Hemostatic balance between pro- and anticoagulant is maintained during glucocorticoid treatment.

BACKGROUND: Glucocorticoids are associated with an increased risk of venous thrombosis. Glucocorticoid treatment increases coagulation factor and anticoagulant levels; however, its effect on hemostatic function remains unclear. This study aimed to investigate the changes in comprehensive coagulation profiles after glucocorticoid treatment in noninflammatory diseases to elucidate the direct contribution of glucocorticoids to hemostatic function. PROCEDURE: Patients diagnosed with primary immune thrombocytopenia requiring glucocorticoid treatment were prospectively enrolled in this study. Changes in coagulation factors and anticoagulants during glucocorticoid treatment and changes in thrombin generation potential were determined in the absence and presence of soluble thrombomodulin (sTM). RESULTS: Seven treatment cases (four for steroid pulse therapy and three for oral glucocorticoid therapy) in six patients with immune thrombocytopenia were examined. After glucocorticoid treatment, activated partial thromboplastin time significantly shortened, and activities of factor VIII, IX, XI, and XII significantly increased, except for von Willebrand factor antigen. Moreover, antithrombin and protein C (PC) activities significantly increased after glucocorticoid treatment. Two major parameters of thrombin generation potential, endogenous thrombin potential (ETP) and peak thrombin (Peak), significantly increased in the absence of sTM after glucocorticoid treatment. However, no significant increases in either parameter were observed in the presence of sTM. ETP-TM and Peak-TM ratios, which represent resistance to the anticoagulant effect of the PC pathway, significantly decreased after glucocorticoid treatment, suggesting that anticoagulant function via the PC pathway is elevated after glucocorticoid treatment. CONCLUSIONS: As glucocorticoids increase intrinsic coagulation factor and anticoagulant levels, hemostatic balance between pro- and anticoagulant functions is maintained.

Plasma-derived factor VIIa and factor X mixture agent (MC710) prophylaxis in haemophilia B patients with inhibitors.

INTRODUCTION: Haemophilia B patients with factor IX inhibitors have particularly unmet needs for conventional therapy. AIM: Phase II/III clinical trial, multicentre, open-label, prospective, self-controlled study was conducted to assess MC710 prophylaxis in haemophilia B patients with inhibitors. METHODS: We enrolled haemophilia patients who had received episodic or prophylactic treatment with bypassing agents up to that time. The participants continued their conventional therapy for 24 weeks and then MC710 was prophylactically infused intravenously every 2 or 3 days at 60 to 120 µg as FVIIa per kilogram of body weight for 24 weeks. The primary endpoint was the annual bleeding rate (ABR) requiring bypassing agents, which was compared intraindividually between the conventional therapy period and the MC710 prophylaxis period. RESULTS: A total of 11 male haemophilia B patients were enrolled. The median ABR ratio for each participant (the prophylaxis period ABR divided by the conventional therapy period ABR) was .33 (2.1/6.5), range from .00 to 3.77. ABR ratios for 9 of the 11 patients ranged from .00 to .60, and 3 of the 9 patients had zero bleeding events during the prophylaxis period. Meanwhile, ABR ratios for the remaining two patients were 2.53 and 3.77, respectively. Although a fibrinogen decrease recovered by the dose reduction was reported for only one participant as the sole adverse drug reaction in this study, no thrombotic events or other safety concerns were reported. CONCLUSION: MC710 prophylaxis is considered to be decrease the bleeding rate in haemophilia B patients with inhibitors without safety concerns.

The seroprevalence of neutralizing antibodies against the adeno-associated virus capsids in Japanese hemophiliacs.

Adeno-associated virus (AAV) vectors are promising modalities of gene therapy to address unmet medical needs. However, anti-AAV neutralizing antibodies (NAbs) hamper the vector-mediated therapeutic effect. Therefore, NAb prevalence in the target population is vital in designing clinical trials with AAV vectors. Hence, updating the seroprevalence of anti-AAV NAbs, herein we analyzed sera from 100 healthy individuals and 216 hemophiliacs in Japan. In both groups, the overall seroprevalence against various AAV serotypes was 20%-30%, and the ratio of the NAb-positive population increased with age. The seroprevalence did not differ between healthy participants and hemophiliacs and was not biased by the concomitant blood-borne viral infections. The high neutralizing activity, which strongly inhibits the transduction with all serotypes in vitro, was mostly found in people in their 60s or of older age. The multivariate analysis suggested that "60s or older age" was the only independent factor related to the high titer of NAbs. Conversely, a large proportion of younger hemophiliacs was seronegative, rendering them eligible for AAV-mediated gene therapy in Japan. Compared with our previous study, the peak of seroprevalences has shifted to older populations, indicating that natural AAV exposure in the elderly occurred in their youth but not during the last decade.

