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Fager AM, Ellsworth P, Key NS, Monroe DM, Hoffman M. Emicizumab promotes factor Xa generation on endothelial cells. J Thromb Haemost 2024; 22:1605-1615. [PMID: 38460838 DOI: 10.1016/j.jtha.2024.02.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Revised: 01/31/2024] [Accepted: 02/26/2024] [Indexed: 03/11/2024]
Abstract
BACKGROUND Until recently, the treatment of hemophilia A relied on factor (F)VIII replacement. However, up to one-third of patients with severe hemophilia A develop neutralizing alloantibodies that render replacement therapies ineffective. The development of emicizumab, a bispecific antibody that partially mimics FVIIIa, has revolutionized the treatment of these patients. However, the use of an activated prothrombin complex concentrate [FEIBA (Takeda)] to treat breakthrough bleeding in patients on emicizumab has been associated with thrombotic complications including a unique microangiopathy. OBJECTIVES We hypothesized that the thrombotic complications observed with the combination of emicizumab and FEIBA might be due to excessive expression of procoagulant activity on the surface of endothelial cells. METHODS We examined the ability of emicizumab to promote FX activation on endothelial cells using 2 cell culture models. RESULTS We found that endothelial cells readily support emicizumab-mediated activation of FX by FIXa. The level of FXa generation depends on the concentration of available FIXa. The addition of FEIBA to emicizumab increased FXa generation in a dose-dependent manner on endothelial cells in both models. The rate of FXa generation was further enhanced by endothelial cell activation. However, unlike emicizumab, we found limited FXa generation in the presence of FVIII(a), which followed a significant lag time and was not dependent on FIXa concentration under these conditions. CONCLUSION Emicizumab promotes FXa generation on the surface of endothelial cells, which is markedly enhanced in the presence of FEIBA. These findings demonstrate a potential mechanism for the thrombotic complications seen with the combined use of emicizumab and FEIBA.
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Affiliation(s)
- Ammon M Fager
- Hematology/Oncology Service, Department of Veterans Affairs Medical Center, Durham, North Carolina, USA; Division of Hematology, Department of Medicine, Duke University School of Medicine, Durham, North Carolina, USA.
| | - Patrick Ellsworth
- Department of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA; Blood Research Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Nigel S Key
- Department of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA; Blood Research Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA; Department of Laboratory Medicine and Pathology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Dougald M Monroe
- Blood Research Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Maureane Hoffman
- Pathology and Laboratory Medicine Service, Department of Veterans Affairs Medical Center, Durham, North Carolina, USA; Department of Pathology, Duke University School of Medicine, Durham, North Carolina, USA
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2
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Miesbach W, Carcao M, Mahlangu J, Dargaud Y, Jimenez-Yuste V, Hermans C. Eptacog beta for the management of patients with haemophilia A and B with inhibitors: A European perspective. Haemophilia 2024; 30:257-266. [PMID: 38317441 DOI: 10.1111/hae.14944] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Revised: 09/25/2023] [Accepted: 10/20/2023] [Indexed: 02/07/2024]
Abstract
Eptacog beta (activated), a recombinant human factor VIIa (rFVIIa), was approved by the US Food and Drug Administration (FDA) in 2020 (SEVENFACT®, LFB & HEMA Biologics) and the European Medicines Agency (EMA) in 2022 (CEVENFACTA®, LFB). In Europe, eptacog beta is indicated for the treatment of bleeds and the prevention of bleeds during surgery or invasive procedures in adults and adolescents (≥12 years old) with congenital haemophilia A or B with high-titre inhibitors (≥5 BU) or with low-titre inhibitors who are expected to have a high anamnestic response to factor VIII or factor IX, or to be refractory to increased dosing of these factors. The efficacy and safety of eptacog beta were evaluated in three Phase III clinical studies, PERSEPT 1, 2 and 3. For the EMA filing dossier, the analysis of data from PERSEPT 1 and 2 differed from the analysis used to support the filing in the US. In this review, we summarise current data regarding the mode of action, clinical efficacy and safety of eptacog beta for the management of haemophilia A and B in patients with inhibitors from a European perspective. In addition to providing a valuable summary of the analyses of the clinical data for eptacog beta conducted for the EMA, our review summarises the potential differentiators for eptacog beta compared with other current bypassing agents.
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Affiliation(s)
- Wolfgang Miesbach
- Department of Haemostaseology and Hemophilia Center, Medical Clinic 2, Institute of Transfusion Medicine, University Hospital Frankfurt, Frankfurt, Germany
| | - Manuel Carcao
- The Hospital for Sick Children and University of Toronto, Toronto, Canada
| | - Johnny Mahlangu
- Haemophilia Comprehensive Care Centre, Faculty of Health Sciences, University of the Witwatersrand and National Health Laboratory Service, Johannesburg, South Africa
| | - Yesim Dargaud
- Clinical Haemostasis Unit and Lyon Haemophilia Centre, Louis Pradel Hospital, Lyon, France
| | | | - Cédric Hermans
- Haemostasis and Thrombosis Unit, Division of Haematology, Cliniques Universitaires Saint-Luc, Université catholique de Louvain (UCLouvain), Brussels, Belgium
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3
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Andreeva TA, Zharkov PA, Zozulya NI, Zorenko VY, Konstantinova VN, Lavrentieva IN, Davydkin IL, Petrov VY, Polyanskaya TY, Soldatenkov VE, Shutov SA. [Methodological recommendations for surgical care in patients with hemophilia A receiving prophylactic therapy with emicizumab]. Khirurgiia (Mosk) 2024:3-20. [PMID: 38591217 DOI: 10.17116/hirurgia20240323] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/10/2024]
Abstract
Methodological recommendations for surgical care in patients with hemophilia A receiving prophylactic therapy with emicizumab. Recommendations of the expert group. Moscow, 2024.
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Affiliation(s)
- T A Andreeva
- GBUZ "City Polyclinic #37", City Hemophilia Treatment Center, St. Petersburg, Russian Federation
| | - P A Zharkov
- FGBU "National Medical Research Center of Pediatric Hematology, Oncology and Immunology named after Dmitry Rogachev", St. Petersburg, Russia
| | - N I Zozulya
- FGBU "National Medical Research Center of Hematology", Ministry of Health of the Russian Federation, Moscow, Russian Federation
| | - V Y Zorenko
- FGBU "National Medical Research Center of Hematology", Ministry of Health of the Russian Federation, Moscow, Russian Federation
| | - V N Konstantinova
- GBUZ "City Polyclinic #37", City Hemophilia Treatment Center, St. Petersburg, Russian Federation
| | - I N Lavrentieva
- GBUZ "Morozov Children's City Clinical Hospital of the Moscow City Health Department", Moscow, Russian Federation
| | - I L Davydkin
- FGBOU VO "Samara State Medical University", Ministry of Health of the Russian Federation, Samara, Russian Federation
| | - V Y Petrov
- GBUZ "Morozov Children's City Clinical Hospital of the Moscow City Health Department", Moscow, Russian Federation
| | - T Yu Polyanskaya
- FGBU "National Medical Research Center of Hematology", Ministry of Health of the Russian Federation, Moscow, Russian Federation
| | - V E Soldatenkov
- FGBU "Russian Research Institute of Hematology and Transfusiology FMBA", St. Petersburg, Russian Federation
| | - S A Shutov
- FGBU "National Medical Research Center of Hematology", Ministry of Health of the Russian Federation, Moscow, Russian Federation
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4
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Holle LA, Pantazis JC, Turecek PL, Wolberg AS. Clot formation and fibrinolysis assays reveal functional differences among hemostatic agents in hemophilia A plasma. Res Pract Thromb Haemost 2024; 8:102337. [PMID: 38426025 PMCID: PMC10901841 DOI: 10.1016/j.rpth.2024.102337] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2023] [Revised: 12/21/2023] [Accepted: 01/16/2024] [Indexed: 03/02/2024] Open
Abstract
Background Measuring the activity of hemostatic agents used to treat hemophilia A often requires drug-specific assays. In vitro assays show hemophilic clots have abnormal characteristics, including prolonged clotting time and decreased resistance to fibrinolysis. The ability of certain agents to correct these parameters in vitro is associated with hemostatic efficacy in vivo. Objectives To compare effects of established and emerging hemostatic agents on clot formation and fibrinolysis in hemophilia A plasma. Methods Pooled and individual hemophilia A platelet-poor plasmas were spiked with replacement (recombinant factor VIII [rFVIII], PEGylated rFVIII, polysialylated rFVIII, and porcine rFVIII) or bypassing (emicizumab, rFVIIa, and activated prothrombin complex concentrate) products. Effects on tissue factor-initiated clot formation and fibrinolysis were measured by turbidity. Results Compared to normal pooled plasma, hemophilia-pooled plasma showed reduced clot formation and increased fibrinolysis, and all replacement agents improved these characteristics. rFVIII and PEGylated rFVIII produced similar effects at similar concentrations, whereas polysialylated rFVIII produced slightly higher and porcine rFVIII slightly lower effects at these concentrations. Bypassing agents enhanced clot formation and stability, but patterns differed from replacement agents. The clotting rate showed a concentration-response relationship for all agents. High concentrations of all products produced effects that exceeded the normal range in at least some parameters. Responses of individual donors varied, but all agents improved clot formation and stability in all donors tested. Conclusion Clotting and fibrinolysis assays reveal hemostatic effects of replacement and bypassing therapies at clinically relevant concentrations. These assays may help characterize hemostatic agents and optimize dosing.
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Affiliation(s)
- Lori A. Holle
- Department of Pathology and Laboratory Medicine and UNC Blood Research Center, University of North Carolina, Chapel Hill, North Carolina, USA
| | - Jacob C. Pantazis
- Department of Pathology and Laboratory Medicine and UNC Blood Research Center, University of North Carolina, Chapel Hill, North Carolina, USA
| | - Peter L. Turecek
- Plasma-Derived Therapies R&D, Baxalta Innovations GmbH – Takeda, Vienna, Austria
| | - Alisa S. Wolberg
- Department of Pathology and Laboratory Medicine and UNC Blood Research Center, University of North Carolina, Chapel Hill, North Carolina, USA
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5
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Atsou S, Schellenberg C, Lagrange J, Lacolley P, Lenting PJ, Denis CV, Christophe OD, Regnault V. Thrombin generation on vascular cells in the presence of factor VIII and/or emicizumab. J Thromb Haemost 2024; 22:112-125. [PMID: 37776978 DOI: 10.1016/j.jtha.2023.09.017] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Revised: 08/18/2023] [Accepted: 09/16/2023] [Indexed: 10/02/2023]
Abstract
BACKGROUND The effect of factor VIII (FVIII) or emicizumab on thrombin generation is usually assessed in assays using synthetic phospholipids. Here, we assessed thrombin generation at the surface of human arterial cells (aortic endothelial cells [hAECs] and aortic vascular smooth muscle cells [hVSMCs]). OBJECTIVES To explore the capacity of hAECs (resting or stimulated) and hVSMCs to support thrombin generation by FVIII or emicizumab. METHODS Primary hVSMCs and hAECs were analyzed for tissue factor (TF)-activity and antigen, phosphatidylserine (PS)-exposure, tissue factor pathway inhibitor (TFPI)-content and thrombomodulin expression. Cells were incubated with FVIII-deficient plasma spiked with FVIII, emicizumab, activated prothrombin complex concentrate (APCC) or combinations thereof. RESULTS TF activity and PS-exposure were present on both hVSMCs and hAECs. In contrast, thrombomodulin and TFPI were expressed on hAECs, while virtually lacking on hVSMCs, confirming the procoagulant nature of hVSMCs. Tumor necrosis factor α-mediated stimulation of hAECs increased not only TF antigen, TF activity, and PS-exposure but also TFPI and thrombomodulin expression. As expected, FVIII and emicizumab promoted thrombin generation on nonstimulated hAECs and hVSMCs, with more thrombin being generated on hVSMCs. Unexpectedly, FVIII and emicizumab increased thrombin generation to a lesser extent on stimulated hAECs compared with nonstimulated hAECs. Finally, adding emicizumab to FVIII did not further increase thrombin generation, whereas the addition of emicizumab to APCC resulted in exaggerated thrombin generation. CONCLUSION Tumor necrosis factor stimulation of hAECs increases both pro- and anticoagulant activity. Unexpectedly, the increased anticoagulant activity is sufficient to limit both FVIII- and emicizumab-induced thrombin generation. This protective effect disappears when emicizumab is combined with APCC.
