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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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Shapiro AD, Mitchell IS, Nasr S. The future of bypassing agents for hemophilia with inhibitors in the era of novel agents. J Thromb Haemost 2018; 16:2362-2374. [PMID: 30264916 DOI: 10.1111/jth.14296] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Indexed: 01/19/2023]
Abstract
Bypassing agents are presently the standard of care for the treatment of bleeding episodes in patients with hemophilia and high-titer inhibitors and are also used for bleed prevention. Only two bypassing agents are available to patients, and these products trace their lineage to the 1970s (activated prothrombin complex concentrates) and the 1980s (recombinant factor VIIa). Given the limited repertoire of available products, clinicians have relied on experience, empirical observation, registry data and individualized care to improve clinical outcomes on a case-by-case basis. Research over the past two decades has culminated in a greatly improved understanding of human coagulation; resulting from this, new products have been developed that offer treatment options and mechanisms of actions that differ from current bypassing agents. The most advanced in clinical development is emicizumab, a bispecific antibody that mimics the function of FVIIIa in the intrinsic Xase complex and is indicated for once-weekly or every-other-week prophylactic dosing in inhibitor patients. Other non-traditional products in clinical development include fitusiran and antibodies directed against tissue factor pathway inhibitor. As non-factor-based therapies become more widely utilized over time, the use of bypassing agents may be expected to decrease; however, bypassing agents will remain essential for the foreseeable future. As such, clinical development of bypassing agents continues, with some products (e.g. eptacog beta) under regulatory review. In this review we examine the optimal use of bypassing agents and their mechanism of action. We also discuss newer products and how these might theoretically be administered in conjunction with traditional bypassing agents.
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Affiliation(s)
- A D Shapiro
- Indiana Hemophilia and Thrombosis Center, Inc., Indianapolis, IN, USA
| | | | - S Nasr
- GLOVAL, LLC, Broomfield, CO, USA
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Lisman T, de Groot PG. The role of cell surfaces and cellular receptors in the mode of action of recombinant factor VIIa. Blood Rev 2015; 29:223-9. [DOI: 10.1016/j.blre.2014.12.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2014] [Accepted: 12/08/2014] [Indexed: 11/27/2022]
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Mannucci PM. Half-life extension technologies for haemostatic agents. Thromb Haemost 2014; 113:165-76. [PMID: 25274414 DOI: 10.1160/th14-04-0332] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2014] [Accepted: 08/27/2014] [Indexed: 12/18/2022]
Abstract
The use of plasma-derived and recombinant coagulation factors for the treatment of haemophilia A and B is well established and permits patients to live a relatively normal life. In order to improve treatment options, several products are in development, which have a prolonged duration of action, thus enabling less frequent prophylactic dosing and aiming to reduce the burden of treatment. Several innovative approaches are being pursued to extend the half-life of factor VIIa, factor VIII and factor IX, utilising technologies such as Fc fusion, recombinant albumin fusion and addition of polyethyleneglycol (PEG) (PEGylation). These methods prolong the time in the circulation by reducing degradation and elimination. This review summarises the technologies and products in development and their stages of development, and also discusses their pros and cons.
