Jerzy Windyga

Institute of Hematology and Blood Transfusion, Warsaw, Warszawa, Masovian Voivodeship, Poland

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Publications (73)216.24 Total impact

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    ABSTRACT: In the phase 3 B-LONG [Recombinant Factor IX Fc Fusion Protein (rFIXFc) in Subjects with Haemophilia B] study, rFIXFc dosed every 1–2 weeks was safe and efficacious in previously treated subjects with haemophilia B. To date, there are no evaluations of transitioning from conventional to long-acting factor IX (FIX) prophylaxis. This post-hoc analysis of B-LONG subjects compared prophylaxis with other FIX products and rFIXFc. Pre- and on-study data were analysed to assess dosing regimen, weekly FIX consumption and annualized bleeding rates (ABRs). Population pharmacokinetics models were used to generate FIX activity profiles with rFIXFc and recombinant FIX prophylaxis. Thirty-nine subjects, previously treated prophylactically, were evaluated. Prior to study, most subjects (69·2%) received twice-weekly FIX infusions; on study, subjects infused rFIXFc once every 1–2 weeks with c. 30–50% reductions in weekly consumption. On-study estimated mean ABRs were lower than pre-study estimated mean ABRs. Models predicted that rFIXFc administered 50 iu/kg weekly and 100 iu/kg every 10 d would maintain steady-state FIX trough levels ≥1 iu/dl in 95·4% and 89·2% of subjects, respectively. These results indicate that patients receiving rFIXFc prophylaxis can markedly reduce infusion frequency and FIX consumption, have a greater likelihood of maintaining FIX activity >1 iu/dl and experience fewer bleeding episodes compared with prior FIX prophylaxis.
    British Journal of Haematology 09/2014; · 4.94 Impact Factor
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    ABSTRACT: Vatreptacog alfa, a recombinant factor VIIa (rFVIIa) analogue with three amino acid substitutions and 99% identity to native factor VIIa, was developed to improve the treatment of patients with hemophilia and inhibitors.
    Journal of Thrombosis and Haemostasis 06/2014; · 6.08 Impact Factor
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    ABSTRACT: Individuals with hemophilia B experience frequent and spontaneous bleeding episodes into joints and muscles that can lead to severe arthropathy, chronic pain, disability, and diminished quality of life (QoL). Prophylaxis with factor nine (FIX) concentrates may reduce the frequency of bleeding events and improve QoL. Recombinant FIX (rFIX) concentrates are a potentially safer treatment option than plasma-derived FIX products with respect to pathogen transmission risk, but until recently, only one licensed rFIX product was available. We describe a newly approved rFIX concentrate, BAX326 (RIXUBIS; Baxter Healthcare Corporation). Phase III studies of BAX326 demonstrated its efficacy and safety in prophylactic, on-demand, and surgical settings and showed that its pharmacokinetic properties were comparable to those of the licensed comparator. Importantly, prophylaxis with BAX326 significantly improved physical health-related QoL, demonstrating that this new rFIX treatment that has the potential to improve outcomes in hemophilia B patients.
    Expert Review of Hematology 06/2014; 7(3):333-42. · 2.38 Impact Factor
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    ABSTRACT: Post-transplant lymphoproliferative disorders (PTLD) is a serious complication following solid organ transplantation or allogeneic hematopoietic stem cell transplantation (allo-HSCT). Pathogenesis of PTLD indicates a strong association with Epstein-Barr virus (EBV) infection. Clinical improvement is observed with reduction in immunosuppression intensity alone or administration of immuno-, chemo- and radiotherapy. We present a case of a 32-year-old man with EBV-associated PTLD as mononucleosis-like syndrome according to the 2008 World Health Organization classification with central nervous system involvement and presence of lupus anticoagulant (LA) following allo-HSCT, where decreasing the immunosuppression was not possible because of concurrent graft versus host disease (GvHD). In this situation rituximab and foscarnet in combination with immunosuppressive therapy improved PTLD and GvHD; at the same time disappearance of lupus anticoagulant was observed.
    Hematologia. 05/2014; 5(1):81-88.