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Affiliation(s)
- Sénadé Atsou
- Université Paris-Saclay, INSERM, Hémostase Inflammation Thrombose HITh U1176, 94276, Le KremLin-Bicêtre, France
| | - Célia Schellenberg
- Université de Lorraine, INSERM, Défaillance Cardiovasculaire Aigüe et Chronique DCAC U1116, 54505 Vandoeuvre-les-Nancy, France
| | - Jeremy Lagrange
- Université de Lorraine, INSERM, Défaillance Cardiovasculaire Aigüe et Chronique DCAC U1116, 54505 Vandoeuvre-les-Nancy, France
| | - Patrick Lacolley
- Université de Lorraine, INSERM, Défaillance Cardiovasculaire Aigüe et Chronique DCAC U1116, 54505 Vandoeuvre-les-Nancy, France
| | - Peter J Lenting
- Université Paris-Saclay, INSERM, Hémostase Inflammation Thrombose HITh U1176, 94276, Le KremLin-Bicêtre, France.
| | - Cécile V Denis
- Université Paris-Saclay, INSERM, Hémostase Inflammation Thrombose HITh U1176, 94276, Le KremLin-Bicêtre, France. https://twitter.com/InsermU1176
| | - Olivier D Christophe
- Université Paris-Saclay, INSERM, Hémostase Inflammation Thrombose HITh U1176, 94276, Le KremLin-Bicêtre, France
| | - Véronique Regnault
- Université de Lorraine, INSERM, Défaillance Cardiovasculaire Aigüe et Chronique DCAC U1116, 54505 Vandoeuvre-les-Nancy, France
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Bertaggia Calderara D, Marchi Cappelletti R, Batista Mesquita Sauvage AP, Durual S, Gomez FJ, Zermatten MG, Aliotta A, Casini A, Alberio L. Pharmacodynamics Monitoring of Emicizumab in Patients with Hemophilia A. Thromb Haemost 2023; 123:955-965. [PMID: 37336473 DOI: 10.1055/s-0043-1769788] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/21/2023]
Abstract
BACKGROUND Emicizumab is a bispecific antibody mimicking coagulation factor VIII (FVIII) employed to treat patients with hemophilia A (PwHA) regardless of FVIII inhibitor status. The identification of biological markers reflecting the hemostatic competence of patients under emicizumab therapy would have a great clinical value. Unfortunately, emicizumab over-corrects standard coagulation assays, precluding their use for evaluating the hemostatic correction achieved in vivo. Here, we investigated whether global coagulation assays (GCA) would allow monitoring the biological response to non-factor replacement therapy with emicizumab. MATERIALS AND METHODS Six adults PwHA received a weekly dose of emicizumab of 3 mg/kg during weeks (W) 1 4 and 1.5 mg/kg from W5 onwards. Response to treatment was monitored weekly by emicizumab plasma concentration, thrombin generation (TG), and fibrin clot formation (FCF) and structure. TG and FCF results were compared to patient baseline, FVIII replacement, and healthy donors. RESULTS TG and FCF significantly increased in PwHA after the loading period, reaching a plateau that lasted until the end of monitoring. Similarly, fibrin clot network became denser with thinner fibrin fibers. However, TG contrary to FCF remained at the lower limits of reference values. Remarkably, despite having similar plateau concentrations of emicizumab some patients showed markedly different degrees of TG and FCF improvement. CONCLUSION Our study enriches the knowledge on the use of GCA to monitor non-factor replacement therapy, indicating that TG and FCF could act as direct markers of emicizumab biological activity. GCA allow to capture and visualize the individually variable response to emicizumab, leading a step forward to the personalization of patient treatment.
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Affiliation(s)
- Debora Bertaggia Calderara
- Division of Hematology and Central Hematology Laboratory, Lausanne University Hospital (CHUV) and University of Lausanne (UNIL), Lausanne, Switzerland
| | - Rita Marchi Cappelletti
- Department of Genetic Medicine and Development, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Ana Patricia Batista Mesquita Sauvage
- Division of Hematology and Central Hematology Laboratory, Lausanne University Hospital (CHUV) and University of Lausanne (UNIL), Lausanne, Switzerland
| | - Stéphane Durual
- Biomaterials Laboratory, University Clinics of Dental Medicine, University of Geneva, Switzerland
| | - Francisco J Gomez
- Division of Hematology and Central Hematology Laboratory, Lausanne University Hospital (CHUV) and University of Lausanne (UNIL), Lausanne, Switzerland
| | - Maxime G Zermatten
- Division of Hematology and Central Hematology Laboratory, Lausanne University Hospital (CHUV) and University of Lausanne (UNIL), Lausanne, Switzerland
| | - Alessandro Aliotta
- Division of Hematology and Central Hematology Laboratory, Lausanne University Hospital (CHUV) and University of Lausanne (UNIL), Lausanne, Switzerland
| | - Alessandro Casini
- Department of Medicine, University of Geneva, Geneva, Switzerland
- Division of Angiology and Hemostasis, University Hospitals of Geneva, Geneva, Switzerland
| | - Lorenzo Alberio
- Division of Hematology and Central Hematology Laboratory, Lausanne University Hospital (CHUV) and University of Lausanne (UNIL), Lausanne, Switzerland
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7
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Nguyen NH, Jarvi NL, Balu-Iyer SV. Immunogenicity of Therapeutic Biological Modalities - Lessons from Hemophilia A Therapies. J Pharm Sci 2023; 112:2347-2370. [PMID: 37220828 DOI: 10.1016/j.xphs.2023.05.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2023] [Revised: 05/17/2023] [Accepted: 05/17/2023] [Indexed: 05/25/2023]
Abstract
The introduction and development of biologics such as therapeutic proteins, gene-, and cell-based therapy have revolutionized the scope of treatment for many diseases. However, a significant portion of the patients develop unwanted immune reactions against these novel biological modalities, referred to as immunogenicity, and no longer benefit from the treatments. In the current review, using Hemophilia A (HA) therapy as an example, we will discuss the immunogenicity issue of multiple biological modalities. Currently, the number of therapeutic modalities that are approved or recently explored to treat HA, a hereditary bleeding disorder, is increasing rapidly. These include, but are not limited to, recombinant factor VIII proteins, PEGylated FVIII, FVIII Fc fusion protein, bispecific monoclonal antibodies, gene replacement therapy, gene editing therapy, and cell-based therapy. They offer the patients a broader range of more advanced and effective treatment options, yet immunogenicity remains the most critical complication in the management of this disorder. Recent advances in strategies to manage and mitigate immunogenicity will also be reviewed.
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Affiliation(s)
- Nhan H Nguyen
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, University at Buffalo, Buffalo, NY, USA; Currently at Truvai Biosciences, Buffalo, NY, USA
| | - Nicole L Jarvi
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, University at Buffalo, Buffalo, NY, USA
| | - Sathy V Balu-Iyer
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, University at Buffalo, Buffalo, NY, USA.
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8
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Muniz RL, Camelo RM, Araújo MS, Barbosa MM, Guerra AA, Acurcio FDA, Alvares-Teodoro J. Efficacy/effectiveness and safety of emicizumab prophylaxis of people with hemophilia A: a systematic review and meta-analysis. Expert Rev Hematol 2023; 16:1087-1097. [PMID: 38066708 DOI: 10.1080/17474086.2023.2293096] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2023] [Accepted: 11/27/2023] [Indexed: 12/19/2023]
Abstract
BACKGROUND Emicizumab is a monoclonal antibody approved for prophylaxis against bleeds for people with hemophilia A (PwHA). A systematic review was conducted evaluating the efficacy/effectiveness and the safety of emicizumab as prophylaxis for PwHA compared to prophylaxis with factor VIII (FVIII) or bypassing agents (BPA), respectively in patients without and with inhibitors. RESEARCH DESIGN AND METHODS Database-directed search strategies were performed in Aug/26/2022 and updated in Mar/16/2023. Studies evaluating the prophylaxis with emicizumab versus prophylaxis with FVIII or BPA in PwHA without or with inhibitors, respectively, were selected by two independent reviewers. Data were extracted by two independent reviewers. Annualized bleeding rates for total treated bleeding events (ABR-all) were evaluated by meta-analysis. The quality of studies and certainty of evidence were assessed. RESULTS A total of 11 studies were included. The standard mean differences for ABR-all were -0.6 (95%CI -1.0 to -0.2, p-value = 0.0002), among PwHA without inhibitors, and -1.7 (95%CI -2.4 to -0.9, p-value <0.00001), among PwHA with inhibitors. However, there was moderate heterogeneity in both meta-analyses. The most frequent adverse event was injection site reaction. CONCLUSIONS Emicizumab prophylaxis was superior in reducing the ABR-all when compared with prophylaxis with FVIII or BPA.
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Affiliation(s)
- Roberto Lúcio Muniz
- Faculty of Pharmacy, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | | | - Maiara Silva Araújo
- Faculty of Pharmacy, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
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Yoneyama K, Schmitt C, Portron A, Kiialainen A, Kotani N, Jaminion F, Retout S, Adamkewicz JI. Clinical pharmacology of emicizumab for the treatment of hemophilia A. Expert Rev Clin Pharmacol 2023; 16:775-790. [PMID: 37529848 DOI: 10.1080/17512433.2023.2243213] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Revised: 06/22/2023] [Accepted: 07/28/2023] [Indexed: 08/03/2023]
Abstract
INTRODUCTION Emicizumab is a humanized bispecific antibody approved for the routine prophylaxis of bleeding episodes in patients with hemophilia A (PwHA) regardless of the presence of factor VIII (FVIII) inhibitors. It mimics the cofactor function of missing activated FVIII by bridging activated factor IX and factor X, thereby restoring hemostasis. AREAS COVERED This review covers the clinical pharmacology of emicizumab and the translation of its pharmacokinetics (PK) and pharmacodynamics (PD) to clinical efficacy and safety. The PK of emicizumab is linear, with an approximately 1-month half-life. Once-weekly to every-4-week subcutaneous (SC) administrations maintain effective trough concentrations throughout the dosing intervals, associated with a coagulation potential analogous to that in patients with mild hemophilia A. In combination with activated prothrombin complex concentrate, and to a lesser extent with recombinant activated factor VII, emicizumab exerts a synergistic effect, whereas combination with FVIII may result in a non-additive coagulation potential at normal FVIII activity. EXPERT OPINION The translation of emicizumab PK/PD into clinical effects was demonstrated in several phase III studies, which showed remarkable bleed control and a favorable safety profile in PwHA. These emicizumab attributes, together with the convenience of use (infrequent SC injections), offer a novel paradigm for the management of PwHA.
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10
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Valls R, Wagg J, Paz-Priel I, Man G, Artigas L, Jaccard G, Coma M, Schmitt C. Application of systems biology to identify pharmacological mechanisms of thrombotic microangiopathy evoked by combined activated prothrombin complex concentrate and emicizumab. Sci Rep 2023; 13:10078. [PMID: 37344529 DOI: 10.1038/s41598-023-36891-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Accepted: 06/12/2023] [Indexed: 06/23/2023] Open
Abstract
Emicizumab is a bispecific monoclonal antibody that substitutes for the function of missing or deficient factor VIII (FVIII) in people with hemophilia A (PwHA). Long-term safety and efficacy of emicizumab have been demonstrated in several clinical trials. Nevertheless, in the first of these, three cases of thrombotic microangiopathy (TMA) occurred in PwHA treated with emicizumab receiving high doses of activated prothrombin complex concentrate (aPCC), a bypassing agent used for treating breakthrough bleeds when FVIII neutralizing antibodies (inhibitors) make FVIII replacement ineffective. The aim of the present work is to offer a method to elucidate the pathophysiological and pharmacological mechanisms involved in this treatment-induced TMA. Systems biology and machine learning-based Therapeutic Performance Mapping System is a validated in silico technology that allowed us to construct models of potential mechanisms behind induced TMA. Two drug combinations were modeled and assessed: emicizumab plus aPCC and emicizumab plus recombinant activated factor VII (another bypassing agent). Our models showed that both combinations were related to activation of the coagulation cascade. However, mechanisms involved mainly in platelet activation and possibly in complement activation were detected only for emicizumab plus aPCC, potentially explaining the occurrence of TMA only in this combination.
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Affiliation(s)
| | - Jonathan Wagg
- Roche Innovation Center, Basel, Switzerland
- AC Immune SA, EPFL Innovation Park, Lausanne, Switzerland
| | - Ido Paz-Priel
- Genentech, Inc., South San Francisco, CA, USA
- Graphite Bio Inc., South San Francisco, CA, USA
| | - Gabriel Man
- Genentech, Inc., South San Francisco, CA, USA
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11
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El Maamari J, Amid A, Pelland-Marcotte MC, Tole S. Between Scylla and Charybdis: thrombosis in children with hemophilia. Front Pediatr 2023; 11:1173549. [PMID: 37287631 PMCID: PMC10242037 DOI: 10.3389/fped.2023.1173549] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/24/2023] [Accepted: 04/27/2023] [Indexed: 06/09/2023] Open
Abstract
Thromboembolism is an infrequent complication in children with hemophilia that has been traditionally associated with the presence of a central venous access device. Novel rebalancing agents have shown promising results as prophylactic therapies to minimize the risk of bleeding but both thromboembolism and thrombotic microangiopathy have been reported as complications. The management of thrombosis in children with hemophilia is particularly challenging given the inherent risk of bleeding. In this paper, we present clinical vignettes to review the literature, highlight challenges, and describe our approach to managing thromboembolism in children with hemophilia.
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Affiliation(s)
- Jad El Maamari
- Division of Pediatric Hematology/Oncology, Department of Pediatrics, BC Children’s Hospital, Vancouver, BC, Canada
| | - Ali Amid
- Division of Pediatric Hematology/Oncology, Department of Pediatrics, BC Children’s Hospital, Vancouver, BC, Canada
| | - Marie-Claude Pelland-Marcotte
- Division of Pediatric Hematology-Oncology, CHU deQuébec—Centre Mère-Enfant Soleil, Quebec City, QC, Canada
- Research Center of the CHU de Québec, Axe Reproduction, Santé de la Mère et de l’Enfant, Quebec City, Canada
| | - Soumitra Tole
- Department of Pediatrics, Schulich School of Medicine & Dentistry, Western University, London, ON, Canada
- Department of Pediatrics, Division of Hematology/Oncology, London Health Sciences Centre, London, ON, Canada
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12
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Lund J, Jensen K, Burnier L, Ezban M. In vitro effects of combining Mim8 with factor VIII, FVIIa, and activated prothrombin complex concentrates in thrombin generation assays. J Thromb Haemost 2023; 21:1493-1502. [PMID: 37037699 DOI: 10.1016/j.jtha.2023.03.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Revised: 02/09/2023] [Accepted: 03/07/2023] [Indexed: 04/12/2023]
Abstract
BACKGROUND Mim8 is a novel antifactor IXa/antifactor X bispecific antibody in clinical development for prophylactic treatment of hemophilia A with and without inhibitors. Patients treated with Mim8 may need supplementary bleed treatment under certain conditions such as surgery or major trauma. OBJECTIVES This study aimed to better understand the response of Mim8 in thrombin generation assays (TGAs) alone or in combination with other hemostatic proteins. METHODS We used TGAs with different activators (tissue factor (TF) and activated factor XI) to better understand the similarities and differences between the mode of action of Mim8 and factor VIII (FVIII). Following this, we investigated the effects of mixing Mim8 with the main bleed treatment options for persons with hemophilia A with or without inhibitors: FVIII, activated factor VII (FVIIa), and activated prothrombin complex concentrates (aPCC). RESULTS The results indicated that for patients without inhibitors, Mim8 does not interfere with FVIII's mode of action. For patients with inhibitors, Mim8 mixed with aPCC results in a strong synergistic effect causing thrombin generation far exceeding the normal levels. Contrary to this, mixing Mim8 with FVIIa results in a more controlled additive effect, visible only when using TF as a trigger, which does not exceed the normal level of thrombin generation. CONCLUSION These findings support the use of approved clinical doses of FVIIa for bleed treatment of patients with FVIII inhibitors treated with Mim8. Additionally, the findings suggest that concomitant use of FVIII and Mim8 is safe for managing breakthrough bleeds.
