study. However, its long-term efficacy requires verification. This paper summarizes the clinical outcomes of 18 severe haemophilia A (SHA) patients who completed one year on the CHIPS and 3 more years of follow-up. METHODS: Clinical follow-up was based on the CHIPS protocol (from July 2018 to July 2021). Escalation was based on index joint bleeding, and serial ultrasound (greyscale and colour Doppler) examinations of the index joints (both sides of the ankles, knees and elbows) were conducted every 6 months via a scoring system. RESULTS: A total of 18 SHA patients completed the 3-year study. Fifteen patients dropped out due to the financial crisis during the COVID-19 pandemic in China. The median age was 5.4 (range 4.3-6.9) years. A significant reduction in haemarthrosis was achieved, with mean annual bleeding rates reduced from 18.9 ± 2.8 to 1.7 ± 0.4 (p < 0.001), annual joint bleeding rates from 3.1 ± 0.7 to1.2 ± 0.3 (p < 0.028). 5 out of 8 target joint resolved. Sixteen doses were escalated. At study exit, the heterogeneous treatment outcomes of the SHA boys were 5 at step 4 (20-25 lU/kg, every other day), 10 at step 3 (15-20 IU/kg, 3×/week), 2 at step 2 (10-15 lU/kg, 3×/week) and 1 at step 1 (10-15 lU/kg, 2×/week). The mean FVIII consumption was 2964 IU/kg/year, with savings. The quality of life improved, with Canadian Haemophilia Outcomes-Kids Life Assessment Tool (CHO-KLAT, Chinese Version 2.0) scores ranging from 68.8 to 78.8. There was no change in the ultrasound score. CONCLUSION: Our follow-up data on the 18 SHA boys after completing one year on the CHIPS verify the long-term efficacy of the CHIPS for haemarthrosis reduction, joint health preservation, improvement in the quality of life of the boys and cost savings.

Exploring the relationship between condition severity and health-related quality of life in people with haemophilia A across Europe: a multivariable analysis of data from the CHESS II study.

BACKGROUND: Haemophilia A (HA; Factor VIII deficiency) is a congenital X-linked bleeding disorder characterized by trauma-related or spontaneous bleeding events, most notably arising within the intraarticular space and resulting in chronic inflammation and degeneration of affected joints. Endogenous clotting factor activity relative to normal levels determines the severity of HA symptoms, as mild (> 5-40%), moderate (1-5%), or severe (< 1%). Within the current environment of rapid evolution in HA management, we seek to understand the interplay of condition severity and health-related quality of life (HRQoL) to characterise and differentiate unmet needs among people with HA (PwHA). METHODS: A generalised linear regression model (GLM) was developed to explore the relationship between HA severity and EQ-5D-5 L index score from adult HA patients sampled in the "Cost of Haemophilia across Europe - a Socioeconomic Survey II" (CHESS II) cross-sectional, retrospective burden of illness study among adults with hereditary haemophilia A or B from eight European countries. HA patients of any severity with no active inhibitors during the 12 months prior to data capture and a completeEQ-5D-5 L response were included. A base GLM model was specified with covariates for demographic and clinical characteristics (age, body mass index, country, employment, HA severity, annual bleeding rate, problem joints, and chronic pain). RESULTS: Of 381 evaluable patients, 221 (58.0%) had severe HA, 96 (25.2%) had moderate HA, and 64 (16.8%) had mild HA. Among the covariates included in the GLM model and after controlling for haemophilia-related outcomes, a significant association was observed between mild HA and higher EQ-5D-5 L index score (average marginal effects, 0.084; p = 0.016) relative to severe HA. Patient country of residence and magnitude of HA-related chronic pain were also associated with significant differences in index scores, with the latter showing a negative relationship with HRQoL outcomes. CONCLUSIONS: Condition severity and chronic pain are significant predictors of HRQoL in PwHA. Durable bleeding protection and effective management of chronic pain have the potential to address unmet treatment needs in this population.