Clinical and pathophysiological delineation of musculocontractural Ehlers-Danlos syndrome caused by dermatan sulfate epimerase deficiency (mcEDS-DSE): A detailed and comprehensive glycobiological and pathological investigation in a novel patient.

Musculocontractural Ehlers-Danlos syndrome caused by dermatan sulfate epimerase deficiency (mcEDS-DSE) is a rare connective tissue disorder. This is the first report describing the detailed and comprehensive clinical and pathophysiological features of mcEDS-DSE. The patient, with a novel homozygous nonsense variant (NM_013352.4:c.2601C>A:p.(Tyr867*)), exhibited mild skin hyperextensibility without fragility and small joint hypermobility, but developed recurrent large subcutaneous hematomas. Dermatan sulfate (DS) moieties on chondroitin sulfate/DS proteoglycans were significantly decreased, but remained present, in skin fibroblasts. Electron microscopy examination of skin specimens, including cupromeronic blue-staining to visualize glycosaminoglycan (GAG) chains, revealed coexistence of normally assembled collagen fibrils with attached curved GAG chains and dispersed collagen fibrils with linear GAG chains from attached collagen fibrils across interfibrillar spaces to adjacent fibrils. Residual activity of DS-epi1, encoded by DSE, and/or compensation by DS-epi2, a minor homolog of DS-epi1, may contribute to the mild skin involvement through this "mosaic" pattern of collagen fibril assembly.

AOZORA: long-term safety and joint health in paediatric persons with haemophilia A without factor VIII inhibitors receiving emicizumab - protocol for a multicentre, open-label, phase IV clinical study.

INTRODUCTION: Persons with haemophilia A (PwHA) commonly experience regular bleeding into joints, which may result in joint damage and complications such as degenerative arthritis. Emicizumab has previously demonstrated efficacy in reducing the occurrence of joint bleeds and target joints, along with having a favourable safety profile; however, data on the long-term effects on joint health are lacking. The AOZORA study will evaluate the long-term safety and joint health of paediatric PwHA without factor (F)VIII inhibitors taking emicizumab; here, we report the details of the study protocol and baseline data. METHODS AND ANALYSIS: AOZORA is a multicentre, open-label, phase IV clinical study in Japan that aims to enrol approximately 30 PwHA aged <12 years without FVIII inhibitors. The primary endpoints include a long-term safety evaluation of adverse events, laboratory test abnormalities and FVIII inhibitor development; and a long-term joint health assessment using MRI and the Hemophilia Joint Health Score. Exploratory endpoints include characterising participants' physical activities and the number of activity-related bleeds requiring coagulation factor treatment. Currently, 30 participants have been enrolled, including 20 emicizumab-naïve participants and 10 who transferred from HOHOEMI, a previous study in paediatric PwHA. ETHICS AND DISSEMINATION: The AOZORA study was approved by the Institutional Review Boards of Nara Medical University and the St Marianna University Group. The study will be conducted in compliance with the Declaration of Helsinki, the standards stipulated in paragraph 3 of Article 14 and Article 80-2 of the Pharmaceuticals, Medical Devices and Other Therapeutic Products Act, the Ministerial Ordinance on Good Clinical Practice and the Ministerial Ordinance on Good Post-marketing Study Practice. Data will be published in peer-reviewed journals and presented at Global congresses. TRIAL REGISTRATION NUMBER: JapicCTI-194701.

Clinical conditions and risk factors for inhibitor-development in patients with haemophilia: A decade-long prospective cohort study in Japan, J-HIS2 (Japan Hemophilia Inhibitor Study 2).

