| Item |
Information |
|
Drug Groups
|
approved; investigational |
|
Description
|
Fondaparinux (Arixtra) is a synthetic pentasaccharide anticoagulant. Apart from the O-methyl group at the reducing end of the molecule, the identity and sequence of the five monomeric sugar units contained in fondaparinux is identical to a sequence of five monomeric sugar units that can be isolated after either chemical or enzymatic cleavage of the polymeric glycosaminoglycan heparin and heparan sulfate (HS). This monomeric sequence in heparin and HS is thought to form the high affinity binding site for the natural anti-coagulant factor, antithrombin III (ATIII). Binding of heparin/HS to ATIII has been shown to increase the anti-coagulant activity of antithrombin III 1000-fold. Fondaparinux potentiates the neutralizing action of ATIII on activated Factor X 300-fold. Fondaparinux may be used: to prevent venous thromboembolism in patients who have undergone orthopedic surgery of the lower limbs (e.g. hip fracture, hip replacement and knee surgery); to prevent VTE in patients undergoing abdominal surgery who are are at high risk of thromboembolic complications; in the treatment of deep vein thrombosis (DVT) and pumonary embolism (PE); in the management of unstable angina (UA) and non-ST segment elevation myocardial infarction (NSTEMI); and in the management of ST segment elevation myocardial infarction (STEMI). |
| Indication |
Approved for: (1) prophylaxis of VTE for up to one month post surgery in patients undergoing orthopedic surgery of the lower limbs such as hip fracture, hip replacement and knee surgery; (2) prophylaxis of VTE patients undergoing abdominal surgery who are at high risk of thromboembolic complications (e.g. patients undergoing abdominal cancer surgery); (3) treatment of acute DVT and PE; (4) management of UA and NSTEMI for the prevention of death and subsequent myocardial infarction (MI); and (5) management of STEMI for the prevention of death and myocardial reinfarction in patients who are managed with thrombolytics or who are initially to receive no form of reperfusion therapy. Fondaparinux should not be used as the sole anticoagulant during percutaneous coronary intervention (PCI) due to an increased risk of guiding catheter thrombosis. |
| Pharmacology |
Fondaparinux binds specifically to the natural anticoagulant factor, ATIII. Binding to ATIII potentiates the neutralizing action of ATIII on Factor Xa 300-times. Neutralization of Factor Xa decreases the conversion of prothrombin to thrombin, which subsequently decreases the conversion of fibrinogen to fibrin (loose meshwork). The decrease in thrombin also decreases the activation of Factor XIII, which decreases the conversion of fibrin in its loose meshwork form to its stabilized meshwork form. Disruption of the coagulation cascade effectively decreases the formation of blood clots. Fondaparinux does not inactivate thrombin (activated Factor II). According to the manufacturer, fondaparinux has no known effect on platelet function. In studies comparing fondaparinux to enoxaparin, decreases in platelet levels were observed in similar numbers of patients from both groups (2-5%) (PMID 11794148, 12049860). At the recommended dose, Fondaparinux does not affect fibrinolytic activity or bleeding time. There is no antidote for fondaparinux. Monitoring of the anticoagulant activity of fondaparinux is not generally required. The anti-factor Xa assay may be used to monitor therapy in special populations such as those with renal impairment or who are pregnant. Complete blood count (CBC) and kidney function should be monitored during treatment. |
| Toxicity |
As with other anticoagulants, the main concern is increased bleed risk. The risk of hemorrhage may increase with decreased renal function, body mass less than 50 kg, and moderate to severe hepatic function. |
| Affected Organisms |
| • |
Humans and other mammals |
|
| Biotransformation |
Not metabolized |
| Absorption |
100% bioavailability when administered subcutaneously |
| Half Life |
17-21 hours |
| Protein Binding |
94% in vitro protein binding specifically to ATIII |
| Elimination |
In individuals with normal kidney function, fondaparinux is eliminated in urine mainly as unchanged drug. |
| Distribution |
* 7 - 11 L (healthy adults), distributed primarily in blood |
| References |
| • |
GlaxoSmithKline. Arixtra® (fondaparinux sodium) injection prescribing information. Mississauga, ON. 2010 May. |
| • |
Eriksson BI, Bauer KA, Lassen MR, Turpie AG: Fondaparinux compared with enoxaparin for the prevention of venous thromboembolism after hip-fracture surgery. N Engl J Med. 2001 Nov 1;345(18):1298-304.