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Affiliation(s)
- Pier Mannuccio Mannucci
- Pier Mannuccio Mannucci, Scientific Director, Angelo Bianchi Bonomi Hemophilia and Thrombosis Center, IRCCS Cà Grande Maggiore Policlinico Hospital Foundation, Milan, Italy, Tel.: +39 02 55038377, Fax: +39 02 50320723, E-mail:
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Promising coagulation factor VIII bypassing strategies for patients with haemophilia A. Blood Coagul Fibrinolysis 2014; 25:539-52. [DOI: 10.1097/mbc.0000000000000098] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Mäde V, Babilon S, Jolly N, Wanka L, Bellmann-Sickert K, Diaz Gimenez LE, Mörl K, Cox HM, Gurevich VV, Beck-Sickinger AG. Peptide Modifications Differentially Alter G Protein-Coupled Receptor Internalization and Signaling Bias. Angew Chem Int Ed Engl 2014. [DOI: 10.1002/ange.201403750] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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Mäde V, Babilon S, Jolly N, Wanka L, Bellmann-Sickert K, Diaz Gimenez LE, Mörl K, Cox HM, Gurevich VV, Beck-Sickinger AG. Peptide modifications differentially alter G protein-coupled receptor internalization and signaling bias. Angew Chem Int Ed Engl 2014; 53:10067-71. [PMID: 25065900 DOI: 10.1002/anie.201403750] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2014] [Indexed: 01/15/2023]
Abstract
Although G protein-coupled receptors (GPCRs) are targeted by more clinically used drugs than any other type of protein, their ligand development is particularly challenging. Humans have four neuropeptide Y receptors: hY1R and hY5R are orexigenic, while hY2R and hY4R are anorexigenic, and represent important anti-obesity drug targets. We show for the first time that PEGylation and lipidation, chemical modifications that prolong the plasma half-lives of peptides, confer additional benefits. Both modifications enhance pancreatic polypeptide preference for hY2R/hY4R over hY1R/hY5R. Lipidation biases the ligand towards arrestin recruitment and internalization, whereas PEGylation confers the opposite bias. These effects were independent of the cell system and modified residue. We thus provide novel insights into the mode of action of peptide modifications and open innovative venues for generating peptide agonists with extended therapeutic potential.
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Affiliation(s)
- Veronika Mäde
- Universität Leipzig, Faculty of Biosciences, Pharmacy and Psychology, Institute of Biochemistry, Brüderstrasse 34, 04103 Leipzig (Germany) http://www.biochemie.uni-leipzig.de/agbs/
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Pfister D, Morbidelli M. Process for protein PEGylation. J Control Release 2014; 180:134-49. [DOI: 10.1016/j.jconrel.2014.02.002] [Citation(s) in RCA: 142] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2014] [Revised: 01/31/2014] [Accepted: 02/03/2014] [Indexed: 11/25/2022]
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Key issues in inhibitor management in patients with haemophilia. BLOOD TRANSFUSION = TRASFUSIONE DEL SANGUE 2013; 12 Suppl 1:s319-29. [PMID: 24333092 DOI: 10.2450/2013.0246-12] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Subscribe] [Scholar Register] [Received: 10/29/2012] [Accepted: 05/16/2013] [Indexed: 12/13/2022]
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Ljung R, Karim FA, Saxena K, Suzuki T, Arkhammar P, Rosholm A, Giangrande P. 40K glycoPEGylated, recombinant FVIIa: 3-month, double-blind, randomized trial of safety, pharmacokinetics and preliminary efficacy in hemophilia patients with inhibitors. J Thromb Haemost 2013; 11:1260-8. [PMID: 23578227 DOI: 10.1111/jth.12237] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2012] [Accepted: 04/03/2013] [Indexed: 11/29/2022]
Abstract
BACKGROUND A 40K glycoPEGylated, recombinant activated factor VII (rFVIIa) bypassing agent (N7-GP) with a prolonged half-life (15 h) compared with rFVIIa was developed as a potential candidate for bleed-preventive regimens in patients with hemophilia and inhibitors. OBJECTIVES To evaluate the safety, pharmacokinetics and preliminary efficacy of multiple doses of N7-GP in congenital hemophilia A and B patients with high-titer inhibitors. PATIENTS/METHODS In this global, prospective, randomized, double-blinded, phase 2 trial, 25, 100 or 200 μg kg(-1) N7-GP was administered intravenously once every second day during a 3-month, bleed-preventive regimen and compared with a preceding 3-month observation period with on-demand treatment of bleeds with rFVIIa. The primary endpoint was adverse events; secondary endpoints were evaluation of immunogenicity, pharmacokinetics and efficacy. RESULTS AND CONCLUSIONS Overall, 23 patients were randomized and dosed (n = 8/7/8 for 25/100/200 μg kg(-1) ). N7-GP was well tolerated, with a low frequency of adverse events. No serious adverse events, immunogenic or thromboembolic events related to N7-GP were reported. The pharmacokinetic properties of N7-GP were similar to those reported in phase 1. The annualized bleeding rate (ABR) decreased in the treatment period vs. the observation period at all N7-GP dose levels. However, a dose-response relationship in the reduction could not be established in the N7-GP dose range evaluated. The ABR was also reduced at two dose levels during the last part of the observation period, and increased notably in the follow-up period irrespective of previous N7-GP dose. The trial was registered at ClinicalTrials.gov ( REGISTRATION NUMBER NCT00951405).
