3351
|
|
3352
|
Surmali Onay O, Baskin E, Ozçay F, Melek E, Canan O, Bilezikçi B. Successful treatment of hepatitis B-associated leukocytoclastic vasculitis with lamivudine treatment in a child patient. Rheumatol Int 2007; 27:869-72. [PMID: 17252264 DOI: 10.1007/s00296-006-0295-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2006] [Accepted: 12/02/2006] [Indexed: 11/30/2022]
Abstract
Chronic hepatitis B infection (HBI) has many extrahepatic manifestations such as vasculitis, glomerulonephritis, arthritis, dermatitis, pulmonary disease, and skin manifestations. The mechanism of these manifestations is thought to be immune mediated. Immune-suppressive treatment may enhance viral replication and worsen hepatic disease. Lamivudine is a nucleoside analogue used in chronic HBI treatment that works by suppressing replication of the hepatitis B virus (HBV). Recently, several reports have suggested that lamivudine treats vasculitis associated with HBV infection in adults. However, there are no data in the literature for children. Herein, we report a child with leukocytoclastic vasculitis due to chronic HBI who was successfully treated with lamivudine.
Collapse
Affiliation(s)
- Ozge Surmali Onay
- Department of Pediatric Nephrology, Başkent University Faculty of Medicine, 6. Cadde, No:72/3, 06490 Bahçelievler, Ankara, Turkey
| | | | | | | | | | | |
Collapse
|
3353
|
Abstract
Recombinant activated coagulation factor VII (rFVIIa) was developed initially for treatment of patients with hemophilia and neutralizing antibodies ("inhibitors") to coagulation factors VIII or IX. Owing to the unique and selective mechanism of action of rFVIIa and encouraged by clinical experience with other circumstances of inadequate hemostasis, a broad development program has been pursued to test potential efficacy and evaluate safety of this biologic for indications other than hemophilia. This review summarizes the current development of rFVIIa, focusing on results of prospective, randomized clinical trials.
Collapse
Affiliation(s)
- R B Weiskopf
- Novo Nordisk A/S, Novo Allé, DK-2880 Bagsvaerd, Denmark.
| |
Collapse
|
3354
|
Mathew P, Simon TL, Hunt KE, Crookston KP. How we manage requests for recombinant factor VIIa (NovoSeven). Transfusion 2007; 47:8-14. [PMID: 17207224 DOI: 10.1111/j.1537-2995.2007.01058.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Prasad Mathew
- Department of Pathology, University of New Mexico, New Mexico, USA
| | | | | | | |
Collapse
|
3355
|
Senzolo M, Burra P, Cholongitas E, Burroughs AK. New insights into the coagulopathy of liver disease and liver transplantation. World J Gastroenterol 2006; 12:7725-36. [PMID: 17203512 PMCID: PMC4087534 DOI: 10.3748/wjg.v12.i48.7725] [Citation(s) in RCA: 113] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The liver is an essential player in the pathway of coagulation in both primary and secondary haemostasis. Only von Willebrand factor is not synthetised by the liver, thus liver failure is associated with impairment of coagulation. However, recently it has been shown that the delicate balance between pro and antithrombotic factors synthetised by the liver might be reset to a lower level in patients with chronic liver disease. Therefore, these patients might not be really anticoagulated in stable condition and bleeding may be caused only when additional factors, such as infections, supervene. Portal hypertension plays an important role in coagulopathy in liver disease, reducing the number of circulating platelets, but platelet function and secretion of thrombopoietin have been also shown to be impaired in patients with liver disease. Vitamin K deficiency may coexist, so that abnormal clotting factors are produced due to lack of gamma carboxylation. Moreover during liver failure, there is a reduced capacity to clear activated haemostatic proteins and protein inhibitor complexes from the circulation. Usually therapy for coagulation disorders in liver disease is needed only during bleeding or before invasive procedures. When end stage liver disease occurs, liver transplantation is the only treatment available, which can restore normal haemostasis, and correct genetic clotting defects, such as haemophilia or factor V Leiden mutation. During liver transplantation haemorrage may occur due to the pre-existing hypocoagulable state, the collateral circulation caused by portal hypertension and increased fibrinolysis which occurs during this surgery.
Collapse
Affiliation(s)
- M Senzolo
- Department of Surgical and Gastroenterological Sciences, University Hospital of Padua, Padua, Italy.
| | | | | | | |
Collapse
|
3356
|
STEINER MARIEE, KEY NIGELS. Use of recombinant activated factor VII in the management of medical and surgical bleeding: a critical review. ACTA ACUST UNITED AC 2006. [DOI: 10.1111/j.1778-428x.2006.00033.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
|
3357
|
Hardy JF, de Moerloose P, Samama CM. Massive transfusion and coagulopathy: pathophysiology and implications for clinical management. Can J Anaesth 2006; 53:S40-58. [PMID: 16766790 PMCID: PMC7103890 DOI: 10.1007/bf03022251] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
PURPOSE To review the pathophysiology of coagulopathy in massively transfused, adult and previously hemostatically competent patients in both elective surgical and trauma settings, and to recommend the most appropriate treatment strategies. METHODS Medline was searched for articles on "massive transfusion," "transfusion," "trauma," "surgery," "coagulopathy" and "hemostatic defects." A group of experts reviewed the findings. PRINCIPAL FINDINGS Coagulopathy will result from hemodilution, hypothermia, the use of fractionated blood products and disseminated intravascular coagulation. The clinical significance of the effects of hydroxyethyl starch solutions on hemostasis remains unclear. Maintaining a normal body temperature is a first-line, effective strategy to improve hemostasis during massive transfusion. Red cells play an important role in coagulation and hematocrits higher than 30% may be required to sustain hemostasis. In elective surgery patients, a decrease in fibrinogen concentration is observed initially while thrombocytopenia is a late occurrence. In trauma patients, tissue trauma, shock, tissue anoxia and hypothermia contribute to the development of disseminated intravascular coagulation and microvascular bleeding. The use of platelets and/or fresh frozen plasma should depend on clinical judgment as well as the results of coagulation testing and should be used mainly to treat a clinical coagulopathy. CONCLUSIONS Coagulopathy associated with massive transfusion remains an important clinical problem. It is an intricate, multifactorial and multicellular event. Treatment strategies include the maintenance of adequate tissue perfusion, the correction of hypothermia and anemia, and the use of hemostatic blood products to correct microvascular bleeding.
Collapse
Affiliation(s)
- Jean-François Hardy
- Department of Anesthesology, Centre Hospitalier de l'Université de Montréal, Canada.
| | | | | |
Collapse
|
3358
|
Shaya FT, Gbarayor CM, Agyeman-Duah M, Saunders E. A perspective on African American participation in clinical trials. Contemp Clin Trials 2006; 28:213-7. [PMID: 17141575 DOI: 10.1016/j.cct.2006.10.001] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2005] [Revised: 06/28/2006] [Accepted: 10/03/2006] [Indexed: 01/13/2023]
Abstract
The relatively low participation of African Americans in phase III clinical trials has raised concerns about the appropriateness of generalizing study results to African American populations. If African American enrollment in clinical trials continues to be low, the society may continue to see disparities in the treatment of diseases as well as unanswered questions as to why the population fares less than others when diagnosed with certain diseases such as cancer and diabetes. Additionally, more clinical trials are needed to explicitly monitor the difference in outcomes across different populations. This article discusses the various reasons why African American patient recruitment and participation is sub-optimal; the critical role of clinical trials in therapies; recommendations by important authorities; and a new practice model (Collaborative Care Model) as an innovative strategy to augment participation rates of African Americans [and other minorities] in clinical trials.
Collapse
Affiliation(s)
- Fadia T Shaya
- Center on Drugs and Public Policy, University of Maryland School of Pharmacy, Pharmaceutical Health Services Research, 220 Arch Street, Baltimore, MD 21201, USA.
| | | | | | | |
Collapse
|
3359
|
|
3360
|
Akyildiz M, Turan I, Ozutemiz O, Batur Y, Ilter T. A cerebrovascular event after single-dose administration of recombinant factor VIIa in a patient with esophageal variceal bleeding. Dig Dis Sci 2006; 51:1647-9. [PMID: 16927152 DOI: 10.1007/s10620-005-9023-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/27/2005] [Accepted: 08/24/2005] [Indexed: 12/15/2022]
Abstract
Upper gastrointestinal bleeding (UGIB) is a life-threatening complication of cirrhosis that develops from esophageal varices in almost 70% of patients. The mortality rate from the bleeding episodes is reported to be 30% [1-4]. Standard management of UGIB of cirrhotic patients is vasoactive therapy combined with endoscopic procedures such as endoscopic sclerotherapy and band ligation [5]. Currently, it is reported that recombinant activated fVIIa (Novoseven, NovoNordisc) can correct the prothrombin time in decompensated cirrhotic patients and also can be used safely in Child's B and C cirrhotic patients with UGIB [6-8]. Herein, we describe the first case report in the literature of a cerebrovascular event after the administration of a single dose of fVIIa in a cirrhotic patient with esophageal variceal bleeding.
