Three-year outcomes of valoctocogene roxaparvovec gene therapy for hemophilia A.

BACKGROUND: Valoctocogene roxaparvovec transfers a human factor (F)VIII coding sequence into hepatocytes of people with severe hemophilia A to provide bleeding protection. OBJECTIVES: To present 3-year efficacy and safety in the multicenter, open-label, single-arm, phase 3 GENEr8-1 trial. METHODS: GENEr8-1 enrolled 134 adult males with severe hemophilia A who were receiving FVIII prophylaxis. Efficacy endpoints included annualized bleeding rate, annualized FVIII utilization, FVIII activity (chromogenic substrate assay; imputed as 1 IU/dL at baseline and 0 IU/dL after discontinuation), and the Haemophilia-Specific Quality of Life Questionnaire for Adults. Safety was assessed by adverse events (AEs). RESULTS: At week 156, 131 of 134 participants remained in the study; overall, 17 of 134 resumed prophylaxis. Mean annualized bleeding rate for treated bleeds decreased from 4.8 (SD, 6.5) bleeds/y at baseline to 0.8 (SD, 2.3; P < .0001) bleeds/y after prophylaxis (prophylaxis cessation to last follow-up) and 0.97 (SD, 3.48) bleeds/y during year 3. Annualized FVIII utilization decreased 96.8% from baseline after prophylaxis and 94.2% during year 3. At week 156, mean and median FVIII activity were 18.4 (SD, 30.8) and 8.3 IU/dL, respectively. FVIII activity decrease was lower between years 2 and 3 than between years 1 and 2. At the end of year 3, clinically meaningful improvements in the Haemophilia-Specific Quality of Life Questionnaire for Adults Total Score were observed (mean change from baseline, 6.6; 95% CI, 4.24-8.87; P < .0001). Mild alanine aminotransferase elevations remained the most common AE during year 3 (23.7% of participants). A serious AE of B-cell acute lymphoblastic leukemia was considered unrelated to treatment. CONCLUSION: Hemostatic efficacy was maintained, and safety remained unchanged from previous years.

Discrepant low von Willebrand factor activity results on the ACL TOP analyzer are frequent in unselected patients with myeloproliferative neoplasms and show no correlation with high-molecular-weight multimer loss or bleeding phenotype.

BACKGROUND: Bleeding complications are common in patients with myeloproliferative neoplasms (MPNs), with a subset developing acquired von Willebrand disease. Despite this association, a wide spectrum of von Willebrand factor (VWF) abnormalities are described, and the performance of modern assays remains unclear. OBJECTIVES: To comprehensively describe the pattern of VWF laboratory abnormalities in the MPN population. METHODS: We collected samples from 74 unselected clinic patients with MPNs to evaluate VWF quantitatively and qualitatively via multiple methods, correlating findings with a retrospective analysis of clinical bleeding data. VWF assays were performed on both ACL TOP (Instrumentation Laboratory) and Acustar (Instrumentation Laboratory) analyzers using HemosIL reagents (Instrumentation Laboratory), along with multimer analysis by gel electrophoresis. RESULTS: Functional VWF measurements were not concordant between assays, with a median ACL TOP VWF glycoprotein IbR to antigen ratio (VWF:GPIbR/VWF:Ag) of 0.57 (IQR, 0.43-0.71) compared to a median Acustar VWF:GPIbR/VWF:Ag of 0.91 (IQR: 0.82-1.03;P < .001). The ACL TOP showed disproportionately lower results, with 73% of patients having a ratio <0.7. Despite this, no patient experienced loss of high-molecular-weight multimers by gel electrophoresis. An inverse relationship was observed between platelet count and functional ratios on both ACL TOP (R2 = 0.20; P < .001) and Acustar (R2 = 0.18; P = .0011) analyzers. While clinically significant bleeding events were relatively common (11% patients), there was no association with VWF assay abnormalities, and generally, an alternate cause(s) was identified. CONCLUSION: Discrepancies in functional VWF assays are common in patients with MPN, particularly by ACL TOP VWF:GPIbR. Based on our limited series, a VWF functional to an antigenic ratio of <0.7 ("type 2 pattern") alone is poorly predictive of bleeding risk.

