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Tardy B, Lambert T, Chamouni P, Montmartin A, Trossaert M, Claeyssens S, Berger C, Ardillon L, Gay V, Delavenne X, Harroche A, Chelle P. Revised terminal half-life of nonacog alfa as derived from extended sampling data: A real-world study involving 64 haemophilia B patients on nonacog alfa regular prophylaxis. Haemophilia 2022; 28:542-547. [PMID: 35420242 DOI: 10.1111/hae.14560] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2021] [Revised: 03/16/2022] [Accepted: 03/22/2022] [Indexed: 01/20/2023]
Abstract
BACKGROUND Nonacog alfa, a standard half-life recombinant factor IX (FIX), is used as a prophylactic treatment in severe haemophilia B (SHB) patients. Its half-life determined in clinical studies involving a limited sampling (72 h) was shown to be rather short. In our clinical practice, we suspected that its half-life could have been underestimated. OBJECTIVES We aimed to evaluate nonacog alfa pharmacokinetics in real world clinical practice based on FIX levels in patients receiving prophylaxis. METHODS We retrospectively collected data on patients with SHB receiving prophylaxis from eight centres across France. The terminal half-life (THL), time to reach 5-2 IU/dl and FIX activity at 48, 72 and 96 h were derived by Bayesian estimations using NONMEM analysis. RESULTS AND CONCLUSIONS Infusion data (n = 455) were collected from 64 patients with SHB. The median THL measured in 92 pharmacokinetic (PK) studies was 43.4 h. In 26 patients ≤12 years of age, 51 PK studies showed a median time to reach 5 IU/dl of FIX of 70.5 h and a median time to reach 2 IU/dl of 121.5 h. In 38 patients 13-75 years of age, 41 PK studies showed a median time to reach 5 IU/dl of FIX of 92.0 h and a median time to reach 2 IU/dl of 167.5 h. Extending the sampling beyond 72 h makes it possible to observe a plateau, with FIX remaining between 2 and 5 IU/dl for several days and shows that the THL of nonacog alfa might be longer than previously described. ESSENTIALS Nonacog alfa terminal half-life (THL) in patients receiving regular prophylaxis was evaluated in clinical practice. The median THL was estimated to be 36.9 h for patients aged .8-12 years. The median THL was estimated to be 49.9 h for patients aged 13-75 years. For patients aged ≤12 and >12 years, the median times to reach 5 IU/dl were 70.5 and 92 h, respectively; to reach 3 IU/dl, 95.5 and 131.5 h, respectively; to reach 2 IU/dl, 121.5 and 167.5 h, respectively. We suggest that the half-life of nonacog alfa might be longer than previously described in both younger and older patients.
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Affiliation(s)
- Brigitte Tardy
- Centre de Ressources et de Compétence Maladies hémorragiques, CHU Saint-Etienne, Hôpital Nord, Saint-Etienne, France.,Sainbiose, Inserm, U1059, Université Lyon, Saint-Etienne, France.,Inserm, CIC 1408, CHU Saint-Etienne Hôpital Nord, Saint-Etienne, France
| | - Thierry Lambert
- Centre de Référence Maladies hémorragiques CHU Paris Sud-Hôpital de Bicêtre, Le Kremlin-Bicêtre, France
| | - Pierre Chamouni
- Laboratoire d'Hématologie, Institut de Biologie Clinique, CHU de Rouen, Rouen, France
| | | | - Marc Trossaert
- Centre de Ressources et de Compétence Maladies hémorragiques, CHU de Nantes, Nantes, France
| | - Ségolène Claeyssens
- Centre de Ressources et de Compétence Maladies hémorragiques, CHU Toulouse-Hôpital Purpan, Toulouse, France
| | - Claire Berger
- Centre de Ressources et de Compétence Maladies hémorragiques, CHU Saint-Etienne, Hôpital Nord, Saint-Etienne, France
| | - Laurent Ardillon
- Centre de Ressources et de Compétence Maladies hémorragiques, CHU Tours-Hôpital Trousseau, Tours, France
| | - Valérie Gay
- Centre de Ressources et de Compétence Maladies hémorragiques, Centre hospitalier Métropole Savoie, Chambéry, France
| | - Xavier Delavenne
- Sainbiose, Inserm, U1059, Université Lyon, Saint-Etienne, France
| | - Annie Harroche
- Centre de Référence Maladies hémorragiques, Hôpital Necker Enfants-Malades, Université Paris Descartes, Paris, France
| | - Pierre Chelle
- School of Pharmacy, University of Waterloo, Waterloo, Canada
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2
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Tang F, Wong H, Ng CM. Rational Clinical Dose Selection of Adeno-Associated Virus-Mediated Gene Therapy Based on Allometric Principles. Clin Pharmacol Ther 2021; 110:803-807. [PMID: 33884615 DOI: 10.1002/cpt.2269] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Accepted: 04/06/2021] [Indexed: 12/17/2022]
Abstract
One of the challenges in translational medicine is to select first-in-human doses of investigational drugs based on findings in preclinical studies. Despite substantial progress in the optimization of recombinant adeno-associated virus (AAV) vectors of in vivo gene therapy for treating various diseases, there remain significant limitations to the use of preclinical data to guide dose selection in clinical trials. Here we introduce a novel concept of gene efficiency factor (GEF) to describe the efficiency of the gene transfer system and describe and apply the concept of GEF in AAV-mediated in vivo gene transfer systems. We explore the utility of allometric scaling to translate GEF across species using AAV-mediated in vivo factor IX (FIX) gene therapy for hemophilia B and to demonstrate the use of GEF in predicting efficacious AAV vector doses in humans. We show for the first time that an allometric relationship exists for GEF of AAV-mediated in vivo gene therapy. Furthermore, we demonstrate the feasibility of using the allometric relationship of GEF to select efficacious first-in-human doses of virus-mediated invivo gene therapy. Based on our findings, allometry of GEF can be used to translate biological efficiency from animal studies to clinical studies and provide a rational basis of setting first-in-human doses for new virus-mediated invivo gene therapy products.
