Plasma-derived Clotting Factor Research Articles

Kinetic Modeling for BT200 to Predict the Level of Plasma-Derived Coagulation Factor VIII in Humans.

Lack of Factor VIII (FVIII) concentrates is one of limiting factors for Hemophilia A prophylaxis in resource-limited countries. Rondaptivon pegol (BT200) is a pegylated aptamer and has been shown to elevate the level of von Willebrand Factor (VWF) and FVIII in previous studies. A population pharmacokinetic model for BT200 was built and linked to the kinetic models of VWF and FVIII based on reasonable assumptions. The developed PK/PD model for BT200 described the observed kinetic of BT200, VWF, and FVIII in healthy volunteers and patients with mild-to-moderate hemophilia A from two clinical trials. The developed model was evaluated using an external dataset in patients with severe hemophilia A taking recombinant FVIII products. The developed and evaluated PK/PD model was able to describe and predict concentration-time profiles of BT200, VWF, and FVIII in healthy volunteers and patients with hemophilia A. Concentration-time profiles of FVIII were then predicted following coadministration of plasma-derived FVIII concentrate and BT200 under various dosing scenarios in virtual patients with severe hemophilia A. Plasma-derived products, that contain VWF, are more accessible in low-resource countries as compared to their recombinant counterparts. The predicted time above 1 and 3 IU/dL FVIII in one week was compared between scenarios in the absence and presence of BT200. A combination dose of 6 mg BT200 once weekly plus 10 IU/kg plasma-derived FVIII twice weekly maintained similar coverage to a 30 IU/kg FVIII thrice weekly dose in absence of BT200, representing only 22% of the FVIII dose per week.

Reconstruction of the historic time course of blood-borne virus contamination of clotting factor concentrates, 1974-1992.

Factor VIII and IX clotting factor concentrates manufactured from pooled plasma have been identified as potent sources of virus infection in persons with hemophilia (PWHs) in the 1970s and 1980s. To investigate the range and diversity of viruses over this period, we analysed 24 clotting factor concentrates for several blood-borne viruses. Nucleic acid was extracted from 14 commercially produced clotting factors and 10 from nonremunerated donors, preserved in lyophilized form (expiry dates: 1974-1992). Clotting factors were tested by commercial and in-house quantitative PCRs for blood-borne viruses hepatitis A, B, C and E viruses (HAV, HBV, HCV, HEV), HIV- types 1/2, parvoviruses B19V and PARV4, and human pegiviruses types 1 and 2 (HPgV-1,-2). HCV and HPgV-1 were the most frequently detected viruses (both 14/24 tested) primarily in commercial clotting factors, with frequently extremely high viral loads in the late 1970s-1985 and a diverse range of HCV genotypes. Detection frequencies sharply declined following introduction of virus inactivation. HIV-1, HBV, and HAV were less frequently detected (3/24, 1/24, and 1/24 respectively); none were positive for HEV. Contrastingly, B19V and PARV4 were detected throughout the study period, even after introduction of dry heat treatment, consistent with ongoing documented transmission to PWHs into the early 1990s. While hemophilia treatment is now largely based on recombinant factor VIII/IX in the UK and elsewhere, the comprehensive screen of historical plasma-derived clotting factors reveals extensive exposure of PWHs to blood-borne viruses throughout 1970s-early 1990s, and the epidemiological and manufacturing parameters that influenced clotting factor contamination.

Parvovirus B19 DNA and antibodies in Chinese plasma donors, plasma pools and plasma derivatives.

Human parvovirus B19 (B19V) is a common contaminant found in plasma pools and plasma derivatives. Previous studies were mainly focused on limited aspects, further assessment of prevalence of B19V DNA and antibodies in plasma donors, the contamination of B19V in pooled plasma and plasma derivatives should be performed in China. Individual plasma donors' samples from four provinces and pooled plasma from four Chinese blood product manufacturers were collected and screened using B19V DNA diagnostic kits between October 2018 and May 2020. The positive samples were investigated for the seroprevalence of B19V antibodies and subjected to sequence analysis and alignment for phylogenetic studies. Moreover, 11 plasma donors who were B19V DNA-positive at their first testing were also followed during the later donation period. Additionally, 400 plasma pools and 20 batches of plasma derivatives produced by pooled plasma with a viral load of B19V DNA exceeding 104IU/mL were also collected and tested for B19V DNA and antibodies. To comprehensively and systematically determine the frequency and viral load of B19V DNA in plasma donors, pooled plasma, and plasma derivatives from four Chinese blood product manufacturers. A total of 17,187 plasma donors were analyzed and 44 (0.26%) specimens were found positive for B19V DNA. The quantitative DNA levels ranged from 1.01 × 101 to 5.09 × 1012 IU/mL. Forty-four DNA-positive specimens were also investigated for the seroprevalence of B19V antibodies, 75.0% and 2.3% of which were seropositive for B19V IgG and IgM antibodies, respectively. The phylogenic analyses showed that the prevalent genotypes in the four provinces' plasma donors belonged to B19V Genotype 1. Eleven individual plasma donors who were B19V DNA-positive at the first donation were then followed for a period, and in general, the DNA levels of B19V gradually decreased. Moreover, 64.8% (259/400) of the pooled plasma was contaminated by B19V, with concentrations of 1.05 × 100-3.36 × 109IU/mL. Approximately 72.6% of the DNA-positive plasma pools were only moderately contaminated (<104 IU/mL), while 27.4% contained >104 IU/mL. Twenty batches of plasma derivatives produced by pooled plasma with a viral load of B19V DNA exceeding 104IU/mL were also tested. B19V was detected in 5/5 PCC samples and 5/5 factor VIII samples but was not found in the intravenous immune globulin and albumin samples. The contamination of B19V in pooled plasma and plasma-derived clotting factor concentrates is serious. Whether B19V nucleic acid testing (NAT) screening of plasma and plasma derivatives is launched in China, blood product manufacturers should spontaneously perform B19V NAT screening in plasma donors and mini-pool plasma. These measures can ensure that samples with high titer B19V DNA are discarded in order to prevent and control this transfusion transmitted virus.

