In-vivo Recovery Research Articles

Pharmacokinetic Study of Coagulation Factor Ⅷ in Adults with Severe Hemophilia A

To detect the pharmacokinetic (PK) parameters of coagulation factor Ⅷ (FⅧ) in adult patients with severe hemophilia A, identify the potential factors influencing FⅧ PK, and optimize the use of FⅧ in individual prophylaxis regimens. PK characteristics of FⅧ were studied in a total of 23 severe hemophilia A adults. The correlation of patients' characteristics including age, von Willebrand factor antigen (vWF:Ag), blood group, weight, body mass index (BMI) and FⅧ genotype, with FⅧ PK were evaluated. Individual prophylaxis regimens were given based on FⅧ PK parameters. The mean terminal half‑life (t1/2) of FⅧ was 20.6±9.3 h, ranged from 11.47 h to 30.12 h. The age (r =0.580) and vWF:Ag (r =0.814) were significantly positively correlated with t1/2 of FⅧ. The mean area under the plasma concentration curve (AUC) of FⅧ was 913±399 (328-1 878) IU·h/dl, and the AUC of FⅧ was positively correlated with age (r =0.557) and vWF:Ag (r =0.784). The mean residence time (MRT) of FⅧ was 24.7±12.4 (13.2-62.2) h, and the MRT of FⅧ was positively correlated with age (r =0.664) and vWF:Ag (r =0.868). The mean in vivo recovery (IVR) of FⅧ was 2.59±0.888 (1.5-4.29) IU/dl per IU/kg, the mean clearance (CL) of FⅧ was 3±1.58（0.97-7.18）ml/(kg·h)，and there was no significant correlation of IVR and CL with age and vWF:Ag. According to the individual PK parameters, ultra low-dose, low-dose and moderate-dose FⅧ were applied to 15, 6, 2 adults patients with severe hemophilia A for prophylaxis, respectively. There are significant individual differences in the FⅧ half-life of adult patients with severe hemophilia A. The older the patient, the higher the vWF:Ag level, and the longer the FⅧ half-life. Individual administration is required based on the FⅧ PK parameters to optimize prophylaxis treatment.

Analysis of fibrinogen concentrate pharmacokinetics and dosing for bleeds and surgery in adults, adolescents, and children with congenital afibrinogenaemia and hypofibrinogenaemia.

Congenital afibrinogenaemia and hypofibrinogenaemia are rare coagulation disorders where clotting is impaired due to a lack of fibrinogen. Consequent bleeding episodes (BEs) are treated using human fibrinogen concentrate (HFC). This post-hoc analysis compared HFC pharmacokinetics (PK) and dosing between patient age groups and defined the in vivo recovery (IVR) for children with a- and hypofibrinogenaemia. The analysis used data from the FORMA-01 (Phase 2), FORMA-02 and FORMA-04 (Phase 3) multinational, prospective, open-label studies in patients with a- and hypofibrinogenaemia. HFC PK in adults/adolescents (≥12 years; FORMA-01) and children (<12 years; FORMA-04) was examined. Haemostatic efficacy in BE treatment and perioperative prophylaxis was examined in FORMA-02 and FORMA-04 using an objective 4-point scale, with success defined as excellent/good. Median (range) age was 23 years for FORMA-01 (12-53; n=22), 26.5 years for FORMA-02 (12-54; n=25), and 6 years for FORMA-04 (1-10; n=13). Mean PK parameters were lower for children (AUC, Cmax , IVR; p=.02), while clearance was higher. Median (range) total dose of HFC for all BEs was 59.41mg/kg (32.12-273.80) in adults/adolescents and was 24% higher (ns) in children at 73.91mg/kg (47.45-262.50). Treatment was successful in 98.9% of the 89 BEs in adults/adolescents and in 100% of the 10 BEs in children, with comparable results for perioperative prophylaxis. As expected, HFC PK differed between adults/adolescents and children. However, with the higher doses given to children, HFC showed similar efficacy across age groups. Dose adaptation based on age groups appears recommendable.

Hidden blood loss of total knee arthroplasty in hemophilia arthritis: an analysis of influencing factors

BackgroundTotal knee arthroplasty is the leading way to treat hemophilia arthritis. At present, there is a lack of research on the influencing factors of blood loss in total knee arthroplasty for hemophilia arthritis. This study comprehensively explores the definite factors affecting the hidden blood loss in total knee arthroplasty for hemophilia patients.Materials and methodsNinety-two hemophilia A patients who underwent total knee arthroplasty in our center were included. Demographics, laboratory data, surgical data, and complications were collected. The Gross equation and Sehat equation were used to calculate the estimated value of hidden blood loss. Multivariate linear regression analysis was used to determine the influencing factors of hidden blood loss.ResultThe hidden blood loss of hemophilia A patients undergoing total knee arthroplasty was 1069.51 ± 341.99 mL, and the age was positively correlated with the hidden blood loss (P < 0.001), while tranexamic acid, FVIII prophylaxis, and incremental invivo recovery were negatively correlated with the hidden blood loss (P < 0.001, P = 0.008, P = 0.017).ConclusionElderly patients have a greater risk of blood loss, and additional preventive measures can be appropriately added. Intraoperative intra-articular injection of tranexamic acid is recommended to reduce hidden blood loss, FVIII prophylaxis is recommended for every patient. We recommend that all HA patients measure the incremental invivo recovery and develop a personalized infusion regimen of coagulation factor.