Collapse
Affiliation(s)
- Murat Akyildiz
- The Department of Gastroenterology, Ege University Medical School, Bornova, 35040 Izmir, Turkey.
| | | | | | | | | |
Collapse
|
3361
|
Abstract
The author reviewed the literature regarding recombinant activated Factor VII (rFVIIa) in major abdominal surgery and liver transplantation and concluded that, on the basis of evidence-based medicine, there is no evidence to support an extensive use of rFVIIa. Nevertheless, various case reports suggest the usefulness of rFVIIa to treat life-threatening bleeding after failure of conventional therapies. It appears that there is a consensus that rFVIIa can be used with good results as a rescue therapy in extremely severe situations. Economic cost and potential thrombosis risk remain arguments against more widespread use of rFVIIa. Doses from 5 to 120 kg/kg in each administration have been reported without clear evidence to support a specific protocol. Efficacy of 15 to 20 kg/kg in surgical settings has been reported, but higher doses are more frequently used. The majority of the reviewed investigators accepted the use of rFVIIa after or simultaneously with the use of aprotinin; no data refute the safety of this association.
Collapse
|
3362
|
Abstract
PURPOSE OF REVIEW Bleeding remains a challenge in surgery. A unique drug, recombinant factor VIIa, causes clotting exclusively at bleeding sites. Recombinant factor VIIa has recently been introduced to surgery where current evidence, consisting mostly of case reports, suggest remarkable safety and efficacy. The first randomized controlled trials are only now being published with less remarkable results. This manuscript summarizes the current evidence. RECENT FINDINGS In trauma, a single randomized control trial suggests recombinant factor VIIa reduces bleeding and transfusion in blunt trauma, particularly in coagulopathic patients. In cardiac surgery, one randomized control trial, open-label studies and case reports suggest benefit in refractory bleeding. For liver surgery, randomized control trials do not support use in liver transplant or gastrointestinal bleeding. In neurosurgery, one randomized control trial demonstrated improved outcome in intracerebral hemorrhage. In urology, one randomized control trial demonstrated significant reduction in perioperative bleeding. For orthopedics, a single randomized control trial showed no benefit in pelvic/acetabular surgery. In obstetrics/gynecology, limited evidence suggests benefit in massive bleedings. SUMMARY Current evidence does not yet support recombinant factor VIIa as standard of care in surgery. However, the evidence indicates that recombinant factor VIIa should be used in intracerebral hemorrhage and massive perioperative or traumatic bleeding refractory to conventional therapies. For now, the bedside decision to use recombinant factor VIIa remains a matter of surgical judgment.
Collapse
Affiliation(s)
- Sandro Scarpelini
- Trauma and Emergency Surgery, Faculty of Medicine of Ribeirão Preto, University of São Paulo, Brazil
| | | |
Collapse
|
3363
|
Das P, Carcao M, Hitzler J. Use of recombinant factor VIIa prior to lumbar puncture in pediatric patients with acute leukemia. Pediatr Blood Cancer 2006; 47:206-9. [PMID: 16007583 DOI: 10.1002/pbc.20467] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The persistence of abnormal coagulation test results after standard treatment with fresh frozen plasma (FFP) poses significant problems in children with acute leukemia requiring a diagnostic lumbar puncture and intrathecal chemotherapy. We report the prophylactic use of a single dose of 90 microg/kg recombinant activated factor VII (rFVIIa) in three children and the rapid correction of abnormal coagulation test results previously not corrected by FFP. Administration of rFVIIa was useful in avoiding a delay of diagnostic lumbar punctures and intrathecal chemotherapy. Hemorrhagic complications and adverse effects of rFVIIa were not observed. Prospective evaluation of this indication and dose appears warranted. (c) 2005 Wiley-Liss, Inc.
Collapse
Affiliation(s)
- Prabodh Das
- The Hospital for Sick Children, Division of Hematology/Oncology, Department of Pediatrics, University of Toronto, Toronto, Ontario M5G1X8, Canada
| | | | | |
Collapse
|
3364
|
Abstract
The liver plays a central role in the maintenance of normal hemostatic function. Because liver disease alters pathways of coagulation and anticoagulation, patients who have advanced disease can experience severe bleeding or thrombotic complications. Complications of advanced liver disease may also contribute to bleeding or thrombosis. This article reviews and discusses the management of the most common coagulation problems encountered in patients who have end-stage liver disease, which are thrombocytopenia and impaired humoral coagulation as measured by prolongation of the prothrombin time and international normalized ratio.
Collapse
Affiliation(s)
- James F Trotter
- Division of Gastroenterology/Hepatology, University of Colorado Health Sciences Center, 4200 East 9th Avenue, B-154 Denver, CO 80262, USA.
| |
Collapse
|
3365
|
McMullin NR, Kauvar DS, Currier HM, Baskin TW, Pusateri AE, Holcomb JB. The Clinical and Laboratory Response to Recombinant Factor VIIa in Trauma and Surgical Patients with Acquired Coagulopathy. ACTA ACUST UNITED AC 2006; 63:246-51. [PMID: 16843774 DOI: 10.1016/j.cursur.2006.03.007] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
OBJECTIVE In bleeding patients who are coagulopathic, the clinical response to administration of recombinant factor VIIa (rFVIIa) relates to the changes in prothrombin time (PT). DESIGN Retrospective review of all surgical and trauma patients who were coagulopathic and received factor VIIa at the authors' institution over the past 27 months. SETTING Academic tertiary referral facility and level I trauma center. PARTICIPANTS Eighteen patients met inclusion criteria, 10 trauma and 8 surgical. Mean age 50 years (range, 17-84). RESULTS Overall mortality was 39%. All but 1 patient (17/18) had resolution of coagulopathic bleeding with rFVIIa, and all clinical responders (n = 17) (defined as clinical cessation of bleeding within 24 hours determined by either attending surgeon or chief resident progress note) had a decrease in PT to normal range. In contrast, the single clinical nonresponder had an insignificant PT decrease (19 to 18 seconds). Prothrombin time decreased from 20 +/- 4 seconds to 12 +/- 2 seconds, p < 0.05 (n = 17). International Normalized Ratio (INR) decreased from 1.59 to 0.86, p < 0.05 (n = 17). Fibrinogen before administration was 299.73 (range, 105-564) (n = 15). pH before administration was 7.25 (+/-0.18) (n = 10). Patient temperature was 98.64 (+/-2.06). Effect in partial thromboplastin time (PTT) was inconsistent (50 +/- 49 seconds to 34 +/- 6 seconds, p > 0.05). Transfusion requirements for red blood cells (14 to 3 units) and plasma (12 to 3 units) were significantly reduced after rFVIIa. There were no significant differences in percentage PT decrease between dose > or =100 mcg/kg vs <100 mcg/kg, surgical vs trauma patients, survivors vs nonsurvivors, and those with pretreatment platelet count > or =100 K vs <100 K. CONCLUSIONS The administration of rFVIIa caused a decrease in the PT in nearly all patients. There were an insufficient number of patients to support the use of PT as a clinical predictor of response; however, the data are suggestive of such utility. If the PT does not correct, then it is likely that there is a deficiency of other factors of the coagulation cascade.
Collapse
Affiliation(s)
- Neil R McMullin
- United States Army Institute of Surgical Research, Fort Sam Houston, TX 78234, USA
| | | | | | | | | | | |
Collapse
|
3366
|
Park JH, Kim KL, Cho EW. Detection of surface asialoglycoprotein receptor expression in hepatic and extra-hepatic cells using a novel monoclonal antibody. Biotechnol Lett 2006; 28:1061-9. [PMID: 16799763 DOI: 10.1007/s10529-006-9064-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2006] [Accepted: 03/28/2006] [Indexed: 11/26/2022]
Abstract
The asialoglycoprotein receptor (ASGPR) is a heterodimeric membrane protein which is involved in the internalization of desialylated glycoproteins and also in the binding and uptake of various pathogenic viruses. To facilitate the analysis of ASGPR expression, we generated a monoclonal antibody, termed ASSA-1, that is specific to the ASGPR H1 subunit based on ELISA and Western blots analysis. ASSA-1 also reacted to surface-displayed ASGPR in live cells thus enabling analysis of ASGPR expression by immunofluorescence flow cytometry, which we used to analyze established human liver cell lines previously confirmed to be positive for ASGPR mRNA expression. In agreement with previous reports, surface ASGPR was also detected in extra-hepatic cells and, surprisingly, even in human T cell lines, which was then further confirmed in activated, but not in resting, primary human peripheral blood lymphocytes. These observations suggest that ASGPR has a broad pattern of expression that even extends into cells from the immune system, which biological meanings still have to be analyzed. We expect that monoclonal antibody ASSA-1 will serve as a new powerful tool in analyzing the biological role of ASGPR in hepatic and extra-hepatic cells.