144: COMPARISON OF FIXED VERSUS WEIGHT-BASED PROTHROMBIN COMPLEX CONCENTRATE DOSING IN CARDIAC SURGERY

Introduction: Excessive bleeding after cardiac surgery is a major complication associated with increased morbidity and mortality. Intraoperative use of plasma-derived coagulation factors, such as four-factor prothrombin complex concentrate (4F-PCC), have been introduced into clinical practice to attenuate adverse effects attributable to postoperative hemorrhage. Although recent literature reports positive outcomes with the use of lower, fixed doses of 4F-PCC for emergent anticoagulation reversal, there is a paucity of literature evaluating fixed dosing in the cardiac surgery setting. The purpose of this study is to compare the rates of moderate- or higher severity postoperative bleeding associated with use of a fixed-dose versus weight-based 4F-PCC dosing strategy in cardiac surgery patients. Methods: A retrospective cohort study was performed of adult patients who received either weight-based (25 IU/kg) or fixed-dose (1500 IU) 4F-PCC during a cardiac surgical procedure over a 2-year period. Bleeding outcomes were determined by postoperative blood product transfusion requirements, chest tube output volume, and the need for surgical reexploration due to bleeding complications. Results: Of the 122 patients included, 58 received weight-based 4F-PCC whereas 62 were managed with a fixed-dose strategy. Rates of moderate- or higher severity bleeding were similar between weight-based and fixed dosing groups (56.9% vs. 46.8%, respectively; χ2 = 3.8467, p = .278) despite the use of significantly lower total 4F-PCC doses in the fixed-dose 4F-PCC cohort (25.5 U/kg vs. 21.6 U/kg; z = -2.11, p = .04). Postoperative deep vein thrombosis occurred more frequently in the weight-based dosing group as compared to the fixed-dose cohort (8.6% vs. 0%; p = .02). Conclusions: Compared to a weight-based dosing strategy, intraoperative administration of fixed-dose 4F-PCC was associated with similar postsurgical bleeding outcomes and lower rates of deep vein thrombosis in postoperative cardiac surgery patients. Larger, prospective studies are needed to validate these findings and further evaluate the impact of fixed-dose 4F-PCC on patient-centered outcomes in the postoperative cardiac surgery population.

Intravenous Lentiviral Gene Therapy for Hemophilia a: In Vitro and In Vivo Assessment of Universal Versus Tissue-Specific Promoters

Background：Hemophilia A (HA) is an X-linked monogenic coagulation disorder resulting from deficiency of the factor VIII (FVIII, F8) gene in the intrinsic coagulation cascade. The current treatment of HA is based on protein replacement therapy (PRT) through plasma-derived coagulation factors or recombinant proteins with limitations of short half-life, high cost, and life-time requirement of the treatment. Gene therapy has become a promising treatment for HA.Methods and Materials: We developed an advanced lentiviral vector (LV) system for intravenous (iv) F8 gene therapy. A selective codon optimized and B-domain deleted human F8 (hF8BDD) gene was synthesized, sequenced and functionally verified. LVs carrying a universal EF1α promoter, or several modified tissue-specific promoters including endothelial- (VEC), endothelial and epithelial- (KDR), and two megakaryocyte-specific (ITGA and Gp) promoters, were biologically and immunologically characterized in vitro using human endothelial and megakaryocytic cell lines, EA-hy926 and DAMI, and in vivo using F8 knockout (KO) mice.Results: We investigated the different LV promoter constructs and found that LV-VEC-F8BDD exhibited the highest virus packaging (1.3x10 9 transduction units/ml) and transduction efficiencies compared with the other LV constructs. Tissue-specific expression of the VEC, KDR, ITGA and Gp promoters was confirmed in EA-hy926 and DAMI cells by RT-PCR, Western blot and ELISA analyses. We detected F8 activities close to 6 folds and 4.5 folds above the normal plasma level from the EF1a LV-F8BDD transduced EA-hy926 cells and DAMI cells, respectively, whereas the VEC LV in EA-hy926 cells and the ITGA-LV in DAMI cells exhibited F8 activities at 1.5 folds and 5 folds above the normal plasma level, respectively. In vivo studies in F8 KO mice via iv injection of LVs after reduced radiation conditioning illustrated preferential vector expression in different cell lineages, with high expression of EF1a vector in CD11b, F4/80 and Ly-6G positive immune cells, and preferential expression of VEC vector in CD31 positive endothelial cells, and ITGA and Gp vectors in CD41 positive megakaryocytes. In addition, we detected variable phenotypic corrections as well as anti-F8 immune responses in the F8 KO mice treated with the different LVs. The iv deliveries of VEC and Gp F8BDD vectors illustrated therapeutic F8 activities over time, around 25% and 8%, respectively, in 60 days, which increased to high levels (80% and 25%, respectively) after 120 days (Figure A). Kinetic analyses of anti-F8 IgG and inhibitor titers (Bethesda assay) of the treated mice showed that the VEC vector exhibited the lowest F8 inhibitory immune response over time (Figure B).Conclusion: Based on the in vitro and in vivo studies, our results suggest that for HA gene therapy, optimal rather than high F8 expression is critical, and tissue-specific expression but not universal expression can reduce adverse inhibitor effect. We demonstrated that the LV-VEC-F8BDD vector displayed high tissue specificity in vivo, and high transgene delivery efficiency, high coagulation function and low immunogenicity. In addition, iv LV gene therapy could be a safe, convenient and effective HA gene therapy strategy. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