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13
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Nardi MA. Hemophilia A: Emicizumab monitoring and impact on coagulation testing. Adv Clin Chem 2023; 113:273-315. [PMID: 36858648 DOI: 10.1016/bs.acc.2022.12.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Hemophilia A is an X-linked recessive bleeding disorder characterized by absent or ineffective coagulation factor VIII, a condition that could result in a severe and potentially life-threatening bleed. Although the current standard of care involves prophylactic replacement therapy of factor VIII, the development of neutralizing anti-factor VIII alloantibody inhibitors often complicates such therapeutic treatment. Emicizumab (Hemlibra®), a novel recombinant therapeutic agent for patients with hemophilia A, is a humanized asymmetric bispecific IgG4 monoclonal antibody designed to mimic activated factor VIII by bridging factor IXa and factor X thus effecting hemostasis. Importantly, this drug eliminates the need for factor VIII and complications associated with inhibitor generation. Emicizumab has been approved for use in several countries including the United States and Japan for prophylaxis of bleeding episodes in hemophilia A with and without FVIII inhibitors. Therapy is also approved in the European Union for routine prophylaxis of bleeds in hemophilia A with inhibitors or severe hemophilia A without inhibitors. Unfortunately, emicizumab therapy presents unique challenges for routine and specialty coagulation tests currently used to monitor hemophilia A. In this review, hemophilia A is presented, the biochemistry of factor VIII is discussed, and the impact of the therapeutic agent emicizumab is highlighted.
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Affiliation(s)
- Michael A Nardi
- Department of Pediatrics, New York University Grossman School of Medicine, New York, NY, United States; Department of Pathology, New York University Grossman School of Medicine, New York, NY, United States.
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14
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Kizilocak H, Marquez-Casas E, Malvar J, Young G. Safety of FEIBA and emicizumab (SAFE): Dose escalation study evaluating the safety of in vivo administration of activated prothrombin complex concentrate in haemophilia A patients on emicizumab. Haemophilia 2023; 29:100-105. [PMID: 36287631 DOI: 10.1111/hae.14684] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Revised: 10/03/2022] [Accepted: 10/12/2022] [Indexed: 01/25/2023]
Abstract
INTRODUCTION Emicizumab is a humanized bispecific monoclonal antibody licensed for patients with severe haemophilia A. Breakthrough bleeding still occurs in patients on emicizumab and can be managed with recombinant factor VIIa (rFVIIa) or activated prothrombin complex concentrate (aPCC). Thrombotic events were reported when patients on emicizumab received concomitant aPCC at relatively high doses. We studied the effect of infusing various doses of aPCC to patients on emicizumab. MATERIAL AND METHODS Nine patients with severe haemophilia A with inhibitors who are on emicizumab were recruited to participate. Patients were infused with varying doses of aPCC in vivo. Samples were tested with thrombin generation (TG) assay. RESULTS In the current in vivo arm of the study four out of nine patients reached the highest dose, 75 U/kg of aPCC and six out of nine patients were actually eligible for the highest dose. In the previous in vitro arm of the study seven out of eight patients reached the normal plasma with spiking aPCC at a very low concentration equivalent to 5 U/kg. CONCLUSION The in vitro portion of the study demonstrated that clinically relevant concentrations of aPCC resulted in excessive TG, however, in vivo administration of aPCC to the same patients demonstrated that most of the patients had normal TG at the approved doses of aPCC. In the management of breakthrough bleeding clinicians should heed the boxed warning for concomitant use of emicizumab and aPCC, however, should also be aware that low doses of aPCC may not result in sufficient TG.
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Affiliation(s)
- Hande Kizilocak
- Children's Hospital Los Angeles, Hemostasis and Thrombosis Center, Los Angeles, California, USA
| | - Elizabeth Marquez-Casas
- Children's Hospital Los Angeles, Hemostasis and Thrombosis Center, Los Angeles, California, USA
| | - Jemily Malvar
- Children's Hospital Los Angeles, Cancer and Blood Disease Institute, Los Angeles, California, USA
| | - Guy Young
- Children's Hospital Los Angeles, Hemostasis and Thrombosis Center, Los Angeles, California, USA.,University of Southern California, Keck School of Medicine, Los Angeles, California, USA
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15
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Valke LLFG, Rijpma S, Meijer D, Schols SEM, van Heerde WL. Thrombin generation assays to personalize treatment in bleeding and thrombotic diseases. Front Cardiovasc Med 2022; 9:1033416. [PMID: 36440026 PMCID: PMC9684194 DOI: 10.3389/fcvm.2022.1033416] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Accepted: 10/26/2022] [Indexed: 07/30/2023] Open
Abstract
Treatment of bleeding and thrombotic disorders is highly standardized and based on evidence-based medicine guidelines. These evidence-based treatment schemes are well accepted but may lead to either insufficient treatment or over-dosing, because the individuals' hemostatic properties are not taken into account. This can potentially introduce bleeding or thrombotic complications in individual patients. With the incorporation of pharmacokinetic (PK) and pharmacodynamic (PK-PD) parameters, based on global assays such as thrombin generation assays (TGAs), a more personalized approach can be applied to treat either bleeding or thrombotic disorders. In this review, we will discuss the recent literature about the technical aspects of TGAs and the relation to diagnosis and management of bleeding and thrombotic disorders. In patients with bleeding disorders, such as hemophilia A or factor VII deficiency, TGAs can be used to identify patients with a more severe bleeding phenotype and also in the management with non-replacement therapy and/or bypassing therapy. These assays have also a role in patients with venous thrombo-embolism, but the usage of TGAs in patients with arterial thrombosis is less clear. However, there is a potential role for TGAs in the monitoring of (long-term) antithrombotic therapy, for example with the use of direct oral anticoagulants. Finally this review will discuss controversies, limitations and knowledge gaps in relation to the introduction of TGAs to personalize medicine in daily medical practice.
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Affiliation(s)
- Lars L. F. G. Valke
- Department of Hematology, Radboud University Medical Center, Nijmegen, Netherlands
- Hemophilia Treatment Center, Nijmegen, Netherlands
| | - Sanna Rijpma
- Department of Laboratory Medicine, Laboratory of Hematology, Radboud University Medical Center, Nijmegen, Netherlands
| | - Danielle Meijer
- Department of Laboratory Medicine, Laboratory of Hematology, Radboud University Medical Center, Nijmegen, Netherlands
| | - Saskia E. M. Schols
- Department of Hematology, Radboud University Medical Center, Nijmegen, Netherlands
- Hemophilia Treatment Center, Nijmegen, Netherlands
| | - Waander L. van Heerde
- Department of Hematology, Radboud University Medical Center, Nijmegen, Netherlands
- Hemophilia Treatment Center, Nijmegen, Netherlands
- Enzyre BV, Novio Tech Campus, Nijmegen, Netherlands
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16
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GÖK V, ÜNAL E. Comprehensive approach to hemophilia. JOURNAL OF HEALTH SCIENCES AND MEDICINE 2022. [DOI: 10.32322/jhsm.1108174] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
Hemophilia A, B are X-linked recessive bleeding disorder that typically results from a deficiency of clotting factor VIII (FVIII) and factor IX (FIX). The severity of the disease is determined according to the FVIII and FIX levels. Hemophilia A and B have similar symptoms and are both characterized by bleeding, particularly in large joints such as ankles, knees, elbows. Recurrent bleeding in joints eventually causes progressive hemophilic arthropathy. Life-threatening hemorrhages may occur rarely. Treatment of hemophilia has improved significantly in recent years with clotting factor concentrates. The average life expectancy was
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Xu R, Kalluri AL, Sun LR, Lawrence CE, Lee JK, Kannan S, Cohen AR. The neurosurgical management of Severe Hemophilia A and Moyamoya (SHAM): challenges, strategies, and literature review. Childs Nerv Syst 2022; 38:1077-1084. [PMID: 35262754 DOI: 10.1007/s00381-022-05489-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Accepted: 03/03/2022] [Indexed: 11/29/2022]
Abstract
INTRODUCTION Severe Hemophilia A and Moyamoya arteriopathy (SHAM syndrome) is a rare genetic disorder caused by deletion of portions of the cytogenic band Xq28. A case of SHAM syndrome requiring bilateral cerebral revascularization is described with an emphasis on perioperative management. CASE REPORT A 5-year-old boy with severe hemophilia A complicated by factor VIII inhibition presented with right-sided weakness. Imaging revealed multiple strokes and vascular changes consistent with Moyamoya disease. The patient underwent two-staged indirect cerebral bypass revascularizations, first on the left side and several months later on the right. Perioperative management required balancing the administration of agents to prevent coagulopathy and perioperative hemorrhage while mitigating the risk of thromboembolic events associated with bypass surgery. Despite a multidisciplinary effort by the neurosurgery, hematology, critical care, and anesthesiology teams, the post-operative course after both surgeries was complicated by stroke. Fortunately, the patient recovered rapidly to his preoperative functional baseline. CONCLUSION We describe a rare case of SHAM syndrome in a pediatric patient who required bilateral revascularizations and discuss strategies for managing the perioperative risk of hemorrhage and stroke. We also review existing literature on SHAM syndrome.
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Affiliation(s)
- Risheng Xu
- Johns Hopkins University School of Medicine, Phipps Building 554, 600 N Wolfe St, Baltimore, MD, 21287, USA
| | - Anita L Kalluri
- Johns Hopkins University School of Medicine, Phipps Building 554, 600 N Wolfe St, Baltimore, MD, 21287, USA
| | - Lisa R Sun
- Johns Hopkins University School of Medicine, Phipps Building 554, 600 N Wolfe St, Baltimore, MD, 21287, USA
| | - Courtney E Lawrence
- Johns Hopkins University School of Medicine, Phipps Building 554, 600 N Wolfe St, Baltimore, MD, 21287, USA
| | - Jennifer K Lee
- Johns Hopkins University School of Medicine, Phipps Building 554, 600 N Wolfe St, Baltimore, MD, 21287, USA
| | - Sujatha Kannan
- Johns Hopkins University School of Medicine, Phipps Building 554, 600 N Wolfe St, Baltimore, MD, 21287, USA
| | - Alan R Cohen
- Johns Hopkins University School of Medicine, Phipps Building 554, 600 N Wolfe St, Baltimore, MD, 21287, USA.
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18
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Lauritzen B, Bjelke M, Björkdahl O, Bloem E, Keane K, Kjalke M, Rossen M, Lippert SL, Weldingh KN, Skydsgaard M, Kjellev S. A novel next-generation FVIIIa mimetic, Mim8, has a favorable safety profile and displays potent pharmacodynamic effects: Results from safety studies in cynomolgus monkeys. J Thromb Haemost 2022; 20:1312-1324. [PMID: 35191180 PMCID: PMC9314625 DOI: 10.1111/jth.15682] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Revised: 02/17/2022] [Accepted: 02/18/2022] [Indexed: 11/30/2022]
Abstract
BACKGROUND Mim8 is a novel, next-generation factor VIIIa mimetic in development for subcutaneous prophylactic treatment of patients with hemophilia A with and without inhibitors. In vitro and in vivo models indicate that Mim8 has a distinct hemostatic potential. OBJECTIVES To test the nonclinical safety and pharmacodynamics of Mim8. METHODS The Mim8 nonclinical safety program in cynomolgus monkeys consisted of three studies of 4-26 weeks in duration with Mim8 doses ranging from 0.3-60 mg/kg/week intravenously or subcutaneously. After sacrifice, macroscopic and microscopic pathological examinations were performed. RESULTS Mim8 was well tolerated with no noteworthy clinical observations. No signs of excessive coagulation or pathological macroscopic or microscopic findings were observed at doses 0.3-3 mg/kg/week subcutaneous. Thrombosis-related findings were detected during histopathological examination in a small proportion of animals (16%) receiving doses ranging 6-20 mg/kg/week. Dose-dependent increases in factor X (FX) and factor IX (FIX) concentrations were observed. Shortening of activated partial thromboplastin time (APTT) and increased thrombin generation under ex vivo hemophilia A-like conditions were observed at all Mim8 dose levels. CONCLUSIONS Thrombosis-related findings observed at doses above 6 mg/kg/week Mim8 may have been exaggerated pharmacological reactions to a procoagulant compound in normocoagulant animals. Increases in FX and FIX concentrations could be because of a half-life prolongation due to binding to Mim8, but were limited at clinically relevant exposure levels. Subcutaneous administration of up to 3 mg/kg/week (several fold greater than expected clinical exposure) for 26 weeks resulted in relevant pharmacodynamic effects, observed in thrombin generation and APTT, with no signs of thrombi or excessive coagulation activation.