Does the method of telehealth delivery affect the physiotherapy management of adults with bleeding disorders? A comparison of audioconferencing and videoconferencing.

AIM: To determine whether the method of telehealth delivery (audioconferencing or videoconferencing) affects the physiotherapy management of adults with inherited bleeding disorders. METHODS: A cross-sectional observational study was utilised involving 40 physiotherapy consultations (23 initial consultations and 17 follow-up consultations) of adults (>18) with a diagnosed bleeding disorder. Each consultation involved an initial audioconferencing component followed immediately by a separate videoconferencing component. Following each component, the physiotherapist utilised the clinical information gathered to formulate and record a management plan, and additionally recorded their confidence in this plan. Differences between the management plans and clinician confidence were recorded, including where applicable the visual information prompting a change in management plans. RESULTS: Audioconferencing and videoconferencing management plans differed in 40% of all consultations, including 52.0% of initial consultations and 23.5% of follow-up consultations. Among consultations where management plans differed, this was prompted by visual information related to the anatomic location of symptoms (31.3%), the absence/presence of swelling (31.3%), joint range of movement (25.0%), and general appearance (12.5%). Median self-reported clinician confidence of management plans increased significantly from 70.0% following audioconferencing to 93.0% following videoconferencing. CONCLUSION: When utilizing telehealth, the choice between audioconferencing or videoconferencing may affect physiotherapy management of adults with bleeding disorders, particularly with initial consultations. Videoconferencing potentially leads to more appropriate management plans, clinician confidence and utilization of healthcare resources. Further high-quality studies are required to confirm the findings of this study.

Two-Year Outcomes of Valoctocogene Roxaparvovec Therapy for Hemophilia A.

BACKGROUND: Valoctocogene roxaparvovec delivers a B-domain-deleted factor VIII coding sequence with an adeno-associated virus vector to prevent bleeding in persons with severe hemophilia A. The findings of a phase 3 study of the efficacy and safety of valoctocogene roxaparvovec therapy evaluated after 52 weeks in men with severe hemophilia A have been published previously. METHODS: We conducted an open-label, single-group, multicenter, phase 3 trial in which 134 men with severe hemophilia A who were receiving factor VIII prophylaxis received a single infusion of 6×1013 vector genomes of valoctocogene roxaparvovec per kilogram of body weight. The primary end point was the change from baseline in the annualized rate of treated bleeding events at week 104 after receipt of the infusion. The pharmacokinetics of valoctocogene roxaparvovec were modeled to estimate the bleeding risk relative to the activity of transgene-derived factor VIII. RESULTS: At week 104, a total of 132 participants, including 112 with data that were prospectively collected at baseline, remained in the study. The mean annualized treated bleeding rate decreased by 84.5% from baseline (P<0.001) among the participants. From week 76 onward, the trajectory of the transgene-derived factor VIII activity showed first-order elimination kinetics; the model-estimated typical half-life of the transgene-derived factor VIII production system was 123 weeks (95% confidence interval, 84 to 232). The risk of joint bleeding was estimated among the trial participants; at a transgene-derived factor VIII level of 5 IU per deciliter measured with chromogenic assay, we expected that participants would have 1.0 episode of joint bleeding per year. At 2 years postinfusion, no new safety signals had emerged and no new serious adverse events related to treatment had occurred. CONCLUSIONS: The study data show the durability of factor VIII activity and bleeding reduction and the safety profile of valoctocogene roxaparvovec at least 2 years after the gene transfer. Models of the risk of joint bleeding suggest that the relationship between transgene-derived factor VIII activity and bleeding episodes is similar to that reported with the use of epidemiologic data for persons with mild-to-moderate hemophilia A. (Funded by BioMarin Pharmaceutical; GENEr8-1 ClinicalTrials.gov number, NCT03370913.).