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Affiliation(s)
- Fei Tang
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, Kentucky, USA
| | - Harvey Wong
- Faculty of Pharmaceutical Sciences, College of Pharmacy, University of British Columbia, Vancouver, British Columbia, Canada
| | - Chee M Ng
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, Kentucky, USA.,NewGround Pharmaceutical Consulting LLC, Foster City, California, USA
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3
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Yu JK, Iorio A, Edginton AN. Using pharmacokinetics for tailoring prophylaxis in people with hemophilia switching between clotting factor products: A scoping review. Res Pract Thromb Haemost 2019; 3:528-541. [PMID: 31294337 PMCID: PMC6611373 DOI: 10.1002/rth2.12204] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Revised: 02/28/2019] [Accepted: 03/21/2019] [Indexed: 01/19/2023] Open
Abstract
The objective of this scoping review is to summarize the current use of pharmacokinetics for tailoring prophylaxis in hemophilia patients switching between clotting factor products. Patients with hemophilia may require switching of clotting factor concentrates due to a variety of factors, but there have been perceived risks associated with switching, such as inhibitor development or suboptimal protection due to inadequate dosing while titrating treatment. Studies that look at patients switching from one clotting factor concentrate to another are categorized in terms of their primary and/or secondary objectives, notably biosimilarity and comparative pharmacokinetic studies and inhibitor development studies. Research on how best to switch concentrates with respect to dosing regimen are lacking, and currently a trial‐and‐error approach is used for dosing the new factor concentrate. In the future, studies looking at the predictability of pharmacokinetics (PK) of a new factor concentrate based on individual PK knowledge of the original factor concentrate may offer clinical benefit by providing a safer switching approach and protocol.
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Affiliation(s)
- Jacky K Yu
- School of Pharmacy University of Waterloo Waterloo Ontario Canada
| | - Alfonso Iorio
- Department of Health Research Methods, Evidence, and Impact McMaster University Hamilton Ontario Canada.,McMaster-Bayer Research Chair in Clinical Epidemiology of Congenital Bleeding Disorders Department of Medicine McMaster University Hamilton Ontario Canada
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4
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Escuriola Ettingshausen C, Hegemann I, Simpson ML, Cuker A, Kulkarni R, Pruthi RK, Garly M, Meldgaard RM, Persson P, Klamroth R. Favorable pharmacokinetics in hemophilia B for nonacog beta pegol versus recombinant factor IX-Fc fusion protein: A randomized trial. Res Pract Thromb Haemost 2019; 3:268-276. [PMID: 31011711 PMCID: PMC6462750 DOI: 10.1002/rth2.12192] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2018] [Accepted: 02/09/2019] [Indexed: 01/19/2023] Open
Abstract
BACKGROUND AND OBJECTIVE Nonacog beta pegol (N9-GP) and recombinant factor IX-Fc fusion protein (rFIXFc) are extended half-life rFIX compounds. We report the first single-dose pharmacokinetic trial of N9-GP and rFIXFc. PATIENTS/METHODS Paradigm 7 was a multicenter, open-label, randomized, crossover trial in previously treated (>150 exposure days) adults with congenital hemophilia B (FIX activity ≤2%). Patients received single intravenous injections (50 IU/kg) of N9-GP and rFIXFc with at least 21 days between doses. Plasma FIX activity, predose, and at serial time points up to 240 hours postdose, was measured using validated one-stage clotting assays (SynthAFax for N9-GP; Actin FSL for rFIXFc) and a chromogenic assay (ROX factor IX) with normal human plasma as calibrator. The primary endpoint was area under the FIX activity-time curve from 0 to infinity, dose-normalized to 50 IU/kg (AUC0-inf,norm). RESULTS Fifteen patients received study treatment. Based on FIX activity results from the one-stage clotting assays, estimated AUC0-inf,norm was significantly greater for N9-GP than rFIXFc (ratio: 4.39; P < 0.0001, based on a two-sided test on 5% significance level). In addition, N9-GP had a longer terminal half-life, two times higher incremental recovery at 30 minutes and maximum FIX activity (dose-normalized to 50 IU/kg) and six times higher FIX activity at 168 hours than rFIXFc. These findings were largely comparable with the chromogenic assay data and are consistent with published data for each compound. CONCLUSIONS In this comparison, N9-GP demonstrated favorable pharmacokinetic characteristics versus rFIXFc, helping clinicians to understand differences between N9-GP and rFIXFc. REGISTRATION This trial is registered with clinicaltrials.gov (NCT03075670) and the European Clinical Trials Database (EudraCT: 2016-001149-25).