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Affiliation(s)
| | - Mads Bjelke
- Global Drug DiscoveryNovo Nordisk A/SMåløvDenmark
| | | | - Esther Bloem
- Global Drug DiscoveryNovo Nordisk A/SMåløvDenmark
| | - Kevin Keane
- Global Drug DiscoveryNovo Nordisk A/SMåløvDenmark
| | | | - Marie Rossen
- Global Drug DiscoveryNovo Nordisk A/SMåløvDenmark
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19
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Escuriola Ettingshausen C, Yang R, Wu W, Meeks SL. Inhibitors: Diagnostic challenges, unknowns of inhibitor development, treatment of bleeding and surgery, and insights into diagnosis and treatment in China. Haemophilia 2022; 28 Suppl 4:111-118. [PMID: 35521731 DOI: 10.1111/hae.14553] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2022] [Revised: 03/07/2022] [Accepted: 03/07/2022] [Indexed: 11/30/2022]
Abstract
Factor (F) VIII inhibitors develop in around 30% of previously untreated patients (PUPs) with severe haemophilia, to a lesser extend in moderate and mild haemophilia A and in up to 10% in severe haemophilia B. Diagnostic challenges and questions remain including access to high quality testing, the role for functional inhibitor testing and binding antibody testing, and the adaptations needed in the presence of non-factor replacement therapy. Despite significant gains in knowledge there are still many unanswered questions underlying the immunologic mechanisms of inhibitor development and tolerance. Therapeutic options include eradication of inhibitors using immune tolerance induction therapy (ITI), prophylaxis with bypassing agents (i.e., recombinant activated factor VII /rFVIIa or activated prothrombin complex concentrate/aPCC) or non-factor replacement therapies (e.g., emicizumab) and treatment of bleeds or coverage of surgeries/invasive procedure. Recently a haemophilia centre capacity building program was launched in China to further develop the infrastructure and support needed to improve the diagnosis of haemophilia, detection of inhibitors, and continue to improve the care of patients with haemophilia and inhibitors.
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Affiliation(s)
| | - Renchi Yang
- State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin, China
| | - Wenman Wu
- Department of Laboratory Medicine, Ruijin Hospital affiliated to Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Shannon L Meeks
- Aflac Cancer and Blood Disorders Center of Children's Healthcare of Atlanta and Department of Pediatrics, Emory University, Atlanta, Georgia, USA
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20
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Verhagen MJA, Valke LLFG, Schols SEM. Thrombin generation for monitoring hemostatic therapy in hemophilia A: A narrative review. J Thromb Haemost 2022; 20:794-805. [PMID: 35034413 PMCID: PMC9305107 DOI: 10.1111/jth.15640] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Revised: 12/17/2021] [Accepted: 01/10/2022] [Indexed: 11/29/2022]
Abstract
Patients with severe hemophilia A (HA) have an increased risk of spontaneous and trauma-related bleeding because of a congenital absence of factor VIII (FVIII). Most severe HA patients use prophylactic FVIII concentrate, the effect of which can be monitored with FVIII activity level measurement. However, FVIII activity level is less valuable in predicting the potential clinical bleeding risk. Some patients still experience breakthrough bleeds despite adequate FVIII trough levels, whereas others do not bleed with trough levels below threshold. This difference may be caused by inter-individual differences in pro- and anticoagulant factors, the so-called hemostatic balance. Thrombin generation assays (TGAs) measure the hemostatic balance as a whole. Thereby, the TGAs may be a better tool in the guidance and monitoring of treatment in HA patients. In addition, TGAs offer the opportunity to determine the response to bypassing agents and treatment with non-factor replacement therapy, in which FVIII activity assays are not suitable for monitoring. This review summarizes the current knowledge about monitoring different HA treatment modalities by TGA, as a single treatment option and when used in a concomitant fashion.
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Affiliation(s)
- Marieke J. A. Verhagen
- Department of HematologyRadboud University Medical CenterNijmegenThe Netherlands
- Hemophilia Treatment CenterNijmegen‐Eindhoven‐MaastrichtNijmegenThe Netherlands
| | - Lars L. F. G. Valke
- Department of HematologyRadboud University Medical CenterNijmegenThe Netherlands
- Hemophilia Treatment CenterNijmegen‐Eindhoven‐MaastrichtNijmegenThe Netherlands
| | - Saskia E. M. Schols
- Department of HematologyRadboud University Medical CenterNijmegenThe Netherlands
- Hemophilia Treatment CenterNijmegen‐Eindhoven‐MaastrichtNijmegenThe Netherlands
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21
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Pittman DD, Rakhe S, Bowley SR, Jasuja R, Barakat A, Murphy JE. Hemostatic efficacy of marstacimab alone or in combination with bypassing agents in hemophilia plasmas and a mouse bleeding model. Res Pract Thromb Haemost 2022; 6:e12679. [PMID: 35316941 PMCID: PMC8925002 DOI: 10.1002/rth2.12679] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Accepted: 01/07/2022] [Indexed: 11/06/2022] Open
Abstract
Background Patients with hemophilia have deficiencies in intrinsic coagulation factors and can develop inhibitors that limit the effectiveness of replacement coagulation factors. Marstacimab, a human monoclonal antibody, binds and inhibits the human tissue factor pathway inhibitor. Marstacimab is currently under development as a potential prophylactic treatment to prevent bleeding episodes in patients with hemophilia A and B. Objective To assess the effects of marstacimab alone or in combination with the bypassing agent recombinant factor FVIIa (rFVIIa) or activated prothrombin complex concentrate (aPCC) on thrombin generation and bleeding. Methods Marstacimab and/or rFVIIa or aPCC were added to hemophilic A or B plasma or nonhemophilic plasma in vitro. Hemostatic activity was measured using the thrombin generation assay. In vivo effects were assessed using a mouse acute bleeding model. Male hemophilia A mice were dosed with marstacimab plus aPCC before tail clip; blood loss was quantified by measuring hemoglobin. Results Marstacimab plus rFVIIa or aPCC slightly increased peak thrombin levels compared with either agent alone. This increase was within the reported range for nonhemophilic plasma and did not exceed levels observed in nonhemophilic plasma treated with marstacimab alone. Hemophilia A mice that received 200 U/kg aPCC had significantly reduced bleeding (62%) compared with vehicle‐treated mice (p < 0.05), and marstacimab plus aPCC reduced bleeding by 83.3% compared with vehicle (p= 0.0009). Conclusions Marstacimab alone or with bypassing agents increased hemostasis in hemophilia plasma without generating excessive thrombin. The hemostatic activity of marstacimab plus aPCC was confirmed in hemophilia A mice.
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Affiliation(s)
- Debra D. Pittman
- Rare Disease Research Unit Pfizer Inc. Cambridge Massachusetts USA
| | - Swapnil Rakhe
- Rare Disease Research Unit Pfizer Inc. Cambridge Massachusetts USA
| | - Sheryl R. Bowley
- Rare Disease Research Unit Pfizer Inc. Cambridge Massachusetts USA
| | - Reema Jasuja
- Rare Disease Research Unit Pfizer Inc. Cambridge Massachusetts USA
| | - Amey Barakat
- Rare Disease Research Unit Pfizer Inc. Cambridge Massachusetts USA
| | - John E. Murphy
- Rare Disease Research Unit Pfizer Inc. Cambridge Massachusetts USA
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22
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Jair Lara-Navarro I, Rebeca Jaloma-Cruz A. Current Therapies in Hemophilia: From Plasma-Derived Factor Modalities to CRISPR/Cas Alternatives. TOHOKU J EXP MED 2022; 256:197-207. [DOI: 10.1620/tjem.256.197] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Affiliation(s)
- Irving Jair Lara-Navarro
- División de Genética, Centro de Investigación Biomédica de Occidente, Instituto Mexicano del Seguro Social
| | - Ana Rebeca Jaloma-Cruz
- División de Genética, Centro de Investigación Biomédica de Occidente, Instituto Mexicano del Seguro Social
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23
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Depasse F, Binder NB, Mueller J, Wissel T, Schwers S, Germer M, Hermes B, Turecek PL. Thrombin generation assays are versatile tools in blood coagulation analysis: A review of technical features, and applications from research to laboratory routine. J Thromb Haemost 2021; 19:2907-2917. [PMID: 34525255 PMCID: PMC9291770 DOI: 10.1111/jth.15529] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Revised: 09/07/2021] [Accepted: 09/13/2021] [Indexed: 02/06/2023]
Abstract
Thrombin is the pivotal enzyme in the biochemistry of secondary hemostasis crucial to maintaining homeostasis of hemostasis. In contrast to routine coagulation tests (PT or aPTT) or procoagulant or anticoagulant factor assays (e.g. fibrinogen, factor VIII, antithrombin or protein C), the thrombin generation assay (TGA), also named thrombin generation test (TGT) is a so-called "global assay" that provides a picture of the hemostasis balance though a continuous and simultaneous measurement of thrombin formation and inhibition. First described in the early 1950s, as a manual assay, efforts have been made in order to standardize and automate the assay to offer researchers, clinical laboratories and the pharmaceutical industry a versatile tool covering a wide range of clinical and non-clinical applications. This review describes technical options offered to properly run TGA, including a review of preanalytical and analytical items, performance, interpretation, and applications in physiology research and pharmacy.
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Affiliation(s)
| | - Nikolaus B. Binder
- Technoclone Herstellung von Diagnostika und Arzneimitteln GmbHViennaAustria
| | - Julia Mueller
- Siemens Healthcare Diagnostics Products GmbHMarburgGermany
| | - Thomas Wissel
- Siemens Healthcare Diagnostics Products GmbHMarburgGermany
| | | | | | - Björn Hermes
- DIN e.V. – DIN Standards Committee Medicine (NAMed)BerlinGermany
| | - Peter L. Turecek
- Baxalta Innovations GmbHPart of the Takeda group of companiesViennaAustria
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24
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Schmitt C, Emrich T, Chebon S, Fernandez E, Petry C, Yoneyama K, Kiialainen A, Howard M, Niggli M, Paz-Priel I, Chang T. Low immunogenicity of emicizumab in persons with haemophilia A. Haemophilia 2021; 27:984-992. [PMID: 34480814 PMCID: PMC9292930 DOI: 10.1111/hae.14398] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Revised: 08/13/2021] [Accepted: 08/13/2021] [Indexed: 02/06/2023]
Abstract
INTRODUCTION Emicizumab is a humanised, bispecific monoclonal antibody mimicking the cofactor function of activated factor (F)VIII. It is indicated for routine prophylaxis of bleeding episodes in persons with haemophilia A (PwHA) with/without FVIII inhibitors. AIM To evaluate the development of anti-emicizumab antibodies and their impact on pharmacokinetics (PK), pharmacodynamics (PD), efficacy and safety in PwHA. METHODS Data from seven completed or ongoing phase 3 studies were pooled. The assessment of the immunogenicity profile of emicizumab included anti-drug antibody (ADA) measurement and the association of ADAs with PK, PD, bleeding events, and adverse events. RESULTS Of 668 PwHA evaluable for immunogenicity analysis, 34 (5.1%) developed ADAs after exposure to emicizumab. ADAs were transient in 14/34 PwHA (41.2%). ADAs were neutralising in vitro in 18/34 PwHA (52.9%) and associated with decreased emicizumab concentration in 4/668 evaluable PwHA (.6%); of those, one (.1%) discontinued emicizumab due to loss of efficacy. ADAs without decreased exposure did not impact emicizumab efficacy. The proportion of PwHA who had injection-site reactions (ISRs) was higher in ADA-positive PwHA (29.4% vs. 20.8%); however, the safety profile was similar between ADA-positive and ADA-negative PwHA, overall. No cases of anaphylaxis or hypersensitivity were reported in ADA-positive participants. CONCLUSION The immunogenicity risk of emicizumab in phase 3 studies was low. ADAs, including in vitro neutralising ADAs, were not associated with a change in safety profile. Routine surveillance is, therefore, not warranted; however, in cases where a loss and/or waning of efficacy are observed, prompt evaluation by a healthcare provider should be sought.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | - Ido Paz-Priel
- Genentech, Inc., South San Francisco, California, USA
| | - Tiffany Chang
- Genentech, Inc., South San Francisco, California, USA
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25
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Lockhart M, Tardy-Poncet B, Montmartin A, Noyel P, Thouvenin S, Berger C. Surgery with emicizumab prophylaxis for two paediatric patients with severe haemophilia A with inhibitors. Pediatr Blood Cancer 2021; 68:e29041. [PMID: 33851509 DOI: 10.1002/pbc.29041] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Revised: 03/04/2021] [Accepted: 03/15/2021] [Indexed: 11/07/2022]
Abstract
Emicizumab is a prophylaxis for patients with severe haemophilia A with and without inhibitor. Despite weekly administration of emicizumab, coagulation states stay below normal value and cannot be assessed by standard haemostasis tests. In our two patients, we used the thrombin-generation assay (endogenous thrombin potential and Peak) to monitor the patient's clotting status. Under emicizumab, it is necessary to add a bypassing agent (BPA) such as rFVIIa (Novoseven) to avoid bleeding before surgery. The BPA dosage was based on a thrombin-generation assay and collegial consultation.