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Affiliation(s)
- R Ljung
- Department of Paediatrics and Malmö Centre for Thrombosis and Haemostasis, Lund University, Skåne University Hospital, Malmö, Sweden.
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Factor VIIa. Platelets 2013. [DOI: 10.1016/b978-0-12-387837-3.00061-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Clark CA, Vatsyayan R, Hedner U, Esmon CT, Pendurthi UR, Rao LVM. Endothelial cell protein C receptor-mediated redistribution and tissue-level accumulation of factor VIIa. J Thromb Haemost 2012; 10:2383-91. [PMID: 22950420 PMCID: PMC3528836 DOI: 10.1111/j.1538-7836.2012.04917.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2012] [Accepted: 08/30/2012] [Indexed: 11/27/2022]
Abstract
BACKGROUND Recent studies show that activated factor VII (FVIIa) binds to the endothelial cell protein C receptor (EPCR) on the vascular endothelium; however, the importance of this interaction in hemostasis or pathophysiology is unknown. OBJECTIVE The aim of the present study was to investigate the role of the FVIIa interaction with EPCR on the endothelium in mediating FVIIa transport from the circulation to extravascular tissues. METHODS Wild-type, EPCR-deficient or ECPR-over-expressing mice were injected with human recombinant (r)FVIIa (120 μg kg(-1) body weight) via the tail vein. At varying time intervals after rFVIIa administration, blood and various tissues were collected to measure FVIIa antigen and activity levels. Tissue sections were analyzed by immunohistochemistry for FVIIa and EPCR. RESULTS The data reveal that, after intravenous (i.v.) injection, rFVIIa rapidly disappears from the blood and associates with the endothelium in an EPCR-dependent manner. Immunohistochemical analyses revealed that the association of FVIIa with the endothelium was maximal at 30 min and thereafter progressively declined. The FVIIa association with the endothelium was undetectable at time points exceeding 24 h post-FVIIa administration. The levels of rFVIIa accumulated in tissue correlate with expression levels of EPCR in mice and FVIIa associated with tissues remained functionally active for periods of at least 7 days. CONCLUSIONS The observation that an EPCR-dependent association of FVIIa with the endothelium is most pronounced soon after rFVIIa administration and subsequently declines temporally, combined with the retention of functionally active FVIIa in tissue homogenates for extended periods, indicates that FVIIa binding to EPCR on the endothelium facilitates the transport of FVIIa from circulation to extravascular tissues where TF resides.