Pharmacokinetics-Guided Perioperative Replacement Therapy in Hemophilia a Patients

▪Purpose: Pharmacokinetics(PK)-based prophylactic treatment has been proven to meet the pharmacoeconomics needs of patients with hemophilia to the greatest extent in recent years，but the way and significance of PK-guided perioperative replacement therapy remain unclear.Methods:In this study, PK parameters (calculated by DAS software), including half-life and in vivo recovery(IVR), were used to guide individualized replacement therapy for surgical patients with hemophilia A. PK profiles were described by a two-compartment model. The collection of perioperative factor VIII(FVIII) plasma concentrations, factor consumption, and blood loss data was used to verify the efficacy of individualized programs.Results:A total of 46 patients underwent 50 surgeries (median age: 32 years, median weight: 60.5 kg), all of which were major surgeries. The median half-life was 15.44h, and the median IVR was 2.29IU dl -1/IU kg -1. In total, 50 surgeries contributed with 528 plasma FVIII activity observations, of which 310 (58.71%) entered the target range. The median intraoperative blood loss of 43 surgeries was 446.9ml. No severe complications occurred during the perioperative period. Hematomas appeared after six surgeries, which have been resolved after treatment at discharge. Inhibitor developed in one patient and was transient. The median consumption of FⅧ concentrates during the perioperative period was 511.7U/kg, which reduced by 26.69% compared with the dosage based on weight (648.3U/kg, P＜0.001). During the perioperative period, the actual factor consumption was consistent with the PK-guided plan (P>0.05). In addition, a negative correlation was found between intraoperative blood loss and immediate postoperative FVIII activity (r= -0.477, P=0.001).Conclusion: PK-guided perioperative replacement therapy in hemophilia A patients can safely and effectively reduce the consumption of FⅧ concentrates. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

Pharmacokinetics of Factor VIII Level in Patients Hemophilia A in Relation to Clinical and Radiological Outcomes

Abstract Background The benefit of pharmacokinetics (PK) -guided dosing is that both prophylactic and “on demand” dosing will be based on actual FVIII trough and peak levels instead of current FVIII estimates based on body weight and in-vivo recovery based dosing. Knowledge will increase with regards the relationship between FVIII level and bleeding in individual patients. The dose and frequency of factor VIII for patients on prophylaxis should only be reduced if clinically justified and impact should be monitored with regard to bleeding events, bleeding pattern and joint status. Objective To assess the trough and peak level of factor VIII in patients with hemophilia A on low dose prophylaxis and its impact on the clinical and radiological joint status. Patients and Methods A cross sectional study was performed in Ain-Shams University, Pediatrics Hospital, Hemophilia Clinic. It included 25 children and adolescents with hemophilia A on prophylactic factor VIII during the period from September 2018 to August 2019. Factor VIII used was recombinant 3rd generation with a dose of 45 IU/Kg/week rounded to the nearest 500IU. Trough level of factor VIII was done before prophylactic dose and peak level was done one hour postinfusion through chromogenic assay using STAGO-Immuno-Def VIII reagent. Clinical joint score and Functional Independence Score of Hemophilia (FISH) were done. Radiological joint scores were done using conventional x-ray, ultrasound and MRI. Cut-off level of trough levels was studied at 1% and 1%-5% of factor VIII. Results Patients were classified into 3 groups,4 patients (21.1%) had trough level &amp;lt;1%, 13 patients (68.4%) had trough level between 1%-5%, 2 patients (10.5%) had trough level &amp;gt; 5%. No significant difference between trough level of factor VIII and clinical joint scores and FISH scores of patients. Median score of the worst joint of patients with trough level &amp;gt;5% was 5 in comparison to 8 and 7 in patients with trough level 1%-5% and &amp;lt;1% respectively. Mean FISH of patients with trough level &amp;gt;5% was 9.50 ± 2.12 in comparison to 12.92 ± 5.41 and 11.00 ± 3.56 for patients with troughs 1%-5% and &amp;lt;1% that was respectively. Comparison between groups with different trough level of factor VIII according to X-ray scores of patients showed no significant difference Conclusion Low trough levels alone did not warrant intensification of the prophylaxis regimen; rather, the dose and dosing frequency should be adjusted based on individual’s bleeding pattern and many other factors as shown in our study the insignificant relation between trough levels of factor VIII and clinical and radiological outcomes.. More frequent factor VIII monitoring and incorporation into population based PK are warranted.

Analysis of gene mutation spectrum and pharmacokinetics of fibrinogen infusion in 146 cases of congenital fibrinogen disorders

目的探讨先天性纤维蛋白原病的基因突变类型与分型、临床表现、实验室检查、诊断及纤维蛋白原替代治疗情况。方法对2003年4月至2020年11月就诊于中国医学科学院血液病医院的146例先天性纤维蛋白原病患者进行回顾性分析。结果146例患者中，男61例（41.8％），女85例（58.2％），就诊时中位年龄为33.5岁；共采集到98例患者的临床症状学信息，34例（34.7％）因出血症状而就诊，33例（33.7％）因手术前检查而确诊，55例（56.1％）患者至少有1次出血，42例（42.9％）无出血表现。纤维蛋白原活性（FIB∶C）与ISTH-BAT出血评分之间呈负相关（rs＝−0.412，P<0.001）。在56例患者中检出34种基因突变（包括新突变16种），其中84.1％为错义突变，FGA外显子2和FGG外显子8突变占全部突变位点的71.4％。无纤维蛋白原血症患者（7例）中位年龄为2（1～12）岁，ISTH-BAT评分为4分；异常纤维蛋白原血症患者（50例）中位凝血酶时间为28.5（19.2～36.6）s。输注纤维蛋白原后1 h、24 h的活性回收率（IVR）分别为（127.19±44.03）％、（101.78±43.98）％。输注纤维蛋白原后，FIB∶C明显提升，凝血酶时间及凝血酶原时间明显下降，用药24 h后凝血酶时间较基线平均下降（15.2±12.1）％。结论多数先天性纤维蛋白原缺乏症患者症状轻微或无症状；无纤维蛋白原血症患者出血症状较为严重，FIB∶C与出血程度之间存在负相关；基因检测有助于疾病分型诊断；FIB∶C/纤维蛋白原抗原（FIB∶Ag）比值<0.7可作为临床分型依据。凝血酶时间可作为异常纤维蛋白原血症诊断及纤维蛋白原替代治疗的疗效判定依据。