Collapse
Affiliation(s)
- Jung-Hyun Park
- Systemic Proteomics Research Center, Korea Research Institute of Bioscience and Biotechnology, Yusong, Daejon, South Korea
| | | | | |
Collapse
|
3367
|
Niemann CU, Behrends M, Quan D, Eilers H, Gropper MA, Roberts JP, Hirose R. Recombinant factor VIIa reduces transfusion requirements in liver transplant patients with high MELD scores. Transfus Med 2006; 16:93-100. [PMID: 16623915 DOI: 10.1111/j.1365-3148.2006.00653.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Patients undergoing orthotopic liver transplantation (OLT) often experience significant coagulopathy and remain at risk for excessive blood loss and massive transfusion. The ability of recombinant factor VIIa (rFVIIa) to reduce transfusion requirements during OLT has not been well established. This retrospective study investigates whether rFVIIa reduces transfusion requirements in liver transplant patients with a significantly prolonged prothrombin time (PT) and a model of end-stage liver disease (MELD) score of > 20. Eleven patients received a single dose of rFVIIa (58 +/- 18 microg kg(-1)) at the time of incision. This group was matched with a selected control group that fulfilled all of the inclusion/exclusion criteria. Patient characteristics, pre-operative PT, HCT, PLT and MELD were identical between groups. Prophylactic application of rFVIIA reduced packed red blood cells (3.9 +/- 2.6 versus 6.9 +/- 2.3 U, P = 0.01) and fresh-frozen plasma (FFP) (12.6 +/- 6 versus 19.8 +/- 7 U, P = 0.018) transfusion requirements when compared with the control group. FFP administration in the first 24 h after surgery was also significantly less in the rVIIa group when compared with the control group (388 +/- 385 versus 1225 +/- 701 mL, P = 0.003). Hospital stay following transplantation tended to be shorter in the rFVIIa group, albeit statistical significance was not achieved (11 +/- 7.3 versus 7.9 +/- 2.7, P = 0.2). All but one patient in the control group survived for 30 days after transplantation. In a selected group of patients with prolonged PT and high MELD score, the prophylactic application of rFVIIa at the start of the OLT may reduce perioperative transfusion requirements.
Collapse
Affiliation(s)
- C U Niemann
- Department of Anesthesia and Perioperative Care, University of California, San Francisco, CA 94143-0648, USA.
| | | | | | | | | | | | | |
Collapse
|
3368
|
Inagaki M, Mori T, Tsunematsu Y, Ambo H, Kawai Y. Use of recombinant activated factor VII to control bleeding in a young child with qualitative platelet disorder: a case report. Blood Coagul Fibrinolysis 2006; 17:317-22. [PMID: 16651876 DOI: 10.1097/01.mbc.0000224853.50248.6f] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Defects of platelet adhesion, aggregation, secretion, or procoagulant activities can lead to bleeding diathesis of variable severity. We used recombinant activated factor VII (rFVIIa) in the treatment of uncontrolled epistaxis in a patient with a qualitative platelet disorder. We aimed to assess the efficacy of a single rFVIIa dose (100 microg/kg) in the control of mild and severe refractory epistaxis, and evaluate the influence of rFVIIa on markers of platelet adhesion and aggregation during a period of hematological stability (i.e. non-bleeding, no medication). The efficacy study showed mild episodes of epistaxis could be successfully managed using a single rFVIIa (100 microg/kg) dose; however, severe bleedings were not well controlled, and platelet transfusion was required to achieve hemostasis. Hematological investigations showed ADP-induced and collagen-induced platelet aggregation increases from 20 to 34% and 16 to 30%, respectively, following rFVIIa administration. There were no differences between pre-dose and post-dose concentrations of membrane glycoproteins. rFVIIa may therefore induce platelet aggregation by activating a glycoprotein-independent aggregation pathway. rFVIIa may have a role in managing mild bleeding episodes not controlled using conventional measures in patients with a qualitative platelet disorder. Further research is needed to determine the mechanism of action, efficacy, and safety of rFVIIa in this population.
Collapse
|
3369
|
Levy JH, Fingerhut A, Brott T, Langbakke IH, Erhardtsen E, Porte RJ. Recombinant factor VIIa in patients with coagulopathy secondary to anticoagulant therapy, cirrhosis, or severe traumatic injury: review of safety profile. Transfusion 2006; 46:919-33. [PMID: 16734808 DOI: 10.1111/j.1537-2995.2006.00824.x] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
BACKGROUND In recent years, the hemostatic agent recombinant factor VIIa (rFVIIa) has emerged as a potentially new therapeutic agent for management of coagulopathy in patients with cirrhosis or following severe traumatic injury, a complex problem for clinicians in which standard treatment strategies are not always effective. As with other hemostatic agents, a primary safety concern of rFVIIa therapy is the theoretical possibility that systemic administration could confer an increased risk of thrombotic complications. So far, clinical experience indicates rFVIIa to be a safe treatment for currently approved indications within hemophilia. Little information is available, however, for patient populations outside this clinical setting. STUDY DESIGN AND METHODS This article reviews critical safety data obtained from 13 Novo Nordisk-sponsored clinical trials of rFVIIa in patients with coagulopathy secondary to anticoagulant therapy, cirrhosis, or severe traumatic injury. RESULTS Thrombotic adverse events were reported for 5.3 percent (23/430) of placebo-treated patients and 6.0 percent (45/748) of patients on active treatment. No significant difference was found between placebo-treated and rFVIIa-treated patients with respect to the incidence of thrombotic AEs, either on an individual trial basis or for these trial populations combined (p=0.57). CONCLUSION An important determinant for the safety profile reported here is likely to be the specific mechanism of action of rFVIIa, shown in experimental studies to be localized to the site of vascular injury where tissue factor is exposed.
Collapse
Affiliation(s)
- Jerrold H Levy
- Department of Anesthesiology, Emory University Hospital, Atlanta, Georgia, USA
| | | | | | | | | | | |
Collapse
|
3370
|
Weitzman G, Jacobson I. Peginterferon α-2b in the treatment of hepatitis C. Future Virol 2006. [DOI: 10.2217/17460794.1.3.279] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Hepatitis C virus (HCV) is a leading public health problem affecting as many as 4 million Americans. Chronic HCV infection can progress to hepatocellular carcinoma, cirrhosis and death. Interferon-α-based therapies, initially as monotherapy and later in combination with ribavirin, have proven effective in the treatment of HCV infection, but standard interferon is hampered pharmacokinetically by a short half life. With the advent of the pegylated-interferons, administered in combination with oral ribavirin, the chances for HCV eradication have improved further. Peginterferon α-2b, the formuation discussed in this review, provides greater antiviral pressure while maintaining a tolerable side-effect profile with more convenient once-weekly dosing. Clinical trials have focused on treatment-naïve patients as well as on many different HCV subpopulations, including difficult-to-treat patients such as previous interferon therapy failures and patients with HCV cirrhosis.
Collapse
Affiliation(s)
- Gil Weitzman
- Weill Medical College of Cornell University, 1300 York Avenue, F-231, New York, NY 10021, USA
| | - Ira Jacobson
- Weill Medical College of Cornell University, 450 E. 69th Street, New York, NY 10021, USA
| |
Collapse
|
3371
|
O'Brien C. Issues in designing and interpreting clinical trials of treatments for chronic hepatitis C. J Viral Hepat 2006; 13 Suppl 1:6-14. [PMID: 16630042 DOI: 10.1111/j.1365-2893.2006.00757.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/09/2022]
Abstract
Many of the major advances in treating patients for chronic hepatitis C have been made based on the results of randomized, double-blind, controlled clinical trials. However, given the large number of hepatitis C medications in development, physicians need to understand the unique elements and types of clinical trials in order to make accurate comparisons of differing drug efficacy claims. Clinicians also need to be aware of the various factors that can influence the outcomes and interpretations of these trials, irrespective of the intervention under study. For example, similar trials conducted in the United States and Europe may have different outcomes simply because the study populations differ. Thus, both trial design and patient population are important considerations in the design and analysis of clinical trials for patients with chronic hepatitis C.