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Affiliation(s)
| | - Inga Hegemann
- Division of HaematologyZürich University HospitalZürichSwitzerland
| | - Mindy L. Simpson
- Pediatric Hematology/OncologyRush University Medical CenterChicagoILUSA
| | - Adam Cuker
- Perelman School of MedicineUniversity of PennsylvaniaPhiladelphiaPAUSA
| | - Roshni Kulkarni
- Department of Pediatrics and Human DevelopmentMichigan State UniversityEast LansingMIUSA
| | | | | | | | | | - Robert Klamroth
- Department for Internal MedicineVascular Medicine and HaemostaseologyVivantes KlinikumBerlinGermany
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5
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Morfini M, Gherardini S. Pharmacokinetic-based prediction of real-life dosing of extended half-life clotting factor concentrates on hemophilia. Ther Adv Hematol 2018; 9:149-162. [PMID: 29899890 PMCID: PMC5992810 DOI: 10.1177/2040620718774258] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2017] [Accepted: 04/09/2018] [Indexed: 01/12/2023] Open
Abstract
The improvement of clotting factor concentrates (CFCs) has undergone an impressive boost during the last six years. Since 2010, several new recombinant factor (rF)VIII/IX concentrates entered phase I/II/III clinical trials. The improvements are related to the culture of human embryonic kidney (HEK) cells, post-translational glycosylation, PEGylation, and co-expression of the fragment crystallizable (Fc) region of immunoglobulin (Ig)G1 or albumin genes in the manufacturing procedures. The extended half-life (EHL) CFCs allow an increase of the interval between bolus administrations during prophylaxis, a very important advantage for patients with difficulties in venous access. Although the inhibitor risk has not been fully established, phase III studies have provided standard prophylaxis protocols, which, compared with on-demand treatment, have achieved very low annualized bleeding rates (ABRs). The key pharmacokinetics (PK) parameter to tailor patient therapy is clearance, which is more reliable than the half-life of CFCs; the clearance considers the decay rate of the drug concentration-time profile, while the half-life considers only the half concentration of the drug at a given time. To tailor the prophylaxis of hemophilia patients in real-life, we propose two formulae (expressed in terms of the clearance, trough and dose interval between prophylaxis), respectively based on the one- and two-compartmental models (CMs), for the prediction of the optimal single dose of EHL CFCs. Once the data from the time decay of the CFCs are fitted by the one- or two-CMs after an individual PK analysis, such formulae provide to the treater the optimal trade-off among trough and time-intervals between boluses. In this way, a sufficiently long time-interval between bolus administration could be guaranteed for a wider class of patients, with a preassigned level of the trough. Finally, a PK approach using repeated dosing is discussed, and some examples with new EHL CFCs are shown.
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Affiliation(s)
| | - Stefano Gherardini
- Department of Physics and Astronomy, LENS, and
QSTAR, University of Florence, Sesto Fiorentino (Italy)
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6
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Tiede A, Abdul-Karim F, Carcao M, Persson P, Clausen WHO, Kearney S, Matsushita T, Negrier C, Oldenburg J, Santagostino E, Young G. Pharmacokinetics of a novel extended half-life glycoPEGylated factor IX, nonacog beta pegol (N9-GP) in previously treated patients with haemophilia B: results from two phase 3 clinical trials. Haemophilia 2017; 23:547-555. [DOI: 10.1111/hae.13191] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/23/2016] [Indexed: 11/28/2022]
Affiliation(s)
- A. Tiede
- Clinic for Haematology, Haemostaseology, Oncology and Stem Cell Transplantation; Hannover Medical School; Hannover Germany
| | - F. Abdul-Karim
- Hemophilia Clinic; National Blood Centre; Wilayah Persekutuan Kuala Lumpur Malaysia
| | - M. Carcao
- Division of Haematology/Oncology; Department of Paediatrics; Child Health Evaluative Sciences; Research Institute; The Hospital for Sick Children; University of Toronto; Toronto ON Canada
| | | | | | - S. Kearney
- CHCMN Hemophilia and Thrombosis Center; Children's Hospital and Clinics of Minnesota; MN USA
| | - T. Matsushita
- Department of Transfusion Medicine; Nagoya University Hospital; Nagoya Japan
| | - C. Negrier
- Centre Regional de Traitement de l'Hemophilie; Hopital Louis Pradel; University Claude Bernard; Lyon France
| | - J. Oldenburg
- Institute of Experimental Haematology and Transfusion Medicine; Bonn Germany
| | - E. Santagostino
- Angelo Bianchi Bonomi Haemophilia and Thrombosis Centre; Maggiore Hospital; IRCCS Ca Granda Foundation; Milan Italy
| | - G. Young
- Hemostasis and Thrombosis Center; Children's Hospital Los Angeles; Keck School of Medicine; University of Southern California; Los Angeles CA USA
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7
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Fischer K, Kulkarni R, Nolan B, Mahlangu J, Rangarajan S, Gambino G, Diao L, Ramirez-Santiago A, Pierce GF, Allen G. Recombinant factor IX Fc fusion protein in children with haemophilia B (Kids B-LONG): results from a multicentre, non-randomised phase 3 study. LANCET HAEMATOLOGY 2017; 4:e75-e82. [DOI: 10.1016/s2352-3026(16)30193-4] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2016] [Revised: 11/21/2016] [Accepted: 11/22/2016] [Indexed: 11/27/2022]
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8
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Suzuki A, Tomono Y, Korth-Bradley JM. Population pharmacokinetic modelling of factor IX activity after administration of recombinant factor IX in patients with haemophilia B. Haemophilia 2016; 22:e359-66. [DOI: 10.1111/hae.12969] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/11/2016] [Indexed: 11/28/2022]
Affiliation(s)
- A. Suzuki
- Department of Clinical Pharmacology; Pfizer Inc; Tokyo Japan
| | - Y. Tomono
- Department of Clinical Pharmacology; Pfizer Inc; Tokyo Japan
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9