Disease and treatment burden of patients with haemophilia entering the explorer6 non-interventional study.

OBJECTIVES: We aimed to characterise baseline disease and treatment burden in a large population with haemophilia A/B, both with (HAwI/HBwI) and without (HA/HB) inhibitors. METHODS: The prospective, non-interventional explorer6 study included patients ≥12 years old with severe HA, severe/moderate HB or HAwI/HBwI of any severity, treated according to local standard of care (excluding previous/current exposure to concizumab or emicizumab). Baseline characteristics and historical clinical data were collected and patient-reported outcomes, including treatment burden, were assessed. RESULTS: The explorer6 study enrolled 231 patients with haemophilia (84 HAwI/HBwI) from 33 countries. At baseline, patients with HA/HB treated with prophylaxis had the lowest median annualised bleeding rates (ABRs; 2.0), irrespective of haemophilia type; of these patients, 27.5% (HA) and 31.4% (HB) had target joints. Patients with HAwI/HBwI treated episodically reported the highest treatment burden. Of these patients, 28.5% (HAwI) and 25.1% (HBwI) performed sports activities in the month before screening. CONCLUSION: Despite receiving routine clinical care, historical and baseline information from patients enrolled in explorer6 showed that patients with HA/HB treated episodically and patients with HAwI/HBwI had higher ABRs, higher treatment burden and participated in sports less than those with HA/HB treated with prophylaxis. Emerging treatments could be beneficial in addressing these unmet medical needs.

Moving towards Normalization of haemostasis and health equity: Evolving treatment goals for haemophilia A.

BACKGROUND: Treatment options for people with haemophilia are evolving at a rapid pace and a range of prophylactic treatment options using various technologies are currently available, each with their own distinct safety and efficacy profile. TREATMENT GOALS: The access to replacement therapy and prophylaxis has driven a dramatic reduction in mortality and resultant increase in life expectancy. Beyond this, the abolition of bleeds and preservation of joint health represent the expected, but rarely attained, goals of haemophilia treatment and care. These outcomes also do not address the complexity of health-related quality of life impacted by haemophilia and its treatment. CONCLUSION: Capitalizing on the major potential of therapeutic innovations, 'Normalization' of haemostasis, as a concept, should include the aspiration of enabling individuals to live as normal a life as possible, free from haemophilia-imposed limitations. To achieve this-being supported by the data reviewed in this manuscript-the concept of haemostatic and life Normalization needs to be explored and debated within the wider multidisciplinary teams and haemophilia community.

Incidence and treatment-related risk factors of inhibitor development after intensive FVIII replacement for major orthopaedic surgery in previous treated haemophilia A.

INTRODUCTION: Haemophilia A (HA) is an X-linked recessive bleeding disorder caused by lack or deficiency of coagulation factor VIII. AIM: The aim of this study is to determine the incidence and treatment-related risk factors of inhibitor development after intensive FVIII replacement for major orthopaedic surgery in previous treated persons with HA. METHODS: A total of 151 HA who underwent 221 major orthopaedic surgical procedures after intensive FVIII treatment were reviewed. The results of inhibitor tests were collected. Potential clinical risk factors for inhibitor development were analyzed. RESULTS: 111 people were diagnosed with severe HA. Thirty-seven persons (24.5%) had history of previous intensive FVIII treatment for surgical procedure. They received a mean perioperative cumulative FVIII of 498 iu/kg within first week after surgery. Seven cases (4.6%) developed an inhibitor post-operatively in our study. Surgical procedure for pseudotumor and the group of persons who experienced postoperative complications had the higher incidence of inhibitor development (9.5%, 13.3% respectively). Only previous history for intensive FVIII exposure was considered as a significant predictor for postoperative inhibitor development after multivariate logistic regression analysis (OR: 29.5, P = 0.002). CONCLUSION: The incidence of inhibitor development in previously treated persons with HA undergoing major orthopaedic surgery was 4.6% and the history of previous intensive FVIII treatment for surgery was associated with higher risk of inhibitor development.