Collapse
Affiliation(s)
- C O'Brien
- Division of GI, Center for Liver Diseases, University of Miami School of Medicine, Miami, FL 33136, USA.
| |
Collapse
|
3372
|
Deng CL, Song XW, Liang HJ, Feng C, Sheng YJ, Wang MY. Chronic hepatitis B serum promotes apoptotic damage in human renal tubular cells. World J Gastroenterol 2006; 12:1752-6. [PMID: 16586546 PMCID: PMC4124352 DOI: 10.3748/wjg.v12.i11.1752] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To investigate the effect of the serum of patients with chronic hepatitis B (CHB) on apoptosis of renal tubular epithelial cells in vitro and to study the role of hepatitis B virus (HBV) and transforming growth factor-β1 (TGF-β1) in the pathogenesis of hepatitis B virus associated glomerulonephritis (HBV-GN).
METHODS: The levels of serum TGF-β1 were measured by specific enzyme linked immunosorbent assay (ELISA) and HBV DNA was tested by polymerase chain reaction (PCR) in 44 patients with CHB ,and 20 healthy persons as the control. The normal human kidney proximal tubular cell (HK-2) was cultured together with the sera of healthy persons, CHB patients with HBV-DNA negative(20 cases) and HBV-DNA positive (24 cases) for up to 72 h. Apoptosis and Fas expression of the HK-2 were detected by flow cytometer.
RESULTS: The apoptosis rate and Fas expression of HK-2 cells were significantly higher in HBV DNA positive serum group 19.01±5.85% and 17.58±8.35%, HBV DNA negative serum group 8.12±2.80% and 6.96 ± 2.76% than those in control group 4.25±0.65% and 2.33 ±1.09%, respectively (P < 0.01). The apoptosis rate and Fas expression of HK-2 in HBV DNA positive serum group was significantly higher than those in HBV DNA negative serum (P < 0.01). Apoptosis rate of HK-2 cells in HBV DNA positive serum group was positively correlated with the level of HBV-DNA (r = 0.657). The level of serum TGF-β1 in CHB group was 163.05 ± 91.35 µg/L, significantly higher as compared with 81.40 ± 40.75 µg/L in the control group (P < 0.01).
CONCLUSION: The serum of patients with chronic hepatitis B promotes apoptotic damage in human renal tubular cells by triggering a pathway of Fas up-regulation. HBV and TGF-β1 may play important roles in the mechanism of hepatitis B virus associated glomerulonephritis.
Collapse
Affiliation(s)
- Cun-Liang Deng
- Department of Infectious Diseases, Affiliated Hospital of Luzhou Medical College, Luzhou 646000, Sichuan Province, China.
| | | | | | | | | | | |
Collapse
|
3373
|
Ramsey G. Treating coagulopathy in liver disease with plasma transfusions or recombinant factor VIIa: an evidence-based review. Best Pract Res Clin Haematol 2006; 19:113-26. [PMID: 16377545 DOI: 10.1016/j.beha.2005.01.034] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
In severe liver disease, poor synthetic function leads to characteristic deficiencies in numerous coagulation factors, and plasma transfusions are frequently administered to treat or prevent bleeding. This chapter reviews the available English-language randomized controlled trials, evidence-based practice guidelines, and observational studies relevant to establishing criteria for plasma transfusions in liver disease. The alternatives of pathogen-inactivated plasmas and recombinant factor VIIa were also reviewed from this perspective. In current guidelines, plasma transfusions are justified when haemostasis is needed for bleeding or invasive procedures, and the prothrombin time (PT) or partial thromboplastin time (PTT) is >1.5 times normal (mid-normal or, for PTT, sometimes upper limit). Conversion of the PT to the International Normalized Ratio has not been validated in liver disease. Solvent-detergent or methylene-blue treatments alter various clotting factors, which might affect efficacy in liver disease. Recombinant factor VIIa improves laboratory clotting measurements, but reduction of bleeding is less well established to date.
Collapse
Affiliation(s)
- Glenn Ramsey
- Blood Bank, Northwestern Memorial Hospital, Northwestern University, Feinberg 7-301, 251 East Huron Street, Chicago, IL 60611, USA.
| |
Collapse
|
3374
|
Farrugia A. Assessing Efficacy and Therapeutic Claims in Emerging Indications for Recombinant Factor VIIa: Regulatory Perspectives. Semin Hematol 2006; 43:S64-9. [PMID: 16427388 DOI: 10.1053/j.seminhematol.2005.11.013] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
When compared with the evidence-based, cost-effectiveness criteria underpinning most government reimbursement schemes in the social market economies, the three regulatory hurdles of safety, quality and efficacy are probably of modest impact in influencing increased usage of recombinant activated factor VII (rFVIIa; NovoSeven, Novo Nordisk, Bagsvaerd, Denmark). Nevertheless, efficacy claims must be supported if regulatory approval is to be granted for the wider range of indications that have been proposed for rFVIIa. With the refinement of clinical trial designs over the past 40 years, the randomized controlled trial (RCT) has assumed the role of gold standard, providing the highest level of evidence for therapeutic efficacy. However, it is incorrect to assume that regulatory authorities give sole credence to RCTs in assessing claims. It is noteworthy that the indications already accepted for rFVIIa by international regulatory authorities--including the treatment of inhibitors to factor VIII and factor IX, substitution for FVII deficiency, and treatment of Glanzmann's thrombasthenia--were supported not by RCTs but by studies conventionally considered to provide modest evidence levels. Therefore, the use of studies other than RCTs for the more recently proposed indications for rFVIIa in a range of conditions requiring hemostatic correction is perfectly feasible. What regulators expect are well-conducted and well-described studies adhering to principles of good clinical practice, which can be scrutinized for evidence of clinical efficacy and which are based on the initially proven principle for the drug. This paper discusses the regulatory history of rFVIIa in the major regulatory authorities and assesses the route needed to support claims being made in the mainstream literature. Recent episodes where post-market events have forced regulators to be more than usually cautious will be used as examples to suggest possible pitfalls to the extension of approved claims for rFVIIa. The major paths for enhancing access for indications in small patient numbers, where RCTs are even more difficult to perform, will be described and their use for possible extension of rFVIIa indications will be discussed.
Collapse
|
3375
|
|
3376
|
Hoots WK. Challenges in the Therapeutic Use of a “So-Called” Universal Hemostatic Agent: Recombinant Factor VIIa. Hematology 2006:426-31. [PMID: 17124094 DOI: 10.1182/asheducation-2006.1.426] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Abstract
Recombinant factor VIIa (rFVIIa) was developed in the early 1990s to provide “bypassing” hemostatic therapy for hemophilia A and B patients with inhibitors. More recently, it has been licensed for use in patients with inherited deficiency of factor VII. Since it was licensed for use in hemophilia with inhibitors in the US, Europe, and other countries for these specific indications, it has been used selectively but in a wide array of clinical settings for uncontrolled hemorrhage in individuals without an inherited bleeding disorder. Many of these uses have been described in the medical literature as case reports or small, uncontrolled series. Several randomized clinical trials (RCT) for these “off-label” medical uses have been published in recent months and will serve as the focus of this review. In particular, a review of an RCT for spontaneous intracranial hemorrhage that has demonstrated clinical efficacy in reducing both mortality and volume of central nervous system hemorrhage will be offered. A brief discussion of hypothesized physiologic mechanisms of supraphysiologic doses of rFVIIa will introduce the clinical discussion of these broad off-label uses. Since rFVIIa is a very expensive therapy, possible strategies for optimizing its use in the these settings will be presented.
Collapse
Affiliation(s)
- W Keith Hoots
- M.D. Anderson Cancer Center and University of Texas Health Science Center, Gulf States Hemophilia and Thrombophilia Center, 6655 Travis St., Suite 400, Houston TX 77030, USA.
| |
Collapse
|
3377
|
Obradović V, Artiko V, Radević B, Dapcević B, Petrović N. Hepatobilijarna scintigrafija u proceni funkcije transplantirane jetre. ACTA ACUST UNITED AC 2006; 53:23-7. [PMID: 16989142 DOI: 10.2298/aci0601023o] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The aim of the study is evaluation of hepatocellular function, as well as morphology and patency of the biliary three of the liver transplants by dynamic hepatobiliary scintigraphy. The study was performed in 10 controls and 10 patients after orthotopic transplantation (up to two years). Sixty minutes dynamic acquisition (1 frame/min) was performed with scintillation camera after injection of 360 MBq 99mTc-diethyl-IDA. Hepatobiliary scintigrams were analysed for morphology, and parenchymal and hepatobiliary TA curves were generated and analysed as regard to the time to maximal acitivity (Tmax) and the time to half of maximum acitivity (T1/2). Uptake of the radiopharmaceutical was slightly but not significantly delayed (Tmax=18.5+2.9 min) in comparison to the controls (Tmax=14.2+ 3.4min), while excretion was significantly prolonged (T1/2=59.5+ 12.1 min) than physiological (Tmax=34.2+4.1min). Intrahepatic bile flow was nonsignificantly prolonged (Tmax=31.3+3.7 min) in comparison to the controls (Tmax=25.7+ 3.5 min) while extrahepatic one is high significantly prolonged (T1/2=89.0+14.3 min) than physiological (T1/2 =45.0+ 7.2 min). Biliary phase of hepatobiliary scintigraphy showed increased accumulation of radiopharmaceutical in the left (n=1) or right (n=2) hepatic duct. Radionuclide methods are noninvasive, and apear to be sensitive and valuable for the monitoring of liver transplants.