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Affiliation(s)
- C A Clark
- Department of Cellular and Molecular Biology, Center for Biomedical Research, The University of Texas Health Science Center at Tyler, Tyler, TX, USA Department of Medicine, Malmö University Hospital, University of Lund, Malmö, Sweden Cardiovascular Biology Research Program, Oklahoma Medical Research Foundation, Howard Hughes Medical Institute, Oklahoma City, OK, USA
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Franchini M, Mannucci PM. Past, present and future of hemophilia: a narrative review. Orphanet J Rare Dis 2012; 7:24. [PMID: 22551339 PMCID: PMC3502605 DOI: 10.1186/1750-1172-7-24] [Citation(s) in RCA: 146] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2011] [Accepted: 03/29/2012] [Indexed: 12/19/2022] Open
Abstract
Over the past forty years the availability of coagulation factor replacement therapy has greatly contributed to the improved care of people with hemophilia. Following the blood-borne viral infections in the late 1970s and early 1980, caused by coagulation factor concentrates manufactured using non-virally inactivated pooled plasma, the need for safer treatment became crucial to the hemophilia community. The introduction of virus inactivated plasma-derived coagulation factors and then of recombinant products has revolutionized the care of these people. These therapeutic weapons have improved their quality of life and that of their families and permitted home treatment, i.e., factor replacement therapy at regular intervals in order to prevent both bleeding and the resultant joint damage (i.e. primary prophylaxis). Accordingly, a near normal lifestyle and life-expectancy have been achieved. The main current problem in hemophilia is the onset of alloantibodies inactivating the infused coagulation factor, even though immune tolerance regimens based on long-term daily injections of large dosages of coagulation factors are able to eradicate inhibitors in approximately two-thirds of affected patients. In addition availability of products that bypass the intrinsic coagulation defects have dramatically improved the management of this complication. The major challenges of current treatment regimens, such the short half life of hemophilia therapeutics with need for frequent intravenous injections, encourage the current efforts to produce coagulation factors with more prolonged bioavailability. Finally, intensive research is devoted to gene transfer therapy, the only way to ultimately obtain cure in hemophilia.
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Affiliation(s)
- Massimo Franchini
- Immunohematology and Transfusion Center, Department of Pathology and Laboratory Medicine, University Hospital of Parma, Milan, Italy
| | - Pier Mannuccio Mannucci
- Scientific Direction, IRCCS Cà Granda Foundation Maggiore Policlinico Hospital, Via Pace, 9, 20122, Milan, Italy
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Abstract
Tissue factor (TF)-initiated coagulation plays a critical role in both hemostasis and thrombosis. It is generally believed that most of the tissue factor expressed on cell surfaces is maintained in a cryptic, i.e., coagulantly inactive state and an activation step (decryption) is required for the expression of maximum TF procoagulant activity. However, what exactly constitutes cryptic or procoagulant TF, molecular differences between these two forms and mechanisms that are responsible for transformation from one to the other form are not entirely clear and remain highly controversial, thus are a matter of ongoing debate. This brief review discusses pertinent literature on TF encryption/decryption with specific emphasis on the role of membrane phospholipids and reduction/oxidation of the TF Cys186-Cys209 disulfide bond in regulating TF activity at cell surfaces.
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Affiliation(s)
- L Vijaya Mohan Rao
- Center for Biomedical Research, The University of Texas Health Science Center at Tyler, Tyler, TX, USA.
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Abstract
It is generally believed that only a small fraction of the tissue factor (TF) found on cell surfaces is active whereas the vast majority is cryptic in coagulation. It is unclear how cryptic TF differs from the coagulant active TF or potential mechanisms involved in transformation of cryptic TF to the coagulant active form. Exposure of phosphatidylserine (PS) in response to various chemical or pathophysiological stimuli has been considered as the most potent inducer of TF decryption. In addition to PS, TF self-association and association with specialized membrane domains may also play a role in TF decryption. It has been suggested recently that protein disulfide isomerase regulates TF decryption through its oxidoreductase activity by targeting Cys186-Cys209 disulfide bond in TF extracellular domain or regulating the PS equilibrium at the plasma membrane. However, this hypothesis requires further validation to become an accepted mechanism. In this article, we critically review literature on TF encryption/decryption with specific emphasis on recently published data and provide our perspective on this subject.
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Affiliation(s)
- L Vijaya Mohan Rao
- Center for Biomedical Research, The University of Texas Health Science Center at Tyler, Tyler, Texas 75708, USA.