BACKGROUND: Inhibitor-development is a serious complication in patients with haemophilia (PwH). Previous studies reported that therapeutic and genetic factors could be associated with these alloantibodies. Relevant clinical features such as genetic-background and different treatment regimens in Japan remain unclear, however. AIMS: To analyse a nation-wide Japanese registry for PwH, and to examine risk factors for inhibitor-development. METHODS AND RESULTS: Newly diagnosed patients with haemophilia A (PwHA) or haemophilia B (PwHB) without inhibitors after 2007, and with treatment records traceable from 0 to 75 exposure days (ED), were enrolled in the Japan Hemophilia Inhibitor Study 2 (J-HIS2) initiated in 2008. Of 417 patients (340 PwHA, 77 PwHB) from 46 facilities, 83 (76 PwHA, 7 PwHB) were recorded with inhibitors by July 2020. Inhibitors were observed in 31.0% of severe PwHA, 8.0% moderate and 1.6% mild and in 17.1% of severe PwHB. The majority of inhibitors (89.7% in severe PwHA and 71.4% in severe PwHB) were detected on or before 25ED (median 12ED in PwHA and 19ED in PwHB). Genotyping in these severe patients identified an association between inhibitor-development and null variants of F8 (P < .01) or F9 (P < .05). A lower incidence of inhibitors was recorded in severe PwHA treated with prophylaxis than in those treated on-demand (P < .01). A past-history of intracranial-haemorrhage appeared to be associated with inhibitor-development, while FVIII-concentrates infusion and routine vaccination on the same day was not related to inhibitor-development. CONCLUSION: The J-HIS2 study has identified significant clinical variables associated with inhibitor-development in Japanese PwH, consistent with other global studies.

Assessment of global coagulation function under treatment with emicizumab concomitantly with bypassing agents in haemophilia A with inhibitor (UNEBI Study): multicentre open-label non-randomised clinical trial.

INTRODUCTION: Subcutaneous emicizumab prophylaxis substantially reduces bleeding episodes in patients with haemophilia A (PwHA) and factor VIII inhibitor. However, thrombotic events occurred in some PwHA with inhibitor who had received high cumulative doses of activated prothrombin complex concentrates at their breakthrough bleeds, when they were also given prophylactic emicizumab. After that, although the recommended guidance was proposed for bypassing agents (BPAs) therapy under emicizumab prophylaxis for haemostatic management, detailed investigation(s) is(are) required to elucidate the safe and appropriate dose of BPAs to use concomitantly with emicizumab prophylaxis. METHODS AND ANALYSIS: In the UNEBI Study, 60 PwHA with inhibitor will be enrolled for a maximum duration of 3 years, and samples of 20 events following concomitant use of BPAs with emicizumab will be collected. An 'event' is defined as obtaining blood samples before and after administration of BPA when a breakthrough bleed or a surgical procedure occurs. The coagulation potential in the obtained samples will be measured by global coagulation assays. The primary endpoint is the degree of improvement in the maximum coagulation rate by clot waveform analysis (CWA) before and after administration of fixed-dose BPAs. This parameter obtained from CWA, which is triggered with an optimally diluted mixture of prothrombin time/activated partial thromboplastin time-reagents, is reported to be an excellent marker for assessing the degree of improvement in coagulation potential in emicizumab-treated plasma. ETHICS AND DISSEMINATION: The UNEBI Study was approved by the Japan Certified Review Board of Nara Medical University. The results of the study will be communicated through publication in international scientific journals and presentations at (inter)national conferences. TRIAL REGISTRATION NUMBER: jRCTs051190119.

Spectrum of F8 Genotype and Genetic Impact on Inhibitor Development in Patients with Hemophilia A from Multicenter Cohort Studies (J-HIS) in Japan.