Collapse
Affiliation(s)
- V Obradović
- Institut za nuklearnu medicinu, KCS, Beograd
| | | | | | | | | |
Collapse
|
3378
|
Abstract
Recombinant activated factor VII is a safe and effective for the treatment and prevention of haemorrhage in haemophiliacs with circulating inhibitors to replacement factors, and patients with Glanzmann's thrombasthenia refractory to platelet transfusion. By restoring thrombin generation on the surface of tissue factor bearing cells, such as activated platelets and monocytes, recombinant activated factor VII has the potential to effect haemostasis in the setting of many coagulopathic states encountered by the anaesthetist in the operating theatre or the intensive care unit. Case reports of successful rescue therapy make up the majority of the literature covering other, numerous, off-label uses of recombinant activated factor VII, although some randomised, controlled studies, mostly underpowered to address safety concerns, have been performed. However, off-label use is becoming increasingly popular judging by the number of published case reports. Additional randomised, controlled trials to determine the safe and appropriate use of this potentially valuable therapy in broader patient groups are eagerly awaited.
Collapse
Affiliation(s)
- I J Welsby
- Department of Anaesthesiology, Duke University Medical Center, Durham, NC 27710, USA.
| | | | | | | |
Collapse
|
3379
|
Pusateri AE, Park MS. Mechanistic implications for the use and monitoring of recombinant activated factor VII in trauma. CRITICAL CARE : THE OFFICIAL JOURNAL OF THE CRITICAL CARE FORUM 2005; 9 Suppl 5:S15-24. [PMID: 16221315 PMCID: PMC3226119 DOI: 10.1186/cc3781] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
As interest in the use of activated recombinant factor VII (rFVIIa) in trauma grows, questions arise regarding how best to monitor rFVIIa therapy and when rFVIIa may be expected to improve hemostasis. Knowledge of the mechanisms of action may be combined with available data on laboratory monitoring and efficacy in various coagulopathic states in coming to clinically relevant conclusions. This review addresses the physiology of hemostasis, placing emphasis on how rFVIIa influences the process by both tissue factor dependent and tissue factor independent mechanisms. This is extended to a mechanistic consideration of how rFVIIa may function under acidotic, hypothermic, and hemodilutional and/or consumptive conditions of trauma related coagulopathy. When these considerations are viewed alongside the available clinical data, it becomes apparent that rFVIIa has potential to improve hemostasis during trauma coagulopathy, within limitations. Common laboratory procedures are discussed with reference to mechanisms of action of rFVIIa and the available clinical data. Although there is no single assay that can predict rFVIIa efficacy in trauma, the prothrombin time (PT) is recommended as a minimum. Although a shortened PT does not predict success, correction of PT into the normal range may be a better indicator. A nonresponding PT appears to indicate that rFVIIa alone will not lead to hemostasis, and that additional blood products and other measures must be applied. Once the patient is more stable, PT and thromboelastography are recommended.
Collapse
|
3380
|
Grounds RM, Bolan C. Clinical experiences and current evidence for therapeutic recombinant factor VIIa treatment in nontrauma settings. Crit Care 2005; 9 Suppl 5:S29-36. [PMID: 16221317 PMCID: PMC3226121 DOI: 10.1186/cc3783] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
The hemostatic properties of recombinant activated factor VII (rFVIIa) are established in patients with inherited or acquired hemophilia with inhibitors and in patients with congenital factor VII deficiencies. Emerging clinical evidence suggests that there may be a wider role for rFVIIa in the management of hemorrhage associated with traumatic injury/accident and severe bleeding associated with critical surgery. This article considers recent data from studies in which rFVIIa was used in an attempt to control bleeding in clinical situations as diverse as coagulopathy associated with chronic liver disease, massive perioperative bleeding and bleeding during prostatectomy, organ transplantation and orthopedic surgery, uncontrollable obstetric hemorrhage, and intracerebral hemorrhage. In nontrauma settings involving acute and potentially life threatening bleeding, there may be a place for rFVIIa as adjunctive therapy in the control of hemostasis.
Collapse
|
3381
|
MacLaren R, Weber LA, Brake H, Gardner MA, Tanzi M. A multicenter assessment of recombinant factor VIIa off-label usage: clinical experiences and associated outcomes. Transfusion 2005; 45:1434-42. [PMID: 16131375 DOI: 10.1111/j.1537-2995.2005.00548.x] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND Off-label use of recombinant factor VIIa (rFVIIa) occurs despite minimal data. The purpose of this study was to describe prescribing practices and clinical outcomes for off-label rFVIIa use. STUDY DESIGN AND METHODS A retrospective, multicenter chart audit of 315 nonhemophiliac patients was performed. RESULTS Off-label indications included prevention of bleeding primarily related to procedural manipulation in 37.8 percent of patients and treatment of bleeding in 62.2 percent of patients. Baseline coagulopathy was present in 79.7 percent of patients. Prescriber specialty varied. The median doses for prevention and treatment were 75.6 and 89.4 microg per kg, respectively (p = 0.0006). The international normalized ratio (INR) decreased (p < 0.0001) from baseline in both groups. Transfusions of blood products were provided to 85.1 percent of patients before rFVIIa administration with considerable practice variation. Few patients received other procoagulant agents. In the prevention group, 14.3 percent of patients bled within 6 hours of their procedure. No variable was independently associated with bleeding prevention. In the treatment group, 52.6 percent of patients stopped bleeding within 6 hours of rFVIIa administration. The only independent variable associated with bleeding cessation was an arterial pH value of less than 7.20, which was a negative predictor (odds ratio, 0.207; 95% confidence interval, 0.084-0.507). Possible rFVIIa-associated adverse events occurred in 9.8 percent of patients and primarily involved undesirable clotting. No variable was independently associated with adverse events. CONCLUSIONS Off-label use of rFVIIa includes prevention and treatment of bleeding. rFVIIa is associated with INR reduction. Bleeding is rare with prophylactic rFVIIa but the cessation of bleeding is less than reported in the literature and may be related to pH. Possible adverse events are related to undesirable clotting.
Collapse
Affiliation(s)
- Robert MacLaren
- University of Colorado Health Sciences Center, School of Pharmacy, Department of Clinical Pharmacy, 4200 East Ninth Avenue, Denver, CO 80262, USA.
| | | | | | | | | |
Collapse
|
3382
|
Abstract
End stage liver disease results in a complex and variably severe failure of hemostasis that predisposes to abnormal bleeding. The diverse spectrum of hemostatic defects includes impaired synthesis of clotting factors, excessive fibrinolysis, disseminated intravascular coagulation, thrombocytopenia, and platelet dysfunction. Hemostasis screening tests are used to assess disease severity and monitor the response to therapy. Correction of hemostatic defects is required in patients who are actively bleeding or require invasive procedures. Fresh frozen plasma, cryoprecipitate, and platelet transfusion remain the mainstays of therapy until larger trials confirm the safety and efficacy of recombinant factor VIIa in this population.
Collapse
Affiliation(s)
- Jody L Kujovich
- Division of Hematology and Medical Oncology, Mail Code: L-586, Oregon Health & Science University, 3181 Sam Jackson Park Road, Portland, OR 97239-3098, USA.
| |
Collapse
|
3383
|
|
3384
|
Enomoto TM, Thorborg P. Emerging Off-Label Uses for Recombinant Activated Factor VII: Grading the Evidence. Crit Care Clin 2005; 21:611-32. [PMID: 15992675 DOI: 10.1016/j.ccc.2005.04.001] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Recombinant activated factor VII (rFVIIa) is currently licensed in the United States for treatment of bleeding episodes in patients with deficiencies of factor VIII (FVIII) or IX (FIX) who are refractory to factor replacement because of circulating inhibitors. A 1999 report of its successful use to stop what was deemed to be lethal hemorrhage after an abdominal gunshot wound in a young soldier without pre-existing coagulopathy has prompted exploration of other uses for rFVIIa. The virtual explosion of proposed uses of rFVIIa raises issues not only regarding our understanding of the coagulation system, but also regarding its efficacy, cost-effectiveness, and safety.