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Pharmacokinetics, Efficacy, and Safety of Nonacog Alfa in Previously Treated Patients with Moderately Severe to Severe Hemophilia B. Clin Ther 2016; 38:936-44. [DOI: 10.1016/j.clinthera.2016.02.015] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2015] [Revised: 02/03/2016] [Accepted: 02/13/2016] [Indexed: 11/17/2022]
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10
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Morfini M, Dragani A, Paladino E, Radossi P, Di Minno G, Mazzucconi MG, Rossetti G, Barillari G, Napolitano M, Tagariello G. Correlation between FIX genotype and pharmacokinetics of Nonacog alpha according to a multicentre Italian study. Haemophilia 2016; 22:537-42. [DOI: 10.1111/hae.12916] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/05/2016] [Indexed: 01/03/2023]
Affiliation(s)
- M. Morfini
- Past President of Italian Association of Haemophilia Centres (AICE); Firenze Italy
| | - A. Dragani
- Haemophilia & Thrombosis Centre; Haematology Department; Regional Hospital; Pescara Italy
| | - E. Paladino
- Atherothrombotic Diseases; Cardio-Vascular Department; University Hospital of Florence; Florence Italy
| | - P. Radossi
- Haematology and Haemophilia Centre; Regional Hospital; Castelfranco Veneto Italy
| | - G. Di Minno
- Reference Centre for Haemophilia and Thrombosis; Department of Clinical and Experimental Medicine; Federico II University; Naples Italy
| | - M. G. Mazzucconi
- Haemophilia & Thrombosis Centre; Haematology Department; La Sapienza University; Rome Italy
| | - G. Rossetti
- Haemophilia Centre; Santa Chiara Hospital; Trento Italy
| | - G. Barillari
- Haemophilia Centre; S. Maria della Misericordia Hospital; Udine Italy
| | - M. Napolitano
- Haemophilia & Thrombosis Centre; Haematology Department; University of Palermo; Palermo Italy
| | - G. Tagariello
- Haematology and Haemophilia Centre; Regional Hospital; Castelfranco Veneto Italy
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11
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Heparin supplement counteracts the prohemostatic effect of prothrombin complex concentrate and factor IX concentrate: An in vitro evaluation. Thromb Res 2016; 139:102-10. [PMID: 26916304 DOI: 10.1016/j.thromres.2016.01.017] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2015] [Revised: 01/20/2016] [Accepted: 01/24/2016] [Indexed: 11/23/2022]
Abstract
INTRODUCTION Coagulation factor concentrates like factor IX (FIX) and prothrombin complex concentrate (PCC) can contain anticoagulant substances that may hamper their procoagulant effectiveness in the treatment of hemophilia B or reversal of oral anticoagulation, as well as the laboratory assessment thereof. The aim of the present study was to evaluate the influence of anticoagulant heparin supplement on the prohemostatic potential of different PCCs and FIX concentrates. MATERIALS AND METHODS Prohemostatic potential was evaluated in vitro employing PT/aPTT, thrombography (TGA) and thromboelastography (TEG) with FIX deficient plasma, vitamin K antagonist (VKA)-anticoagulated plasma and plasma anticoagulated with rivaroxaban. RESULTS Most PCCs contained heparin, while heparin was detected in 1 out of 4 examined FIX concentrates. All heparin-containing clotting factor concentrates showed severely hampered prohemostatic effects when therapeutic doses were added to anticoagulated plasmas. Upon heparin removal, comparable prohemostatic effects were observed. Of importance is the notion that the anticoagulant effect of heparin was enhanced by rivaroxaban, resulting in a 7 fold increased PT sensitivity towards heparin in the presence of 500μg/L rivaroxaban. CONCLUSIONS Compositional differences between clotting factor concentrates should be taken into account. Therapeutic levels of heparin may be co-infused when treating emergency bleeds with high prohemostatic drug doses, particularly those recommended in the reversal of non-VKA anticoagulants such as rivaroxaban by PCC. Given the relative short half-life of heparin compared to vitamin K-dependent clotting factors, an anticoagulant heparin effect shortly after concentrate infusion should be considered clinically and while interpreting laboratory coagulation parameters.
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12
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Monroe DM, Jenny RJ, Van Cott KE, Buhay S, Saward LL. Characterization of IXINITY® (Trenonacog Alfa), a Recombinant Factor IX with Primary Sequence Corresponding to the Threonine-148 Polymorph. Adv Hematol 2016; 2016:7678901. [PMID: 26997955 PMCID: PMC4779506 DOI: 10.1155/2016/7678901] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2015] [Accepted: 01/14/2016] [Indexed: 11/17/2022] Open
Abstract
The goal of these studies was to extensively characterize the first recombinant FIX therapeutic corresponding to the threonine-148 (Thr-148) polymorph, IXINITY (trenonacog alfa [coagulation factor IX (recombinant)]). Gel electrophoresis, circular dichroism, and gel filtration were used to determine purity and confirm structure. Chromatographic and mass spectrometry techniques were used to identify and quantify posttranslational modifications. Activity was assessed as the ability to activate factor X (FX) both with and without factor VIIIa (FVIIIa) and in a standard clotting assay. All results were consistent across multiple lots. Trenonacog alfa migrated as a single band on Coomassie-stained gels; activity assays were normal and showed <0.002 IU of activated factor IX (FIXa) per IU of FIX. The molecule has >97% γ-carboxylation and underwent the appropriate structural change upon binding calcium ions. Trenonacog alfa was activated normally with factor XIa (FXIa); once activated it bound to FVIIIa and FXa. When activated to FIXa, it was inhibited efficiently by antithrombin. Glycosylation patterns were similar to plasma-derived FIX with sialic acid content consistent with the literature reports of good pharmacokinetic performance. These studies have shown that trenonacog alfa is a highly pure product with a primary sequence and posttranslational modifications consistent with the common Thr-148 polymorphism of plasma-derived FIX.