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    Blood transfusion = Trasfusione del sangue 05/2014; 12(Suppl 3):s515-s518. · 1.86 Impact Factor
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    ABSTRACT: Haemostatic management of haemophilia B patients undergoing surgery is critical to patient safety. The aim of this ongoing prospective trial was to investigate the haemostatic efficacy and safety of a recombinant factor IX (rFIX) (Bax326)† in previously treated subjects (12–65 years, without history of FIX inhibitors) with severe or moderately severe haemophilia B, undergoing surgical, dental or other invasive procedures. Haemostatic efficacy was assessed according to a predefined scale. Blood loss was compared to the average and maximum blood loss predicted preoperatively. Haemostatic FIX levels were achieved peri- and postoperatively in 100% of subjects (n = 14). Haemostasis was ‘excellent’ intraoperatively in all patients and postoperatively in those without a drain, and ‘excellent’ or ‘good’ at the time of drain removal and day of discharge in those with a drain employed. Following the initial dose, the mean FIX activity level rose from 6.55% to 107.58% for major surgeries and from 3.60% to 81.4% for minor surgeries. Actual vs. predicted blood loss matched predicted intraoperative blood loss but was equal to or higher than (but less than 150%) the maximum predicted postoperative blood loss reflecting the severity of procedure and FIX requirements. There were no related adverse events, severe allergic reactions or thrombotic events. There was no evidence that BAX326 increased the risk of inhibitor or binding antibody development to FIX. BAX326 was safe and effective for peri-operative management of 14 subjects with severe and moderately severe haemophilia B.
    Haemophilia 04/2014; · 3.17 Impact Factor
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    ABSTRACT: Little is known about the health-related quality of life (HRQoL) burden of haemophilia B. The aim of this study was to assess HRQoL burden of haemophilia B, the benefit of recombinant factor IX (rFIX) prophylaxis and the HRQoL benefit of achieving a zero annual bleed rate. Subjects receiving rFIX (BAX326) prophylaxis or on-demand completed the SF-36 survey. Baseline SF-36 scores were compared to the general US population scores to understand the HRQoL burden. Changes in SF-36 scores between baseline and follow-up were tested using t-tests. Subgroup analysis was conducted to examine SF-36 change among subjects who switched to BAX326 prophylaxis. SF-36 scores were also compared between those with zero bleeds and those who bled during the study. Compared to the US norms, subjects reported lower average scores in all physical and several mental HRQoL domains. At follow-up, prophylaxis subjects reported statistically significant and clinically meaningful improvements in overall physical HRQoL, as measured by the Physical Component Score (PCS) (mean change 2.60, P = 0.019), Bodily Pain (BP) (3.45, P = 0.015) and Role Physical (RP) domains (3.47, P = 0.016). Subjects who switched to prophylaxis from intermittent prophylaxis or on-demand experienced more pronounced improvements not only in the PCS (3.21, P = 0.014), BP (3.71, P = 0.026), RP (4.43, P = 0.008) but also in Vitality (3.71, P = 0.04), Social Functioning (5.06, P = 0.002) and General Health domains (3.40, P = 0.009). Subjects achieving zero bleeds reported lower BP (P = 0.038). Prophylaxis with BAX326 significantly improved HRQoL in patients with moderately severe or severe haemophilia B by reducing bleeds.
    Haemophilia 11/2013; · 3.17 Impact Factor
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    ABSTRACT: Patients with severe haemophilia A experience frequent and spontaneous bleeding, causing debilitating damage to joints and decreasing quality of life. Prophylaxis with factor VIII (FVIII) reduces joint damage if initiated early. Circulating FVIII levels may be influenced by endogenous von Willebrand factor (VWF), a chaperone protein that binds and stabilizes FVIII. The aim of this study was to determine whether endogenous VWF antigen (VWF:Ag) levels are correlated with FVIII pharmacokinetic (PK) parameters and clinical outcomes in patients with severe haemophilia A. Previously treated, non-inhibitor patients in a multinational, randomized, double-blind, Ph II study received prophylaxis with once-weekly BAY 79-4980 (35 IU kg(-1) ) or thrice-weekly recombinant sucrose-formulated FVIII (rFVIII-FS; 25 IU kg(-1) ). PK parameters were evaluated at weeks 1 and 26. The number of bleeds per patient during the study was captured as part of the core efficacy endpoint. Spearman rank correlations assessed relationships of VWF:Ag levels with patient age, PK and annualized bleeding rate. Of 131 study patients (aged 13-64 years; BAY 79-4980, n = 63; rFVIII-FS, n = 68), 27 (21%; n = 15 and 12 respectively) were evaluable for PK assessment. Baseline VWF:Ag levels correlated with patient age (P < 0.0001). There was no significant difference in PK results between treatments; thus, PK parameters and VWF levels of all patients were analysed together. AUCnorm and T1/2 significantly increased with increased VWF:Ag (P < 0.001); clearance significantly decreased with increased VWF:Ag (P = 0.002). Annualized bleeding rate in patients treated with 3× per week rFVIII-FS significantly correlated with VWF:Ag and age (P = 0.038 and 0.021 respectively). PK parameters as well as the clinical outcome significantly correlated with endogenous VWF:Ag. The improved clinical outcome in subjects with high VWF:Ag levels may be explained by VWF:Ag influence on FVIII PK.