Collapse
Affiliation(s)
- T Miko Enomoto
- Division of Surgical Critical Care, Department of Surgery, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Mail Code L 223, Portland, OR 97201-3098, USA
| | | |
Collapse
|
3385
|
Wilson SJ, Bellamy MC, Giannoudis PV. The safety and efficacy of the administration of recombinant activated factor VII in major surgery and trauma patients. Expert Opin Drug Saf 2005; 4:557-70. [PMID: 15934860 DOI: 10.1517/14740338.4.3.557] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Recombinant activated Factor VII (rFVIIa) has been successfully used in the treatment of haemophilia A and B with associated inhibitors for some years. Activated Factor VII binds to activated platelets independently of tissue factor. The resulting stimulation of an exaggerated early thrombin burst at sites of vascular injury makes it an attractive potential treatment for massive, uncontrolled bleeding associated with surgery and trauma. This article describes the evidence relating to surgery and trauma. The lack of large, controlled trials of rFVIIa means that a definitive recommendation regarding its use cannot be made at present. However, in the context of clearly defined protocols and balanced treatment strategies, rFVIIa may have a role in traumatic bleeding. Large scale, randomised controlled trials in trauma are required, as is further work on the safety profile of rFVIIa with an independent international safety monitoring committee.
Collapse
Affiliation(s)
- Stephen J Wilson
- Department of Trauma, St James's University Hospital, Leeds LS9 7TF, UK
| | | | | |
Collapse
|
3386
|
Fridberg MJ, Hedner U, Roberts HR, Erhardtsen E. A study of the pharmacokinetics and safety of recombinant activated factor VII in healthy Caucasian and Japanese subjects. Blood Coagul Fibrinolysis 2005; 16:259-66. [PMID: 15870545 DOI: 10.1097/01.mbc.0000169218.15926.34] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
In this randomized, placebo-controlled, double-blind, single-centre, dose escalation study, we report the first evaluation of the pharmacokinetics and safety of recombinant activated factor VII (rFVIIa) in healthy Caucasian and Japanese subjects. Thirty-two healthy subjects were stratified according to sex and ethnic group to receive single bolus intravenous injections of three different doses of rFVIIa (40, 80, 160 microg/kg rFVIIa) or placebo, each separated by a 7-day wash-out period. Blood samples were taken up to 24 h after dosing. The factor VII clotting activity appeared to be dose dependent, but independent of sex and ethnic group. Statistical analyses demonstrated no significant effect of dose, sex or ethnicity on the dose-normalized mean area under the plasma concentration-time curve AUC0-t, indicating dose proportionality. No serious adverse events or thromboembolic events were reported. Analyses of coagulation parameters did not suggest induction of systemic coagulation when dosing rFVIIa up to 160 microg/kg. In conclusion, the pharmacokinetics of rFVIIa in Caucasian and Japanese subjects are similar, and no safety issues were identified.
Collapse
|
3387
|
Lam MSH, Sims-McCallum RP. Recombinant Factor VIIa in the Treatment of Non-Hemophiliac Bleeding. Ann Pharmacother 2005; 39:885-91. [PMID: 15784806 DOI: 10.1345/aph.1e553] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
OBJECTIVE: To review the clinical evidence for the use of recombinant factor VIIa (rFVIIa) in the prevention and/or treatment of bleeding in non-hemophiliac patients. DATA SOURCES: A MEDLINE search (1966–December 2004) was conducted to identify pertinent literature. Results were limited to English-language reports and clinical trials. References of relevant articles and selected abstracts presented at scientific meetings were also reviewed. STUDY SELECTION AND DATA EXTRACTION: Human data from prospective and retrospective studies that examined the hemostatic effect of rFVIIa in non-hemophiliac patients were reviewed, with a focus on surgical prophylaxis, liver disease, intractable bleeding associated with trauma and surgery, and anticoagulation reversal. DATA SYNTHESIS: Results from limited controlled trials on the use of rFVIIa as an adjunct for prevention of bleeding in surgery and liver diseases have not been consistent. For treatment of intractable bleeding, earlier use of rFVIIa in one trauma trial was shown to decrease the number of blood transfusions, but no differences in terms of clinical outcomes were observed in all trials. Controlled trials do not suggest an increased risk of thrombotic events. Optimal dosing and timing of administration have yet to be defined. CONCLUSIONS: Until further prospective controlled data are available, it is recommended that conventional intervention for prevention and control of hemorrhage in non-hemophiliac patients should remain the standard of care. Close monitoring of coagulation parameters is recommended before, during, and after therapy, especially in high-risk patients. Pharmacoeconomic analysis may be useful to help control costs and maximize clinical benefits.
Collapse
Affiliation(s)
- Masha S H Lam
- Hematology/Oncology, Shands, University of Florida, Gainesville, FL, USA.
| | | |
Collapse
|
3388
|
Dogan B. Dermatological manifestations in hepatitis B surface antigen carriers in east region of Turkey. J Eur Acad Dermatol Venereol 2005; 19:323-5. [PMID: 15857458 DOI: 10.1111/j.1468-3083.2004.01185.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND AND DESIGN Various cutaneous disorders associated with hepatitis B virus infection have been reported so far. Almost all of them were some peculiar eruptions or some disorders mainly based on immune complex reaction. OBJECTIVE The aim of this study was to compare the frequency of all dermatological disorders other than genetic ones in hepatitis B surface antigen (HBsAg) carrier patients and controls in our geographical area. METHODS Examinations were made on 88 hepatitis B carriers and 84 control patients, including entire skin surface, and oral and anogenital mucosa, and all the manifestations that could be seen were noted down. RESULTS While the number of HBsAg carrier patients with dermatological disorders was 62 (70.75%), it was only 24 (28.57%) in control patients. This seems statistically important: Yates' corrected chi-square test = 28.5; P = 0.0000001; odds ratio = 6.0 (2.94 < odds ratio < 12.2). The prevalence of oral lichen planus and pitted keratolysis in HBsAg carrier group was significantly higher than that of controls. We found the duration of positivity was not important statistically in the development of the dermatological disorders. CONCLUSIONS HBsAg positivity may induce or cause proneness to oral lichen planus and pitted keratolysis with some mechanism that needs to be elucidated.
Collapse
Affiliation(s)
- B Dogan
- Maresal Cakmak Hospital, Department of Dermatology, Erzurum, Turkey.
| |
Collapse
|
3389
|
Levi M, Peters M, Büller HR. Efficacy and safety of recombinant factor VIIa for treatment of severe bleeding: A systematic review. Crit Care Med 2005; 33:883-90. [PMID: 15818119 DOI: 10.1097/01.ccm.0000159087.85970.38] [Citation(s) in RCA: 200] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Recombinant activated factor VII (factor VIIa) is a prohemostatic agent that can be used for patients with complicated coagulation disorders. Recombinant factor VIIa is, however, increasingly used for several other indications, including patients with a preexistent normal coagulation system but who experience serious bleeding, for example, after major surgery or trauma. DATA SOURCE We performed a systematic review of all published and unpublished clinical studies using MEDLINE (1966-2004) and all other sources available to assess the available evidence on the efficacy and safety of recombinant factor VIIa in patients with or without coagulation disorders. STUDY SELECTION We found 483 articles related to the pharmacologic use of recombinant factor VIIa, including 28 clinical trials, 124 case series, and 176 case reports, which were all considered for this review. DATA SYNTHESIS Recombinant factor VIIa is an effective and relatively potent prohemostatic agent in approximately 90% of patients with hemophilia and inhibiting antibodies and other types of complex coagulation disorders. The application of recombinant factor VIIa in other patients who experience severe bleeding is promising, and although sound evidence from controlled clinical trials is only scarcely available so far, forthcoming trials are likely to provide more substantiation for this use. Recombinant factor VIIa appears to be relatively safe with a 1-2% incidence of thrombotic complications based on published trials. CONCLUSIONS More randomized controlled clinical trials are required to assess the efficacy and safety of recombinant factor VIIa for patients without a preexistent coagulation disorder and with severe bleeding. In the meantime, off-label use of recombinant factor VIIa may be considered in patients with life-threatening bleeding.