Pharmacokinetic study of Kovaltry in thirty-five pediatric patients aged

Kovaltry (BAY81-8973) is an unmodified full-length factor VIII (FVIII) concentrate that enhances the pharmacokinetic (PK) profiles as compared to some other standard half-life time FVIII concentrates. However, the PK of Kovaltry in haemophiliac patients aged <12years has not been reported previously. To investigate the pharmacokinetics and clinical outcomes of Kovaltry in 35 paediatric patients aged <12years. A total of 35 boys with severe haemophilia A were enrolled from August 2019 to May 2020 in Beijing Children's Hospital. After 72-hour washout, PK tests were performed post-infusion of 50IU/kg Kovaltry in a five-timepoint assay. WinNonlin software was used to generate individual PK parameters. The dose, frequency and bleeding details were collected within the first 6months after switching to Kovaltry from other FVIII concentrates. Compared to the blood group O, patients with blood group non-O showed longer mean half-life (t1/2 ) (p<.01), lower mean clearance (CL) (p=.01) and similar in vivo recovery (IVR) (p=.51). Higher von Willebrand factor antigen (VWF:Ag) level was correlated to longer t1/2 (p<.0001) and lower CL (p<.01). IVR was correlated to body mass index (BMI) (p<.0001). Patients with trough level >3IU/dL demonstrated lower annual bleeding rate (ABR) (p<.01), annual joint bleeding rate (AJBR) (p<.01) and annual spontaneous bleeding rate (ASBR) (p<.01). This study firstly reported the PK profiles of Kovaltry in 35 paediatric patients <12years old. The great inter-individual variability of PK parameters was also confirmed in these patients. VWF:Ag and blood group were major influencing factors of t1/2 and CL of Kovaltry, while BMI was a vital predictor for IVR. Patients with high trough FVIII level in routine prophylaxis had reduced bleeding rates.

Multicentre pharmacokinetic evaluation of rFVIII-Fc (efmoroctocog alfa) in a real life and comparison with non-extended half-life FVIII concentrates.

The use of enhanced half-life (EHL) FVIII has improved the quality of prophylaxis in haemophilia A, but with a benefit that may vary from one patient to another. We analysed the pharmacokinetic data obtained with efmoroctocog alfa (rFVIII-Fc) in 114 patients and, in 47 cases, compared them to those previously measured with non-EHL FVIII. The in vivo recovery (IVR) of rFVIII-Fc measured with one stage clotting assay (OSA) and chromogenic assay (CSA) was 2.2 and 2.8IU/mL per IU/kg, respectively. The median half-life (T1/2 ) of rFVIII-Fc was 14.5hours whatever the FVIII:C assay used, but variable and correlated with preinfusion VWF:Ag levels (r=.76). Both IVR and T1/2 were lower in patients under 12years old (2.4IU/mL per IU/kg and 11.1hours, respectively; CSA). PK study of rFVIII-Fc vs non-EHL FVIII showed a T1/2 ratio of 1.4 in favour of rFVIII-Fc, regardless of the patient's age. However the relative increase in T1/2 with rFVIII-Fc was lower than 30% in one-third of patients evaluated, particularly when the previous FVIII administered was a BHK-derived product. This study therefore suggests that analysis of individual PK profile in response to a specific FVIII concentrate is potentially useful before a switch in haemophilia A patients.

Pharmacoeconomic Analysis of Ideal Vs. Actual Body Weight-Based Treatment for Adult Persons with Hemophilia Α

Introduction: Clotting factor replacement therapy in the management of persons with hemophilia A (PwHA) is typically dosed using the following weight-based formula: Factor VIII (FVIII) Dose = Body weight (BW) in kg X desired FVIII increase (%) 2 This equation is based upon a FVIII in vivo recovery (IVR) of 2, which assumes that each FVIII unit per kg of BW infused will increase the circulating FVIII concentration by 2%. There have been a few studies demonstrating that IVR increases with increasing BW. A pharmacokinetic study performed using recombinant FVIII concentrate for pediatric PwHA &lt;6 years of age found that rising body mass index (BMI) resulted in a linear increase in IVR [Blanchette VS, et al. J Thromb Haemost 2008; 6: 1319-26]. Using data from eight pharmacokinetic clinical trials evaluating three recombinant FVIII concentrates in adult PwHA, Henrard et al. demonstrated that the IVR for an adult cohort consisting of 201 PwHA was 2.16. However, when these patients were stratified based on BMI: &lt;20.3 kg/m2, between 20.3 and 29.5 kg/m2, and &gt;29.6 kg/m2, each group had a significantly different and increasing IVR of 1.60, 2.14 and 2.70, respectively [Henrard S, et al. Haematologica 2013; 98: 1481-6]. As there are no guidelines for dosing of factor replacement therapy for obese PwHA, these studies suggest that ideal body weight (IBW) could be considered instead of actual body weight (ABW) in the dose calculations. With the prevalence of obesity in the hemophilia population now approaching that of the general population, dosing using IBW has potential economic ramifications [Wong TE, et al. Am J Prev Med 2011; 41: S369-75, Majumdar S, et al. Haemophilia 2011; 17: 717-8]. Objectives: 1) To estimate the prevalence of overweight and obese adult persons with hemophilia (PwH) in the state of Utah; 2) To estimate the cost savings for annual prophylactic clotting factor prescriptions if they were to be written using IBW vs. ABW for adult PwHA that are obese in the state of Utah. Methods: Adult PwH (≥18 years of age) who have been seen at least once in the past 3 years (January 1, 2016 to December 31, 2018) were identified from the Utah Center for Bleeding &amp; Clotting Disorders Registry. The following information was collected: Demographics; type of hemophilia; severity of hemophilia; height; weight; BMI. If BMI was not available, this was calculated based on the following equation, BMI = kilograms/meters2. Overweight was defined as a BMI 25 - 29.9 kg/m2. Obese was defined as a BMI ≥ 30 kg/m2. As there is limited data on the relationship between increasing BMI and IVR for factor IX concentrates, persons with hemophilia B were excluded in our cost savings analysis. For PwHA on clotting factor prophylaxis who were obese, the IBW was calculated using their height and the following equation for men: IBW (in kg) = 50 + 2.3 kg per each inch over 5 feet Using the prophylaxis schedule for each obese PwHA, an estimate of the annual cost was calculated using Wholesale Acquisition Cost and compared using both ABW and IBW. Results: A total of 87 adult PwH were seen with documented measurements of height and weight within the past 3 years. The patient characteristics are presented in Table 1. The mean and median age was 37.1 and 34 years, respectively (range: 19 - 75 years). The mean value for BMI was 28.1 and the median was 27.2 (range 17.3 - 46.0). Two patients had class III obesity (BMI ≥40 kg/m2). Almost two-thirds of adult PwH were overweight or obese (58/87; 65.5%). The prevalence of overweight and obese adult PwH in Utah based on age and severity of disease is shown in Figure 1. The estimated annual cost for each of the 12 adult obese PwHA based on their ABW vs IBW is shown in Figure 2. The difference in the total annual cost of treatment for the 12 adult PwHA on prophylaxis factor replacement therapy would be reduced by a total of roughly $2,100,000 if IBW was used rather than ABW; an average savings of $175,000 per adult PwHA per year. Conclusion: The relatively high prevalence of overweight and obesity in the Utah hemophilic population is similar to what has been reported in other states across the United States. The use of IBW in dose calculations has significant economic ramifıcations. Further studies performing individualized pharmacokinetic analysis for PwHA using IBW dosing must be coupled with close clinical monitoring to ensure safety of this dosing strategy before it can be adopted into routine clinical practice. Disclosures Rodgers: Pfizer: Consultancy; Octapharma: Consultancy; Novartis: Consultancy; Sanofi: Consultancy; AstraZeneca: Consultancy.