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Affiliation(s)
- Dougald M. Monroe
- School of Medicine, Department of Hematology/Oncology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Richard J. Jenny
- Haematologic Technologies, Incorporated, Essex Junction, VT 05452, USA
| | - Kevin E. Van Cott
- Department of Chemical and Biomolecular Engineering, University of Nebraska-Lincoln, Lincoln, NE 68588, USA
| | - Shelly Buhay
- Biosciences Division, Emergent BioSolutions Incorporated, Winnipeg, MB, Canada R3T 5Y3
| | - Laura L. Saward
- Biosciences Division, Emergent BioSolutions Incorporated, Winnipeg, MB, Canada R3T 5Y3
- University of Manitoba, Winnipeg, MB, Canada R3T 2N2
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13
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Enjolras N, Perot E, Le Quellec S, Indalecio A, Girard J, Negrier C, Dargaud Y. In vivo efficacy of human recombinant factor IX produced by the human hepatoma cell line HuH-7. Haemophilia 2015; 21:e317-21. [PMID: 25981983 DOI: 10.1111/hae.12688] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/12/2015] [Indexed: 11/28/2022]
Abstract
INTRODUCTION Post-translational modifications of the CHO-cell-derived-recombinant human factor IX (FIX) currently used for the treatment of hemophilia B (HB) are different from plasma derived FIX. Our previous studies described a rFIX (HIX) having better profile of post-translational modifications than rFIX produced by CHO cells. The aim of the study consisted to verify the improved post-translational modifications effect of HIX on in vivo recovery. MATERIALS AND METHODS HIX has been produced in a bioreactor and then purified from supernatants. In vitro activation and activity were evaluated measured by thrombin generation tests (TGT) and compared to commercial molecules, Benefix(®) , Mononine(®) . The three molecules were then administrated (i.v.) to FIX-knockout mice and two minutes after injection, blood samples were collected and subjected to human FIX-specific-ELISA and TGT. RESULTS The clotting function of HIX, activation courses of HIX by FXIa and FVIIa-TF complex appear normal as did activation of Benefix(®) , Mononine(®) and TG constants of each FIX were equivalent. After injection to HB mice, circulating HIX did not present any significant difference in term of antigen value with Benefix(®) . Intriguingly, TGT were clearly exhibiting a better velocity for HIX than Benefix(®) and Mononine(®) . These data suggested that HIX may improve in vivo coagulant efficacy in comparison with the two commercial FIX injected at the same dose. CONCLUSION The study shows that HuH-7-derived-rFIX has better in vivo haemostatic activity in hemophilia B mice compared to the reference rFIX molecule despite similar in vivo recovery rates, suggesting that HuH-7 cells could represent an effective cellular system for production of rFIX.
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Affiliation(s)
- N Enjolras
- Unite Hemostase, Inflammation and Sepsis EA 4174, Faculte de Medecine Laennec, Universite Lyon 1-Hospices Civils de Lyon, Lyon, France
| | - E Perot
- Unite Hemostase, Inflammation and Sepsis EA 4174, Faculte de Medecine Laennec, Universite Lyon 1-Hospices Civils de Lyon, Lyon, France
| | - S Le Quellec
- Unite Hemostase, Inflammation and Sepsis EA 4174, Faculte de Medecine Laennec, Universite Lyon 1-Hospices Civils de Lyon, Lyon, France
| | - A Indalecio
- Unite Hemostase, Inflammation and Sepsis EA 4174, Faculte de Medecine Laennec, Universite Lyon 1-Hospices Civils de Lyon, Lyon, France
| | - J Girard
- Unite Hemostase, Inflammation and Sepsis EA 4174, Faculte de Medecine Laennec, Universite Lyon 1-Hospices Civils de Lyon, Lyon, France
| | - C Negrier
- Unite Hemostase, Inflammation and Sepsis EA 4174, Faculte de Medecine Laennec, Universite Lyon 1-Hospices Civils de Lyon, Lyon, France
| | - Y Dargaud
- Unite Hemostase, Inflammation and Sepsis EA 4174, Faculte de Medecine Laennec, Universite Lyon 1-Hospices Civils de Lyon, Lyon, France
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14
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Suzuki N, Takedani H, Hirakawa A, Ushijima Y, Matsushita T. The features of clearance in recombinant factor IX (BeneFIX(®) ). Haemophilia 2015; 21:702-7. [PMID: 25854709 DOI: 10.1111/hae.12672] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/13/2015] [Indexed: 11/28/2022]
Abstract
INTRODUCTION Dosage adjustment is very important to perform continuous infusion (CI) of recombinant factor IX (rFIX) concentrates more effectively and economically, and clearance (CL) is strongly related to the infusion rate. However, previous reports have shown that the CL of rFIX concentrates varies widely (4.2-11.4 mL kg(-1) h(-1) ). AIM The goal of this study was to gain a better understanding of the CL of the rFIX concentrate (BeneFIX(®) ) to precisely set the infusion rate of rFIX concentrates. METHODS We estimated CLs by five different calculation approaches: from area under the blood concentration-time curve (AUC), from in vivo recovery (IVR) and half-life, from actual FIX activity value during CI, and from the simulation by one-compartment model in seven patients with haemophilia B. RESULTS The mean CL calculated from AUC was 3.8 ± 0.4 mL kg(-1) h(-1) (range = 3.3-4.3 mL kg(-1) h(-1) ). CONCLUSION The mean CL calculated from IVR and distribution half-life was 4.4 ± 0.4 mL kg(-1) h(-1) (range = 4.0-5.1 mL kg(-1) h(-1) ). The mean CL calculated from IVR and terminal half-life was 2.1 ± 0.5 mL kg(-1) h(-1) (range = 1.7-2.8 mL kg(-1) h(-1) ). The mean CL during CI was 4.9 ± 0.6 mL kg(-1) h(-1) (range = 4.2-5.6 mL kg(-1) h(-1) ). In addition, when we simulated the theoretical CL using a one-compartment model, the adjusted mean CL during CI was 4.8 ± 0.5 mL kg(-1) h(-1) (range = 4.0-5.4 mL kg(-1) h(-1) ). The CL obtained from distribution half-life was comparable to the CL during CI, while the CL calculated from terminal half-life did not reflect actual CL. Further, the rFIX concentrate was characterized by a one-compartment model under certain conditions.