Collapse
Affiliation(s)
- Marcel Levi
- Department of Vascular Medicine/Internal Medicine, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands
| | | | | |
Collapse
|
3390
|
Lisman T, Adelmeijer J, Cauwenberghs S, Van Pampus ECM, Heemskerk JWM, De Groot PG. Recombinant factor VIIa enhances platelet adhesion and activation under flow conditions at normal and reduced platelet count. J Thromb Haemost 2005; 3:742-51. [PMID: 15842358 DOI: 10.1111/j.1538-7836.2005.01227.x] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND Recombinant factor VIIa (rFVIIa), which was developed for treatment of inhibitor-complicated hemophilia, appears suitable as prohemostatic agent in other clinical disorders including patients with thrombocytopenia. It is generally accepted that rFVIIa functions by enhancement of thrombin generation at the site of injury. It is, however, unknown if and how this affects platelet adhesion and aggregation. OBJECTIVES To determine the effect of rFVIIa-mediated thrombin generation on platelet adhesion and aggregation under flow conditions at normal and reduced platelet counts. METHODS Washed platelets and red cells were combined to obtain plasma-free blood with different platelet counts. The reconstituted blood was perfused over a collagen- or fibrinogen-coated surface in the absence or presence of a thrombin generating system consisting of purified coagulation factors rFVIIa, factor (F)X and prothrombin. RESULTS Addition of coagulation factors rFVIIa, FX and prothrombin to washed platelets and red cells enhanced platelet adhesion and aggregation to collagen and adhesion and spreading to fibrinogen at normal platelet count and at platelet numbers as low as 10 000 microL(-1). rFVIIa-mediated thrombin generation enhanced the activation state of platelets as measured by intracellular calcium fluxes, and enhanced the exposure of procoagulant phospholipids as measured by annexin A5 binding. CONCLUSIONS Taken together, increased platelet adhesion and aggregation by rFVIIa-mediated thrombin formation may explain the therapeutic effects of rFVIIa in thrombocytopenic conditions and in patients with a normal platelet count by (i) enhancement of primary hemostasis and (ii) enhancement of procoagulant surface leading to elevated fibrin formation.
Collapse
Affiliation(s)
- T Lisman
- Thrombosis and Hemostasis Laboratory, Department of Hematology, University Medical Center, Utrecht, The Netherlands.
| | | | | | | | | | | |
Collapse
|
3391
|
Mason A, Theal J, Bain V, Adams E, Perrillo R. Hepatitis B virus replication in damaged endothelial tissues of patients with extrahepatic disease. Am J Gastroenterol 2005; 100:972-6. [PMID: 15784044 DOI: 10.1111/j.1572-0241.2005.41308.x] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Hepatitis B virus (HBV) infection may be complicated by extrahepatic manifestations such as polyarteritis nodosa (PAN), glomerulonephritis, polymyositis, and dermatitis, but the etiology of these processes is not yet clear. HBV replication has been demonstrated in a variety of extrahepatic tissues and cell types, but the possible pathogenetic role of extrahepatic HBV replication has not been fully explored in patients with extrahepatic manifestations of HBV infection. In this case series, immunohistochemistry and in situ hybridization studies were performed on extrahepatic tissues from one HBsAg-positive patient with PAN and another HBsAg-positive patient with polymyositis, using HBsAg-seronegative control subjects with the same vasculitic disorders as controls. Tissue samples from the two study patients had detectable HBV RNA, replicative intermediates of HBV DNA, as well as HBsAg and HBcAg localized to vascular endothelium. In contrast, HBsAg-negative control patients had no tissue reactivity. Our results suggest that patients with HBV-related extrahepatic disease have evidence of viral replication in damaged extrahepatic endothelial tissues. While further studies would be required to support a hypothesis of causality, these findings suggest a role for both immune complex deposition and viral replication within diseased endothelial tissue in the pathogenesis of these poorly understood extrahepatic disorders.
Collapse
Affiliation(s)
- Andrew Mason
- Division of Gastroenterology, University of Alberta, Edmonton, Alberta, Canada
| | | | | | | | | |
Collapse
|
3392
|
Barletta JF, Ahrens CL, Tyburski JG, Wilson RF. A Review of Recombinant Factor VII for Refractory Bleeding in Nonhemophilic Trauma Patients. ACTA ACUST UNITED AC 2005; 58:646-51. [PMID: 15761369 DOI: 10.1097/01.ta.0000154561.97961.ad] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Recombinant factor VII (rFVII) is an attractive agent to control refractory, coagulopathic bleeding in patients following major surgery. The purpose of this review is to evaluate the published experiences of rFVII in adult, nonhemophilic, surgical and trauma patients. METHODS A computerized literature search was conducted to identify articles pertaining to rFVII use for refractory bleeding in adult, nonhemophilic, surgical patients. The selected articles were reviewed and the applicable data was analyzed. RESULTS A total of 117 patients were found in 8 case series and 24 case reports. Overall, rFVII was effective in restoring hemostasis in 99/117 (85%) patients with 76/99 (77%) surviving to hospital discharge. In trauma patients, hemostasis was achieved in 20/26 (77%) patients and 17/20 (85%) survived. There were 5 (4%) thromboembolic events observed in the 117 cases and much disparity was noted with the initial dose. Severe acidosis affected the activity of rFVII. CONCLUSION Recombinant factor VII is an effective therapeutic agent for achieving hemostasis in nonhemophilic surgical patients. Published clinical experiences, however, are limited to small case series and case reports.
Collapse
|
3393
|
Razon Y, Erez E, Vidne B, Birk E, Katz J, Tamari H, Dagan O. Recombinant factor VIIa (NovoSeven) as a hemostatic agent after surgery for congenital heart disease. Paediatr Anaesth 2005; 15:235-40. [PMID: 15725322 DOI: 10.1111/j.1460-9592.2005.01429.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Postoperative bleeding and blood product requirements can be substantial in children undergoing open-heart surgery, and reexploration is required in 1% of cases. Recombinant activated factor VII (rFVIIa, NovoSeven, NovoNordisk, Denmark) is a hemostatic agent approved for the treatment of hemophilic patients with inhibitors to factor VIII or factor IX. It has also been used with success in other conditions. We present our experience with rFVIIa treatment for uncontrolled bleeding after open-heart surgery in five pediatric patients. METHODS The study group consisted of five patients after open-heart surgery with excessive blood loss. The patients were treated with rFVIIa after failure of conventional treatment to control the bleeding. Blood loss, blood product consumption, and coagulation test results were recorded before and after rFVIIa administration. RESULTS In all cases, blood loss decreased considerably after rFVIIa administration (mean 7.8 ml x kg(-1) x h(-1)), almost eliminating the need for additional blood products, and the prolonged prothrombin time normalized. In two patients with thrombocytopathy, rFVIIa helped to discriminate surgical bleeding from bleeding caused by a defect in hemostasis. No side effects of rFVIIa treatment were noted. CONCLUSIONS These cases support the impression that RFVIIa is efficient and safe in correcting hemostasis in children after cardiopulmonary bypass when other means fail. However, the data are still limited, and more extensive research is needed.
Collapse
Affiliation(s)
- Yaron Razon
- Cardiac Intensive Care Unit, Schneider Children's Medical Center of Israel, Petah Tikva, Tel Aviv, Israel.
| | | | | | | | | | | | | |
Collapse
|
3394
|
Udvardy M, Telek B, Mezey G, Batar P, Altorjay I. Successful control of massive coumarol-induced acute upper gastrointestinal bleeding and correction of prothrombin time by recombinant active factor VII (Eptacog-alpha, NovoSeven) in a patient with a prosthetic aortic valve and two malignancies (chronic lymphoid leukaemia and lung cancer). Blood Coagul Fibrinolysis 2005; 15:265-7. [PMID: 15060425 DOI: 10.1097/00001721-200404000-00012] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Severe, life-threatening acute upper gastrointestinal bleeding may occasionally occur in patients receiving coumarol prophylaxis for prosthetic heart valves. These patients are exposed to two potential, serious risks: bleeding due to the severe blood loss induced by excessive anticoagulant effect or as a consequence of the cessation of anticoagulation subsequent thrombotic occlusion of the valve and loss of patency. Herein a short case report is presented. The elderly male patient had a prosthetic valve in the aortic position and also suffered from two malignant diseases: chronic lymphocytic leukaemia and a more recently developed lung cancer with metastatic spread into both lungs. The patient had a major gastrointestinal bleed, leading to a sudden fall of haematocrit (0.09), and to a collapse of peripheral circulation due to too excessive a coumarol effect (International Normalized Ratio > 8). An acute left ventricular failure developed during the early period of the emergency blood transfusion, so the correction of prothrombin time by fresh-frozen plasma (due to the large volume requirement) was not feasible. The patient received 50 microg/kg intravenous bolus of NovoSeven (recombinant active factor VII) in an almost desperate situation. The International Normalized Ratio changed to 2.1 in 30 min; bleeding had stopped immediately. There was neither evidence of disseminated intravascular coagulation (in spite of the age and underlying diseases) nor loss of valve patency or infective endocarditis during follow-up. This modest report may call attention to the potential use of recombinant active factor VII in the coumarol-induced severe bleeding episodes of prosthetic heart valve patients.