Pharmacist Integration into the Hemophilia Treatment Centre: A Canadian Pilot Project to Optimize Treatment and Improve Cost-Savings Using Pharmacokinetic Assessments of Hemophilia Patients

ContextProphylactic treatment with coagulation factors in patients with hemophilia A and B is associated with significant costs to the health care system. Whether recombinant or plasma-derived therapies, factors are expensive products that follow complicated pharmacokinetic (PK) trajectories and are subject to tremendous inter-individual variation, making their efficient use challenging.Effective management of these products therefore requires tailoring treatment to the patient. To do so, it is essential to systematically assess and interpret the PK profiles of patients. A dedicated pharmacist could greatly assist this process by standardizing the approach and assisting with interpretation. In Canada, pharmacists are not currently part of the comprehensive care team for the hemophilia population.AimThe purpose of this pilot project was to determine whether employment of a pharmacist as part of the Hemophilia Treatment Centre (HTC) would be an effective strategy to reduce costs associated with clotting factor prophylaxis regimens and identify the pharmacist's activities associated with this new role.MethodsThis project occurred at the Children's Hospital of Eastern Ontario (CHEO), Ottawa, Canada, a tertiary pediatric hospital serving 500,000 children and youth. A cost-minimization analysis was conducted to compare the pre-intervention strategy, current model of care without pharmacist involvement, to the post-intervention strategy, model of care that included a pharmacist in the HTC. The analysis was performed from the perspective of the formulary manager, Canadian Blood Services, with a 1-year time horizon.The pharmacist was assigned for the period of 1-year including a 3-month phase-in period during which no interventions were done by the pharmacist, followed by 9 months of specific action on optimization protocols with the goal of achieving cost savings while maintaining best patient care. McMaster's Web-Accessible Population Pharmacokinetic Service (WAPPS-Hemo), which generates PK profiles, served as the basis for therapeutic optimizations. CHEO patients with moderate to severe hemophilia A or B or von Willebrand disease (vWD) receiving prophylactic treatment with recombinant or plasma-derived clotting factor were eligible for a pharmacist assessment.ResultsThe pharmacist performed 18 therapeutic optimizations on 14 patients with moderate to severe hemophilia A or B, and 1 von Willebrand patient, aged 3 to 18 years old. As a result of the pharmacist's intervention (Table 1), clotting factor treatment costs for these patients extrapolated over one year were reduced by 20.5%. This represents a net savings of $225K CAD/year, or $12.5K CAD/optimization/year.The pharmacist not only conducted the PK analyses but also participated in clinics, performed administrative activities, developed practice improvement policies and trained staff (Figure 1). Clinic attendance activities included discussions with families, education on new product administration, and discussions with the multidisciplinary team. Administrative activities consisted of organizing appropriate switch days, coordinating laboratory tests and timing of PK assessments, ensuring entire supply consumption, adverse event reporting and inventory management support.Additionally, a sub-analysis showed that the pharmacist's interventions did not worsen annual bleed rates (ABR). In most cases, the ABRs were improved after their therapy was optimized using pharmacokinetics.ConclusionSubstitution of clotting factor products and reduction of doses undertaken by the pharmacist resulted in significant savings. To date, no increase in bleeding frequencies have been observed in patients with optimized therapy, suggesting that patient outcomes are maintained. Thus, our project demonstrated that the addition of a pharmacist to the HTC to manage recombinant and plasma-derived coagulation factors can optimise the treatment plan and significantly reduce the costs of managing patients with hemophilia.Following the success of this pilot project, Canadian Blood Services will provide additional funding to extend the project and expand its scope to include adult hemophilia patients. If the findings in this project continue to be demonstrated, this will be used as a case study to expand to all HTC across Canada. [Display omitted] DisclosuresKlaassen: Agios Pharmaceuticals: Consultancy; Amgen: Membership on an entity's Board of Directors or advisory committees; Hoffman-La Roche: Consultancy; Novo Nordisk: Consultancy; Octapharma AG: Consultancy; Sanofi: Consultancy; Takeda: Consultancy.