Some genetic and treatment-related factors are risk factors for inhibitor development in patients with hemophilia A (PwHA). However, the genotype distribution of the factor VIII gene (F8) and genetic impact on inhibitor development in Japanese PwHA remain unknown. In 2007, the Japan Hemophilia Inhibitor Study 2 (J-HIS2) was organized to establish a nationwide registry system for hemophiliacs and to elucidate risk factors for inhibitor development, designed for prospective investigation following a retrospective study (J-HIS1) which had already finished. Patients, newly diagnosed after January 2007, were enrolled in J-HIS2 and followed up for inhibitor development and clinical environments since 2008 onward. In the present study, F8 genotypes of PwHA were investigated in the patients recruited from the J-HIS2 cohort as well as those with inhibitor from the J-HIS1 cohort. F8 variants identified in 59 PwHA with inhibitor in J-HIS1 were: 20 intron-22 inversions, 5 intron-1 inversions, 9 large deletions, 4 nonsense, 8 missense, 11 small in/del, and 2 splice-site variants. F8 variants identified in 267 (67 with inhibitor) PwHA in J-HIS2 were: 76(28) intron-22 inversions, 3(2) intron-1 inversion, 1(0) duplication, 8(5) large deletions, 21(7) nonsense, 109(7) missense, 40(11) small in/del, and 9(7) splice-site variants. Forty variants were novel. The cumulative inhibitor incidence rate in the severe group with null changes was 42.4% (95% confidence interval [CI]: 33.7-50.8), higher than that with nonnull changes (15.6% [95%CI: 6.8-27.8]), in J-HIS2. Relative risk for inhibitor development of null changes was 2.89. The spectrum of F8 genotype and genetic impact on inhibitor development in Japanese PwHA were consistent with the previous reports.

Long-term safety and efficacy of emicizumab for up to 5.8 years and patients' perceptions of symptoms and daily life: A phase 1/2 study in patients with severe haemophilia A.

INTRODUCTION: Safety and efficacy results of the phase 1 study and phase 1/2 extension study of the bispecific antibody emicizumab in patients with severe haemophilia A with or without factor VIII inhibitors for up to 2.8 years were reported previously. AIM: To evaluate further longer-term data including patients' perceptions at study completion. METHODS: Emicizumab was administered subcutaneously once weekly at maintenance doses of 0.3, 1 or 3 mg/kg with potential up-titration. All patients were later switched to the approved maintenance dose of 1.5 mg/kg. RESULTS: Eighteen patients received emicizumab for up to 5.8 years. Most adverse events were mild and unrelated to emicizumab. Annualized bleeding rates (ABRs) for bleeds treated with coagulation factors decreased from pre-emicizumab rates or remained zero in all patients. The median ABRs were low at 1.25, 0.83 and 0.22 during the 0.3, 1 and 3 mg/kg dosing periods, respectively. Of 8 patients who decreased their doses from 3 to 1.5 mg/kg, ABRs decreased in 4, remained at zero in 2, and increased in 2. Total time spent with symptoms associated with treated bleeds decreased in all patients except 2. All patients answered 'improved' for bleeding severity and time until bleeding stops, except 1 answering 'slightly improved'. Most patients answered 'improved' or 'slightly improved'' for daily life and feelings; in particular, all patients except 1 answered 'improved' or 'slightly improved' for anxiety. CONCLUSIONS: Long-term emicizumab prophylaxis for up to 5.8 years was safe and efficacious, and may improve patients' daily lives and feelings, regardless of inhibitor status.

Prophylaxis Using a Mixture of Plasma-Derived Activated Factor VII and Factor X (pdFVIIa/FX) in a Patient with Hemophilia B Complicated by Inhibitors and Allergy to Factor IX Concentrates: A Case Report.

Treating patients with hemophilia and inhibitors is often problematic. The presence of inhibitors negatively impacts the effectiveness of treatment to achieve hemostasis especially in patients with hemophilia B, owing mainly to allergic reactions to factor IX (FIX) concentrates and the low success rate of immune tolerance therapy. A 9-month-old boy had intracranial hemorrhage and was diagnosed with hemophilia B. After replacement therapy, he developed inhibitors and an allergic reaction to FIX. Prophylactic therapy was initiated with recombinant activated factor VII (rFVIIa) and later switched to pdFVIIa/factor X (FX; 120 µg/kg as the FVII dose, every other day) because of a recurrence of intracranial hemorrhage. Since then, he remained well without life-threatening bleeding for more than 2 years. Our case suggests that pdFVIIa/FX may be useful for prophylactic therapy in hemophilia B complicated by inhibitors and allergic reaction to FIX concentrates.

Long-Term Safety and Efficacy of Nonacog Beta Pegol (N9-GP) Administered for at Least 5 Years in Previously Treated Children with Hemophilia B.