    Haemophilia 11/2013; · 3.17 Impact Factor
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    ABSTRACT: Background. Spontaneous intraarticular bleeds in congenital coagulation disorders result in early and extensive damage to the joints and periarticular structures. Total arthroplasty is the only effective method of treating these defects. Interim surgical procedures (arthroscopy, osteotomy, etc.) exist that can postpone arthroplasty, especially considering the fact that the condition affects young people. The aim of this paper is to discuss the range of trauma care and orthopedic procedures performed in patients with congenital coagulation disorders. Also presented are early results of joint arthroplasty in these patients. Material and methods. A total of 168 trauma care and orthopedic procedures were performed in patients with congenital coagulation disorders at the Clinical Department of Orthopedics and Traumatology of the Central Clinical Hospital of the Ministry of Interior in Warsaw in the years 2010-2013. Among them were total arthroplasties (79 arthroplasties of the knee, 30 of the hip, 3 of the ankle and 1 of the elbow), arthroscopies, filling bone cysts with grafts and trauma procedures. The HHS, KSS, AOFAS and MEPS scales were used to evaluate the respective clinical results of hip, knee, ankle and elbow arthroplasty procedures. A VAS was used to evaluate pain intensity. In knee arthroplasty patients, quality of life parameters were evaluated with the WOMAC index. Results. In patients post hip arthroplasty, HHS scores increased by 50.22 points and VAS scores increased by 6.34 points. An increase of 116.41 points in KSS scores and 6.67 points in VAS scores was recorded in patients after knee arthroplasty. Also, WOMAC scores improved by 53.8 points after surgery. Evaluation of early results of ankle arthroplasty in the AOFAS scale showed a mean improvement of 35.5 points and a 5-point improvement in VAS scores. MEPS scores, used for evaluation of elbow arthroplasty results, improved from 15 to 70 points, with an improvement from 6 to 2 points in VAS scores. Conclusions. 1. Orthopedic procedures in patients with congenital coagulation disorders require thorough preparation of the patient and close cooperation between the orthopedic and hematological teams. 2. Early clinical outcomes are promising. 3. Decreased pain intensity, increased joint range of motion and improved quality of life post-surgery are observed.
    Ortopedia, traumatologia, rehabilitacja. 10/2013; 15(6):601-16.
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    ABSTRACT: BAX326 is a recombinant factor IX (rFIX; nonacog gamma) manufactured without the addition of any materials of human or animal origin, and with two viral inactivation steps (solvent/detergent treatment and 15 nm nanofiltration). The aim of this prospective trial was to investigate the pharmacokinetics, haemostatic efficacy and safety of BAX326 in previously treated patients aged 12-65 years with severe or moderately severe haemophilia B. BAX326 was safe and well tolerated in all 73 treated subjects; adverse events considered related to treatment (2.7% incidence, all non-serious) were transient and mild, and no hypersensitivity reactions, inhibitor formation or thrombotic events were observed. Pharmacokinetic (PK) equivalence (n = 28) between BAX326 and a licensed rFIX was confirmed in terms of the ratio of geometric mean AUC0-72 h per dose. Twice-weekly prophylaxis [mean duration 6.2 (±0.7) months; 1.8 (±0.1) infusions per week, 49.5 (±4.8) IU kg(-1) per infusion] was effective in preventing bleeding episodes, with a significantly lower (79%, P < 0.001) annualized bleed rate (4.2) compared to an on-demand treatment in a historical control group (20.0); 24 of 56 subjects on prophylaxis (43%) did not bleed throughout the study observation period. Of 249 total acute bleeds, 211 (84.7%) were controlled with one to two infusions of BAX326. Haemostatic efficacy at resolution of bleed was rated excellent or good in 96.0% of all treated bleeding episodes. The results of this study indicate that BAX326 is safe and efficacious in treating bleeds and routine prophylaxis in patients aged 12 years and older with haemophilia B.