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Affiliation(s)
- Marguerite Lockhart
- Hematology and Oncology Pediatric Unit, Haemophilia CRC Hospital of Saint-Etienne, Saint-Etienne, France
| | | | - Aurélie Montmartin
- Inserm U1059, Sainbiose Dysfonction Vasculaire et Hémostase, Université de Lyon, Saint-Etienne, France
| | - Pauline Noyel
- Biology Laboratory University Hospital of Saint-Etienne, Saint-Etienne, France
| | - Sandrine Thouvenin
- Hematology and Oncology Pediatric Unit, Haemophilia CRC Hospital of Saint-Etienne, Saint-Etienne, France
| | - Claire Berger
- Hematology and Oncology Pediatric Unit, Haemophilia CRC Hospital of Saint-Etienne, Saint-Etienne, France.,EA SNA-EPIS 4607, Université Jean Monnet, Saint-Etienne, France
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26
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Schultz NH, Glosli H, Bjørnsen S, Holme PA. The effect of emicizumab and bypassing agents in patients with hemophilia - An in vitro study. Res Pract Thromb Haemost 2021; 5:e12561. [PMID: 34263107 PMCID: PMC8268661 DOI: 10.1002/rth2.12561] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Revised: 05/22/2021] [Accepted: 06/09/2021] [Indexed: 02/03/2023] Open
Abstract
BACKGROUND Emicizumab is a nonfactor replacement therapy for hemophilia A (HA) and is a bispecific monoclonal antibody mimicking factor VIII by binding both factors IXa and X. Although it reduces the frequency of bleeding episodes, there is still need for bypassing agents in case of breakthrough bleeds or need for surgery. The HAVEN-1 study showed an increased risk of thrombotic events and episodes of thrombotic microangiopathic hemolytic anemia with simultaneous treatment with emicizumab and activated prothrombin complex concentrate (aPCC) in high doses (>100 U/kg daily) for more than 1 day, and it is suspected that these drugs have a synergistic hemostatic effect. OBJECTIVES To evaluate and compare the hemostatic effect of bypassing agents in vitro in people with HA before and after starting treatment with emicizumab to investigate if dosing should be adjusted to optimize treatment. PATIENTS/METHODS Blood collected before and after start of treatment with emicizumab was spiked with aPCC and recombinant factor VIIa (rFVIIa) at different concentrations. The effect of aPCC and rFVIIa was assessed by thrombin generation assay and thromboelastometry. RESULTS Six people with HA were included. The response to aPCC in thrombin generation after starting emicizumab was significantly stronger than before. This synergistic effect was less pronounced for emicizumab and rFVIIa. Furthermore, aPCC shortened thromboelastometry clotting time more effectively after starting emicizumab than before starting this treatment. CONCLUSIONS We demonstrated a strong synergistic effect of emicizumab and aPCC and a similar but less pronounced effect of rFVIIa in people treated with emicizumab.
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Affiliation(s)
- Nina Haagenrud Schultz
- Department of HaematologyOslo University HospitalOsloNorway
- Research Institute of Internal MedicineOslo University HospitalOsloNorway
- Department of HaematologyAkershus University HospitalLørenskogNorway
| | - Heidi Glosli
- Division of Paediatric and Adolescent MedicineCentre for Rare DisordersOslo University HospitalOsloNorway
- Division of Paediatric and Adolescent MedicineDepartment of Paediatric ResearchOslo University HospitalOsloNorway
| | - Stine Bjørnsen
- Research Institute of Internal MedicineOslo University HospitalOsloNorway
| | - Pål Andre Holme
- Department of HaematologyOslo University HospitalOsloNorway
- Research Institute of Internal MedicineOslo University HospitalOsloNorway
- Institute of Clinical MedicineUniversity of OsloOsloNorway
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Kjalke M, Kjelgaard‐Hansen M, Andersen S, Hilden I. Thrombin generation potential in the presence of concizumab and rFVIIa, APCC, rFVIII, or rFIX: In vitro and ex vivo analyses. J Thromb Haemost 2021; 19:1687-1696. [PMID: 33819375 PMCID: PMC8360123 DOI: 10.1111/jth.15323] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Revised: 03/03/2021] [Accepted: 03/25/2021] [Indexed: 11/27/2022]
Abstract
BACKGROUND The anti-tissue factor plasma inhibitor monoclonal antibody concizumab is under clinical investigation for subcutaneous prophylaxis of hemophilia A/B (HA/HB) with or without inhibitors. Breakthrough bleeds while on concizumab prophylaxis may be treated with bypassing agents (recombinant activated factor VIIa [rFVIIa] and activated prothrombin complex concentrate [APCC]), or with factor VIII (FVIII) or factor IX (FIX). OBJECTIVES To evaluate the effect of combining concizumab with rFVIIa, APCC, rFVIII, and rFIX on thrombin generation (TG) potential. METHODS Pooled HA plasma was spiked in vitro with concizumab alone or together with rFVIIa, APCC, or rFVIII. rFVIIa, APCC, and rFVIII were added ex vivo to plasma from HA patients receiving concizumab prophylaxis. Pooled HB plasma was spiked with concizumab alone or together with rFIX. TG potential was measured after initiation with tissue factor. RESULTS Concizumab increased thrombin peak in a concentration-dependent manner. Adding rFVIIa, APCC, rFVIII, or rFIX caused a further increase in thrombin peak. The effects of concizumab and rFVIIa, APCC, rFVIII, or rFIX were mainly additive, with no or up to maximally ~25% extra effect caused by drug--drug interaction. No strong synergistic effects were observed upon combining concizumab with rFVIIa, APCC, rFVIII, or rFIX. The thrombin peak obtained with 0.5 IU/ml rFVIII or rFIX in the presence of concizumab was on occasion slightly higher, but mostly comparable to the thrombin peak with 1 IU/ml rFVIII or rFIX in the absence of concizumab. CONCLUSION rFVIIa, APCC, rFVIII, and rFIX enhanced plasma TG potential in the presence of concizumab. Dose levels of concomitant use should be adjusted accordingly to balance potential safety concerns while maintaining the necessary hemostatic effect. Please see the video in the Supplementary Material for an animated summary of the data presented.
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Affiliation(s)
| | | | | | - Ida Hilden
- Global Drug DiscoveryNovo Nordisk A/SMåløvDenmark
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Chowdary P. Nonfactor Therapies: New Approaches to Prophylactic Treatment of Haemophilia. Hamostaseologie 2021; 41:247-256. [PMID: 34187062 DOI: 10.1055/a-1424-7900] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Abstract
For several decades, the treatment of haemophilia has relied on factor replacement therapy, which restores haemostasis by replacing the missing coagulation factor. In recent years, novel alternative therapies for the treatment of haemophilia in patients with and without inhibitors have been developed. These emergent therapies promote haemostasis by mimicking coagulation factors or inhibiting natural anticoagulants. They provide a less invasive route of administration (i.e. subcutaneous) and some offer reduced frequency of dosing (i.e. every 2 weeks, monthly) compared with the majority of factor replacement therapies, and thus have the potential to simplify treatment, increase adherence and subsequently improve outcomes for patients. Their introduction has transformed the care of haemophilia patients with inhibitors to factor VIII, with similar expectation for haemophilia B patients with inhibitors. However, these therapies also come with several new challenges including their limitation to prophylactic treatment, the observed increased incidence of thrombosis, or their impact on the natural history of the disease and potential disruption of existing treatment guidelines like the use of immune tolerance induction. Moreover, questions remain regarding the long-term impact of non-replacement therapies on joint health as well as the optimal strategy to manage breakthrough bleeds in patients with inhibitors.
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Affiliation(s)
- Pratima Chowdary
- Katharine Dormandy Haemophilia and Thrombosis Centre, Royal Free London NHS Foundation Trust, London, United Kingdom
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29
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Abstract
Haemophilia A and B are rare congenital, recessive X-linked disorders caused by lack or deficiency of clotting factor VIII (FVIII) or IX (FIX), respectively. The severity of the disease depends on the reduction of levels of FVIII or FIX, which are determined by the type of the causative mutation in the genes encoding the factors (F8 and F9, respectively). The hallmark clinical characteristic, especially in untreated severe forms, is bleeding (spontaneous or after trauma) into major joints such as ankles, knees and elbows, which can result in the development of arthropathy. Intracranial bleeds and bleeds into internal organs may be life-threatening. The median life expectancy was ~30 years until the 1960s, but improved understanding of the disorder and development of efficacious therapy based on prophylactic replacement of the missing factor has caused a paradigm shift, and today individuals with haemophilia can look forward to a virtually normal life expectancy and quality of life. Nevertheless, the potential development of inhibitory antibodies to infused factor is still a major hurdle to overcome in a substantial proportion of patients. Finally, gene therapy for both types of haemophilia has progressed remarkably and could soon become a reality.
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Kizilocak H, Marquez-Casas E, Malvar J, Carmona R, Young G. Determining the approximate factor VIII level of patients with severe haemophilia A on emicizumab using in vivo global haemostasis assays. Haemophilia 2021; 27:730-735. [PMID: 34115433 DOI: 10.1111/hae.14359] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Revised: 05/14/2021] [Accepted: 06/01/2021] [Indexed: 11/29/2022]
Abstract
INTRODUCTION Emicizumab is a recombinant, humanized bispecific monoclonal antibody that mimics the function of factor VIII (FVIII) which results in a significant reduction in the annualized bleeding rate in patients with haemophilia A (HA), however, the degree with which emicizumab corrects the coagulation defect remains unclear. The objective of this study was to predict the approximate FVIII level in severe haemophilia A patients with inhibitors on emicizumab using global haemostasis assays. MATERIALS AND METHODS Patients with moderate and mild HA in the non-bleeding state and healthy controls had FVIII levels and thrombin generation assessed. Linear regression was utilized to model the FVIII levels as a function of the thrombin generation assay parameters and to make a calibration curve of FVIII levels versus peak thrombin and endogenous thrombin potential. Patients with severe haemophilia A with inhibitors on emicizumab had thrombin generation performed in the same manner and their peak thrombin and endogenous thrombin potential results were placed on the calibration curve to calculate their FVIII Equivalency of Emicizumab by Thrombin Generation (F8EmT). RESULTS All patients with severe HA with inhibitors on emicizumab had F8EmT >10%, suggesting they had been converted to a mild haemophilia phenotype. The patient's weight was inversely correlated to their F8EmT. CONCLUSION The results from this study suggest that the F8EmT in patients with severe HA on emicizumab falls within the range of mild haemophilia which is consistent with the data noted in the emicizumab clinical trials and in vivo studies in animals.
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Affiliation(s)
- Hande Kizilocak
- Children's Hospital Los Angeles, Hemostasis and Thrombosis Center, Los Angeles, California, USA
| | - Elizabeth Marquez-Casas
- Children's Hospital Los Angeles, Hemostasis and Thrombosis Center, Los Angeles, California, USA
| | - Jemily Malvar
- Children's Hospital Los Angeles, Cancer and Blood Disease Institute, Los Angeles, California, USA
| | - Roxana Carmona
- Children's Hospital Los Angeles, Hemostasis and Thrombosis Center, Los Angeles, California, USA
| | - Guy Young
- Children's Hospital Los Angeles, Hemostasis and Thrombosis Center, Los Angeles, California, USA.,Children's Hospital Los Angeles, Cancer and Blood Disease Institute, Los Angeles, California, USA.,Keck School of Medicine, University of Southern California, Los Angeles, California, USA
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31
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Jiménez-Yuste V, Auerswald G, Benson G, Dolan G, Hermans C, Lambert T, Ljung R, Morfini M, Santagostino E, Zupančić Šalek S. Practical considerations for nonfactor-replacement therapies in the treatment of haemophilia with inhibitors. Haemophilia 2021; 27:340-350. [PMID: 33742707 DOI: 10.1111/hae.14167] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Revised: 08/12/2020] [Accepted: 09/11/2020] [Indexed: 12/19/2022]
Abstract
New therapeutic agents for haemophilia with inhibitors that are in development or already licensed are expected to provide transformative treatment options. Many of these new therapies are not based on simply replacing the missing factor; new strategies include bispecific antibody technology that mimics factor VIII coagulation function (emicizumab), and inhibition of anticoagulant proteins such as tissue factor pathway inhibitor (eg PF-06741086) and antithrombin (eg fitusiran). These agents are administered subcutaneously and should significantly reduce treatment burden and increase the ability to deliver prophylaxis for patients. Limited real-world data and validated practical guidance on these recently licensed/upcoming treatments resulted in the authors convening to discuss recommendations on their use. Emicizumab is currently the only licenced nonfactor therapy; thus, our recommendations focus on this product. Target candidates for emicizumab prophylaxis are difficult-to-treat patients with haemophilia A and inhibitors and/or venous access issues, frequent bleeds and target joints. In case of breakthrough bleeding while receiving emicizumab, patients still require treatment with bypassing agents; the adjunct treatment of choice is recombinant activated factor VII. This treatment is also recommended to prevent bleeds in patients with inhibitors undergoing surgery. Our recommendations on suitable laboratory assays and monitoring new products, as well as the benefit of patient-reported outcomes (such as pain and physical activity levels), are included. We also briefly discuss future treatment options for patients with haemophilia B and inhibitors. Although these nonfactor treatments offer great promise, further data and real-world evidence are needed.
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Affiliation(s)
- Victor Jiménez-Yuste
- Hospital Universitario La Paz, Unidad de Coagulopatías, Servicio de Hematología, Autonoma University, Madrid, Spain
| | - Günter Auerswald
- Klinikum Bremen-Mitte, Professor Hess Children's Hospital, Bremen, Germany
| | - Gary Benson
- Haemophilia and Thrombosis Centre, Belfast City Hospital, Belfast, UK
| | - Gerry Dolan
- Centre for Haemostasis and Thrombosis, St Thomas' Hospital, London, UK
| | - Cedric Hermans
- Haemostasis and Thrombosis Unit, Division of Haematology, Cliniques Universitaires Saint-Luc, Brussels, Belgium
| | - Thierry Lambert
- Hemophilia Care Center, Bicêtre AP-HP Hospital and Faculté de Médecine Paris XI, Paris, France
| | - Rolf Ljung
- Department of Clinical Sciences Lund - Paediatrics, Lund University, Lund, Sweden
| | | | - Elena Santagostino
- Fondazione IRCCS Cá Granda, Maggiore Hospital Policlinico, Angelo Bianchi Bonomi Haemophilia and Thrombosis Center, Milan, Italy
| | - Silva Zupančić Šalek
- Unit for Haemostasis, Thrombosis and Benign Diseases of Haematopoietic System, Division of Haematology, Department of Internal Medicine, University Hospital Centre Zagreb, Zagreb, Croatia
- Medical School University of Zagreb, Zagreb, Croatia
- Faculty of Medicine Osijek, J Strossmayer University of Osijek, Osijek, Croatia
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32
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Chamouni P, Barbay V, Billoir P, Le Cam-Duchez V, Malassigne C, Massy N, Königs C. First observation of inhibitor development against efmoroctocog alfa in France. Transfus Apher Sci 2021; 60:103128. [PMID: 33867284 DOI: 10.1016/j.transci.2021.103128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Revised: 03/25/2021] [Accepted: 03/28/2021] [Indexed: 10/21/2022]
Abstract
In patients with severe haemophilia receiving clotting factor concentrates, the risk of immunisation against their usual treatment is still patent and feared. New haemophilia drug treatments with an extended half-life have become available over the past few years. The risk of inhibitor development to these new treatments is unclear. We report the case of a 51-year-old man with severe haemophilia A, who was previously treated with no history of inhibitor development. Soon after a switch in his treatment to efmoroctocog alfa he developed an inhibitor against this recombinant Fc fusion extended half-life FVIII (rFc-FVIII) product. The patient was on an on-demand treatment regimen and was treated for mucosal bleeding. The inhibitor was characterised as type I, with classical epitope mapping. The spontaneous evolution of this inhibitor was favourable, but an anamnestic response led to a switch in his treatment to emicizumab.