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Affiliation(s)
- N Suzuki
- Department of Clinical Laboratory Medicine, Nagoya University Hospital, Nagoya, Japan
| | - H Takedani
- Department of Joint Surgery, Institute of Medical Science, University of Tokyo Research Hospital, Tokyo, Japan
| | - A Hirakawa
- Biostatistics Section, Center for Advanced Medicine and Clinical Research, Nagoya University Hospital, Nagoya, Japan
| | - Y Ushijima
- Department of Hematology and Oncology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - T Matsushita
- Department of Transfusion Medicine, Nagoya University Hospital, Nagoya, Japan
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15
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Metzger JM, Tadin-Strapps M, Thankappan A, Strapps WR, DiPietro M, Leander K, Zhang Z, Shin MK, Levorse J, Desai K, Xu Y, Lai K, Wu W, Chen Z, Cai TQ, Jochnowitz N, Bentley R, Hoos L, Zhou Y, Sepp-Lorenzino L, Seiffert D, Andre P. Titrating haemophilia B phenotypes using siRNA strategy: evidence that antithrombotic activity is separated from bleeding liability. Thromb Haemost 2015; 113:1300-11. [PMID: 25790442 DOI: 10.1160/th14-06-0505] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2014] [Accepted: 01/20/2015] [Indexed: 11/05/2022]
Abstract
Haemophilia A and B are characterised by a life-long bleeding predisposition, and several lines of evidence suggest that risks of atherothrombotic events may also be reduced. Establishing a direct correlation between coagulation factor levels, thrombotic risks and bleeding propensity has long been hampered by an inability to selectively and specifically inhibit coagulation factor levels. Here, the exquisite selectivity of gene silencing combined with a gene knockout (KO) approach was used to define the relative contribution of factor IX (fIX) to thrombosis and primary haemostasis in the rat. Using a lipid nanoparticle (LNP) formulation, we successfully delivered fIX siRNAs to the liver by intravenous administration. The knockdown (KD) of target gene mRNA was achieved rapidly (within 24 hour post-siRNA dosing), sustained (maintained for at least 7 days post dosing) and not associated with changes in mRNA expression levels of other coagulation factors. We found that intermediate levels of liver fIX mRNA silencing (60-95 %) translating into a 50-99 % reduction of plasma fIX activity provided protection from thrombosis without prolonging the cuticle bleeding time. Over 99 % inhibition of fIX activity was required to observe increase in bleeding, a phenotype confirmed in fIX KO rats. These data provide substantial evidence of a participation of fIX in the mechanisms regulating thrombosis prior to those regulating primary haemostasis, therefore highlighting the potential of fIX as a therapeutic target. In addition, hepatic mRNA silencing using LNP-encapsulated siRNAs may represent a promising novel approach for the chronic treatment and prevention of coagulation-dependent thrombotic disorders in humans.
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Affiliation(s)
| | - Marija Tadin-Strapps
- Marija Tadin-Strapps, Department of Genetics and Pharmacogenomics, Merck Research Laboratories, Merck & Co., Inc., 33 Avenue E Louis Pasteur, Boston, MA 02115, USA, Tel.:+1 617 992 2339, E-mail:
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - Patrick Andre
- Patrick Andre, Cardiometabolic Disease, Merck & Co., Inc., Galloping Hill Road, Kenilworth, NJ 07033, USA, Tel.:+1 908 740 7329, E-mail:
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16
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Pharmacokinetics of recombinant and plasma-derived factor IX products in pediatric patients with severe hemophilia B. Blood Coagul Fibrinolysis 2015; 26:113-4. [DOI: 10.1097/mbc.0000000000000189] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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17
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Powell J, Shapiro A, Ragni M, Negrier C, Windyga J, Ozelo M, Pasi J, Baker R, Potts J, Li S, Mei B, Pierce GF, Robinson B. Switching to recombinant factor IX Fc fusion protein prophylaxis results in fewer infusions, decreased factor IX consumption and lower bleeding rates. Br J Haematol 2015; 168:113-23. [PMID: 25209873 DOI: 10.1111/bjh.13109] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2014] [Accepted: 07/29/2014] [Indexed: 01/25/2023]
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.