Acquired haemophilia A in Finland: A nationwide study of incidence, treatment and outcomes.

INTRODUCTION: Acquired haemophilia A (AHA) is a bleeding disorder caused by autoantibody development against factor VIII (FVIII). Studies on AHA have mainly focused on patients treated at specialist centres. AIM: To determine the incidence, clinical characteristics and outcomes of AHA in an unselected population-based patient cohort from Finland. METHODS: This retrospective observational cohort comprised all cases diagnosed with AHA in Finland between 2006 and 2019. Patients were identified by the two central laboratories performing FVIII antibody testing in Finland, the Finnish Red Cross Blood Service and HUSLAB. Clinical details were collected from all hospitals and healthcare units where patients were treated. This study was performed in conjunction with the AHA in the Nordics study. RESULTS: The median incidence of AHA was 0.65 per million per year (range 0.19-1.27). Fifty-five patients were identified, with a median age of 76 years and an even sex ratio (51% women). When diagnosed, all had bleeding symptoms with severe bleeds in 92%. First-line immunosuppressive treatment regimens included steroid monotherapy in 31% of cases, steroids and a cytotoxic agent in 51% and a rituximab-based regimen in 16%. Clinical remission was achieved in 71% of cases, and 15% had relapses. Mortality was 13% for bleeds and 9% for treatment-related infections. Overall survival was 64% for 1 year and 56% for 2 years after diagnosis. CONCLUSIONS: In a nationwide population-based cohort study, we discovered a lower incidence of AHA than previously reported. Mortality among patients with AHA was high, calling for the consideration of updated treatment strategies.

Humanistic burden of haemophilia A without inhibitors: A cross-sectional analysis of the HemoLIFE study.

AIM: To evaluate the impact of haemophilia A without inhibitors on humanistic outcomes in patients and caregivers. Herein, we report a cross-sectional analysis of the baseline data of persons with haemophilia (PWH) participating in the prospective study HEMOLIFE. METHODS: These data are part of a prospective, observational, and multicentre study currently being conducted in 20 hospitals in Spain by haematologists. We included subjects 12 years or older diagnosed with haemophilia. The evaluations included the Maladjustment Scale, Haemophilia-Specific Quality of Life Questionnaire for Adults (HaemoQol)/HaemoQol Short Form (Children), haemophilia-specific version of the Work Productivity and Impairment Questionnaire plus the Classroom Impairment Questionnaire (WPAI+CIQ:HS), Haemophilia Activity List (HAL)/Paediatric Haemophilia Activities List (pedHAL), visual analogue scale (VAS) for evaluating pain, Coping Pain Questionnaire-Reduced (CAD-R), and Hospital Anxiety and Depression Scale (HADS). RESULTS: A total of 81 PWH were recruited at 18 centres; 66 PWH were ≥18 years (i.e., adults), and PWH 15 were <18 years (i.e., paediatric patients). Out of the 79 evaluable subjects, 16 (20%) showed an impact of haemophilia on daily life, and the areas most affected were "leisure time" (58% showed maladjustment) and "work/studies" (47% showed maladjustment). Patients reported a higher impact of haemophilia on quality of life (mean [SD] of the transformed score) in the dimensions of "sport" (49.4 [28.6]), "physical health" (40.5 [25.8]) and "future" (37.7 [28.9]). In adults, according to HAL scores, greater impairment of function was observed in "lying/sitting/kneeling/standing," "function of legs" and "leisure activities and sports," with mean normalized scores of 64.7, 65.1 and 69.0, respectively. Productivity was mostly impacted by presenteeism. The pain was infrequent and moderate. According to the HADS scores, nine (11.5%) patients had clinical anxiety and depression. CONCLUSION: PWH without inhibitors exhibited impairments in adjustment, quality of life and functionality, especially related to leisure and sports activities, and exhibit relevant levels of anxiety and depression.