Long-term safety and efficacy data of extended half-life factor IX (FIX) prophylaxis in children with hemophilia B (HB) are sparse. paradigm 5 is a multinational, open-label, single-arm, phase III trial assessing once-weekly (40 IU/kg) prophylactic nonacog beta pegol (N9-GP) in previously treated patients (PTPs) aged ≤ 12 years with HB (FIX activity ≤ 2%). Primary endpoint: incidence of anti-FIX inhibitory antibodies (≥ 0.6 Bethesda Units). We present a 5-year analysis (N = 25, including remaining patients with ≥ 5 years' follow-up) and compare with a 1-year analysis (≥ 52 weeks' exposure). The main phase enrolled 25 children; 22 entered the extension phase; 17 remained in trial at data cutoff. Median treatment period: 5.6 years/patient; median total number of N9-GP exposure days: 290.0/patient. No patients developed anti-FIX inhibitory antibodies. No other safety concerns, including thromboembolic events, were reported. Neurological examinations have not revealed any new abnormal findings. Sixteen (64.0%) patients remained free from spontaneous bleeds; all bleeds were mild/moderate in severity; 93.0% were controlled with 1 to 2 N9-GP injections. No intracranial hemorrhages were reported. Annualized bleeding rates (ABRs) were very low at 5 years (median/Poisson-estimated mean overall ABR: 0.66/0.99), having decreased from the 1-year analysis (1.00/1.44). Median/Poisson-estimated mean spontaneous ABRs for the 1- and 5-year analyses: 0.00/0.45 and 0.00/0.33. Mean FIX trough activity at 5 years: 17.9%. Mean polyethylene glycol plasma concentration reached steady state at 6 months, increasing slightly over time, in line with increased FIX trough activity. N9-GP administered for ≥ 5 years shows favorable long-term safety and efficacy in PTPs with HB (FIX activity ≤ 2%).

A multicentre, open-label study of emicizumab given every 2 or 4 weeks in children with severe haemophilia A without inhibitors.

INTRODUCTION: Emicizumab is a recombinant humanized bispecific monoclonal antibody mimicking the cofactor function of activated factor VIII. AIM: In this multicentre, open-label study (HOHOEMI), we evaluated the efficacy, safety and pharmacokinetics of emicizumab in Japanese paediatric patients aged <12 years with severe haemophilia A without factor VIII (FVIII) inhibitors. METHODS: Emicizumab was administered subcutaneously, with four loading doses of 3 mg/kg every week followed by maintenance doses of 3 mg/kg every 2 weeks (Q2W) or 6 mg/kg every 4 weeks (Q4W) in 6 and 7 patients, respectively. RESULTS: All patients completed at least 24 weeks of treatment. Baseline ages ranged from 4 months to 10 years, and all patients had been treated with FVIII prophylaxis prior to enrolment except a 4-month-old patient untreated with FVIII previously. In the respective Q2W and Q4W cohorts, 2/6 and 5/7 patients experienced no treated bleeding events, and annualized bleeding rates for treated bleeding events were 1.3 (95% confidence interval [CI], 0.6-2.9) and 0.7 (95% CI, 0.2-2.6). All caregivers preferred emicizumab to the patient's previous treatment. Only one related adverse event (injection site reaction) was observed. There were no thromboembolic events or thrombotic microangiopathy. Individual trough plasma concentrations of emicizumab were within the variability observed in preceding adult/adolescent studies. All patients tested negative for anti-emicizumab antibodies. CONCLUSIONS: Emicizumab administered Q2W or Q4W was efficacious and safe in paediatric patients with severe haemophilia A without inhibitors. This study was registered at http://www.clinicaltrials.jp (JapicCTI-173710).

Postmarketing safety and effectiveness of recombinant factor IX (nonacog alfa) in Japanese patients with haemophilia B.