Hemophilia Natural History Study (ATHN 7): Safety of Current Therapies for People with Hemophilia A or B

INTRODUCTION: The recent introduction of new therapies for people with hemophilia A and B (HA and HB) mandates careful monitoring of the safety of these treatments. The primary aim of ATHN 7: A Natural History Study of the Safety, Effectiveness, and Practice of Treatment for People with Hemophilia (NCT03619863) is to monitor the safety of current hemophilia therapies.METHODS: ATHN 7 is a longitudinal, prospective cohort study being conducted at 26 American Thrombosis and Hemostasis Network (ATHN)-affiliated sites. The study is approved by central and local institutional review boards. Any person with a diagnosis of congenital hemophilia A or B (factor VIII or IX activity < 50%) who receives care at a participating site is eligible for inclusion. Participants and/or a parent/guardian sign informed consent and assent prior to participation. Adverse events, including those events designated by the European Haemophilia Safety Surveillance group as well as other adverse events of special interest, are recorded and monitored. Demographic and clinical information are collected at baseline and at least quarterly through participant interview and medical record review. Descriptive statistics of medical history and demographic data as well as longitudinal data are used to characterize the study population.RESULTS: As of June 2021, a total of 391 participants had enrolled in ATHN 7. The median age of participants was 22.5 ± 17.8 years. Males represented 97.7% (382/391) of participants. Eighty-five percent (333/391) were not Hispanic. White participants comprised 82.6% (323/391) of the study population, while 7.9% (31/391) were Black/African American, 3.8% (15/391) were Asian, 1.8% (7/391) were of mixed race, and 3.8% (15/391) were of other or unknown race. The primary diagnosis of participants included 70.1% (274/391) with severe HA, 15.3% (60/391) with moderate HA, 7.2% (28/391) with mild HA, 4.1% (16/391) with severe HB, 2.0% (8/391) with moderate HB, and 1.0% (4/391) with mild HB. Nineteen percent (71/391) of participants had a documented history of an inhibitor at the time of enrollment with a mean peak inhibitor titer of 96.7 ± 214.3 Bethesda Units. Substitution therapy with a non-factor molecule was the primary medication for 43.4% (162/391) participants, while 4.3% (16/391) utilized a plasma-derived clotting factor concentrate, 28.4% (196/391) utilized a standard half-life, recombinant factor concentrate, 18.3% (126/391) utilized an extended half-life recombinant factor concentrate, 4.1% (28/391) utilized a bypassing agent, and 19.3% (133/391) utilized some other hemostatic agent. Continuous prophylaxis was the primary regimen for 79.1% (295/391) participants. The remaining 19.6% (73/391) of participants were on episodic therapy. Within the cohort of 391 participants, a total of 14 adverse events have been reported in 8 participants. No adverse events of special interest were reported. Redness or rash at injection site accounted for 64.2% (9/14) of the reported adverse events, all in participants receiving emicizumab. Two participants experienced bruising or bleeding while on emicizumab. Two participants on emicizumab were diagnosed with malignancy, neither found to be attributed to their therapy. One participant developed an allergic reaction to their standard half-life recombinant factor concentrate.DISCUSSION: Open to enrollment in January 2019, ATHN 7 has now collected 18 months of longitudinal safety data for therapies used to treat HA and HB in 391 participants, an addition of 12 months and 24 participants since our last report. As the study was designed to enhance representation of those utilizing substitution therapy, almost half of the participants were on emicizumab for prophylaxis of bleeding. Adverse events attributable to hemophilia therapy was limited to minor skin reactions. As previously reported, a single participant experienced delayed bleeding after closed head trauma (despite factor replacement and normal intracranial imaging at the time of the event), providing potentially important information on the risk of delayed bleeding from significant trauma in those receiving emicizumab. Over the coming year, participants in ATHN 7 will be transitioned to ATHN's new longitudinal natural history study, ATHN TRANSCENDS (NCT04398628). DisclosuresBuckner: Pfizer: Honoraria; Takeda: Honoraria; Bayer: Honoraria; Sanofi: Honoraria; Spark: Honoraria; Genetech: Honoraria; CSL Behring: Honoraria; Novo Nordisk: Honoraria; Tremeau Pharmaceuticals: Consultancy, Honoraria; BioMarin: Consultancy, Honoraria; uniQure: Consultancy, Honoraria; American Thrombosis: Membership on an entity's Board of Directors or advisory committees; Hemostasis Network: Membership on an entity's Board of Directors or advisory committees. Carpenter: Hemophilia and Thrombosis Research Society: Membership on an entity's Board of Directors or advisory committees; Kedrion Pharmaceuticals: Honoraria; Genentech: Honoraria; Novo Nordisk: Honoraria. Raffini: Genentech: Consultancy; CSL Behring: Consultancy; HEMA Biologics: Consultancy; XaTek: Consultancy; Bayer: Consultancy. Zia: Takeda: Consultancy; Hemophilia and Thrombosis Research Society: Membership on an entity's Board of Directors or advisory committees. Recht: Hema Biologics: Consultancy; Kedrion: Consultancy; Novo Nordisk: Consultancy; Octapharma: Consultancy; Pfizer: Consultancy; Sanofi: Consultancy; Takeda: Consultancy; uniQure: Consultancy; Foundation for Women and Girls with Blood Disorders, Partners in Bleeding Disorders: Speakers Bureau; American Thrombosis and Hemostasis Network: Current Employment; Oregon Health & Science University: Current Employment; Genentech: Consultancy; CSL Behring: Consultancy; Catalyst Biosciences: Consultancy.