Reduced doses of emicizumab achieve good efficacy: Results from a national-wide multicentre real-world study in China.

INTRODUCTION: Reduced doses of emicizumab improve the affordability among patients in developing countries. However, the relationship between variant dose selection and efficacy in the real world of China is still unclear. AIM: This study aimed to investigate the efficacy and safety of emicizumab especially in those on reduced dose regimens in a real-world setting. METHODS: We carried out a multicentre study from 28 hospitals between June 2019 and June 2023 in China and retrospectively analysed the characteristics including demographics, diagnosis, treatment, bleeding episodes, and surgical procedures. RESULTS: In total, 127 patients with haemophilia A, including 42 with inhibitors, were followed for a median duration of 16.0 (IQR: 9.0-30.0) months. Median age at emicizumab initiation was 2.0 (IQR: 1.0-4.0) years. Median (IQR) consumption for loading and maintenance was 12.0 (8.0-12.0) and 4.2 (3.0-6.0) mg/kg/4 weeks, respectively. While on emicizumab, 67 (52.8%) patients had no bleeds, whereas 60 (47.2%) patients had any bleeds, including 26 with treated bleeds. Compared to previous treatments, patients on emicizumab had significantly decreased annualized bleeding rate, annualized joint bleeding rate, target joints and intracerebral haemorrhage. Different dosages had similar efficacy except the proportion of patients with treated spontaneous bleeds and target joints. Adverse events were reported in 12 (9.4%) patients. Postoperative excessive bleeding occurred following two of nine procedures. CONCLUSION: This is the largest study describing patients with HA receiving emicizumab prophylaxis on variant dose regimens in China. We confirmed that nonstandard dose is efficacious and can be considered where full-dose emicizumab is ill affordable.

The use of Bacillus subtilis as a cost-effective expression system for production of Cholera Toxin B fused factor VIII epitope regions applicable for inducing oral immune tolerance.

Coagulation factor replacement therapy for the X-linked bleeding disorder Haemophilia, characterized by a deficiency of coagulation protein factor VIII (FVIII), is severely complicated by antibody (inhibitors) formation. The development of FVIII inhibitors drastically alters the quality of life of the patients and is associated with a tremendous increase in morbidity as well as treatment costs. The ultimate goal of inhibitor control is antibody elimination. Immune tolerance induction (ITI) is the only clinically established approach for developing antigen-specific tolerance to FVIII. This work aims to establish a novel cost-effective strategy to produce FVIII molecules in fusion with cholera toxin B (CTB) subunit at the N terminus using the Bacillus subtilis expression system for oral tolerance, as the current clinical immune tolerance protocols are expensive. Regions of B-Domain Deleted (BDD)-FVIII that have potential epitopes were identified by employing Bepipred linear epitope prediction; 2 or more epitopes in each domain were combined and cDNA encoding these regions were fused with CTB and cloned in the Bacillus subtilis expression vector pHT43 and expression analysis was carried out. The expressed CTB-fused FVIII epitope domains showed strong binding affinity towards the CTB-receptor GM1 ganglioside. To conclude, Bacillus subtilis expressing FVIII molecules might be a promising candidate for exploring for the induction of oral immune tolerance.

Long-Term Efficacy and Safety of Damoctocog Alfa Pegol Prophylaxis in Patients with Haemophilia A Aged 12-<18 Years at Enrolment into PROTECT VIII.