    Haemophilia 07/2013; · 3.17 Impact Factor
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    ABSTRACT: Patients with haemophilia A and inhibitors are at high risk for severe bleeding, progression of joint disease and deterioration of health-related quality of life (HRQoL). To determine the impact of prophylaxis with an activated prothrombin complex concentrate (aPCC) on HRQoL, HRQoL was assessed using the Short-Form (SF)-36 Health Survey and the EQ-5D questionnaire in subjects ≥14 years participating in a prospective, randomized, crossover study comparing 6 months of aPCC prophylaxis with 6 months of on-demand therapy. Eighteen of 19 patients completed the survey or questionnaire before and after the on-demand therapy and prophylaxis periods. A general trend towards improved HRQoL after prophylaxis was observed for the 18 evaluable patients in all SF-36 dimensions except for vitality/energy and physical functioning. After prophylaxis, 'good responders,' defined as patients experiencing ≥50% reduction in bleeding, exhibited statistically and clinically significant differences in the physical component score (P = 0.021), role - physical (P = 0.042), bodily pain (P = 0.015), and social functioning (P = 0.036). Similarly, the EQ-5D health profile showed a trend towards improvement after prophylaxis in all evaluable patients. Among the good responders, improvements did not differ from those observed after on-demand treatment. EQ visual analogue scale values were slightly improved following prophylaxis for all evaluable patients and the EQ-5D utility index improved in the good responders only. During prophylaxis, patients missed significantly fewer days from school or work because of bleeding than during on-demand treatment (P = 0.01). In conclusion, by significantly reducing bleeding frequency in good responders, aPCC prophylaxis improved HRQoL compared with on-demand treatment.
    Haemophilia 06/2013; · 3.17 Impact Factor
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    ABSTRACT: The Upshaw Schulman syndrome (MIM #274150) is a hereditary deficiency of the von Willebrand factor cleaving protease (ADAMTS13) due to homozygous or compound heterozygous mutations in the ADAMTS13 gene. Patients are prone to bouts of thrombotic thrombocytopenic purpura. However, disease manifestation needs a second trigger event. Pregnancy is a known risk factor for TTP. Patients with USS may manifest during pregnancy and the postpartum period or relapse with a TTP bout. Before plasma therapy mortality for both the mother and the fetus was high, but even nowadays when plasma is delivered, therapy is challenging, still bearing a high risk for miscarriage or long term sequelae for the mother. In this report on pregnancies in three mothers with USS, plasma therapy was increased in frequency and amount given with regard to platelet count or ADAMTS13 activity, thus leading to a successful outcome.
    Hamostaseologie 05/2013; 33(2):144-148. · 1.59 Impact Factor
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    ABSTRACT: In this study we assessed homocysteine level in 106 patients with ET – 80 females and 26 males, mean age 54 (23–82) and in 20 healthy persons – 6 males and 14 females, mean age 41 (31–54). We also searched for a relation between homocysteine level and MTHFR gene mutation as well as vitamin B12 and folic acid concentration. Median homocysteine serum level was higher in ET patients than in control group. Elevated homocysteine level primarily stems from folic acid deficiency rather than from the presence of MTHFR gene mutation. Median folic acid level was lower in ET patients presenting thrombotic and bleeding complications than in ET patient without vascular episodes. We concluded that folic acid substitution may not only prevent hyperhomocysteinemia but also the development of vascular complications in ET patients.
    Acta haematologica Polonica 01/2013; 44(3):333–339.
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    ABSTRACT: Neutralizing antibodies against FVIII remain the major complication in the replacement therapy of hemophilia A patients. To better understand the evolution of these antibodies it is important to generate comprehensive data sets which include both neutralizing and non-neutralizing antibodies, their isotypes and IgG subclasses. We developed sensitive ELISA assays to analyze FVIII-binding antibodies in different cohorts of hemophilia A patients and in healthy individuals. Our data reveal the prevalence of FVIII-binding antibodies among healthy individuals (n=600) to be as high as 19%, with a prevalence of antibody titers ≥1:80 of 2%. The prevalence of FVIII-binding antibodies was 34% (5% for titers ≥1:80) in patients without FVIII inhibitors (n=77), 39% (4% for titers ≥1:80) in patients after successful ITI (n=23) and 100% (n=20, all titers ≥1:80) in patients with FVIII inhibitors. We found significant differences for IgG subclasses of FVIII-binding antibodies between the different study cohorts. IgG4 and IgG1 were the most abundant IgG subclasses in patients with FVIII inhibitors. Strikingly, IgG4 was completely absent in patients without FVIII inhibitors and in healthy subjects. These findings point towards a distinct immune regulatory pathway responsible for the development of FVIII-specific IgG4 associated with FVIII inhibitors.