INTRODUCTION: In 2010, nonacog alfa became the first recombinant factor IX (rFIX) available in Japan for patients with haemophilia B. AIM: To determine real-world safety (adverse events, incidence of inhibitors) and effectiveness of nonacog alfa in Japan. METHODS: This multicentre, prospective, observational, postmarketing surveillance study enrolled previously treated and untreated patients (PTPs and PUPs, respectively) who were observed for 1 and 2 years, respectively, after initiating nonacog alfa therapy. Safety and effectiveness were assessed for each treatment type. Annualized bleeding rate (ABR) and incremental recovery of rFIX were also evaluated. RESULTS: Overall, 312 of 314 patients enrolled from 173 sites were eligible for the safety analysis set (PTPs, 281; PUPs, 28; other, 3). Mean age was 25.4 (PTPs) and 14.8 (PUPs) years. Haemophilic severity ranged from mild to severe, and 133 (42.6%) patients had haemophilic arthropathy. Of 285 patients (PTPs, 257; PUPs, 28) in the effectiveness set, 112 received on-demand treatment for 1161 bleeding episodes (effectiveness rate, 93.7%) and 185 received routine prophylaxis (effectiveness rate, 95.5%). No spontaneous bleeding was observed in 52.4% of patients during prophylactic treatment. Median ABR was lower during routine prophylaxis (2.0) vs the rest of the observation period (8.3). A weak negative correlation was found between body weight and the reciprocal of rFIX recovery. Eleven adverse drug reactions occurred in 7 PTPs (2.2% [7/312]); recurrence of inhibitor was observed in 1 patient, but no new inhibitor developed in PTPs or PUPs. CONCLUSION: Nonacog alfa therapy is safe and effective in the real-world scenario in Japan.

Inhibitor development, safety and efficacy of Advate® among previously treated patients with hemophilia A in a postmarketing surveillance in Japan.

Rurioctocog alfa (recombinant factor VIII: Advate®) is available for the control of bleeding in patients with hemophilia A in Japan. To evaluate the inhibitor development, safety, and efficacy of rurioctocog alfa, a non-interventional and observational postmarketing surveillance was conducted on 352 previously treated Japanese patients aged 1-76 years with ≥ 4 exposure days under the conditions of routine clinical practice. A post-hoc comparison of the mean annualized bleeding rates which required treatment with rurioctocog alfa detected a statistically significant difference (P < 0.0001) between patients treated on regular prophylaxis (8.5 bleeds/year) and patients treated on an on-demand basis (36.6 bleeds/year). Favorable prophylactic and on-demand hemostatic efficacy ("excellent" or "good") were shown in 88.5-100% of patients across all treatment regimens. A total of 22 events of adverse drug reactions were reported in 13 male patients. Of the 352 patients, 3 (0.9%) patients, all of whom had ≤ 50 exposure days before enrollment, developed de novo FVIII inhibitor. No deaths or allergic reactions were reported. Rurioctocog alfa was found to be well-tolerated and effective among patients with hemophilia A in a postmarketing routine clinical practice.

Inhibitor development, safety, and efficacy of Advate® in previously untreated patients with hemophilia A in a postmarketing surveillance in Japan.

Rurioctocog alfa (recombinant Factor VIII: AdvateⓇ) is available for the control of bleeding in patients with hemophilia A in Japan. To evaluate the immunogenicity, safety, and efficacy of prophylactic and on-demand use of rurioctocog alfa, postmarketing surveillance was conducted on 114 previously untreated Japanese patients aged 0-82 years with ≤ 3 exposure days under the conditions of routine clinical practice. A post-hoc comparison of mean annualized bleeding rates between patients in the regular prophylaxis group (7.4 bleeds/year) and in the on-demand treatment group (15.7 bleeds/year) using a negative binomial model found a statistically significant difference (P = 0.0164) in the subset of patients with severe hemophilia A. Favorable prophylactic and on-demand hemostatic efficacy ("excellent" or "good") was shown in 71.4-88.5% across all treatment regimens. A total of 31 events of adverse drug reactions were reported. Of 114 patients, 21 (18.4%) developed de novo FVIII inhibitor; of these, 17 occurred within 50 exposures. One death was reported. A family history of positive inhibitors was significantly associated with inhibitor development (Fisher exact P value = 0.0004); no other risk factors were identified. Rurioctocog alfa was found to be well-tolerated and effective in previously untreated Japanese patients with hemophilia A in this postmarketing surveillance of routine clinical practice.

Correction to: Inhibitor development, safety, and efficacy of Advate® in previously untreated patients with hemophilia A in a postmarketing surveillance in Japan.

The authors would like to correct the errors in the publication of the original article. The correction details are given below.