Pharmacokinetic Studies of Factor VIII in Chinese Boys with Severe Hemophilia A: A Single-Center Study.

Background:Although much attention has been paid to the pharmacokinetics (PKs) of different factor VIII (FVIII) concentrates in persons with hemophilia A (HA), limited information is available in young boys with severe HA. In this study, we aimed to assess the PK parameters of FVIII products in boys with severe HA in China.Methods:A total of 36 boys (plasma-derived [pd]-FVIII, n = 15; recombinant [r] FVIII, n = 21) were enrolled between January 2015 and May 2016 in Beijing Children's Hospital. PK characteristics of FVIII products were studied according to a reduced 4-sampling time point design (1 h, 9 h, 24 h, and 48 h postinfusion).Results:The mean FVIII half-life (t1/2) was 10.99 ± 3.45 h (range 5.52–20.02 h), the mean in vivo recovery (IVR) was 2.01 ± 0.42 IU/dl per IU/kg (range 1.24–3.02 IU/dl per IU/kg) and mean clearance (CL) of FVIII is 4.34 ± 1.58 ml·kg−1·h−1 (range 2.29–7.90 ml·kg−1·h−1). We also analyzed the influence of several parameters that potentially modulate FVIII PK. The age was closely associated with FVIII half-life (R2= 0.32, P < 0.01). The t1/2 of FVIII increased by 0.59 h per year. Besides age, von Willebrand factor antigen (VWF:Ag) also was associated with FVIII half-life (R2= 0.52, P < 0.01). Patients with blood Group O had a shorter FVIII half-life than patients with non-O blood group (9.40 ± 0.68 h vs. 12.3 ± 0.79 h, t = 2.70, P = 0.01). The FVIII IVR correlated with age (R2= 0.21, P < 0.01) and VWF:Ag level (R2= 0.28, P < 0.01). CL rates were faster in young patients and in those with low-VWF:Ag levels. CL rates of FVIII are higher in blood Group O versus non-blood Group O persons (5.02 ± 0.38 vs. 4.00 ± 0.32 ml·kg−1·h−1, t = 2.53, P = 0.02).Conclusions:Chinese boys with severe HA have similar PK values to other ethnic groups and large differences in FVIII PK between individual patients. Age, blood group, and VWF:Ag levels are important determining factors for FVIII CL.

A Lentiviral Fluorescent Genetic Barcoding System for Flow Cytometry-Based Multiplex Tracking

Retroviral integration site analysis and barcoding have been instrumental for multiplex clonal fate mapping, although their use imposes an inherent delay between sample acquisition and data analysis. Monitoring of multiple cell populations in real time would be advantageous, but multiplex assays compatible with flow cytometric tracking of competitive growth behavior are currently limited. We here describe the development and initial validation of three generations of lentiviral fluorescent genetic barcoding (FGB) systems that allow the creation of 26, 14, or 6 unique labels. Color-coded populations could be tracked in multiplex invitro assays for up to 28days by flow cytometry using all three vector systems. Those involving lower levels of multiplexing eased color-code generation and the reliability of vector expression and enabled functional invitro and invivo studies. In proof-of-principle experiments, FGB vectors facilitated invitro multiplex screening of microRNA (miRNA)-induced growth advantages, as well as the invivo recovery of color-coded progeny of murine and human hematopoietic stem cells. This novel series of FGB vectors provides new tools for assessing comparative growth properties in invitro and invivo multiplexing experiments, while simultaneously allowing for a reduction in sample numbers by up to 26-fold.

Retrospective analysis of in vivo recovery and clearance during continuous infusion of recombinant factor VIII products: a single-institution study.

Continuous infusion (CI) of recombinant FVIII (rFVIII) concentrates has been reported as an effective and safe method to achieve haemostasis during major surgeries or severe bleeding events. For more effective and safer CI, better understanding of in vivo recovery (IVR) and clearance (CL) issues is imperative. We investigated the following factors affecting IVR and CL using univariate and multivariate regression analyses during 47 CIs in 34 patients: rFVIII concentrate type, haemophilia severity, blood type, the presence of hepatitis C virus (HCV) or human immunodeficiency virus (HIV), age and body mass index (BMI). The mean IVR was 1.64 ± 0.49 IU dL-1 per IU kg-1 , and the mean CL during CI was 3.56 ± 1.57 mL h-1 kg-1 . The univariate and multivariate regression analyses showed that the CL of octocog alfa was significantly lower than that of rurioctocog alfa (P = 0.043 and 0.0034, respectively). There was a significant difference in BMI in the univariate and multivariate regression analyses (P = 0.0403 and 0.0376, respectively). This study indicated that CL during CI was potentially affected by the type of rFVIII concentrate used and BMI.