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Affiliation(s)
- Jerry Powell
- University of California Davis, Sacramento, CA, USA
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18
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Berger K, Schopohl D, Hilger A, Behr Gross ME, Giangrande P, Peyvandi F, Seitz R, Schramm W. Research in haemophilia B - approaching the request for high evidence levels in a rare disease. Haemophilia 2014; 21:4-20. [DOI: 10.1111/hae.12603] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/07/2014] [Indexed: 01/01/2023]
Affiliation(s)
- K. Berger
- Department of Haematology/Oncology; University Hospital of Munich; Munich Germany
| | - D. Schopohl
- Department of Haematology/Oncology; University Hospital of Munich; Munich Germany
| | - A. Hilger
- Paul-Ehrlich-Institute; Langen Germany
| | - M. -E. Behr Gross
- European Directorate for the Quality of Medicines & HealthCare (EDQM); Council of Europe; Strasbourg France
| | - P. Giangrande
- Oxford Haemophilia & Thrombosis Centre; Oxford University Hospitals NHS Trust; Oxford Oxfordshire UK
| | - F. Peyvandi
- Department of Pathophysiology and Transplantation; Angelo Bianchi Bonomi Haemophilia and Thrombosis Center; Fondazione IRCCS Cà Granda Ospedale Maggiore Policlinico; Università degli Studi di Milano; Luigi Villa Foundation; Milan Italy
| | - R. Seitz
- Paul-Ehrlich-Institute; Langen Germany
| | - W. Schramm
- Rudolf-Marx-Foundation; University of Munich; Munich Germany
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19
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Alamelu J, Bevan D, Sorensen B, Rangarajan S. Pharmacokinetic and pharmacodynamic properties of plasma-derived vs. recombinant factor IX in patients with hemophilia B: a prospective crossover study. J Thromb Haemost 2014; 12:2044-8. [PMID: 25315324 DOI: 10.1111/jth.12756] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2014] [Accepted: 10/12/2014] [Indexed: 08/31/2023]
Abstract
BACKGROUND Effective treatment of acute bleeding episodes in patients with hemophilia B relies on factor IX recovery, with higher levels being more desirable, whereas prevention of bleeds with a prophylactic regimen depends on the half-life of the product. Lower recovery values have been reported following administration of recombinant FIX (rFIX) than following administration of plasma-derived FIX (pdFIX). OBJECTIVES To compare the pharmacokinetic and pharmacodynamic properties of rFIX and pdFIX in patients with hemophilia B. METHODS A prospective crossover study of nine patients with moderate to severe hemophilia B was performed. Following a washout period, 50 U kg(-1) FIX was administered, and blood samples were taken as per protocol up to 48 h postinfusion. Paired data were analyzed with the Wilcoxon signed rank test. RESULTS Mean peak recovery at 10 min postinfusion was 62.14 IU dL(-1) with pdFIX and 52.7 IU dL(-1) with rFIX (P = 0.08). Mean half-life was 16.6 h with pdFIX and 17.5 h with rFIX (P = 0.55). Maximum peak thrombin generation (PTG) was 35.9 nm with pdFIX and 28.9 nm with rFIX (P = 0.21). Administration of rFIX resulted in early PTG, whereas administration of pdFIX resulted in slightly later and sustained PTG. At 48 h, PTG was similar with pdFIX (19.0 nm) and rFIX (19.4 nm) (P = 0.91). CONCLUSIONS Patients experienced better recovery with pdFIX than with rFIX. pdFIX and rFIX had similar half-lives. Maximum PTG was higher for pdFIX; however, this difference did not reach statistical significance. The clinical impact of the slightly increased, delayed and sustained PTG with pdFIX requires further investigation.
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Affiliation(s)
- J Alamelu
- Centre for Haemostasis and Thrombosis, Guy's and St Thomas' NHS Foundation Trust, London, UK
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20
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Sommer JM, Buyue Y, Bardan S, Peters RT, Jiang H, Kamphaus GD, Gray E, Pierce GF. Comparative field study: impact of laboratory assay variability on the assessment of recombinant factor IX Fc fusion protein (rFIXFc) activity. Thromb Haemost 2014; 112:932-40. [PMID: 25144892 PMCID: PMC6374931 DOI: 10.1160/th13-11-0971] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2013] [Accepted: 05/23/2014] [Indexed: 11/05/2022]
Abstract
Due to variability in the one-stage clotting assay, the performance of new factor IX (FIX) products should be assessed in this assay. The objective of this field study was to evaluate the accuracy of measuring recombinant FIX Fc fusion protein (rFIXFc) activity in clinical haemostasis laboratories using the one-stage clotting assay. Human haemophilic donor plasma was spiked with rFIXFc or BeneFIX® at 0.80, 0.20, or 0.05 IU/ml based on label potency. Laboratories tested blinded samples using their routine one-stage assay and in-house FIX plasma standard. The mean spike recoveries for BeneFIX (n=30 laboratories) were 121 %, 144 %, and 168 % of expected at nominal 0.80, 0.20, and 0.05 IU/ml concentrations, respectively. Corresponding rFIXFc spike recoveries were 88 %, 107 %, and 132 % of expected, respectively. All BeneFIX concentrations were consistently overestimated by most laboratories. rFIXFc activity was reagent-dependent; ellagic acid and silica gave higher values than kaolin, which underestimated rFIXFc. BeneFIX demonstrated significantly reduced chromogenic assay activity relative to one-stage assay results and nominal activity, while rFIXFc activity was close to nominal activity at three concentrations with better dilution linearity than the typical one-stage assay. In conclusion, laboratory- and reagent-specific assay variabilities were revealed, with progressively higher variability at lower FIX concentrations. Non-parallelism against the FIX plasma standard was observed in all one-stage assays with rFIXFc and BeneFIX, leading to significant overestimation of FIX activity at lower levels and generally high inter-laboratory variability. Compared to the accuracy currently achieved in clinical laboratories when measuring other rFIX products, most laboratories measured rFIXFc activity with acceptable accuracy and reliability using routine one-stage assay methods and commercially available plasma standards.