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Abstract
The complex of the serine protease factor IX (FIX) and its cofactor, factor VIII (FVIII), is crucial for propagation of the intrinsic coagulation cascade. Absence of either factor leads to hemophilia, a disabling disorder marked by excessive hemorrhage after minor trauma. FVIII is the more commonly affected protein, either by X-chromosomal gene mutations or in autoimmune-mediated acquired hemophilia. Whereas substitution of FVIII is the mainstay of hemophilia A therapy, treatment of patients with inhibitory Abs remains challenging. In the present study, we report the development of FIX variants that can propagate the intrinsic coagulation cascade in the absence of FVIII. FIX variants were expressed in FVIII-knockout (FVIII-KO) mice using a nonviral gene-transfer system. Expression of the variants shortened clotting times, reduced blood loss after tail-clip assay, and reinstalled clot formation, as tested by in vivo imaging of laser-induced vessel injury. In addition, we confirmed the therapeutic efficacy of FIX variants in mice with inhibitory Abs against FVIII. Further, mice tolerant to wild-type human FIX did not develop immune responses against the protein variants. Our results therefore indicate the feasibility of using variants of FIX to bypass FVIII as a novel treatment approach in hemophilia with and without neutralizing FVIII Abs.
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Plesner B, Westh P, Nielsen AD. The effect of GlycoPEGylation on the physical stability of human rFVIIa with increasing calcium chloride concentration. Eur J Pharm Biopharm 2011; 78:222-8. [DOI: 10.1016/j.ejpb.2010.12.037] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2010] [Revised: 12/15/2010] [Accepted: 12/16/2010] [Indexed: 10/18/2022]
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Abstract
Proteases are an expanding class of drugs that hold great promise. The U.S. FDA (Food and Drug Administration) has approved 12 protease therapies, and a number of next generation or completely new proteases are in clinical development. Although they are a well-recognized class of targets for inhibitors, proteases themselves have not typically been considered as a drug class despite their application in the clinic over the last several decades; initially as plasma fractions and later as purified products. Although the predominant use of proteases has been in treating cardiovascular disease, they are also emerging as useful agents in the treatment of sepsis, digestive disorders, inflammation, cystic fibrosis, retinal disorders, psoriasis and other diseases. In the present review, we outline the history of proteases as therapeutics, provide an overview of their current clinical application, and describe several approaches to improve and expand their clinical application. Undoubtedly, our ability to harness proteolysis for disease treatment will increase with our understanding of protease biology and the molecular mechanisms responsible. New technologies for rationally engineering proteases, as well as improved delivery options, will expand greatly the potential applications of these enzymes. The recognition that proteases are, in fact, an established class of safe and efficacious drugs will stimulate investigation of additional therapeutic applications for these enzymes. Proteases therefore have a bright future as a distinct therapeutic class with diverse clinical applications.
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The molar hydrodynamic volume changes of factor VIIa due to GlycoPEGylation. J Pharm Biomed Anal 2011; 55:597-602. [PMID: 21429688 DOI: 10.1016/j.jpba.2011.02.028] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2010] [Revised: 02/22/2011] [Accepted: 02/23/2011] [Indexed: 11/23/2022]
Abstract
The effects of GlycoPEGylation on the molar hydrodynamic volume of recombinant human rFVIIa were investigated using rFVIIa and two GlycoPEGylated recombinant human FVIIa derivatives, a linear 10kDa PEG and a branched 40kDa PEG, respectively. Molar hydrodynamic volumes were determined by capillary viscometry and mass spectrometry. The intrinsic viscosities of rFVIIa, its two GlycoPEGylated compounds, and of linear 8kDa, 10kDa, 20kDa and branched 40kDa PEG polymers were determined. The measured intrinsic viscosity of rFVIIa is 6.0mL/g, while the intrinsic viscosities of 10kDa PEG-rFVIIa and 40kDa PEG-rFVIIa are 29.5mL/g and 79.0mL/g, respectively. The intrinsic viscosities of the linear PEG polymers are 20, 22.6 and 41.4mL/g for 8, 10, and 20kDa, respectively, and 61.1mL/g for the branched 40kDa PEG. From the results of the intrinsic viscosity and MALDI-TOF measurements it is evident, that the molar hydrodynamic volume of the conjugated protein is not just an addition of the molar hydrodynamic volume of the PEG and the protein. The molar hydrodynamic volume of the GlycoPEGylated protein is larger than the volume of its composites. These results suggest that both the linear and the branched PEG are not wrapped around the surface of rFVIIa but are chains that are significantly stretched out when attached to the protein.
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