Safety and Efficacy of New Nonacog Alfa Drug (Innonafactor) in Prophylactic Treatment in Patients with Severe and Moderate Hemophilia B

During a controlled, randomized, open, prospective, multicenter clinical trial the efficacy and safety of a new domestically produced recombinant factor IX (FIX, nonacog alfa, CJSC "GENERIUM", Russia) were investigated in comparison with plasma drug Octanine® F (filtered) ("Octapharma pharmazeutika produktionsges mbH", Austria) for the prophylactic treatment of bleedings in patients with severe and moderate hemophilia B. After screening and a 4-day washout period 18 patients with moderate (n=8) and severe (n=10) hemophilia B were divided into 2 groups according to randomization: the 1st group patients (n=9) received the nonacog alfa, the 2nd group (n=9) Octanine F (fig. 1). In the 1st group there were 4 patients with severe hemophilia B (activity of FIX was less than 1%) and 5 patients with the moderate form of the disease (activity of FIX was 1-3%). In the 2nd group 6 patients had severe and 3 moderate hemophilia B (activity of FIX was 1-2,6%). In order to prevent bleeding nonacog alfa was injected slowly intravenously at a dose of 50±5 IU kg-1. Octanine F was infused at a dose of 30±5 IU kg-1. Drugs were injected 2-3 times per a week during 26±1 weeks (6 months). The main criterion of drug efficacy was the average number of bleedings within 6 months of prophylactic treatment. Anticipated average number of bleedings was determined based on the effectiveness of the original drug Benefix® (Pfizer, USA) and was 9±3 cases. Additional criteria of efficacy were severity of bleeding, activated partial thromboplastin time (APTT) and FIX activity before and 30 min after drug administration compared with normal values.In the 1st group 2 moderate bleeding episodes occurred in 2 patients, while in the 2nd group 10 hemorrhagic episodes occurred in 4 patients (1 episode was severe, 1 - moderate, and 8 were low grade). There were no significant differences in frequency of bleeding events.The average number of bleedings during the analyzed period in patients of the 1st group was 0,22±0,44. In patients of the 2nd group it was 1,11±1,97; the differences were statistically insignificant (p=0,24).In patients of both groups, the average number of bleeding was within planned range (fig. 2).Pharmacokinetics was evaluated by K-value (incremental recovery) and in vivo recovery (IVR).After carrying out of prophylactic therapy during 6 months, Incremental recovery of nonacog alfa was 1,24 ± 0,32 IU/DL per IU/kg. The Incremental recovery (K-value) of Octanine F was analogous and amounted to 1,14 ±0,29 IU/DL per IU/kg.During 6 months IVR of nonacog alfa was 47,56 ±13,56% and the IVR of Octanine F was not different and amounted to 49,05 ±15,68%.Prophylactic therapy was accompanied by normalization of coagulation activity of blood. On the 26th week of therapy APTT values taken 30 minutes after drug administration were 38,04 ±3,63 sec. in 1st group and 41,49 ± 3,44 sec. in the 2nd group.Safety assessment was performed in 18 patients. There were 6 adverse events in the 1st group and 12 in the 2nd group. All adverse events were not associated with drugs administration. Thus, the study shows that nonacog alfa (Innonafactor) is effective in prophylaxis of bleeding in patients with severe and moderate hemophilia B. The results are comparable with the results of the use of Octanine F.The study demonstrated that nonacog alfa (Innonafactor) with its pharmacodynamic and pharmacokinetic characteristics is comparable to Octanine F. Administration of nonacog alfa (Innonafactor)to patients with severe and moderate hemophilia B was accompanied by normalization of APTT and FIX activity and rising activity of FIX and its degree of recovery. Treatment with nonacog alfa (Innonafactor) was safe and without side effects, infection transmission, de novo inhibitor incident. [Display omitted] [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

Surgery in Von Willebrand Disease (VWD) Is Facilitated By a Novel 1:1 Plasma Derived Human Factor VWF/VIII Concentrate

▪This novel plasma derived, double viral attenuated VWF/FVIII concentrate with a ratio of 1:1 between both coagulant proteins (Wilate) was utilized in a pivotal clinical study conducted to further investigate its clinical efficacy and safety in VWD patients requiring surgery.This was a prospective, open-label, uncontrolled, multi-center, phase III clinical study. The primary objective was to evaluate the overall hemostatic efficacy of Wilate in preventing excessive intra- and post-operative bleeding in pediatric and adult patients with VWD. Forty–one patients, 20 major and 10 with Type 3 VWD, were planned to be enrolled to document 41 surgical procedures. During the planned interim analysis after 30 procedures, a pre-specified success rate for study termination was reached and the study was stopped early as determined by an independent data and safety monitoring board (IDMC). In vivo recovery (IVR) was investigated in all patients at the beginning of the study for pre- and post-surgical dosing. Hemostaticefficacy was assessed for each case intra- and post-operatively by the surgeons and hematologists independently, utilizing objective 4-point ordinal efficacy scales. This assessment was additionally adjudicated by the IDMC. Safety and immunogenicity were monitored throughout the study.Twenty-eight individual patients, who underwent 30 surgeries, were enrolled from 14 sites in 8 countries in Europe, Asia, and the USA. Of the 30 procedures (2 patients had more than 1 procedure), 7 had VWD Type 1 unresponsive to DDAVP (23.3%); 2 had VWD Type 2 (6.7%, one with Type 2A and one with Type 2B), and 21 had severe VWD Type 3 (70.0%). Age at baseline ranged from 12 to 74 years (median 36 years), with 3 adolescents (younger than 18 years of age) included in the study. Most surgeries were either orthopedic (10 surgeries) or dental (7 surgeries). Five surgeries were obstetric/gynecological; 4 were gastrointestinal; 3 of the ear, nose or throat; and one was ophthalmologic. In total 21 major surgeries and 9 minor surgeries were performed. Of the 21 severe VWD Type 3 patients, 17 underwent major surgery and 4 underwent minor surgery. The mean loading dose of VWF/FVIII concentrate (Wilate) per infusion (measured in VWF:RCo units) was 55.5 IU/kg for major surgeries and 37.5 IU/kg for minor surgeries. The mean maintenance dose was 30 IU/kg for major and 20.6 IU/kg for minor surgeries. Mean FVIII:C and VWF:RCo peak plasma activity levels of each patient during the maintenance infusions (infusion 1 post surgery to infusion 7), ranged from 119 IU/dL – 138 IU/dL and 66 IU/dL - 92 IU/dL, respectively, and were stable over time with no accumulation of FVIII:C (Figure 1). In the 30 procedures patients received a mean total dose (VWF:RCo) of Wilate of 434.2 ± 271.2 IU/kg (29,086 ± 17,932 IU).The overall treatment with Wilate was successful in 29 out of 30 surgeries (rate 0.967; 98.75 CI: 0.784, 1.000). Nine of 9 minor surgeries (success rate 1.000; 98.75% CI: 0.569, 1.000), and 20 of 21 major surgeries (success rate 0.952; 98.75% CI: 0.704, 1.000), were successful, as were all 21 surgeries in patients with Type 3 VWD (success rate 1.000; 98.75% CI: 0.785, 1.000).None of the patients experienced excessive intra- or post-operatively bleeding that was uncontrolled or required an alternate VWF/FVIII concentrate. No incidences of thrombotic events were reported despite 1/3 of the surgeries being orthopedic and high risk for such in non-coagulopathic populations.No FVIII or VWF neutralizing inhibitors or study drug related serious adverse events (SAEs) were observed. [Display omitted] Numbers above the graph indicate the number of observations at each dosing pointConclusion: Results of this study showed that more than 96% of the study’s surgeries treated prophylactically with Wilate were rated as having excellent or good hemostatic efficacy, as adjudicated by the IDMC. The study was terminated early because of clear and robust demonstration of efficacy, as pre-specified in the protocol. There was no accumulation of FVIII:C activity after repeat dosing. No cases of VWF or FVIII:C inhibitors, thrombotic events, or related SAEs were observed. DisclosuresSrivastava:Octapharma: Consultancy, Other. Off Label Use: Wilate is a Human VWF/FVIII product licensed in the US for treatment of acute bleeding in VWD patients but not licensed for prophylactic treatment in surgical procedures. Werner:Octapharma: Employment. Schwartz:Octapharma: Employment. Knaub:Octapharma: Employment.