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Affiliation(s)
- Jurg M Sommer
- Jurg M. Sommer, PhD, Biogen Idec, 14 Cambridge Center, Cambridge, MA 02142, USA, Tel: +1 617 914 6937, Fax: +1 888 693 8149, E-mail:
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21
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Ducore JM, Miguelino MG, Powell JS. Alprolix (recombinant Factor IX Fc fusion protein): extended half-life product for the prophylaxis and treatment of hemophilia B. Expert Rev Hematol 2014; 7:559-71. [DOI: 10.1586/17474086.2014.951322] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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22
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Solano Trujillo MH, Stasyshyn O, Rusen L, Serban M, Lamas JL, Perina FG, Urasinski T, Oh M, Knowlton WB, Valenta-Singer B, Pavlova BG, Abbuehl B. Safe switching from a pdFIX (Immunine®) to a rFIX (Bax326). Haemophilia 2014; 20:674-81. [DOI: 10.1111/hae.12444] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2014] [Accepted: 03/19/2014] [Indexed: 11/27/2022]
Affiliation(s)
| | - O. Stasyshyn
- Institute of Blood Pathology and Transfusion Medicine of Academy of Medical Sciences of Ukraine; Lviv Ukraine
| | - L. Rusen
- S.C. Sanador SRL; Bucharest Romania
| | - M. Serban
- Louis Turcanu Emergency Clinical Children′s Hospital; Timisoara Romania
| | | | - F. G. Perina
- Regional Clinical Hospital Ekaterinburg; Ekaterinburg Russia
| | - T. Urasinski
- Department of Paediatrics, Paediatric Hematology and Oncology; Pomeranian Medical University; Szczecin Poland
| | - M. Oh
- Baxter Healthcare Corporation; Westlake Village CA USA
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23
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Powell JS, Pasi KJ, Ragni MV, Ozelo MC, Valentino LA, Mahlangu JN, Josephson NC, Perry D, Manco-Johnson MJ, Apte S, Baker RI, Chan GC, Novitzky N, Wong RS, Krassova S, Allen G, Jiang H, Innes A, Li S, Cristiano LM, Goyal J, Sommer JM, Dumont JA, Nugent K, Vigliani G, Brennan A, Luk A, Pierce GF. Phase 3 study of recombinant factor IX Fc fusion protein in hemophilia B. N Engl J Med 2013; 369:2313-23. [PMID: 24304002 DOI: 10.1056/nejmoa1305074] [Citation(s) in RCA: 263] [Impact Index Per Article: 23.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
BACKGROUND Prophylactic factor replacement in patients with hemophilia B improves outcomes but requires frequent injections. A recombinant factor IX Fc fusion protein (rFIXFc) with a prolonged half-life was developed to reduce the frequency of injections required. METHODS We conducted a phase 3, nonrandomized, open-label study of the safety, efficacy, and pharmacokinetics of rFIXFc for prophylaxis, treatment of bleeding, and perioperative hemostasis in 123 previously treated male patients. All participants were 12 years of age or older and had severe hemophilia B (endogenous factor IX level of ≤2 IU per deciliter, or ≤2% of normal levels). The study included four treatment groups: group 1 received weekly dose-adjusted prophylaxis (50 IU of rFIXFc per kilogram of body weight to start), group 2 received interval-adjusted prophylaxis (100 IU per kilogram every 10 days to start), group 3 received treatment as needed for bleeding episodes (20 to 100 IU per kilogram), and group 4 received treatment in the perioperative period. A subgroup of group 1 underwent comparative sequential pharmacokinetic assessments of recombinant factor IX and rFIXFc. The primary efficacy end point was the annualized bleeding rate, and safety end points included the development of inhibitors and adverse events. RESULTS As compared with recombinant factor IX, rFIXFc exhibited a prolonged terminal half-life (82.1 hours) (P<0.001). The median annualized bleeding rates in groups 1, 2, and 3 were 3.0, 1.4, and 17.7, respectively. In group 2, 53.8% of participants had dosing intervals of 14 days or more during the last 3 months of the study. In groups 1, 2 and 3, 90.4% of bleeding episodes resolved after one injection. Hemostasis was rated as excellent or good during all major surgeries. No inhibitors were detected in any participants receiving rFIXFc; in groups 1, 2, and 3, 73.9% of participants had at least one adverse event, and serious adverse events occurred in 10.9% of participants. These events were mostly consistent with those expected in the general population of patients with hemophilia. CONCLUSIONS Prophylactic rFIXFc, administered every 1 to 2 weeks, resulted in low annualized bleeding rates in patients with hemophilia B. (Funded by Biogen Idec; ClinicalTrials.gov number, NCT01027364.).
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