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Affiliation(s)
- Pierre Chamouni
- Department of Haematology, Haemophilia Care Centre, Rouen University Hospital, France.
| | - Virginie Barbay
- Department of Haematology, Haemophilia Care Centre, Rouen University Hospital, France
| | - Paul Billoir
- Department of Haematology, Haemophilia Care Centre, Rouen University Hospital, France
| | | | - Céline Malassigne
- Department of Haematology, Haemophilia Care Centre, Rouen University Hospital, France; Department of Haematology, Le Havre Hospital, France
| | - Nathalie Massy
- Department of Pharmacology, Rouen University Hospital, France
| | - Christoph Königs
- Department of Paediatrics, Clinical and Molecular Haemostasis, Frankfurt University Hospital, Frankfurt am Main, Germany
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33
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Dolan G, Astermark J, Hermans C. Recombinant FVIIa in elective non-orthopaedic surgery of adults with haemophilia and inhibitors: A systematic literature review. Haemophilia 2021; 27:e314-e330. [PMID: 33751769 DOI: 10.1111/hae.14291] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Revised: 02/08/2021] [Accepted: 02/22/2021] [Indexed: 11/29/2022]
Abstract
AIM To assess available evidence on the use of rFVIIa in non-orthopaedic surgery including dental surgery in adult patients with congenital haemophilia with inhibitors (PWHI). METHODS A systematic literature search was performed according to a prespecified search string; prespecified criteria were used to select applicable studies including PWHI ≥18 years of age who underwent any non-orthopaedic surgery using rFVIIa. RESULTS Thirty-three publications met the eligibility criteria, of which 26 publications - including 46 procedures in 44 patients - were selected for the qualitative analysis. Most publications were case reports or case series (21/26). Primary authors assessed rFVIIa as effective in maintaining haemostasis during and after most major surgeries (22/32). rFVIIa dose was mainly on label, with higher doses used in 4 cases, and a lower dose in 1 case. Duration of treatment was mostly 5-10 days (range: 3 days to 1 month post-operatively). Adverse events related to rFVIIa were rare. CONCLUSIONS Assessing non-orthopaedic surgery in this patient population is hampered by a paucity of published data; nevertheless, the current evidence indicates that rFVIIa is effective in achieving haemostasis in haemophilia patients with inhibitors undergoing elective non-orthopaedic or dental surgery. rFVIIa was generally well tolerated in these patients, with thrombotic events occurring rarely. These data, generated to help clinicians manage congenital haemophilia with inhibitors, highlight the need for more systematic reporting of rFVIIa and all other therapeutic agents in non-orthopaedic surgery and dental surgery in patients with congenital haemophilia and inhibitors.
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Affiliation(s)
| | - Jan Astermark
- Department of Translational Medicine, Lund University, Malmö, Sweden.,Department of Hematology, Oncology and Radiation Physics, Skåne University Hospital, Malmö, Sweden
| | - Cedric Hermans
- Haemostasis and Thrombosis Unit, Division of Haematology, Haemophilia Centre, dCliniques universitaires Saint-Luc, Université catholique de Louvain, Brussels, Belgium
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34
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A hemophilia A mouse model for the in vivo assessment of emicizumab function. Blood 2021; 136:740-748. [PMID: 32369559 DOI: 10.1182/blood.2019004334] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Accepted: 04/12/2020] [Indexed: 11/20/2022] Open
Abstract
The bispecific antibody emicizumab is increasingly used for hemophilia A treatment. However, its specificity for human factors IX and X (FIX and FX) has limited its in vivo functional analysis to primate models of acquired hemophilia. Here, we describe a novel mouse model that allows emicizumab function to be examined. Briefly, FVIII-deficient mice received IV emicizumab 24 hours before tail-clip bleeding was performed. A second infusion with human FIX and FX, administered 5 minutes before bleeding, generated consistent levels of emicizumab (0.7-19 mg/dL for 0.5-10 mg/kg doses) and of both FIX and FX (85 and 101 U/dL, respectively, after dosing at 100 U/kg). Plasma from these mice display FVIII-like activity in assays (diluted activated partial thromboplastin time and thrombin generation), similar to human samples containing emicizumab. Emicizumab doses of 1.5 mg/kg and higher significantly reduced blood loss in a tail-clip-bleeding model using FVIII-deficient mice. However, reduction was incomplete compared with mice treated with human FVIII concentrate, and no difference in efficacy between doses was observed. From this model, we deducted FVIII-like activity from emicizumab that corresponded to a dose of 4.5 U of FVIII per kilogram (ie, 9.0 U/dL). Interestingly, combined with a low FVIII dose (5 U/kg), emicizumab provided enough additive activity to allow complete bleeding arrest. This model could be useful for further in vivo analysis of emicizumab.
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35
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Wang CP, Young G, Thornburg CD. Safety evaluation of emicizumab prophylaxis in individuals with haemophilia A. Expert Opin Drug Saf 2021; 20:387-396. [PMID: 33612049 DOI: 10.1080/14740338.2021.1893303] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
INTRODUCTION Emicizumab is a bispecific-humanized monoclonal antibody that improves hemostasis by bridging activated factor IX and factor X to substitute for the function of missing activated FVIII. It is an alternative to prophylaxis with factor VIII replacement and is associated with improved outcomes in individuals with hemophilia A with and without inhibitors. AREAS COVERED Emicizumab is efficacious in reducing bleeding events when compared to on-demand treatment and factor-based prophylaxis. Except for the few thrombotic microangiopathy and thrombotic event cases mainly seen in the HAVEN 1 trial, emicizumab has an overall excellent safety profile with minimal side effects. EXPERT OPINION Knowledge gaps include the efficacy and safety of emicizumab in younger age groups and those with mild or moderate hemophilia A. Future directions for research include exploring the risk of inhibitor recurrence in patients with a history of high titer inhibitor who have been successfully tolerized, who switch from factor prophylaxis to emicizumab, as well as conducting 'real world studies' to evaluate the patient's perception of emicizumab in regard to ease and tolerability in order to optimize individualized treatment plans.
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Affiliation(s)
- Cassandra P Wang
- Department of Pediatrics, University of California-San Diego School of Medicine, La Jolla, CA, USA
| | - Guy Young
- Division of Pediatric Hematology/Oncology, Children's Hospital Los Angeles/University of Southern California Keck School of Medicine, Los Angeles, CA, USA
| | - Courtney D Thornburg
- Division of Pediatric Hematology/Oncology, Rady Children's Hospital San Diego/University of California, San Diego, CA, USA
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36
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Grandoni J, Duretz V, Bonzo D, Evans S, Plantier JL. Exploratory in vitro evaluation of thrombin generation of eptacog beta (recombinant human fviia) and emicizumab in congenital haemophilia A plasma. Haemophilia 2021; 27:321-328. [PMID: 33550714 PMCID: PMC8048629 DOI: 10.1111/hae.14253] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Revised: 11/22/2020] [Accepted: 12/24/2020] [Indexed: 01/11/2023]
Abstract
Introduction/Aim Eptacog beta is a recombinant activated human factor VII approved to treat and control bleeding in haemophilia A and B patients with inhibitors. Emicizumab is a factor VIIIa mimetic antibody approved for prophylactic treatment of haemophilia A with and without inhibitors (HAI and HA, respectively). Inhibitor patients treated with emicizumab should expect breakthrough bleeding that requires bypassing agent treatment to restore haemostasis. The aim of this study is to quantify the in vitro thrombin generation induced by the addition of eptacog beta to HAI and HA plasma containing emicizumab. Methods Thrombin generation assays were performed using HAI and HA plasma. Thrombin generation parameters were examined using a fixed effects model with inhibitor titre, eptacog beta concentration and emicizumab concentration as main effects, and eptacog beta concentration with inhibitor and emicizumab concentration with inhibitor as interaction effects. Results A significant increase in peak thrombin, ETP and velocity was observed when combinations of eptacog beta (0, 1, 2 or 5 µg/ml) and emicizumab (0, 50 or 100 µg/ml) were evaluated in HA and HAI plasma; the effect remained below that observed in Normal Plasma (NP). A small shortening of lag time below that of NP was observed. Conclusions Eptacog beta and emicizumab induced thrombin generation in haemophilia A plasma (with and without inhibitors) with the thrombin generation parameters remaining below those of normal plasma. These data provide in vitro proof of concept supporting the concept of use of eptacog beta for the treatment and control of breakthrough bleeding in patients on emicizumab prophylaxis.
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Affiliation(s)
- Jerry Grandoni
- LFB USA, Framingham, MA, USA.,Allena Pharmaceuticals, Sudbury, MA, USA
| | - Véronique Duretz
- LFB Biotechnologies, Les Ulis, France.,LFB Biomédicaments, Lille, France
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37
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Croteau SE, Wang M, Wheeler AP. 2021 clinical trials update: Innovations in hemophilia therapy. Am J Hematol 2021; 96:128-144. [PMID: 33064330 DOI: 10.1002/ajh.26018] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Revised: 10/07/2020] [Accepted: 10/12/2020] [Indexed: 01/19/2023]
Abstract
Therapies engineered to prolong clotting factor protein circulation time, manipulate the balance of pro-coagulant and anti-coagulant proteins, or introduce new genetic material to enable endogenous factor protein production dominate the clinical trial landscape of hemophilia. The availability of clotting factor concentrates and the establishment of primary prophylaxis have dramatically improved health outcomes for hemophilia patients. But, the burden of hemostatic therapy remains significant, and many barriers to consistent longitudinal use of prophylaxis exist. Several types of emerging therapeutics including engineered factor concentrates, substitutive therapies, rebalancing therapies, and gene transfer/editing all aim to reduce the challenges of current hemophilia treatment. Emerging treatment options may reduce treatment frequency or need for intravenous administration. They may also introduce new challenges in laboratory assessment of hemostasis. These novel therapies must not introduce significant new health risks and continue to support similar or improved outcomes. The potential ramifications of rebalancing the coagulation cascade, particularly in a stress or inflammatory state, or introduction of new genetic material are not trivial. The focus of this review is to provide an overview of active and recently completed clinical trials as well as emerging preclinical data investigating new therapeutic possibilities for hemophilia patients and potentially other rare bleeding disorders.
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Affiliation(s)
| | - Michael Wang
- University of Colorado Hemophilia and Thrombosis Center Aurora Colorado
| | - Allison P. Wheeler
- Department of Pathology, Microbiology & Immunology Vanderbilt University Medical Center Nashville Tennessee
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38
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Brackmann HH, Schramm W, Oldenburg J, Cano V, Turecek PL, Négrier C. Origins, Development, Current Challenges and Future Directions with Activated Prothrombin Complex Concentrate for the Treatment of Patients with Congenital Haemophilia with Inhibitors. Hamostaseologie 2020; 40:606-620. [PMID: 32717751 PMCID: PMC7772007 DOI: 10.1055/a-1159-4273] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Accepted: 04/16/2020] [Indexed: 12/17/2022] Open
Abstract
Congenital haemophilia A (HA) is caused by deficiency of coagulation factor VIII (FVIII) activity, leading to spontaneous or traumatic bleeding events. While FVIII replacement therapy can treat and prevent bleeds, approximately 30% of patients with severe HA develop inhibitor antibodies that render FVIII replacement therapy ineffective. The bypassing agents (BPAs), activated prothrombin complex concentrate (aPCC) and recombinant activated FVII, first approved in 1977 and 1996, respectively, act to generate thrombin independent of pathways that involve factors IX and VIII. Both may be used in patients with congenital haemophilia and inhibitors (PwHIs) for the treatment and prevention of acute bleeds and quickly became standard of care. However, individual patients respond differently to different agents. While both agents are approved for on-demand treatment and perioperative management for patients with congenital haemophilia with inhibitors, aPCC is currently the only BPA approved worldwide for prophylaxis in PwHI. Non-factor therapies (NFTs) have a mechanism of action distinct from BPAs and have reported higher efficacy rates as prophylactic regimens. Nonetheless, treatment challenges remain with NFTs, particularly regarding the potential for synergistic action on thrombin generation with concomitant use of other haemostatic agents, such as BPAs, for the treatment of breakthrough bleeds and in perioperative management. Concomitant use of NFTs with other haemostatic agents could increase the risk of adverse events such as thromboembolic events or thrombotic microangiopathy. This review focuses on the origins, development and on-going role of aPCC in the evolving treatment landscape in the management of PwHI.