Parvovirus 4 in Individuals with Severe Hemophilia A and Matched Control Group

Background: Hemophilia is a well-known bleeding disorder with worldwide distribution. Replacement therapy, using plasma-derived or recombinant coagulation factors, comprises a gold standard regimen for the treatment. Regardless of the advancements made in viral inactivation methods in the production of plasma-derived coagulation factors, the possibility of transmission of new viral infections remained as a noticeable concern yet. The aim of the current study was to investigate the status of parvovirus 4 (PARV4) in severe hemophilia A, von Willebrand disease (vWD), and healthy control. Materials and Methods: In the current case-control study, 76 patients with hemophilia and vWD and 60 individuals from their family members entered the study. Nested PCR used to determine the presence of PARV4 in study subjects (76 cases). To characterize the PARV4 genotype, positive samples subjected to sequencing and phylogenetic analysis. Results: PARV4 genome detected in 11 (14.47%) patients with bleeding disorders. Among whom, nine patients (14.75%) were with severe hemophilia A and two (13.33%) patients with vWD. Only five healthy controls (8.33%) were positive for PARV4. All PARV4 sequences were found to be genotype 1. Conclusion: PARV4 infection in patients with hemophilia and vWD was higher than the control group. While detection of PARV4 DNA in patients with bleeding disorders may not necessarily reflect a clinical urgency, future investigations are needed to define the clinical significance of PARV4. It seems the detection of the virus immune signature of PARV4 infection, particularly in the context of acute and persistent infections, needs to focus on cellular and tissue targets.

Evaluation of Plasma-Derived FVII Efficacy for the Treatment of Bleeding in a Murine Model of Hemophilia a

BackgroundRecombinant human activated factor VII (rhFVIIa) has been used successfully to treat hemophilic patients with neutralizing antibodies to FVIII or FIX. High doses of FVIIa are known to be effective in opposing bleeding in hemophilia B mice and in a mouse model of antibody-induced hemophilia A. The therapeutic indications for human plasma-derived coagulation factor VII (pdFVII) include the prophylaxis and treatment of bleeding disorders in isolated congenital or acquired factor VII deficiency. These preparations are considered to be ineffective in hemophilia A in the presence of inhibitors as they do not contain activated factor VII and therefore cannot be used in haemophiliac patients with inhibitors.AimHere, we investigated the potential use of pdFVII to induce hemostasis in a mouse model of congenital hemophilia A with high-titer inhibitors and antibody-induced hemophilia A in wild-type mice.MethodsF8 KO mice were given 2 IU recombinant human FVIII intravenously weekly for 4 weeks. All mice that developed high-titer inhibitors (>5 BU/ml) were selected to be used in tail transection experiments. Additionally, a model of antibody-induced hemophilia was used by injecting C57BL/6 wild-type mice with 2 doses of murine plasma containing high-titer inhibitors. Mice were anesthetized and tails transected at a cross-sectional diameter of 1.5 mm; the tail was immediately placed in thermostated saline, and the duration of active bleeding was recorded. Bleeding was monitored for 10 minutes. Blood loss was determined by measuring the amount of released haemoglobin in the saline. Mice were pre-treated 15 minutes before haemostatic challenge with a single i.v. injection of saline, rhFVIIa (4 mg/kg) or pdFVII (500 IU/kg).ResultsAdministration of both rhFVIIa and pdFVII corrected the bleeding tendency in both animal models. In particular, pdFVII and rFVIIa treatments caused a marked reduction in the mean bleeding index score of hemophilia A mice with inhibitors in comparison to mice treated with vehicle only (vehicle, mean=5750, s.e.m.= 438; pdFVII, mean=1301, s.e.m.= 819; rFVIIa, mean=1101, s.e.m.=565; P < 0.001 for pdFVII vs vechicle and rFVIIa vs vehicle comparisons, NS for rFVIIa vs pdFVII; ANOVA followed by Bonferroni's multiple comparison test). Comparable results were obtained in the antibody-induced hemophilia model. No statistically significant differences were observed between groups treated with rFVIIa or pdFVII in both models.ConclusionsOur results provide evidence that pharmacological doses of both rFVIIa and pdFVII are effective in promoting hemostasis in animal models of congenital hemophilia A with inhibitors and antibody-induced hemophilia A in wild-type mice. DisclosuresNo relevant conflicts of interest to declare.