Efficacy, Immunogenicity, Pharmacokinetics, and Safety Of Human-cl rhFVIII – a GCP Study In Children With Severe Haemophilia A

IntroductionHuman-cl rhFVIIIis the first recombinant factor VIII concentrate expressed in a human cell line (Human Embryonic Kidney 293F cells). Studies in adolescent and adult pre-treated patients with severe haemophilia A showed a favorable PK profile with a median half-life of 17.1 hours (one stage assay) and indicated safety and efficacy in preventing and treating bleeding episodes (BE). AimsThe objectives of this international GCP study were to evaluate the efficacy, safety, immunogenicity and pharmacokinetic (PK) properties of Human-cl rhFVIIIin previously treated children between 2 and 12 years of age. MethodsAll patients started with an in-vivo recovery (IVR) investigation and in a subset of patients, the PK of Human-cl rhFVIII was assessed in comparison to the patient's previously used FVIII product. After an injection of 50 IU/kg, blood samples were collected up to 48 hours for PK analysis and up to 2 hours for IVR. IVR was repeated in all patients after 3 and 6 months. FVIII plasma levels were measured by chromogenic and one-stage assay in a central laboratory. Patients were treated prophylactically with Human-cl rhFVIII every other day or 3x weekly, injecting 30-40 IU Human-cl rhFVIIIper kg for at least 6 months and > 50 exposure days. Inhibitors were measured before, during and at the end of the study by modified Nijmegen Bethesda assay in a central laboratory. Adverse events were recorded throughout the study. Results59 patients (29: 2-5 years; 30: 6-12 years) were enrolled from 15 specialized sites in Europe. 13 children of each age group participated in the comparative PK investigation. Mean PK parameters of Human-cl rhFVIII were similar in both age groups for both the chromogenic and the one-stage assay: AUCnorm 0.23 vs. 0.24 h*IU/mL/[IU/kg]); IVR 1.88 vs. 1.61% per IU/kg; T1/2 9.7 vs. 12.5 h. IVR remained stable throughout the study. A total of 108 BEs in 32/59 patients were treated with Human-cl rhFVIII. The majority of treated BEs were traumatic (60.2%) and minor (56.5%). The mean ± SD monthly bleeding rate of all types of BEs/patient was 0.34±0.43 (spontaneous BEs: 0.12±0.27; traumatic BEs: 0.19±0.29). No inhibitor development was reported; no patient discontinued the study because of an AE. ConclusionThe data indicate that Human-cl rhFVIII is efficacious and safe in preventing and treating BEs in previously treated children. The PK of Human-cl rhFVIII was comparable in both studied age groups. Disclosures:Liesner:Octapharma AG: Consultancy, Investigator Other. Jansen:Octapharma AG: Employment. Klukowska:Octapharma AG: Investigator Other. Vdovin:Octapharma AG: Investigator Other. Szczepanski:Octapharma AG: Investigator Other. Knaub:Octapharma AG: Employment.

Efficacy and safety of Wilate in paediatric VWD patients under 6 years of age - results of a prospective multicentre clinical study including recovery information

Treatment with exogenous von Willebrand factor (VWF) is indicated in patients with von Willebrand disease (VWD) in whom treatment with 1-deamino-8-d-arginine vasopressin/desmopressin is contraindicated. Wilate is a new generation plasma-derived concentrate of native VWF and coagulation factor VIII (FVIII) (in a physiological 1:1 ratio) developed for the treatment of VWD. This is the first study to report safety, efficacy and in vivo recovery (IVR) data from 15 paediatric patients less than 6 years of age who received Wilate for either prophylaxis, on-demand treatment or for treatment in surgical procedures during a prospective open-label trial (VWD type 1: 5, type 2A: 1, type 2B: 2, type 3: 6, unknown type: 1 patients). Analysis of IVR for VWF and FVIII suggested an appropriate and consistent rise in coagulation activity after Wilate administration. Overall efficacy was rated as excellent or good for 99.7% [prophylactic infusions] and 100% [bleeding episodes/surgical procedures]. More than 82% of bleeding episodes resolved after 1 day of treatment, and a Wilate dosage of 20-50 IU kg(-1) was sufficient to achieve haemostasis in 97% of bleeding episodes. All surgical procedures were successfully managed with Wilate. No thromboembolic events were observed during the study, and no patient developed anti-VWF antibodies or FVIII inhibitors. In conclusion, this study confirms both the expected IVR profile in paediatric patients and the excellent efficacy, tolerability and safety profile of Wilate observed previously in adults. Wilate showed excellent efficacy in the treatment of bleeding when used prophylactically or on-demand, and in the treatment of surgical procedures.