    Blood 12/2012; · 9.78 Impact Factor
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    ABSTRACT: The benefits of prophylaxis of haemophilia A patients regarding joint health and quality-of-life are well established. However, adherence to an up to every-other-day infusion regimen is a barrier to widespread adoption of prophylaxis. BAY 79-4980 is an investigational drug consisting of rFVIII-FS (sucrose-formulated recombinant FVIII) reconstituted with liposome solvent. Previous clinical studies showed extended protection from bleeding after a single injection of BAY 79-4980 (13.3 ± 6.2 days) compared with rFVIII-FS (7.2 ± 1.7 days). The effect of once-a-week prophylaxis with BAY 79-4980 (35 IU/kg) compared with three times-per-week rFVIII-FS (25 IU/kg) in previously treated, severe haemophilia A patients was evaluated in a 52-week, double-blind, two-arm, randomised, controlled study. The primary and secondary endpoints were protection from total bleeds and joint bleeds, respectively. Short- and long-term safety and tolerability of BAY 79-4980 including effects on lipid levels were assessed. A total of 139 and 131 subjects were evaluable for safety and efficacy analyses, respectively. A large difference in efficacy between treatment groups was observed with 72.1% (49/68) in the rFVIII-FS control group demonstrating <9 bleeds/year compared with 38.1% (24/63) of BAY 79-4980-treated subjects. A similar difference was seen in annualised joint bleeds, with 43 subjects (63.2%) in the control group demonstrating <5 joint bleeds/year compared with 24 subjects (38.1%) treated with BAY 79-4980. The distribution of bleeds seven days post-prophylactic treatment with BAY 79-4980 showed that 61% of bleeds occurred after day 4 post dosing. There were no safety concerns identified. The investigational treatment arm was prematurely discontinued due to failure to achieve the primary endpoint.
    Thrombosis and Haemostasis 09/2012; 108(5). · 5.76 Impact Factor
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    ABSTRACT: von Willebrand's disease (VWD) is probably the most common bleeding disorder, with some studies indicating that up to 1% of the population may have the condition. Over recent years interest in VWD has fallen compared to that of haemophilia, partly the result of focus on blood-borne diseases such as HIV and hepatitis. Now the time has come to revisit VWD, and in view of this some 60 international physicians with clinical and scientific interest in VWD met over 4 days in 2010 in the Åland islands to discuss state-of-the-art issues in the disease. The Åland islands are where Erik von Willebrand had first observed a bleeding disorder in a number of members of a family from Föglö, and 2010 was also the 140th anniversary of his birth. This report summarizes the main papers presented at the symposium; topics ranged from genetics and biochemistry through to classification of VWD, pharmacokinetics and laboratory assays used in the diagnosis of the disease, inhibitors, treatment guidelines in different age groups including the elderly who often have comorbid conditions that present challenges, and prophylaxis. Other topics included managing surgeries in patients with VWD and the role of FVIII in VWF replacement, a controversial subject.
    Haemophilia 09/2012; 18 Suppl 6:1-13. · 3.17 Impact Factor
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    ABSTRACT: Inherited factor VII (FVII) deficiency is a rare coagulation disorder with variable haemorrhagic manifestations. In severely affected cases spontaneous haemarthroses leading to advanced arthropathy have been observed. Such cases may require surgery. Therapeutic options for bleeding prevention in FVII deficient patients undergoing surgery comprise various FVII preparations but the use of recombinant activated factor VII (rFVIIa) seems to be the treatment of choice. To present the outcome of orthopaedic surgery under haemostatic coverage of rFVIIa administered according to the locally established treatment regimen in five adult patients with FVII baseline plasma levels below 10 IU dL(-1) . Two patients required total hip replacement (THR); three had various arthroscopic procedures. Recombinant activated factor VII was administered every 8 h on day of surgery (D0) followed by every 12-24 h for the subsequent 9-14 days, depending on the type of surgery. Factor VII plasma coagulation activity (FVII:C) was determined daily with no predefined therapeutic target levels. Doses of rFVIIa on D0 ranged from 18 to 37 μg kg(-1) b.w. and on the subsequent days - from 13 to 30 μg kg(-1) b.w. Total rFVIIa dose per procedure ranged from 16 to 37.5 mg, and the total number of doses per procedure was 16-31. None of our patients developed excessive bleeding including those in whom FVII:C trough levels returned nearly to the baseline level on the first post-op day. Preliminary results demonstrate that rFVIIa administered according to our treatment regimen is an effective and safe haemostatic agent for hypoproconvertinaemia patients undergoing orthopaedic surgery.