A low-dose rituximab regimen for first-line treatment of acquired haemophilia A.

A low-dose rituximab regimen for first-line treatment of acquired haemophilia A. INTRODUCTION: Acquired haemophilia A (AHA) is a rare disease caused by the development of autoantibodies against FVIII. Diagnosis involves confirmation of FVIII deficiency and the presence of an inhibitor via the Bethesda assay. Severe bleeding is often managed with bypassing agents such as recombinant factor VII. This is then followed by eradication of the inhibitor with immunosuppression which typically includes a corticosteroid backbone. AIM: Review the current management and outcomes of AHA in Queensland, Australia. Determine the incidence, demographics and clinical characteristics of AHA patients. METHODS: Retrospective case series of AHA diagnosed between May 2014 and August 2018. Data were derived from the Australian Bleeding Disorders Registry and state-wide pathology database. Data collection proforma was completed by the treating haematologist and reviewed/compiled centrally. RESULTS: 24 patients were identified (incidence 1 in 1.27 million). The median age was 76.5 years. Median follow-up was 20 months. Index bleed was atraumatic and skin/soft tissue in the majority of patients. Recombinant FVIIa was the most commonly used haemostatic therapy and effective in 85% of patients. Immunosuppression and steroid usage were uniform. Upfront second agent was used in 75% of patients and was most commonly rituximab. 87.5% of patients achieved a complete remission in a median time of 48 days. Low-dose rituximab was frequently used and equally as efficacious as standard dose. CONCLUSION: Immunosuppression with combination therapy, notably rituximab, appears to be non-inferior and has a favourable side effect profile.

Emicizumab prophylaxis in infants with severe haemophilia A without inhibitors: Illustrative real-world cases to support shared decision-making.

INTRODUCTION: Emicizumab has been shown to be safe and effective for prevention of bleeds in patients with severe haemophilia A (SHA), both with and without inhibitors. The subcutaneous administration and long half-life make emicizumab an attractive option for prophylaxis in infants with SHA, however data to inform treatment decisions in this younger age group are almost absent. AIM: The aim of this report is to share real world experience to illustrate how the availability of emicizumab has shifted the prophylaxis paradigm in the management of infants with SHA. METHOD: We selected four cases from our own cohort of infants with SHA to outline the rationale for emicizumab prophylaxis in a range of scenarios familiar to paediatric haemophilia treaters. RESULTS: In Case 1 emicizumab was commenced at 7 days following initial treatment of neonatal ICH with a FVIII infusion. In Case 2 emicizumab was commenced at 5 weeks due to parental anxiety regarding the potential for ICH during infancy. Case 3 commenced emicizumab at 15 months in lieu of standard primary prophylaxis. Case 4 switched to emicizumab prophylaxis at 14 months after a period of primary prophylaxis with FVIII concentrates to alleviate parental anxiety regarding future inhibitor development. No patient had any bleeding events after commencement of emicizumab (median follow up 12 months), and no drug-related adverse effects were observed. CONCLUSION: Despite the paucity of data in infants with SHA the potential role of emicizumab prophylaxis should be discussed with families when clinically relevant, with decisions tailored to individual need.

Acquired haemophilia and haemostatic control with recombinant porcine factor VIII: case series.

BACKGROUND: Acquired haemophilia A (AHA) is a rare acquired bleeding disorder that can present with life-threatening bleeding. AIMS: To describe recent Australian use of recombinant porcine factor VIII (rpFVIII) replacement therapy as a haemostatic agent in patients with acquired haemophilia. METHODS: Four patients with acquired haemophilia treated in three different institutions around Australia in the past 12 months were included in the study. Haemostatic efficacy of Obizur (Takeda) was assigned by the treating haematologist according to previously published criteria. RESULTS: Six bleeds were treated with rpFVIII, three of which were initially refractory to treatment with recombinant VIIa. rpFVIII was rated efficacious in 100% of bleeds by 24 h. rpFVIII loading dose was 100 U/kg (100-120 U kg-1 ) and this increased the factor VIII level (via one-stage FVIII assay) from <1-1.2% to 54-306% taken 0.5-1.5 h post-infusion. Subsequent doses ranged from 40 to 60 U/kg twice daily or daily for 3 to 13 days. No rpFVIII related adverse events occurred. Three of the four patients achieved complete remission and were weaned from immunosuppression. One patient died prior to achieving partial remission, secondary to an arterial ischaemic event. CONCLUSION: This case series demonstrates that recombinant porcine FVIII is efficacious to treat acute bleeds in acquired haemophilia, including in those who are refractory to bypassing agents. Doses of rpFVIII were able to be titrated based on FVIII level and clinical response.