Head-to-head comparison of the pharmacokinetic profiles of a high-purity factor IX concentrate (AlphaNine®) and a recombinant factor IX (BeneFIX®) in patients with severe haemophilia B

Head-on comparative studies of factor IX (FIX) concentrates performed under standardized conditions are rarely conducted regardless of being a valuable instrument guiding health care providers towards better informed and cost-effective decisions. This study is an extension of a multicentre study that assessed the efficacy, safety and pharmacokinetics (PK) of AlphaNine(®) in 25 previously treated patients with severe haemophilia B (FIX:C ≤ 2%). After a washout period ≥ 7 days following the last PK performed with AlphaNine(®) after a dose of 65-75 IU kg(-1) , an identical PK study was performed with BeneFIX(®) on 22 of the same patients. Venous blood samples for analysis were taken at baseline and at 0.25, 0.5, 1, 3, 6, 9, 24, 48, 72 and 74 h post infusion. The outcomes of the comparison of the PK parameters were as follows: Mean (± SD) in vivo recovery (IVR) was 1.3 ± 0.4 IU dL(-1) per IU kg(-1) for AlphaNine(®) and 1.0 ± 0.3 IU dL(-1) per IU kg(-1) for BeneFIX(®) (P < 0.01). Mean terminal half-life, mean residence time, area under the curve, clearance and volume of distribution of BeneFIX(®) were 36.0 ± 12.8 h, 39.3 ± 13.9 h, 1631 ± 467 IU h dL(-1) , 0.046 ± 0.01 dL kg(-1) min(-1) and 1.75 ± 0.52 mL kg(-1) respectively. These values were not significantly different to those observed in AlphaNine(®), although BeneFIX(®) displayed higher than expected IVR values and lower than expected clearance values. In conclusion, AlphaNine(®) showed a comparable half-life, but an IVR significantly higher than that of BeneFIX(®). This dissimilarity may have implications on dosing requirements for on-demand treatment regimes affecting optimal resource allocation.

Pre-Clinical Characteristics of a Recombinant Fusion Protein Linking Activated Coagulation Factor VII with Albumin (rVIIa-FP)

AbstractAbstract 1115Recombinant factor VIIa (rFVIIa) is approved to control bleeding in hemophilia A and B patients who have developed inhibitory antibodies to replacement therapy and in acquired hemophilia. rFVIIa is rapidly eliminated with a terminal half-life of approximately 2.5 hours in humans. This short half life necessitates frequent injections and considerably limits prophylactic use. A recombinant fusion protein linking activated factor VII with albumin (rVIIa-FP) was engineered to extend the half life of rFVIIa.The present studies were conducted to gather knowledge about the pharmacokinetic and pharmacodynamic (PK/PD) properties of rVIIa-FP in preclinical animals models to enable a more precise estimate of the procoagulant activity of rVIIa-FP for the future clinical use in haemophilia patients with inhibitors to FVIII and FIX. Single intravenous doses of either rVIIa-FP or the licensed rFVIIa comparator, NovoSeven® were administered to mice, rabbits and monkeys. Subsequently, plasma samples were harvested at different time-points after study drug administration and systemic levels of rVIIa-FP or NovoSeven® were assessed either by FVIIa activity measurements using the Staclot® assay system or by FVII antigen measurements using an enzyme linked immunoabsorbance assay (ELISA). When investigating dose responses or duration of hemostatic activity, rVIIa-FP and NovoSeven® were administered to mice or rabbits before tail clip or induction of venous stasis, respectively. Following a single intravenous bolus application the procoagulant activity of both study drugs was assessed in both models at different time points after administration up to 24 hours to proof prolonged procoagulant effects of rVIIa-FP compared to NovoSeven®.Intriguingly, in all animal species tested the systemic bioavailability, clearance and in addition the terminal half-life (t1/2β), of rVIIa-FP were significantly better in comparison to NovoSeven®. Based on FVIIa activity measurements in plasma samples derived from monkeys the 11 fold higher area under the curve (AUC) was accompanied with a 4-fold longer t1/2β, while in vivo recovery (IVR) of rVIIa-FP exceeded that of NovoSeven® by a 70 %. In rabbits the 20 fold higher AUC was associated with a 5-fold longer t1/2β and a 4-fold higher IVR when measuring specific FVIIa activity. In mice measurements of FVII antigen revealed a 11 fold higher AUC, while t1/2β was 4 times longer and IVR was found to be doubled in comparison to NovoSeven®. The assessment of pharmacodynamic activity after dosing based on specific FVIIa activity adjusted by the Staclot® assay revealed, that the procoagulant effect of rVIIa-FP was not different from NovoSeven®, when measuring total blood loss under acute bleeding conditions after tail clip. However, when assessing late time-points after treatment the prolonged systemic availability of rVIIa-FP translated into a longer and sustained hemostatic activity of rVIIa-FP compared to NovoSeven® in both animal models. Intriguingly, ex vivo studies in hemophilia A mice showed that the 4 fold prolonged systemic availability of rVIIa-FP in plasma translates into sustained FVIIa activity when recorded as thrombin generation activity compared to NovoSeven® at 16 hours after treatment. Furthermore in rabbits, the 5 fold longer half-life translated into a significantly greater procoagulant activity as measured by thrombus formation in both jugular veins after venous stasis.In conclusion, the recombinant albumin fusion technology was successfully applied to human recombinant FVIIa for a significantly improved of PK/PD profile as observed in different pre-clinical animal species. Future clinical studies can proof whether the observed improved PK/PD characteristics will also translate into a half-life extension and a longer hemostatic effect in hemophilia patients with inhibitors to FVIII and FIX.Allowed: The entire body of the abstract, including text and tables, must not exceed 3,800 characters. Spaces are not included in this number; title, authors' names, and affiliations are counted separately. Figures are not included in the character count. Disclosures:Zollner:CSL Behring GmbH: Employment. Schuermann:CSL Behring GmbH: Employment. Raquet:CSL Behring GmbH: Employment. Mueller-Cohrs:CSL Behring GmbH: Employment. Weimer:CSL Behring GmbH: Employment. Pragst:CSL Behring GmbH: Employment. Dickneite:CSL Behring GmbH: Employment. Schulte:CSL Behring GmbH: Employment.