The Global Need and Availability of Plasma Coagulation Factors VIII and IX in Hemophilia Context: A Global Health Estimate Reporting

Background: Blood components supplying is essential for health systems worldwild. However, the availability, need and unmet need of plasma derived coagulation factors, fully intended for hemophilia treatment, are often unknown. Methods: We aimed to estimate availability, need and unmet need of plasma derived coagulation factors VIII and IX in national, regional and global level. Data from 2018 Report on the Annual Global Survey by The World Federation of Hemophilia was used to get plasmatic factors usage (considered equivalent to availability) of countries covering 87% to 88% of global scope. We used the 2017 European consensus for treatment of hemophilia on minimum consumption of factors VIII and IX 4 UI and 0·5UI per capita, considered equivalent to factor need. The unmet need was the difference between need and availability. Findings: Among the 111 countries reporting factor VIII use, remained a 84 country sample with 95% confidence interval and among 105 countries reporting factor IX use, remained a 77 country sample and same confidence interval. The availability was above need in four countries for factor VIII and in 11 countries for factor IX. Interpretation: Although not always was possible to identify trends related to socioeconomic aspect, great part of the sub-Saharan Africa and south Asia countries had elevated unmet needs for both plasmatic factors. In order to overcome the scarce information on this set, this study can potentially contribute to better organized and better planned health systems to benefit both individuals and whole populations. Funding: None Declaration of Interests: All other authors declare no competing interests. Ethics Approval Statement: The present study did not require approval by an institutional review board.

Perioperative management of a pediatric patient with suspected type 1 von Willebrand disease undergoing tonsillectomy: a case report

BackgroundVon Willebrand disease (VWD) is the most common inherited bleeding disorder in humans. Coagulopathies such as VWD are evidently risk factors for post-surgical bleeding. Perioperative management of patients with VWD remains controversial and is a major clinical concern.Case presentationA 5-year-old girl was scheduled for tonsillectomy under general anesthesia. Preoperative laboratory tests revealed prolongation of activated partial thromboplastin time and a mild decrease in von Willebrand factor (VWF) activity. Prophylactic administration of desmopressin or VWF was not performed. During tonsillectomy, oozing from the surgical wound was uncontrollable by conventional hemostasis techniques, but complete hemostasis was ensured by plasma-derived coagulation factor VIII concentrate containing VWF.ConclusionPediatric patients with mild abnormalities in preoperative laboratory tests may have coagulopathies. Prophylactic intervention and/or the preparation of a sufficient amount of coagulation factor VIII concentrate containing VWF may be required in patients suspected of having VWD or with mild VWF deficiency.

Prevalence and risk factors associated with hepatitis C among Brazilian male patients with haemophilia: A long-term follow-up.

People with haemophilia represent a population with a high prevalence of HCV infection due to the use of blood components and plasma-derived clotting factor concentrates before the introduction of viral-inactivating procedures (in the 1980s) and screening for HCV (in the 1990s). About 80% of HCV-infected patients have chronic HCV infection, and at least 20% develop end-stage liver disease. The aim of the study was to assess current anti-HCV positivity in a large cohort of Brazilian haemophilia patients and to determine associated factors with HCV exposure. The study retrospectively analysed medical records of all male haemophilia patients attended the main public referral blood centre in Belo Horizonte, Brazil, from January 1985 to January 2015. Sociodemographic, epidemiological and serological characteristics were collected of all participants tested for anti-HCV. Among 724 patients enrolled in the study, anti-HCV was positive in 259 resulting in a seroprevalence of 35.8% (95% CI: 32.3%-39.3%). Factors independently associated with previous exposure to HCV were as follows: age older than 30years, moderate to severe haemophilia, detection of inhibitor at least once in lifetime and previous exposure to hepatitis B virus (HBV) infection or HIV infection. Otherwise, exclusive previous use of inactivated clotting factors resulted in a significant decrease in the chance of positivity for anti-HCV. At the end of cohort period, patients with positive anti-HCV had a 3-fold higher risk of death. This study showed that hepatitis C infection remains a critical problem for Brazilian haemophilia patients and reinforced the need to unify efforts to eradicate it.

Administration of plasma-derived coagulation factor VIII during the perioperative period of mastectomy for breast cancer with acquired von Willebrand syndrome

BackgroundAcquired von Willebrand syndrome (aVWS) is a rare bleeding disorder with laboratory findings similar to those of congenital von Willebrand disease (VWD). Patients with aVWS may require prophylactic treatment to prevent excessive bleeding following surgery. To our knowledge, to date, there have been no reports on perioperative management for breast cancer patients with aVWS.Case presentationA 60-year-old woman with breast cancer was diagnosed with aVWS due to polycythemia vera. Pre-operative laboratory testing showed a high platelet count and low von Willebrand factor (VWF) activity. The VWF activity did not improve despite an attempt to suppress platelet count with hydroxyurea. Therefore, we decided to perioperatively supplement with plasma-derived factor VIII (FVIII) containing von Willebrand factor (FVIII/VWF concentrates) to perform curative surgery for breast cancer safely. Consequently, the patient did not develop hemorrhage during/after surgery and was discharged on postoperative day 7, as planned, without problems.ConclusionsFor a patient with aVWS, which carries a high risk of hemorrhage during the perioperative period, initiation of appropriate management like supplementation of FVIII/VWF concentrates might enable safe curative surgery for breast cancer, and collaboration with the hematology department is critical.