Bleeding Disorders in Adolescents with Heavy Menstrual Bleeding: The Queensland Statewide Paediatric and Adolescent Gynaecology Service.

STUDY OBJECTIVE: Heavy menstrual bleeding (HMB) is a common gynecological complaint among young women with up to 40% having experienced HMB. Bleeding disorders are increasingly being recognized in adolescents and young adults with HMB. The aim of this study was to determine the prevalence of bleeding disorders in adolescents with HMB, among patients who presented to the Queensland Statewide Paediatric and Adolescent Gynaecology Service between July 2007 and July 2017. DESIGN, SETTING, PARTICIPANTS, INTERVENTIONS, AND MAIN OUTCOME MEASURES: The study was a retrospective review of 124 female adolescents aged 8 to 18 years with HMB who presented to the Queensland Paediatric and Adolescent Gynaecology Service, Brisbane, Australia. The primary outcome measure was diagnosis of a bleeding disorder, with secondary outcomes including iron deficiency and/or anemia and treatment modalities. RESULTS: Screening for bleeding disorders was performed in 77/124 (62.1%) of patients with HMB. Twenty-seven adolescents were diagnosed with a bleeding disorder, giving a prevalence of 27/124 (21.7%) in those with HMB, and 27/77 (35%) with HMB who were screened. Of these 35%, von Willebrand disease was the most common bleeding disorder, found in 14/27 (51.6%), followed by inherited platelet function disorders diagnosed in 9/27 (33.3%), thrombocytopenia (inherited or acquired) in 3/27 (11.1%), and Factor IX deficiency in 1/27 (3.7%). Iron deficiency and/or anemia was diagnosed in 53/107 (49.5%) of patients with HMB who were screened for this, and 19/27 (70.3%) of those diagnosed with a bleeding disorder. CONCLUSION: Adolescents with HMB who present to a tertiary pediatric and adolescent gynecology service should be screened for bleeding disorders, because of the considerably high prevalence in this at-risk population.

Demonstration of a novel Xp22.2 microdeletion as the cause of familial extreme skewing of X-inactivation utilizing case-parent trio SNP microarray analysis.

BACKGROUND: We report a kindred referred for molecular investigation of severe hemophilia A in a young female in which extremely skewed X-inactivation was observed in both the proband and her clinically normal mother. METHODS: Bidirectional Sanger sequencing of all F8 gene coding regions and exon/intron boundaries was undertaken. Methylation-sensitive restriction enzymes were utilized to investigate skewed X-inactivation using both a classical human androgen receptor (HUMARA) assay, and a novel method targeting differential methylation patterns in multiple informative X-chromosome SNPs. Illumina Whole-Genome Infinium microarray analysis was performed in the case-parent trio (proband and both parents), and the proband's maternal grandmother. RESULTS: The proband was a cytogenetically normal female with severe hemophilia A resulting from a heterozygous F8 pathogenic variant inherited from her similarly affected father. No F8 mutation was identified in the proband's mother, however, both the proband and her mother both demonstrated completely skewed X-chromosome inactivation (100%) in association with a previously unreported 2.3 Mb deletion at Xp22.2. At least three disease-associated genes (FANCB, AP1S2, and PIGA) were contained within the deleted region. CONCLUSIONS: We hypothesize that true "extreme" skewing of X-inactivation (≥95%) is a rare occurrence, but when defined correctly there is a high probability of finding an X-chromosome disease-causing variant or larger deletion resulting in X-inactivation through a survival disadvantage or cell lethal mechanism. We postulate that the 2.3 Mb Xp22.2 deletion identified in our kindred arose de novo in the proband's mother (on the grandfather's homolog), and produced extreme skewing of X-inactivation via a "cell lethal" mechanism. We introduce a novel multitarget approach for X-inactivation analysis using multiple informative differentially methylated SNPs, as an alternative to the classical single locus (HUMARA) method. We propose that for females with unexplained severe phenotypic expression of an X-linked recessive disorder trio-SNP microarray should be undertaken in combination with X-inactivation analysis.