Human-Cl Rhfviii Effectively and Safely Prevents Bleeding Episodes in Previously Treated Adult Patients with Severe Haemophilia A

AbstractAbstract 1132The main purpose of this prospective, multi-center, open-label phase 3 study was to assess the efficacy of prophylactic treatment with Human-cl rhFVIII, the first human cell-line derived recombinant FVIII, in previously treated patients (PTPs) with severe haemophilia A.Patients were to receive 30–40 international units (IU) FVIII of Human-cl rhFVIII per kg every other day for 6 months. Efficacy of preventing and treating bleeds were judged using objective criteria taking the monthly bleeding rate and the number of infusions needed to manage a break-through bleed into account. In-vivo recovery (IVR) was determined at the beginning of the study and after 3 and 6 months. FVIII:C was measured by validated chromogenic (CHR) and one-stage (OS) assays in a central laboratory, which also assigned drug potencies. Inhibitor activity was determined using the Nijmegen modification of the Bethesda assay before the first administration and at defined intervals thereafter. Thirty-two patients between 18 and 75 years of age were enrolled from 11 centres in Europe and treated prophylactically for 6.0±0.9 months (mean ± SD) with a mean prophylactic dose of 32.8 IU/kg. Sixteen patients never bled, 11 patients bled once and 5 more than once. The mean total and spontaneous monthly bleeding rate was 0.188±0.307 and 0.095±0.211, respectively. Efficacy of the prophylactic treatment was “excellent” in all patients for spontaneous BEs and “excellent” or “good” in all patients but one for all types of bleeds. All treatments of bleeds were rated as “excellent” (71.4%) or “good” (28.6%). The IVR at baseline was 2.6±0.5 % per IU/kg for the CHR and 2.2±0.5 % per IU/kg for the OS assay and remained stable during the study. A total of 2921 infusions were given in the study. Human-cl rhFVIII was well tolerated and no patient experienced a related serious adverse event. No FVIII inhibitors were detected. Conclusion:The data indicate that Human-cl rh FVIII is safe and efficacious in preventing and treating bleeds in PTPs with severe haemophlia A. Disclosures:Knaub:Octapharma AG: Employment. Lissitchkov:Octapharma AG: PI Other. Tuddenham:College London: Consultancy, Employment, Gene therapy for hemophilia A, Gene therapy for hemophilia A Patents & Royalties, Research Funding. Collins:Octapharma AG: Consultancy. Oldenburg:d and e: Baxter, Bayer, Biotest, CSL-Behring, Grifols, Inspiration, NovoNordisk, Octapharma, Pfizer e: Biogen IDec, Swedish Orphan Biovitrum: Honoraria, Research Funding. Bichler:Octapharma AG: Employment.

IB1001, an Investigational Recombinant Factor IX, Pharmacokinetics in Pediatric Patients with Hemophilia B.

AbstractAbstract 2225 IntroductionIB1001 is a recombinant factor IX product being investigated for the treatment and prevention of bleeding in individuals with hemophilia B. Pharmacokinetics (PK) in adults (>12 years) demonstrated that IB1001 had results similar to the currently available recombinant FIX with respect to parameters such as terminal phase half-life and incremental recovery.We report the interim findings from a PK assessment in children <12 years, with severe hemophilia B (FIX <2%), >50 prior exposure days to FIX, and no history of or currently detectable inhibitor to FIX. MethodsNon-randomized, open-label PK study with patients receiving 75±5 IU/kg of IB1001 following a washout period of ≥4 days from a previous FIX infusion. Factor IX levels were determined pre-infusion and at 15–30 minutes, 4–6, 24–26, and 68–72 hours post-infusion. Additional samples could be drawn at 1–3 and 10–14 hours.Calculated PK parameters were: half-life (β-phase t1/2, determined using a robust regression approach [Lee ML et al. XVIth ISTH Congress, Florence, Italy, 1997]) but generally assuming a single compartmental model because of the small number of points, maximum plasma concentration (Cmax), in vivo recovery (IVR) and AUC(0-∞) (determined by the trapezoidal rule). In addition, the AUC(0-t) and mean residence time (MRT) were calculated. ResultsSubjectt 1/2 α (hr)t 1/2 β (hr)MRT (hr)Cmax (IU/dl)In vivo Recovery (IU/dl)AUC0-∞ (IU/dl/hr)AUC0-t (IU/dl/hr)Age (years)Subjects 6 - 12 Years of Age32001n/a17.722630.8414611359912001n/a17.521.2570.76113810627.532003720.724580.77106797711.135002n/a33.655220.2960541010mean±SD (median)22.4±7.6 (19.2)30.6±16.3 (23)50±19 (57.5)0.66±0.25 (0.765)1068±353 (1102.5)952±397 (1019.5)9.4±1.5 (9.5)Subjects < 6 Years of Age4001n/a7.612.1600.8942941235001n/a16.319.5640.8512171147432002n/a21.929.4400.539868704.5mean±SD (median)15.3±7.2 (16.3)20.3±8.7 (19.5)55±13 (60)0.73±0.17 (0.8)1048±148 (986)986±144 (941)3.5±1.3 (4)When compared to the findings previously reported with IB1001 in adult (≥12 years of age) subjects (Martinowitz U et al. Haemophilia, 18, 2012), the results in pediatric patients demonstrate a more rapid metabolism of factor IX as is indicated by the shorter terminal half-life (mean±SD of 19.3±7.8 h versus 29.6±18.2 h in adults) and the smaller AUC0-∞ (mean±SD of 1059±264 versus 1668±598 in adults). In addition, the in vivo recovery was lower (mean±SD of 0.69±0.21) versus that seen in adults (mean±SD of 0.98±0.22). These results are similar to those reported by Berntorp et al (Haemophilia, 7, 2001) with nonacog alfa. ConclusionsThe pharmacokinetics of IB1001 has previously been shown to be non-inferior to nonacog alfa, another recombinant factor IX, in hemophilia B individuals >12 years of age. The current study is intended to provide information on children <12 and, particularly, <6 years of age. IB1001 is metabolized faster and has a lower recovery than the comparable findings in patients >12 years of age. Although the study is ongoing, these may represent important implications for the potential use of IB1001 in pediatric patients. Disclosures:Gomperts:Inspiration Biopharmaceuticals Inc: Consultancy. Apte:Inspiration Biopharmacauticals Inc: Research Funding. Chaudhuri:Inspiration Biopharmaceuticals Inc: Research Funding. John:Inspiration Biopharmaceuticals Inc: Research Funding. Ramanan:Inspiration Biopharmaceuticals Inc: Research Funding. Liesner:Inspiration Biopharmaceuticals Inc: Research Funding. Shapiro:Inspiration Biopharmaceuticals Inc: Honoraria, Research Funding. Mills:Inspiration Biopharmaceuticals Inc: Employment. Lee:Inspiration Biopharmaceuticals Inc: Employment.