Recent market status and trends of fractionated plasma products

The global plasmas proteins market has continued to grow throughout the past decade, reaching over $21 billion in sales in 2016. Five trends have recently affected the sales of plasma proteins significantly, including: (I) immunoglobulin has increased its primacy as the plasma market driver; (II) rise of China’s plasma industry, both domestically and globally; (III) emergence and growth of several specialty products, including C1 esterase inhibitor (C1-INH), prothrombin complex concentrate (PCC) and alpha-1 antitrypsin (AAT); (IV) relative decline of the plasma-derived coagulation factors in favor of recombinant alternatives; and (V) growing role of the United States as the global supplier of source plasma. Due to these events, the industry has positively affected more patients as treatment has expanded in many areas around the globe.

Purification of Plasma-Derived Coagulation Factor VIII by Immobilized-Zn2+ and -Co2+ Affinity Chromatography

Coagulation factor VIII (FVIII) is a glycoprotein that plays a crucial role in the clotting cascade. Replacement therapies with recombinant and plasma-derived concentrates of FVIII are used for treatment of hemophilia A. We have previously purified the human plasma FVIII by immobilized metal affinity chromatography (IMAC) using Cu2+ as the metal ligand. In this work we report the purification of FVIII using Zn2+ and Co2+, two metal ions that bind proteins more weakly. Human plasma was directly applied to the anion-exchange ANX Sepharose FF column and the eluate was used as starting material for the studies in IMAC columns. Using imidazole as desorbing agent, FVIII was recovered with 65% activity in the IMAC-Zn2+ column and with 74% activity in the IMAC-Co2+ column. Purification factors were 4 and 9, respectively. Using a pH gradient, FVIII was eluted at pH 5.0 with 17% activity in the IMAC-Zn2+ and 77% activity in the IMAC-Co2+. Vitamin K-dependent proteins, a family of proteins that includes Prothrombin and coagulation factor IX, coeluted with FVIII in the ANX Sepharose FF column and were recovered with the unbound proteins on both IMAC columns. Therefore, Co2+ and Zn2+ columns were as effective as the Cu2+ column in separating FVIII from vitamin K-dependent proteins. Finally, we have shown that FVIII remained complexed with the von Willebrand factor.

Development of aptameric affinity ligands specific to human plasma coagulation factor VIII using SEC-SELEX

Protein specific aptamers are highly applicable affinity ligands in different fields of research and clinical applications. They have been developed against various targets, in particular, bio-macromolecules such as proteins. Among human proteins, the coagulation factors are the most attractive targets for aptamer selection and their specific aptamers had valuable characteristics in therapeutic and analytical applications. In this study, a plasma derived coagulation factor VIII was considered as the protein target for DNA aptamer selection using size exclusion chromatography-SELEX. Potential aptameric oligonucleotides with high affinity and specificity were achieved during eight rounds of selection. Binding affinity constant of selected aptamer and aptameric enriched pool were in nanomolar range that was comparable to monoclonal antibodies. Further improvement studies can result in aptamers that are more promising as an industrial affinity ligand for the purification of anti-hemophilia factor from plasma source.

Identification of Four Novel Factor VIII Gene Mutations and Protein Structure Analysis using Molecular Dynamic Simulation

Hemophilia A is an X-linked recessive hemorrhagic disorder caused by mutations in the factor VIII gene. To find out known and novel causative mutations in Hemophilia A, we carried out genetic analysis among Saudi patients. Twenty six Patients who were negative for inv-1/inv-22 were selected for analysis with Multiplex Ligation-dependent Probe Amplification (MLPA) and Sanger sequencing. Furthermore the functional and structural effects of the novel mutations were predicted using Molecular dynamic simulation. The results showed three known large deletions in 6 samples (delE8,9,10,11,12,13,14; delE7,8,9,10; and delE4) and twelve mutations in 18 samples; four of them were novel. The novel mutations detected were two substitutions in exon 8 at position c.1021G>C, p.(Ala341Pro) and position c.1183A>C, p.(Lys395Gln), one substitution in exon13 at position c.1930T>A, p.(Leu644Met), and one substitution in exon22 at position c.6322G>C, p.(Ala2108Pro). Clinical data of Patients with novel mutations showed <1% Factor VIII levels (severe hemophilia) with episodic bleeding and were on a routine treatment of plasma derived clotting factor concentrate. This data is in line with MD simulation showed significant changes of the different mutations on the protein structure compared to native protein. These results should enrich the spectrum of mutations and enlarge the factor VIII protein’s database in Saudi Arabian population; furthermore it showed that the in silico MD simulation for functional and structural studies could be a reasonable approach for investigating the advance genotype-phenotype correlation.

Updates to the Canadian Immunization Guide: April 2015 to October 2016.