Anaphylaxis Following Human Prothrombin Complex Concentrate in a Child with Lupus Anticoagulant Hypoprothrombinemia Syndrome: A Cautionary Tale.

A previously healthy 3-year-old girl presented with a short history of mucocutaneous bleeding and a spontaneous left knee hemarthrosis following a nonspecific viral gastroenteritis. Initial investigations for a bleeding disorder revealed a normal platelet count; however, coagulation studies revealed a prothrombin time (PT) of 25 seconds and an activated partial thromboplastin time (APTT) of 66 seconds (both prolonged). The APTT did not correct on mixing with normal plasma, and further testing confirmed the presence of a strong lupus anticoagulant (LA). One-stage assays of factor VIII, VII, and X were normal, but factor II was markedly reduced. Based on this distinct clinicopathological picture, a diagnosis of lupus anticoagulant hypoprothrombinemia syndrome (LAHS) was made. Due to the presence of a hemarthrosis, the patient was treated with clotting factor concentrate. Human prothrombin complex concentrate (PROTHROMBINEX-VF) was used as a source of factor II replacement; however, during the infusion the patient developed anaphylaxis necessitating resuscitation. The patient was observed without further factor replacement, and the bleeding symptoms resolved over several days. Within 3 weeks her PT and factor II had normalized but the APTT remained prolonged. After 6 months the coagulation profile had completely normalized and the LA was negative. It is unusual to require replacement of factor II in paediatric LAHS because bleeding is typically minor and self-limited. Anaphylaxis to clotting factor concentrates has not been previously reported in the context of LAHS, but is well described in patients with congenital factor IX deficiency (hemophilia B). Whilst the potential mechanism for anaphylaxis in our patient is unknown, it is recommended that human prothrombin complex concentrates should be used cautiously in paediatric LAHS.

Prospective observational cohort study of Health Related Quality of Life (HRQOL), chronic foot problems and their determinants in gout: a research protocol.

BACKGROUND: Gout is the commonest inflammatory arthritis affecting around 1.4% of adults in Europe. It is predominantly managed in primary care and classically affects the joints of the foot, particularly the first metatarsophalangeal joint. Gout related factors (including disease characteristics and treatment) as well as comorbid chronic disease are associated with poor Health Related Quality of Life (HRQOL) yet to date there is limited evidence concerning gout in a community setting. Existing epidemiological studies are limited by their cross-sectional design, selection of secondary care patients with atypical disease and the use of generic tools to measure HRQOL. This 3 year primary care-based prospective observational cohort study will describe the spectrum of HRQOL in community dwelling patients with gout, associated factors, predictors of poor outcome, and prevalence and incidence of foot problems in gout patients. METHODS: Adults aged ≥ 18 years diagnosed with gout or prescribed colchicine or allopurinol in the preceding 2 years will be identified through Read codes and mailed a series of self-completion postal questionnaires over a 3-year period. Consenting participants will have their general practice medical records reviewed. DISCUSSION: This is the first prospective cohort study of HRQOL in patients with gout in primary care in the UK. The combination of survey data and medical record review will allow an in-depth understanding of factors that are associated with and lead to poor HRQOL and foot problems in gout. Identification of these factors will improve the management of this prevalent, yet under-treated, condition in primary care.