Perioperative safety and hemostatic efficacy of Advate® in patients with hemophilia A in a postmarketing surveillance in Japan.

Rurioctocog alfa (recombinant factor VIII: Advate®) is available for the control of bleeding among patients with hemophilia A in Japan. To evaluate the perioperative safety and hemostatic efficacy of Advate®, a postmarketing surveillance was conducted in Japanese patients undergoing surgery in a real-world setting. A total of 74 surgical procedures performed in 58 subjects aged 0-75 years, including three females, were studied. A hemostatic efficacy rating of "excellent" or "good" was reported in 73/74 surgical procedures (98.6%). Perioperative bleeding was successfully controlled by Advate® in five subjects with positive FVIII inhibitors (2.4-9.1 BU/mL). Advate® was administered at higher initial bolus doses (114-385 IU/kg) and at higher rates by subsequent initial continuous infusion (8.3-15 IU/kg/hour) in the five subjects with inhibitor than in the subjects without inhibitor (n = 47; mean initial bolus dose: 53.4 IU/kg; subsequent mean initial continuous infusion: 3.8 IU/kg/h). Adverse drug reactions were reported in 7/74 (9.5%) procedures, two of which were the development of de novo FVIII inhibitors. Overall, the perioperative use of Advate® in a real-world setting was found to be safe and effective among Japanese patients with hemophilia A.

Correction to: Efficacy and safety of full-length pegylated recombinant factor VIII with extended half-life in previously treated patients with hemophilia A: comparison of data between the general and Japanese study populations.

The authors would like to correct the error in Table 2 in the original publication of the article. The "Blood type" is not described in any part of "Results" and "Discussion" and had no impact on the conclusion hence the bottom of the table is removed.

Efficacy and safety of full-length pegylated recombinant factor VIII with extended half-life in previously treated patients with hemophilia A: comparison of data between the general and Japanese study populations.

Rurioctocog alfa pegol (BAX 855) is a novel third-generation recombinant factor VIII whose active ingredient is chemically modified with polyethylene glycol. A global multicenter phase 2/3 study of the product in 137 patients (including 11 patients from Japan) with severe hemophilia A aged 12-65 years, reported an extended half-life and a good tolerability profile, as well as a significantly lower annualized bleeding rate in the prophylactic treatment arm than in the on-demand treatment arm. Using descriptive statistics, a post hoc analysis was performed to compare the pharmacokinetics, safety, and efficacy profiles of the product in the Japanese subpopulation and the overall population. Extended half-life was demonstrated in the Japanese subpopulation. The mean [standard deviation (SD)] annualized bleeding rates in the prophylactic treatment arm were 3.7 (4.7) for the overall population (n = 120) and 4.0 (3.4) for the Japanese subpopulation (n = 11). The proportion of bleeds reported as excellent or good was 94.9% (149/157) in the overall population, whereas that in the Japanese subpopulation was 92.3% (12/13). No FVIII inhibition or anaphylactic reaction was reported in the Japanese subpopulation. The post hoc comparisons demonstrated similar pharmacokinetic, safety, and efficacy profiles between the overall population and the Japanese subpopulation.

First case report of hemophilia B Leyden in Japan.

Hemophilia B Leyden is a unique subtype of hemophilia B, characterized by increasing factor IX activity (FIX:C) after puberty and a lower normal range of FIX:C throughout adulthood. However, to date, no Japanese case has been reported. Here, we report a case of hemophilia B Leyden in a 22-year-old male. He suffered from subgaleal hematoma, and was subsequently diagnosed with hemophilia B (FIX:C 0.2%) in the neonatal period. Both his parents are Japanese. There was no history of hemophilia in his family. FIX:C gradually increased with age (8% at age = 1; 14% at age = 7; 19% at age = 12; 32% at age = 18). FIX:C is within the range 30-40% in recent several years. He once required administration of FIX concentrate against traumatic tongue bleeding at 7 years of age. Genotyping analysis of FIX was performed after informed consent at 21 years of age, and a point mutation (c.-35G>A) was detected. This mutation has been reported previously as the Leyden mutation. Although it has been reported that hemophilia B Leyden is seen in 1.9% of patients with hemophilia B, the present case is the first report of hemophilia B Leyden from Japan.