The Canadian Immunization Guide (CIG) is a trusted, reader-friendly summary of information and advice on immunization that has been used by health care providers and policy makers for decades. It is continuously updated based on new recommendations from the National Advisory Committee on Immunization (NACI) and the Committee to Advise on Tropical Medicine and Travel (CATMAT), two external advisory bodies to the Public Health Agency of Canada. In September 2016, the CIG moved to a new web platform that has improved navigability and is more mobile friendly. Between April 2015 and October 2016, five new NACI statements were published and are reflected in the CIG. The objective of this article is to provide readers with highlights of recent key changes to active vaccine recommendations in the CIG. For example, for Hepatitis (HA) vaccine, it may now be administered to persons six months of age and older and considered for all individuals receiving repeated replacement of plasma-derived clotting factors. There are now new recommendations for the use of HA immunoglobulin post-exposure prophylaxis. For Human papillomavirus (HPV) vaccine, any of the authorized HPV vaccines in Canada, including HPV9 vaccine, can be used according to the recommended HPV immunization schedules. For influenza vaccine, adults with neurologic or neurodevelopment conditions have been added to the group for whom influenza vaccination is particularly recommended, high-dose influenza vaccine has been approved for use in Canada in adults ≥65 years of age and live attenuated influenza vaccine (LAIV) is no longer a preferentially recommended product for use in children and adolescents. On an individual basis, pneumococcal conjugate 13-valent (PNEU-C-13) vaccine may be recommended to immunocompetent adults aged 65 years and older if not previously immunized against pneumococcal disease. When it is given, it should precede the pneumococcal polysaccharide 23-valent (PNEU-P-23) vaccine. Varicella immune globulin may now be administered up to 10 days since last exposure for the purpose of disease attenuation and there were a number of minor changes to the criteria for assessing varicella immunity.

Willingness to pay for eliminating the risk of being infected by blood-borne diseases in regular replacement treatment for patients with haemophilia

Hemophilia is a set of lifelong bleeding disorders linked to the X chromosome. Standard treatment for patients with severe hemophilia is intensive replacement therapy with intravenous injection of coagulation factor concentrates to prevent spontaneous recurrent joint bleed. In the 1980s, many hemophilia patients were infected with HIV and/or hepatitis C transmitted by plasma derived coagulation factor concentrates. In the future, new pathogens could appear and a risk remains that the current manufacturing methods will not be able to eliminate those. The aim of the study is to estimate the value of eliminating the risk of being infected by blood-borne diseases in the treatment of hemophilia which could provide decision-makers with information on how much resource to spend on this purpose to be in line with societal preferences. Individual preferences for safety were elicited from a sample of 821 individuals from the Swedish general population using a web-based questionnaire. The preferences were estimated using the “chained approach” which combines the contingent valuation (CV) and standard gamble (SG) methods. The respondents were asked (1) to state their willingness-to-pay to avoid a temporary, non-fatal injury presented in a health state derived from the EQ-5D instrument, and (2) to choose between living with this injury with certainty or receive a treatment that could restore the respondent to full health immediately, but which entails a risk of being infected by a fatal, blood-borne disease. A value of a statistical life (VSL) in the context of blood-borne diseases of SEK47 million was calculated by “chaining” the answers to the CV question and SG question, and from the VSL we derived a value of a QALY in the context of blood-borne diseases of SEK2.8 million. Using the current mean annual dose of factor concentrate of 268,000 international units (IU) per patient in Sweden, the value of eliminating the risk of being infected by blood-borne diseases would be SEK1.80 per IU corresponding to a price premium of around 45 %.Published: Online April 2016. In print August 2016.

A multi-center clinical observation on safety and efficacy of a plasma derived coagulator factor Ⅷ for treatment of patients with hemophilia A

To evaluate the efficacy and safety of homemade plasma derived coagulation factor Ⅷ in patients with hemophilia A. Patients with congenital hemophilia A who met the inclusive and exclusive criteria were enrolled in the study after informed consent. The doses of factor Ⅷ were calculated according to the weight, disease severity etc. FⅧ activity and infusion efficacy value at 10 min and 60 min after infusion were recorded, as well as adverse events and validity rating according to the improvement of clinical syndromes. Viral infections including HBV, HCV, HIV and FⅧ inhibitor were determined after 3 and 6 months. A total of 65 patients were enrolled in this study, all of whom were evaluable for drug safety. Treatment efficacy was evaluated in 60 patients and 57 cases completed the trial finally. In this 57 cases, most (52/57) subjects were of middle and severe hemophilia A mainly characterized by joint bleeding. Overall response rate of acute bleeding events was classified as "excellent" (70.00%) or "better" (30.00%). The non-responder was 0. FⅧ activity and infusion efficiency value of first administration after 10 min and 60 min improved significantly [10 min: (123.66±47.54)%; 60 min: (108.05±43.24)%]. The incidence of adverse events was 1.54%. Neither allergic reaction nor reactivation of HBV, HCV, HIV was detected after treatment of 3 and 6 months. No FⅧ inhibitor negative patients converted to positive during follow-up. This homemade plasma derived coagulation factor Ⅷ is safe and effective for the treatment of acute bleeding in patients with hemophilia A.