[Pubmed]
|
| • |
Turpie AG, Bauer KA, Eriksson BI, Lassen MR: Postoperative fondaparinux versus postoperative enoxaparin for prevention of venous thromboembolism after elective hip-replacement surgery: a randomised double-blind trial. Lancet. 2002 May 18;359(9319):1721-6.
[Pubmed]
|
| • |
Lassen MR, Bauer KA, Eriksson BI, Turpie AG: Postoperative fondaparinux versus preoperative enoxaparin for prevention of venous thromboembolism in elective hip-replacement surgery: a randomised double-blind comparison. Lancet. 2002 May 18;359(9319):1715-20.
[Pubmed]
|
| • |
Bauer KA, Eriksson BI, Lassen MR, Turpie AG: Fondaparinux compared with enoxaparin for the prevention of venous thromboembolism after elective major knee surgery. N Engl J Med. 2001 Nov 1;345(18):1305-10.
[Pubmed]
|
| • |
Bauer KA, Eriksson BI, Lassen MR, Turpie AG: Fondaparinux compared with enoxaparin for the prevention of venous thromboembolism after elective major knee surgery. N Engl J Med. 2001 Nov 1;345(18):1305-10.
[Pubmed]
|
| • |
Agnelli G, Bergqvist D, Cohen AT, Gallus AS, Gent M: Randomized clinical trial of postoperative fondaparinux versus perioperative dalteparin for prevention of venous thromboembolism in high-risk abdominal surgery. Br J Surg. 2005 Oct;92(10):1212-20.
[Pubmed]
|
| • |
Buller HR, Davidson BL, Decousus H, Gallus A, Gent M, Piovella F, Prins MH, Raskob G, Segers AE, Cariou R, Leeuwenkamp O, Lensing AW: Fondaparinux or enoxaparin for the initial treatment of symptomatic deep venous thrombosis: a randomized trial. Ann Intern Med. 2004 Jun 1;140(11):867-73.
[Pubmed]
|
| • |
Buller HR, Davidson BL, Decousus H, Gallus A, Gent M, Piovella F, Prins MH, Raskob G, van den Berg-Segers AE, Cariou R, Leeuwenkamp O, Lensing AW: Subcutaneous fondaparinux versus intravenous unfractionated heparin in the initial treatment of pulmonary embolism. N Engl J Med. 2003 Oct 30;349(18):1695-702.
[Pubmed]
|
| • |
Yusuf S, Mehta SR, Chrolavicius S, Afzal R, Pogue J, Granger CB, Budaj A, Peters RJ, Bassand JP, Wallentin L, Joyner C, Fox KA: Comparison of fondaparinux and enoxaparin in acute coronary syndromes. N Engl J Med. 2006 Apr 6;354(14):1464-76. Epub 2006 Mar 14.
[Pubmed]
|
| • |
Bassand JP, Richard-Lordereau I, Cadroy Y: Efficacy and safety of fondaparinux in patients with acute coronary syndromes. Expert Rev Cardiovasc Ther. 2007 Nov;5(6):1013-26.
[Pubmed]
|
| • |
Steg PG, Jolly SS, Mehta SR, Afzal R, Xavier D, Rupprecht HJ, Lopez-Sendon JL, Budaj A, Diaz R, Avezum A, Widimsky P, Rao SV, Chrolavicius S, Meeks B, Joyner C, Pogue J, Yusuf S: Low-dose vs standard-dose unfractionated heparin for percutaneous coronary intervention in acute coronary syndromes treated with fondaparinux: the FUTURA/OASIS-8 randomized trial. JAMA. 2010 Sep 22;304(12):1339-49. Epub 2010 Aug 31.