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Affiliation(s)
- Hans H. Brackmann
- Haemophilia Center, Institute of Experimental Haematology and Blood Transfusion, University of Bonn, Bonn, Germany
| | - Wolfgang Schramm
- Rudolf Marx-Stiftung für Hämostaseologie, Universität München and Bluterbetreuung Bayern e. V. (BBB) - Germany
| | - Johannes Oldenburg
- Haemophilia Center, Institute of Experimental Haematology and Blood Transfusion, University of Bonn, Bonn, Germany
| | - Viridiana Cano
- Shire International GmbH, a Takeda company, Zürich, Switzerland
| | | | - Claude Négrier
- Haemophilia and Thrombosis Centre, Louis Pradel Hospital, University Claude Bernard Lyon 1, Lyon, France
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39
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Kizilocak H, Marquez-Casas E, Phei Wee C, Malvar J, Carmona R, Young G. Comparison of bypassing agents in patients on emicizumab using global hemostasis assays. Haemophilia 2020; 27:164-172. [PMID: 33245833 DOI: 10.1111/hae.14213] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Revised: 10/23/2020] [Accepted: 11/09/2020] [Indexed: 12/19/2022]
Abstract
INTRODUCTION Emicizumab is a humanized bispecific monoclonal antibody licensed for patients with severe haemophilia A with and without inhibitors. Management of breakthrough bleeding in patients with inhibitors on emicizumab involves episodic treatment with bypassing agents (BPA), activated prothrombin complex concentrate (aPCC) or recombinant activated factor VII (rFVIIa). Thrombotic events and thrombotic microangiopathy were reported when patients on emicizumab received concomitant aPCC at relatively high doses yet such events were not reported with rFVIIa. We studied the effect of spiking various concentrations of BPA on plasma taken from patients on emicizumab. MATERIAL AND METHODS Eleven patients with severe haemophilia A with inhibitors who are on emicizumab were recruited to participate. Blood samples drawn from patients were spiked in vitro with varying concentrations of aPCC and rFVIIa. All samples were tested utilizing global haemostasis assays, thromboelastography and thrombin generation assay. RESULTS Thrombin generation increased with higher concentrations of spiked BPA with a normalized endogenous thrombin potential at a concentration of 0.05 IU/ml and 4 mcg/ml for aPCC and rFVIIa, respectively. Concentrations of aPCC in the range of licensed dosing led to excessive thrombin generation. Thromboelastography was not sufficiently sensitive. CONCLUSION Due to the known thrombotic complications when emicizumab is used in conjunction with aPCC, there has been a large-scale abandonment of the use of aPCC in patients on emicizumab. However, it is possible that aPCC can be used safely with emicizumab albeit with lower doses than are typically prescribed. It would be important to test this hypothesis in a clinical study.
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Affiliation(s)
- Hande Kizilocak
- Hemostasis and Thrombosis Center, Children's Hospital Los Angeles, Los Angeles, CA, USA
| | | | - Choo Phei Wee
- Saban Research Institute, Biostatistics Core, Children's Hospital Los Angeles, Los Angeles, CA, USA
| | - Jemily Malvar
- Cancer and Blood Disease Institute, Children's Hospital Los Angeles, Los Angeles, CA, USA
| | - Roxana Carmona
- Hemostasis and Thrombosis Center, Children's Hospital Los Angeles, Los Angeles, CA, USA
| | - Guy Young
- Hemostasis and Thrombosis Center, Children's Hospital Los Angeles, Los Angeles, CA, USA.,Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
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40
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Escuriola-Ettingshausen C, Auerswald G, Königs C, Kurnik K, Scholz U, Klamroth R, Oldenburg J. Optimizing the management of patients with haemophilia A and inhibitors in the era of emicizumab: Recommendations from a German expert panel. Haemophilia 2020; 27:e305-e313. [PMID: 32937002 DOI: 10.1111/hae.14010] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Revised: 04/02/2020] [Accepted: 04/06/2020] [Indexed: 12/14/2022]
Abstract
Standard treatment of haemophilia A is based on replacing the missing coagulation factor VIII (FVIII) to treat and prevent bleeding episodes. The most challenging complication of FVIII therapy is the development of neutralizing antibodies (inhibitors) that can render treatment ineffective. Eradication of the inhibitor through immune tolerance induction (ITI) remains the most effective strategy for managing these patients. Bypassing agents can be used to help restore haemostasis in inhibitor patients. Several novel agents have recently been developed, such as the FVIII mimetic agent emicizumab, which has been effective in reducing the annualized bleeding rate in haemophilia A patients with inhibitors. When coadministered with repetitive high doses of activated prothrombin complex concentrate (ie >100 U/kg/d for ≥24 hours), emicizumab was associated with thrombotic microangiopathy and thrombosis events. As a consequence the United Kingdom Haemophilia Centres Doctors' Organisation (UKHCDO) issued the first guidance on the treatment of bleeding episodes in patients receiving emicizumab. To build on and extend this work, a panel of German haemophilia specialists met to discuss the UK guidance, review current evidence and provide additional guidance for German healthcare professionals on how to optimize the management of patients with haemophilia A receiving emicizumab. Recommendations are provided on the use of bypassing and other agents to manage breakthrough bleeding, ITI in the emicizumab era, haemostatic support during surgery and issues relating to laboratory monitoring.
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Affiliation(s)
| | - Günter Auerswald
- Department of Comprehensive Care in Haemostasis and Thrombosis, Professor Hess Children's Hospital, Bremen, Germany
| | - Christoph Königs
- Department of Pediatrics and Adolescent Medicine, Centre for Hemostasis, University Hospital Frankfurt, Frankfurt, Germany
| | - Karin Kurnik
- Department of Paediatric Haemostasis, University Children's Hospital, Munich, Germany
| | | | - Robert Klamroth
- Department for Internal Medicine, Vascular Medicine and Haemostaseology, Vivantes Klinikum, Berlin, Germany
| | - Johannes Oldenburg
- Institute of Experimental Hematology and Transfusion Medicine, University Clinic Bonn, Bonn, Germany
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41
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Nougier C, Jeanpierre E, Ternisien C, Proulle V, Hezard N, Pouplard C, Lasne D. Emicizumab treatment: Impact on coagulation tests and biological monitoring of haemostasis according to clinical situations (BIMHO group proposals). Eur J Haematol 2020; 105:675-681. [PMID: 32668090 DOI: 10.1111/ejh.13490] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Revised: 07/08/2020] [Accepted: 07/09/2020] [Indexed: 02/05/2023]
Abstract
Emicizumab, a bispecific humanised monoclonal antibody restoring to some extent the function of activated FVIII deficient in haemophilia A, represents a major therapeutic advance in the management of haemophilia A patients. No dosage adjustment is required, which leads to a major change for patients used to regular biological monitoring which is particularly burdensome in the case of substitution therapy. In some circumstances, such as before an invasive procedure or in case of bleeding, biological monitoring will be necessary and emicizumab's interference with haemostasis tests, particularly those based on an activated partial thromboplastin times (aPTT), must be known to best interpret the tests and to select the most appropriate methods to guide therapy. The normalisation of aPTT in patients treated with emicizumab is not sufficient to consider haemostasis as normalised. In the event of administration of FVIII to a patient receiving emicizumab, the determination of FVIII should use a chromogenic method using non-human reagents. Coagulation global tests have been proposed to evaluate the biological response when using bypassing agents in patients treated with emicizumab, but the usefulness must be confirmed. The French group BIMHO presents proposals for biological monitoring of a patient treated with emicizumab according to clinical situations.
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Affiliation(s)
- Christophe Nougier
- Laboratoire d'hématologie-hémostase, Centre de Biologie et Pathologie Est, Hospices civils de Lyon, Bron, France
| | | | | | - Valérie Proulle
- Service d'Hématologie Biologique, CHU Bicètre, AP-HP, Université Paris Sud Saclay, INSERM U1176, Le Kremlin-Bicêtre, France
| | - Nathalie Hezard
- Laboratoire d'hématologie, Hôpitaux de Marseille, Marseille, France
| | - Claire Pouplard
- Service d'Hématologie Hémostase, Hôpital Trousseau, CHU de Tours, EA 7501 Université François Rabelais, Tours, France
| | - Dominique Lasne
- Laboratoire d'hématologie générale, Hôpital Necker, AP-HP, Paris, France.,Université Paris Sud Paris Saclay, Inserm U1176, Le Kremlin-Bicêtre, France
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42
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Bravo MI, Raventós A, Pérez A, Costa M, Willis T. Non-additive effect on thrombin generation when a plasma-derived factor VIII/von Willebrand factor (FVIII/VWF) is combined with emicizumab in vitro. J Thromb Haemost 2020; 18:1934-1939. [PMID: 32379931 DOI: 10.1111/jth.14887] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Revised: 04/22/2020] [Accepted: 04/29/2020] [Indexed: 12/12/2022]
Abstract
BACKGROUND Emicizumab is an alternative non-factor approach for treating patients with hemophilia A. However, there is a potential risk of thrombotic events when emicizumab is concomitantly administered with pro-hemostatic therapies. OBJECTIVES To assess the hemostatic effect in vitro when a plasma-derived factor VIII concentrate containing von Willebrand factor (pdFVIII/VWF) was added to hemophilia A plasma (HAp) in combination with emicizumab. METHODS HAp and HAp with FVIII inhibitors (HAp-i) samples with different concentrations of emicizumab (50 and 100 μg/mL) were combined with activated prothrombin complex concentrate at 0.5 to 1 U/mL, recombinant activated factor VII (rFVIIa) at 0.5 to 7 μg/mL, and pdFVIII/VWF at 0.1 to 4.5 IU/mL. Thrombin generation (TG; thrombin peak and endogenous thrombin potential) was determined using a Calibrated Automated Thrombogram assay. RESULTS When activated prothrombin complex concentrate was added to HAp and HAp-i with emicizumab, TG dramatically increased (multiplier effect > 4.5×). Addition of rFVIIa to HAp or HAp-i with emicizumab moderately increased TG in a concentration-related manner compared with rFVIIa alone. Addition of pdFVIII/VWF to HAp or HAp-i with emicizumab induced a TG response equivalent to those samples without emicizumab. In an in vitro model of immune tolerance induction with bleeds (HAp-i 15 Bethesda units), combination of pdFVIII/VWF, emicizumab, and rFVIIa did not trigger a multiplying effect on TG. CONCLUSIONS pdFVIII/VWF showed a non-additive effect on TG when combined in vitro with emicizumab. This finding suggests that emicizumab has limited ability to promote factor X activation in the presence of pdFVIII/VWF, thus reducing the risk of thrombotic events.
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Affiliation(s)
| | - Aida Raventós
- Bioscience Research Group, Grifols, Barcelona, Spain
| | - Alba Pérez
- Bioscience Research Group, Grifols, Barcelona, Spain
| | | | - Todd Willis
- Bioscience Research Group, Grifols, Raleigh, NC, USA
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43
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Gelbenegger G, Schoergenhofer C, Knoebl P, Jilma B. Bridging the Missing Link with Emicizumab: A Bispecific Antibody for Treatment of Hemophilia A. Thromb Haemost 2020; 120:1357-1370. [PMID: 32717759 PMCID: PMC7649063 DOI: 10.1055/s-0040-1714279] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Hemophilia A, characterized by absent or ineffective coagulation factor VIII (FVIII), is a serious bleeding disorder that entails severe and potentially life-threatening bleeding events. Current standard therapy still involves replacement of FVIII, but is often complicated by the occurrence of neutralizing alloantibodies (inhibitors). Management of patients with inhibitors is challenging and necessitates immune tolerance induction for inhibitor eradication and the use of bypassing agents (activated prothrombin complex concentrates or recombinant activated factor VII), which are expensive and not always effective. Emicizumab is the first humanized bispecific monoclonal therapeutic antibody designed to replace the hemostatic function of activated FVIII by bridging activated factor IX and factor X (FX) to activate FX and allow the coagulation cascade to continue. In the majority of hemophilic patients with and without inhibitors, emicizumab reduced the annualized bleeding rate to almost zero in several clinical trials and demonstrated a good safety profile. However, the concurrent use of emicizumab and activated prothrombin complex concentrate imposes a high risk of thrombotic microangiopathy and thromboembolic events on patients and should be avoided. Yet, the management of breakthrough bleeds and surgery remains challenging with only limited evidence-based recommendations being available. This review summarizes published clinical trials and preliminary reports of emicizumab and discusses the clinical implications of emicizumab in treatment of hemophilia A.
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Affiliation(s)
- Georg Gelbenegger
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
| | | | - Paul Knoebl
- Division of Hematology, Department of Internal Medicine I, Medical University of Vienna, Vienna, Austria
| | - Bernd Jilma
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
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44
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Zong Y, Antovic A, Soutari NMH, Antovic J, Pruner I. Synergistic Effect of Bypassing Agents and Sequence Identical Analogue of Emicizumab and Fibrin Clot Structure in the In Vitro Model of Hemophilia A. TH OPEN 2020; 4:e94-e103. [PMID: 32704613 PMCID: PMC7373667 DOI: 10.1055/s-0040-1710032] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2019] [Accepted: 03/24/2020] [Indexed: 02/02/2023] Open
Abstract
Development of inhibitors to factor VIII (FVIII) occurs in approximately 30% of severe hemophilia A (HA) patients. These patients are treated with bypassing agents (activated prothrombin complex concentrate [aPCC] and recombinant activated FVII-rFVIIa). Recently, a bispecific FIX/FIXa- and FX/FXa-directed antibody (emicizumab) has been approved for the treatment of HA patients with inhibitors. However, the data from clinical studies imply that coadministration of emicizumab and bypassing agents, especially aPCC, could have a thrombotic effect. This study was aimed to address the question of potential hypercoagulability of emicizumab and bypassing agents' coadministration, we have investigated fibrin clot formation and structure in the in vitro model of severe HA after adding sequence-identical analogue (SIA) of emicizumab and bypassing agents. Combined overall hemostasis potential (OHP) and fibrin clot turbidity assay was performed in FVIII-deficient plasma after addition of different concentrations of SIA, rFVIIa, and aPCC. Pooled normal plasma was used as control. The fibrin clots were analyzed by scanning electron microscopy (SEM). OHP and turbidity parameters improved with the addition of aPCC, while therapeutic concentrations of rFVIIa did not show substantial improvement. SIA alone and in combination with rFVIIa or low aPCC concentration improved OHP and turbidity parameters and stabilized fibrin network, while in combination with higher concentrations of aPCC expressed hypercoagulable pattern and generated denser clots. Our in vitro model suggests that combination of SIA and aPCC could potentially be prothrombotic, due to hypercoagulable changes in fibrin clot turbidity and morphology. Additionally, combination of SIA and rFVIIa leads to the formation of stable clots similar to normal fibrin clots.