INTRODUCTION: The phase 2/3 PROTECT VIII study demonstrated long-term efficacy and safety of damoctocog alfa pegol (BAY 94-9027; Jivi®), a B-domain-deleted recombinant factor VIII (FVIII), site-specifically PEGylated to improve its pharmacokinetic profile. We report a post hoc assessment of bleeding and safety outcomes in the subgroup of patients, aged 12-<18 years at enrolment. METHOD: PROTECT VIII was a multicentre, open-label study of previously treated males aged 12-65 years with severe haemophilia A (FVIII <1%). Twelve patients were included in this analysis. All received damoctocog alfa pegol prophylaxis for the total time in study (median [range] time in study 4.0 [1.3-6.2] years). RESULTS: Overall median (Q1; Q3) total and joint annualised bleeding rates were 1.8 (0.4; 5.1) and 0.7 (0.2; 1.8), respectively, for the entire study. During the last 6 months of treatment, eight (66.7%) and ten (83.3%) out of 12 patients experienced zero total and joint bleeds, respectively. No patient developed FVIII inhibitors. No deaths or thrombotic events were reported. CONCLUSION: Efficacy and safety of damoctocog alfa pegol were confirmed in adolescent patients with haemophilia A, with data for up to 6 years supporting its use as a long-term treatment option in this group as they transition into adulthood.

Predicting joint involvement through tailored prophylaxis in severe haemophilia A, is it possible?

INTRODUCTION: Tailored prophylaxis is the current treatment regimen for patients with severe haemophilia A. Recently, published guidelines describe two possible approaches, based on clinical characteristics or estimation of pharmacokinetic parameters. However, both have strengths and weaknesses, and their characteristics need to be integrated to optimize treatment appropriately. In this paper, we present a model that considers together the characteristics of prophylaxis and the relevance of each. METHODS: The age at initiation of prophylaxis, number of bleeding events, treatment regimen, therapeutic adherence, FVIII trough levels, and joint status were analyzed in 59 patients followed at La Paz University Hospital between January 2000 and December 2019. RESULTS: The mean duration of primary prophylaxis of 113.37 ± 57.79 months. Eighty-three percent (n = 49) had no joint status involvement at the end of follow-up (HJHS and HEAD-US = 0). The median ABR was 0.7 (IQR 0.2 -1.0) and 54.2% presented trough levels of FVIII during follow-up >1 IU/dL. 72,9% engaged in some type of physical activity and overall adherence was over 85% in all patients evaluated. The regression analysis performed, considering all these factors, showed that the initiation of prophylaxis before 21 months of age was the most relevant protective factor against the appearance of joint involvement (OR 88.33 p.031 CI 95% 1.49-5224.40) CONCLUSION: Early initiation of prophylaxis was the most relevant factor in the protection of joint status. More comprehensive analysis models adapted to the characteristics of each population, are needed to adequately individualize treatment.

Mutational landscape, inhibitor development, and health-care burden in non-severe haemophilia A: A single-centre Australian experience.

AIM: To characterise non-severe haemophilia A (HA) patients enrolled on the Australian Bleeding Disorders Registry (ABDR) treated through a state-wide Haemophilia Treatment Centre (HTC) with respect to their mutational profile, inhibitor risk and health-care burden. METHOD: We conducted a single-centre observational study of all non-severe HA patients treated at the Alfred Health HTC registered on the ABDR as of the 26th July 2023. Data were extracted from the ABDR and electronic medical record (EMR) regarding demographics, severity, genetic testing, treatment, inhibitors, bleeding events and procedures. Inhibitor risk was calculated as a function of exposure days (EDs) of FVIII replacement. RESULTS: There were 289 non-severe HA patients treated at the Alfred HTC registered on the ABDR as of July 2023, all of whom were adult patients aged > 18 years old. Genotyping had been performed in 228/289 (78.9%). Of the inhibitor analysis population, 14/193 (7.3%) had an inhibitor. The cumulative incidence of inhibitor development at 75 EDs was 31% (95% CI 13%-46%). The median cost of bypassing agents per inhibitor patient was $57,087.50/year. CONCLUSION: These results demonstrate a relatively high inhibitor prevalence and incidence risk in non-severe HA compared to previously published work, although this may partly reflect a smaller population size. High rates of genotyping have allowed representative mutational characterisation. The burden of care imposed by non-severe HA in terms of bleeding events, procedures and bypassing agent cost is larger than expected, particularly within the inhibitor population.