    Haemophilia 07/2012; · 3.17 Impact Factor
  • Haemophilia 04/2012; 18(4):e352-4. · 3.17 Impact Factor
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    ABSTRACT: BAY 86-6150 is a new human recombinant factor VIIa variant developed for high procoagulant activity and longer action in people with hemophilia with inhibitors. To investigate the safety, tolerability, pharmacodynamics, pharmacokinetics and immunogenicity of BAY 86-6150 in non-bleeding hemophilia subjects. The study included non-bleeding men (18-65 years of age) with moderate or severe hemophilia A or B with or without inhibitors. Sixteen subjects were randomized 3 : 1 to four cohorts of escalating doses of BAY 86-6150 (6.5, 20, 50 or 90 μg kg(-1) [n = 3 per cohort]) or placebo (n = 1 per cohort); an independent data-monitoring committee reviewed previous cohort data before the next dose escalation. Blood sampling was performed predose and postdose; subjects were monitored for 50 days postdose. At the tested doses, BAY 86-6150 was not associated with clinically significant adverse events or dose-limiting toxicities. BAY 86-6150 pharmacokinetics exhibited a linear dose response, with a half-life of 5-7 h. Subjects demonstrated consistent, dose-dependent thrombin generation ex vivo in platelet-poor plasma (PPP) (mean peak effect, 26-237 nm thrombin from 6.5 to 90 μg kg(-1)). Peak thrombin levels over time paralleled BAY 86-6150, with thrombin kinetics appearing to be slightly shorter; thus, circulating BAY 86-6150 retained activity. There were corresponding decreases in activated partial thromboplastin and prothrombin times. No subject developed de novo anti-BAY 86-6150 neutralizing antibodies during the 50-day follow-up. In this first-in-human, multicenter, randomized, double-blind, placebo-controlled, single-dose escalation study, BAY 86-6150 was tolerated at the highest dose (90 μg kg(-1)), with no safety concerns. Safety and efficacy will be further evaluated in phase II/III studies.
    Journal of Thrombosis and Haemostasis 02/2012; 10(5):773-80. · 6.08 Impact Factor
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    ABSTRACT: A recombinant factor VIIa analog (NN1731; vatreptacog alfa [activated]) was developed to provide safe, rapid and sustained resolution of bleeds in patients with hemophilia and inhibitors. This global, prospective, randomized, double-blinded, active-controlled, dose-escalation trial evaluated and compared one to three doses of vatreptacog alfa at 5, 10, 20, 40, and 80 lg kg(-1) with one to three doses of recombinant FVIIa (rFVIIa) at 90 lg kg(-1) in the treatment of acute joint bleeds in hemophilia patients with inhibitors. The primary endpoint comprised adverse events; secondary endpoints were evaluations of immunogenicity, pharmacokinetics, and efficacy. Overall, 96 joint bleeds in 51 patients (> 12 years of age) were dosed. Vatreptacog alfa was well tolerated, with a low frequency of adverse events. No immunogenic or thrombotic events related to vatreptacog alfa were reported. A high efficacy rate of vatreptacog alfa in controlling acute joint bleeds was observed; 98% of bleeds were controlled within 9 h of the initial dose in a combined evaluation of 20–80 lg kg(-1) vatreptacog alfa. The efficacy rate observed for rFVIIa (90%) is consistent with data from published clinical trials. The trial was not powered to compare efficacy, and further trials are needed to investigate the efficacy of vatreptacog alfa as compared with that of rFVIIa. The trial was registered at ClinicalTrials.gov (Registration Number: NCT00486278).
    Journal of Thrombosis and Haemostasis 01/2012; 10(1):81-9. · 6.08 Impact Factor

Publication Stats

300 Citations
216.24 Total Impact Points

Institutions

  • 2006–2014
    • Institute of Hematology and Blood Transfusion, Warsaw
      Warszawa, Masovian Voivodeship, Poland
    • American Thrombosis and Hemostasis Network
      Chicago, Illinois, United States
  • 2002–2014
    • Instytut Hematologii i Transfuzjologii
      Warszawa, Masovian Voivodeship, Poland
  • 2013
    • Friedrich-Schiller-University Jena
      Jena, Thuringia, Germany
  • 2011
    • Jagiellonian University
      • Department of Hematology
      Kraków, Lesser Poland Voivodeship, Poland
  • 2006–2009
    • Malmö University
      Malmö, Skåne, Sweden