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Affiliation(s)
- Yanan Zong
- Department of Molecular Medicine and Surgery, Clinical Chemistry and Coagulation, Karolinska Institutet, Stockholm, Sweden
| | - Aleksandra Antovic
- Department of Medicine, Unit of Rheumatology, Karolinska Institutet and Academic Specialist Center, Center for Rheumatology, Stockholm Health Services, Stockholm, Sweden
| | - Nida Mahmoud Hourani Soutari
- Department of Molecular Medicine and Surgery, Clinical Chemistry and Coagulation, Karolinska Institutet, Stockholm, Sweden.,Department of Clinical Chemistry, Karolinska University Hospital, Stockholm, Sweden
| | - Jovan Antovic
- Department of Molecular Medicine and Surgery, Clinical Chemistry and Coagulation, Karolinska Institutet, Stockholm, Sweden.,Department of Clinical Chemistry, Karolinska University Hospital, Stockholm, Sweden
| | - Iva Pruner
- Department of Molecular Medicine and Surgery, Clinical Chemistry and Coagulation, Karolinska Institutet, Stockholm, Sweden
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45
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Butterfield JSS, Hege KM, Herzog RW, Kaczmarek R. A Molecular Revolution in the Treatment of Hemophilia. Mol Ther 2020; 28:997-1015. [PMID: 31843450 PMCID: PMC7132613 DOI: 10.1016/j.ymthe.2019.11.006] [Citation(s) in RCA: 65] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Revised: 10/31/2019] [Accepted: 11/05/2019] [Indexed: 12/15/2022] Open
Abstract
For decades, the monogenetic bleeding disorders hemophilia A and B (coagulation factor VIII and IX deficiency) have been treated with systemic protein replacement therapy. Now, diverse molecular medicines, ranging from antibody to gene to RNA therapy, are transforming treatment. Traditional replacement therapy requires twice to thrice weekly intravenous infusions of factor. While extended half-life products may reduce the frequency of injections, patients continue to face a lifelong burden of the therapy, suboptimal protection from bleeding and joint damage, and potential development of neutralizing anti-drug antibodies (inhibitors) that require less efficacious bypassing agents and further reduce quality of life. Novel non-replacement and gene therapies aim to address these remaining issues. A recently approved factor VIII-mimetic antibody accomplishes hemostatic correction in patients both with and without inhibitors. Antibodies against tissue factor pathway inhibitor (TFPI) and antithrombin-specific small interfering RNA (siRNA) target natural anticoagulant pathways to rebalance hemostasis. Adeno-associated virus (AAV) gene therapy provides lasting clotting factor replacement and can also be used to induce immune tolerance. Multiple gene-editing techniques are under clinical or preclinical investigation. Here, we provide a comprehensive overview of these approaches, explain how they differ from standard therapies, and predict how the hemophilia treatment landscape will be reshaped.
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Affiliation(s)
| | - Kerry M Hege
- Department of Pediatrics, Indiana University School of Medicine, IUPUI-Wells Center for Pediatric Research, Indianapolis, IN, USA
| | - Roland W Herzog
- Department of Pediatrics, University of Florida, Gainesville, FL, USA; Department of Pediatrics, Indiana University School of Medicine, IUPUI-Wells Center for Pediatric Research, Indianapolis, IN, USA.
| | - Radoslaw Kaczmarek
- Department of Pediatrics, Indiana University School of Medicine, IUPUI-Wells Center for Pediatric Research, Indianapolis, IN, USA; Laboratory of Glycobiology, Hirszfeld Institute of Immunology and Experimental Therapy, Wroclaw, Poland.
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46
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Le Quellec S. Clinical Evidence and Safety Profile of Emicizumab for the Management of Children with Hemophilia A. DRUG DESIGN DEVELOPMENT AND THERAPY 2020; 14:469-481. [PMID: 32099331 PMCID: PMC7007498 DOI: 10.2147/dddt.s167731] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/17/2019] [Accepted: 01/22/2020] [Indexed: 01/03/2023]
Abstract
Emicizumab is a bispecific, humanized, monoclonal antibody mimicking the factor (F) VIII cofactor activity in mediating the generation of FXa by FIXa in patients with hemophilia A (HA). This subcutaneous non-factor agent has been recently extensively approved for the prophylaxis of patients of HA patients with and without FVIII-inhibitors of all ages, although few data are currently available in children. In Phase 3 clinical trials and case series, emicizumab prophylaxis significantly reduced bleeding rates compared to previous treatment in HA adolescents and children with or without FVIII-inhibitors and was generally well tolerated. In addition, subcutaneous administration of emicizumab provided beneficial effects on health-related quality of life, and lessened the burden of the disease in HA patients as well as in their caregivers. However, additional prospective studies are required to evaluate the long-term safety of emicizumab prophylaxis in very young patients, including previously untreated patients. The aim of this paper was to review the limited data available on the use of emicizumab prophylaxis in children and to highlight the need for further studies to address remaining concerns.
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Affiliation(s)
- Sandra Le Quellec
- Unité d'hémostase Clinique - Hôpital Cardiologique Louis Pradel - Hospices Civils de Lyon, Lyon, France.,Service d'hématologie biologique, Groupement Hospitalier Est - Hospices Civils de Lyon, Lyon, France
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47
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Meeks SL, Leissinger CA. The evolution of factor VIIa in the treatment of bleeding in haemophilia with inhibitors. Haemophilia 2019; 25:911-918. [PMID: 31489759 PMCID: PMC6899648 DOI: 10.1111/hae.13845] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Revised: 08/07/2019] [Accepted: 08/19/2019] [Indexed: 01/19/2023]
Abstract
The use of activated factor VII (FVIIa) for the treatment of bleeding events in haemophilia patients with inhibitors was first reported over 30 years ago. Since then clinical trials, registries, case series, real‐world experience and an understanding of its mechanism of action have transformed what was originally a scientific curiosity into one of the major treatments for inhibitor patients, with innovative therapeutic regimens, dose optimization and individualized care now widely practiced. Given current understanding and use, it might be easy to forget the years of clinical research that led up to this point; in this review, we lay out changes based on broad eras of rFVIIa use. These eras cover the original uncertainty associated with dosing, efficacy and safety; the transformation of care ushered in with its widespread use; and the optimization and individualization of patient care and the importance of specialized support provided by haemophilia treatment centres. Today with the introduction of novel prophylactic agents such as emicizumab, we once again find ourselves dealing with the uncertainties of how best to utilize rFVIIa and newer investigational variants such as marzeptacog alfa and eptacog beta; we hope that the experiences of the past three decades will serve as a guide for this new era of care.
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Affiliation(s)
- Shannon L Meeks
- Department of Pediatrics, Aflac Cancer and Blood Disorders Center at Children's Healthcare of Atlanta, Emory University School of Medicine, Atlanta, GA, USA
| | - Cindy A Leissinger
- Section of Hematology/Oncology, Tulane University School of Medicine, New Orleans, LA, USA
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48
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Batsuli G, Zimowski KL, Tickle K, Meeks SL, Sidonio RF. Immune tolerance induction in paediatric patients with haemophilia A and inhibitors receiving emicizumab prophylaxis. Haemophilia 2019; 25:789-796. [DOI: 10.1111/hae.13819] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Revised: 06/17/2019] [Accepted: 06/17/2019] [Indexed: 12/23/2022]
Affiliation(s)
- Glaivy Batsuli
- Aflac Cancer and Blood Disorders Center of Children’s Healthcare of Atlanta, Department of Pediatrics Emory University Atlanta Georgia
| | - Karen L. Zimowski
- Aflac Cancer and Blood Disorders Center of Children’s Healthcare of Atlanta, Department of Pediatrics Emory University Atlanta Georgia
| | - Kelly Tickle
- Aflac Cancer and Blood Disorders Center of Children’s Healthcare of Atlanta Atlanta Georgia
| | - Shannon L. Meeks
- Aflac Cancer and Blood Disorders Center of Children’s Healthcare of Atlanta, Department of Pediatrics Emory University Atlanta Georgia
| | - Robert F. Sidonio
- Aflac Cancer and Blood Disorders Center of Children’s Healthcare of Atlanta, Department of Pediatrics Emory University Atlanta Georgia
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49
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Susen S, Gruel Y, Godier A, Harroche A, Chambost H, Lasne D, Rauch A, Roullet S, Fontana P, Goudemand J, de Maistre E, Chamouard V, Wibaut B, Albaladejo P, Négrier C. Management of bleeding and invasive procedures in haemophilia A patients with inhibitor treated with emicizumab (Hemlibra ® ): Proposals from the French network on inherited bleeding disorders (MHEMO), the French Reference Centre on Haemophilia, in collaboration with the French Working Group on Perioperative Haemostasis (GIHP). Haemophilia 2019; 25:731-737. [PMID: 31294904 DOI: 10.1111/hae.13817] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Revised: 06/13/2019] [Accepted: 06/14/2019] [Indexed: 02/06/2023]
Abstract
INTRODUCTION Emicizumab (Hemlibra® ) recently became available and requires an adaptation for managing bleeding, suspected bleeding and emergency or scheduled invasive procedures in haemophilia A patients with inhibitor. This implicates a multidisciplinary approach and redaction of recommendations for care that must be regularly adapted to the available data. AIM The following text aims to provide a guide for the management of people with haemophilia A with inhibitor treated with emicizumab in case of bleeding or invasives procedures. METHODS The French network on inherited bleeding disorders (MHEMO), the French Reference Centre on Haemophilia (CRH), in collaboration with the French Working Group on Perioperative Haemostasis (GIHP) have been working together to make proposals for the management of these situations. RESULTS Haemostatic treatment and other medications should be given stepwise, according to the severity and location of the bleeding or the risk of bleeding of the procedure as well as the haemostatic response obtained at each step in order to ensure an optimal benefit/risk ratio. CONCLUSION The lack of data means that it is only possible to issue proposals rather than recommendations.
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Affiliation(s)
| | - Yves Gruel
- Département d'Hématologie-Hémostase, Hôpital Universitaire de Tours, Tours, France
| | - Anne Godier
- Service d'Anesthésie Réanimation, AP-HP, Hôpital Européen Georges Pompidou, Paris, France.,Inserm UMR-S1140, Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Annie Harroche
- CRC MHC, Service d'Hématologie Clinique Hôpital Universitaire Necker Enfants Malades, Laboratoire d'Hématologie Générale, Hôpital Necker, AP-HP, Paris, France
| | - Herve Chambost
- APHM, Hôpital d'Enfants La Timone, Service d'Hématologie Oncologie Pédiatrique et Aix Marseille Univ, INSERM, INRA, C2VN, Marseille, France
| | - Dominique Lasne
- CRC MHC, Service d'Hématologie Clinique Hôpital Universitaire Necker Enfants Malades, Laboratoire d'Hématologie Générale, Hôpital Necker, AP-HP, Paris, France
| | | | - Stephanie Roullet
- Inserm U 1034, Service Anesthésie-Réanimation Pellegrin, Université de Bordeaux, CHU de Bordeaux, Bordeaux, France
| | - Pierre Fontana
- Service d'Angiologie et d'Hémostase, Département de Médecine, Hôpitaux Universitaires de Genève, Genève, Switzerland.,Geneva Platelet Group, Faculté de Médecine, Université de Genève, Genève, Switzerland
| | | | - Emmanuel de Maistre
- Service d'Hématologie Biologique - Secteur Hémostase, Plateau Technique de Biologie, CHU Dijon-Bourgogne, Dijon, France
| | - Valerie Chamouard
- Unité d'Hémostase Clinique, Louis Pradel Hospital, University Claude Bernard, Lyon, France
| | | | - Pierre Albaladejo
- Département d'Anesthésie-Réanimation, CHU Grenoble-Alpes, Grenoble, France.,ThEMAS, TIMC, UMR CNRS 5525, Université Grenoble-Alpes, Grenoble, France
| | - Claude Négrier
- Unité d'Hémostase Clinique, Louis Pradel Hospital, University Claude Bernard, Lyon, France
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50
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Kizilocak H, Yukhtman CL, Marquez-Casas E, Lee J, Donkin J, Young G. Management of perioperative hemostasis in a severe hemophilia A patient with inhibitors on emicizumab using global hemostasis assays. Ther Adv Hematol 2019; 10:2040620719860025. [PMID: 31275538 PMCID: PMC6598318 DOI: 10.1177/2040620719860025] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Accepted: 06/03/2019] [Indexed: 01/17/2023] Open
Abstract
Background: Patients with severe hemophilia A and inhibitors are at risk of bleeding during invasive procedures. The standard of care for preventing perioperative bleeding has been replacement therapy with FVIII concentrates or for patients with high-titer inhibitors, bypassing agents. However, there is no consensus on the appropriate management of surgery in patients receiving the novel agent emicizumab. The aim of this study was to demonstrate a case of a patient on emicizumab undergoing major surgery with bypassing agents with preoperative use of the thrombin generation assay (TGA) and thromboelastography (TEG). Methods: We report a patient with hemophilia A with inhibitors who had undergone a total knee replacement while on emicizumab combined with a bypassing agent. We utilized TEG and TGA to determine which bypassing agent to choose as well as to inform about the ideal dose. Results: We elected to use recombinant FVIIa as a bypassing agent for the surgery based upon the TGA results. Conclusion: The TGA can be utilized to support decision-making in patients on emicizumab undergoing major surgery to both predict efficacy and potentially minimize the risk of thrombotic events.
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Affiliation(s)
- Hande Kizilocak
- Hemostasis and Thrombosis Center, Children's Hospital Los Angeles, 4650 Sunset Boulevard, Mail Stop #54, Los Angeles, CA 90027, USA
| | | | | | - Jeanie Lee
- Children's Hospital Los Angeles, Los Angeles, CA, USA
| | | | - Guy Young
- Children's Hospital Los Angeles, Los Angeles, CA, USA
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