[Pubmed]
|
| • |
Yusuf S, Mehta SR, Chrolavicius S, Afzal R, Pogue J, Granger CB, Budaj A, Peters RJ, Bassand JP, Wallentin L, Joyner C, Fox KA: Effects of fondaparinux on mortality and reinfarction in patients with acute ST-segment elevation myocardial infarction: the OASIS-6 randomized trial. JAMA. 2006 Apr 5;295(13):1519-30. Epub 2006 Mar 14.
[Pubmed]
|
| • |
Kovacs MJ: Successful treatment of heparin induced thrombocytopenia (HIT) with fondaparinux. Thromb Haemost. 2005 May;93(5):999-1000.
[Pubmed]
|
| • |
Ortel TL: Heparin-induced thrombocytopenia: when a low platelet count is a mandate for anticoagulation. Hematology Am Soc Hematol Educ Program. 2009:225-32.
[Pubmed]
|
| • |
Moser M, Bode C: New antithrombotic agents in acute coronary syndromes. Curr Opin Cardiol. 2009 Jul;24(4):313-7.
[Pubmed]
|
| • |
Hirsh J, Bauer KA, Donati MB, Gould M, Samama MM, Weitz JI: Parenteral anticoagulants: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines (8th Edition). Chest. 2008 Jun;133(6 Suppl):141S-159S.
[Pubmed]
|
| • |
Geerts WH, Bergqvist D, Pineo GF, Heit JA, Samama CM, Lassen MR, Colwell CW: Prevention of venous thromboembolism: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines (8th Edition). Chest. 2008 Jun;133(6 Suppl):381S-453S.
[Pubmed]
|
| • |
Kearon C, Kahn SR, Agnelli G, Goldhaber S, Raskob GE, Comerota AJ: Antithrombotic therapy for venous thromboembolic disease: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines (8th Edition). Chest. 2008 Jun;133(6 Suppl):454S-545S.
[Pubmed]
|
| • |
Anderson JL, Adams CD, Antman EM, Bridges CR, Califf RM, Casey DE Jr, Chavey WE 2nd, Fesmire FM, Hochman JS, Levin TN, Lincoff AM, Peterson ED, Theroux P, Wenger NK, Wright RS, Smith SC Jr, Jacobs AK, Adams CD, Anderson JL, Antman EM, Halperin JL, Hunt SA, Krumholz HM, Kushner FG, Lytle BW, Nishimura R, Ornato JP, Page RL, Riegel B: ACC/AHA 2007 guidelines for the management of patients with unstable angina/non-ST-Elevation myocardial infarction: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Writing Committee to Revise the 2002 Guidelines for the Management of Patients With Unstable Angina/Non-ST-Elevation Myocardial Infarction) developed in collaboration with the American College of Emergency Physicians, the Society for Cardiovascular Angiography and Interventions, and the Society of Thoracic Surgeons endorsed by the American Association of Cardiovascular and Pulmonary Rehabilitation and the Society for Academic Emergency Medicine. J Am Coll Cardiol. 2007 Aug 14;50(7):e1-e157.
[Pubmed]
|
| • |
Goodman SG, Menon V, Cannon CP, Steg G, Ohman EM, Harrington RA: Acute ST-segment elevation myocardial infarction: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines (8th Edition). Chest. 2008 Jun;133(6 Suppl):708S-775S.
[Pubmed]
|
| • |
Warkentin TE, Greinacher A, Koster A, Lincoff AM: Treatment and prevention of heparin-induced thrombocytopenia: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines (8th Edition). Chest. 2008 Jun;133(6 Suppl):340S-380S.
[Pubmed]
|
| • |
Harrington RA, Becker RC, Cannon CP, Gutterman D, Lincoff AM, Popma JJ, Steg G, Guyatt GH, Goodman SG: Antithrombotic therapy for non-ST-segment elevation acute coronary syndromes: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines (8th Edition). Chest. 2008 Jun;133(6 Suppl):670S-707S.
[Pubmed]
|
|
| External Links |
|
|