Collapse
Affiliation(s)
- Miklos Udvardy
- 2nd Department of Medicine, University Health and Medical Science Centre, Debrecen University, Hungary.
| | | | | | | | | |
Collapse
|
3395
|
Pettersson M, Fischler B, Petrini P, Schulman S, Nemeth A. Recombinant FVIIa in children with liver disease. Thromb Res 2005; 116:185-97. [PMID: 15935827 DOI: 10.1016/j.thromres.2004.11.020] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2004] [Revised: 11/21/2004] [Accepted: 11/25/2004] [Indexed: 10/26/2022]
Abstract
INTRODUCTION The aim of this study was to investigate the clinical and biochemical effects of recombinant activated factor VII (rFVIIa) in the treatment of bleeding in children with liver disease. PATIENTS AND METHODS 12 patients (0.3-15.9 years) with chronic liver disease were included. The indication for treatment was life threatening bleeding and failing conventional therapy (group A, 7 patients) or as prophylaxis before invasive procedures (group B, 6 patients). One patient received treatment on both indications. rFVIIa was administered as intravenous bolus doses of 34-163 microg/kg (median 66 mug/kg) alone or in combination with packed red cells and/or octreotide and/or fresh frozen plasma. The follow-up included repeated INR and haemoglobin measurements as well as clinical evaluation. RESULTS In group A rFVIIa was given on 22 occasions and bleeding decreased, was unchanged, increased or could not be evaluated on 10, 7, 2 and 3 occasions respectively. On 14 occasions rFVIIa and octreotide were administered simultaneously, in 8 of those bleeding decreased. In group B no bleeding complication was seen, interpreted as a positive effect. One thrombotic event was suspected but could not be verified by computerized tomography. CONCLUSIONS rFVIIa may be beneficial in the short-term management of life threatening bleeding in some children with liver disease. This effect may be further enhanced with the additional use of octreotide. Furthermore, rFVIIa is useful for prophylaxis at invasive procedures, even without additional treatment with fresh frozen plasma. The possible risk of portal vein thrombosis needs to be considered.
Collapse
Affiliation(s)
- Maria Pettersson
- Department of Paediatrics, Karolinska Institutet, Karolinska University Hospital, Huddinge, Stockholm S-141 86, Sweden.
| | | | | | | | | |
Collapse
|
3396
|
Sendensky A, Gutzwiller JP, Schneider-Frost J, Wuillemin WA, Graeni R, Beglinger C. Recombinant activated factor VII (NovoSeven) stops severe intra-abdominal bleeding after liver needle biopsy without surgery. Blood Coagul Fibrinolysis 2004; 15:701-2. [PMID: 15613927 DOI: 10.1097/00001721-200412000-00012] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
3397
|
Ludewig B, Krebs P, Metters H, Tatzel J, Türeci O, Sahin U. Molecular characterization of virus-induced autoantibody responses. ACTA ACUST UNITED AC 2004; 200:637-46. [PMID: 15353556 PMCID: PMC2212735 DOI: 10.1084/jem.20040358] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Here we present a comprehensive molecular mapping of virus-induced autoimmune B cell responses obtained by serological identification of antigens by recombinant expression cloning analysis. Immunoscreening of cDNA expression libraries of various organs (lung, liver, and spleen) using sera from mice infected with cytopathic (vaccinia virus [VV]) or noncytopathic (lymphocytic choriomeningitis virus [LCMV]) viruses revealed a broad specificity of the elicited autoantibody response. Interestingly, the majority of the identified autoantigens have been previously described as autoantigens in humans. We found that induction of virus-induced autoantibodies of the immunoglobulin G class largely depends on the CD40–CD40L-mediated interaction between T and B cells. Furthermore, antibody titers against a number of autoantigens were comparable to the concomitantly induced antiviral antibody response. Comparison of serum reactivity against a selected panel of autoantigens after infection with VV, LCMV, or vesicular stomatitis virus showed that the different virus infections triggered distinct autoantibody responses, suggesting that virus infections may leave specific “autoantibody fingerprints” in the infected host.
Collapse
Affiliation(s)
- Burkhard Ludewig
- Department of Pathology, Institute of Experimental Immunology, University Hospital Zürich, CH-8091 Zürich, Switzerland.
| | | | | | | | | | | |
Collapse
|
3398
|
Weiskopf RB. The use of recombinant activated coagulation factor VII for spine surgery. EUROPEAN SPINE JOURNAL : OFFICIAL PUBLICATION OF THE EUROPEAN SPINE SOCIETY, THE EUROPEAN SPINAL DEFORMITY SOCIETY, AND THE EUROPEAN SECTION OF THE CERVICAL SPINE RESEARCH SOCIETY 2004; 13 Suppl 1:S83-8. [PMID: 15160317 PMCID: PMC3592181 DOI: 10.1007/s00586-004-0736-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2004] [Accepted: 04/23/2004] [Indexed: 11/29/2022]
Abstract
This article focuses on our current understanding of the role of activated coagulation factor VII (FVIIa) in coagulation, the current evidence regarding the efficacy and safety of recombinant FVIIa (rFVIIa), and thoughts regarding the use of rFVIIa in spine surgery. rFVIIa is approved in many countries (including the European Union and the USA) for patients with hemophilia and inhibitors (antibodies) to coagulation factors VIII or IX. High circulating concentrations of FVIIa, achieved by exogenous administration, initiate hemostasis by combining with tissue factor at the site of injury, producing thrombin, activating platelets and coagulation factors II, IX and X, thus providing for the full thrombin burst that is essential for hemostasis. This "bypass" therapy has led some clinicians to use rFVIIa "off-label" for disorders of hemostasis other than hemophilia. Based on clinical experience, case reports and limited information from clinical trials, rFVIIa may be efficacious in states of decreased concentration of coagulation factors, thrombocytopenia, and at least some states of altered platelet function. The former two can occur intra-operatively during spinal surgery as a consequence of substantial blood loss and normal consumption. Preliminary reports have indicated that rFVIIa does not increase the perioperative incidence of thromboembolic events. However, full reports from large clinical trials regarding the efficacy and safety of rFVIIa in settings other than hemophilia have yet to appear in peer-reviewed publications. Until adequate data demonstrating safety and efficacy are fully reported, it would seem appropriate to reserve the use of rFVIIa in spinal surgery to those instances where conventional therapy cannot provide adequate hemostasis, and "rescue" therapy is required.
Collapse
Affiliation(s)
- Richard B Weiskopf
- Department of Anesthesia and Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA 94143-0648, USA.
| |
Collapse
|
3399
|
Abstract
Human coagulation factor (F) VII is a single chain protease that circulates in the blood as a weakly active zymogen at concentrations of approximately 10 nmol/L. When converted to the active 2 chain form (FVIIa), it is a powerful initiator of haemostasis. Recombinant factor VIIa (rFVIIa, eptacog alfa, NovoSeven) is a genetically engineered product that was first introduced in 1988 for the treatment of patients with haemophilia A and B with high inhibitory antibody titres to factors VIII and IX. Recent reports in the form of case studies and series, and early trial data, have suggested a role for rFVIIa across a diverse range of indications including bleeding associated with trauma, surgery, thrombocytopaenia, liver disease and oral anticoagulant toxicity. This review describes the physiology of the coagulation pathway and in particular the role of recombinant factor VIIa. It will also focus on the emerging role of rFVIIa in both trauma and non-trauma bleeding and its potential use in the ED.
Collapse
Affiliation(s)
- Michael G Aitken
- Allamanda Emergency Care Centre, Allamanda Private Hospital, Southport, Queensland, Australia.
| |
Collapse
|
3400
|
Goodnough LT, Lublin DM, Zhang L, Despotis G, Eby C. Transfusion medicine service policies for recombinant factor VIIa administration. Transfusion 2004; 44:1325-31. [PMID: 15318856 DOI: 10.1111/j.1537-2995.2004.04052.x] [Citation(s) in RCA: 100] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Recombinant FVIIa (rFVIIa) has been approved for treatment of bleeding in hemophilia patients with inhibitors. It has also been successfully used in nonhemophilia patients with acquired antibodies against FVIII (acquired hemophilia). Pharmacological doses of rFVIIa have been found to enhance the thrombin generation on already activated platelets and, therefore, may also likely be of benefit in providing hemostasis in other situations characterized by profuse bleeding and impaired thrombin generation, such as patients with thrombocytopenia and in those with functional platelet defects. Additionally, it has been used successfully in a variety of less well-characterized bleeding situations, as well as in patients with impaired liver function. To date, case reports, anecdotal experience, and limited clinical trials describe these uses; data from randomized clinical trials are limited. Because of the recent trends in rFVIIa usage in non-approved settings among physicians from various disciplines, significant concerns about its safety, efficacy, and costs have arisen. Additionally, dosing of rFVIIa for these potentially broad clinical applications is not standardized. Currently, the decision on when and where to use rFVIIa for patients with uncontrolled bleeding continues to be one that must be made by individual physicians, assisted by their hospital pharmacotherapeutics and transfusion committees.
Collapse
Affiliation(s)
- Lawrence Tim Goodnough
- Department of Medicine, Washington University School of Medicine Barnes-Jewish Hospital, St. Louis, Missouri, USA.
| | | | | | | | | |
Collapse
|